GitHub/exynos8895/android_kernel_samsung_universal8895.git
12 years agomac80211: fix work removal on deauth request
Johannes Berg [Wed, 18 Jan 2012 13:10:25 +0000 (14:10 +0100)]
mac80211: fix work removal on deauth request

When deauth is requested while an auth or assoc
work item is in progress, we currently delete it
without regard for any state it might need to
clean up. Fix it by cleaning up for those items.

In the case Pontus found, the problem manifested
itself as such:

authenticate with 00:23:69:aa:dd:7b (try 1)
authenticated
failed to insert Dummy STA entry for the AP (error -17)
deauthenticating from 00:23:69:aa:dd:7b by local choice (reason=2)

It could also happen differently if the driver
uses the tx_sync callback.

We can't just call the ->done() method of the work
items because that will lock up due to the locking
in cfg80211. This fix isn't very clean, but that
seems acceptable since I have patches pending to
remove this code completely.

Cc: stable@vger.kernel.org
Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com>
Tested-by: Pontus Fuchs <pontus.fuchs@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agomac80211: Use the right headroom size for mesh mgmt frames
Javier Cardona [Wed, 18 Jan 2012 02:17:46 +0000 (18:17 -0800)]
mac80211: Use the right headroom size for mesh mgmt frames

Use local->tx_headroom instad of local->hw.extra_tx_headroom.
local->tx_headroom is the max of hw.extra_tx_headroom required by the
driver and the headroom required by mac80211 for status reporting.  On
drivers where hw.extra_tx_headroom is smaller than what mac80211
requires (e.g. ath5k), we would not reserve sufficient buffer space to
report tx status.

Also, don't reserve local->tx_headroom + local->hw.extra_tx_headroom.

Reported-by: Simon Morgenthaler <s.morgenthaler@students.unibe.ch>
Reported-by: Kai Scharwies <kai@scharwies.de>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobrcmsmac: fix tx queue flush infinite loop
Stanislaw Gruszka [Tue, 17 Jan 2012 11:38:50 +0000 (12:38 +0100)]
brcmsmac: fix tx queue flush infinite loop

This patch workaround live deadlock problem caused by infinite loop
in brcms_c_wait_for_tx_completion(). I do not consider the patch as
the proper fix, which should fix the real reason of tx queue flush
failure, but patch helps with system lockup.

Reference:
https://bugzilla.kernel.org/show_bug.cgi?id=42576

Reported-and-tested-by: Patrick <ragamuffin@datacomm.ch>
Cc: stable@vger.kernel.org # 3.2+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agomac80211: fix debugfs key->station symlink
Johannes Berg [Tue, 17 Jan 2012 09:32:01 +0000 (10:32 +0100)]
mac80211: fix debugfs key->station symlink

Since stations moved into a virtual interface
subdirectory, this link has been broken. Fix it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agotg3: Fix single-vector MSI-X code
Matt Carlson [Tue, 17 Jan 2012 15:27:23 +0000 (15:27 +0000)]
tg3: Fix single-vector MSI-X code

Kdump kernels leave MSI-X interrupts (as setup by the crashed kernel)
enabled.  However, kdump only enables one CPU in the new environment,
thus causing tg3 to abort MSI-X setup.  When the driver attempts to
enable INTA or MSI interrupt modes on a kdump kernel, interrupt
delivery fails.

This patch attempts to workaround the problem by forcing the driver
to enable a single MSI-X interrupt.  In such a configuration, the
device's multivector interrupt mode must be disabled.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoopenvswitch: Fix multipart datapath dumps.
Ben Pfaff [Tue, 17 Jan 2012 13:33:39 +0000 (13:33 +0000)]
openvswitch: Fix multipart datapath dumps.

The logic to split up the list of datapaths into multiple Netlink messages
was simply wrong, causing the list to be terminated after the first part.
Only about the first 50 datapaths would be dumped.  This fixes the
problem.

Reported-by: Paul Ingram <paul@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoipv6: fix per device IP snmp counters
Eric Dumazet [Tue, 17 Jan 2012 12:45:36 +0000 (12:45 +0000)]
ipv6: fix per device IP snmp counters

In commit 4ce3c183fca (snmp: 64bit ipstats_mib for all arches), I forgot
to change the /proc/net/dev_snmp6/xxx output for IP counters.

percpu array is 64bit per counter but the folding still used the 'long'
variant, and output garbage on 32bit arches.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoinetpeer: initialize ->redirect_genid in inet_getpeer()
Dan Carpenter [Tue, 17 Jan 2012 10:48:43 +0000 (10:48 +0000)]
inetpeer: initialize ->redirect_genid in inet_getpeer()

kmemcheck complains that ->redirect_genid doesn't get initialized.
Presumably it should be set to zero.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: fix NULL-deref in WARN() in skb_gso_segment()
Michał Mirosław [Tue, 17 Jan 2012 10:00:40 +0000 (10:00 +0000)]
net: fix NULL-deref in WARN() in skb_gso_segment()

Bug was introduced in commit c8f44affb7244f2ac3e703cab13d55ede27621bb.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: WARN if skb_checksum_help() is called on skb requiring segmentation
Ben Hutchings [Tue, 17 Jan 2012 07:57:56 +0000 (07:57 +0000)]
net: WARN if skb_checksum_help() is called on skb requiring segmentation

skb_checksum_help() has never done anything useful with skbs that
require segmentation.  Setting skb->ip_summed = CHECKSUM_NONE makes
them invalid and provokes a later WARNing in skb_gso_segment().

Passing such an skb to skb_checksum_help() indicates a bug, so we
should warn about it immediately.  Move the warning from
skb_gso_segment() into a shared function, and add gso_type and
gso_size to it.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoMerge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
David S. Miller [Tue, 17 Jan 2012 17:11:52 +0000 (12:11 -0500)]
Merge branch 'master' of git://git./linux/kernel/git/linville/wireless

12 years agocaif: Remove bad WARN_ON in caif_dev
sjur.brandeland@stericsson.com [Tue, 17 Jan 2012 03:03:14 +0000 (03:03 +0000)]
caif: Remove bad WARN_ON in caif_dev

Remove WARN_ON and bad handling of SKB without destructor callback
in caif_flow_cb. SKB without destructor cannot be handled as an
error case.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agocaif: Fix typo in Vendor/Product-ID for CAIF modems
sjur.brandeland@stericsson.com [Tue, 17 Jan 2012 03:03:13 +0000 (03:03 +0000)]
caif: Fix typo in Vendor/Product-ID for CAIF modems

Fix typo for the Vendor/Product Id for ST-Ericsson CAIF modems.
Discovery is based on fixed USB vendor 0x04cc (ST-Ericsson),
product-id 0x230f (NCM).

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobnx2x: Disable AN KR work-around for BCM57810
Yaniv Rosner [Tue, 17 Jan 2012 02:33:29 +0000 (02:33 +0000)]
bnx2x: Disable AN KR work-around for BCM57810

Disable the work-around for the autoneg KR of the BCM57810 in case the Warpcore version is 0xD108 and above, which fixes this problem.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobnx2x: Remove AutoGrEEEn for BCM84833
Yaniv Rosner [Tue, 17 Jan 2012 02:33:28 +0000 (02:33 +0000)]
bnx2x: Remove AutoGrEEEn for BCM84833

Disable the autoGrEEEn feature for BCM84833.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobnx2x: Remove 100Mb force speed for BCM84833
Yaniv Rosner [Tue, 17 Jan 2012 02:33:27 +0000 (02:33 +0000)]
bnx2x: Remove 100Mb force speed for BCM84833

Remove unsupported speed of 100Mb force for BCM84833 due to hardware
limitation.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobnx2x: Fix PFC setting on BCM57840
Yaniv Rosner [Tue, 17 Jan 2012 02:33:26 +0000 (02:33 +0000)]
bnx2x: Fix PFC setting on BCM57840

This patch handles the second port of a path in a 4-port device of
BCM57840.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobnx2x: Fix Super-Isolate mode for BCM84833
Yaniv Rosner [Tue, 17 Jan 2012 02:33:25 +0000 (02:33 +0000)]
bnx2x: Fix Super-Isolate mode for BCM84833

The Super-Isolate mode comes to isolate the BCM84833 PHY from the
outside world.  Not doing it correctly, made link partner see the link
before the driver was loaded.

This patch also involves SPIROM version fixes since it is used to
determine whether the common init of the PHY was already executed, and
the common init of this PHY is partially responsible for setting the
Super-Isolate mode.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: fix some sparse errors
Eric Dumazet [Mon, 16 Jan 2012 19:27:39 +0000 (19:27 +0000)]
net: fix some sparse errors

make C=2 CF="-D__CHECK_ENDIAN__" M=net

And fix flowi4_init_output() prototype for sport

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: kill duplicate included header
Shan Wei [Mon, 16 Jan 2012 18:34:24 +0000 (18:34 +0000)]
net: kill duplicate included header

For net part, remove duplicate included header.

Signed-off-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: sh-eth: Fix build error by the value which is not defined
Nobuhiro Iwamatsu [Mon, 16 Jan 2012 16:50:16 +0000 (16:50 +0000)]
net: sh-eth: Fix build error by the value which is not defined

-----
drivers/net/ethernet/renesas/sh_eth.c:1706: error: 'pdid' undeclared (first use in this function)
drivers/net/ethernet/renesas/sh_eth.c:1706: error: (Each undeclared identifier is reported only once
drivers/net/ethernet/renesas/sh_eth.c:1706: error: for each function it appears in.)
make[5]: *** [drivers/net/ethernet/renesas/sh_eth.o] Error 1
-----

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
CC: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: Use device model to get driver name in skb_gso_segment()
Ben Hutchings [Mon, 16 Jan 2012 12:38:59 +0000 (12:38 +0000)]
net: Use device model to get driver name in skb_gso_segment()

ethtool operations generally require the caller to hold RTNL and are
not safe to call in atomic context.  The device model provides this
information for most devices; we'll only lose it for some old ISA
drivers.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobridge: BH already disabled in br_fdb_cleanup()
Eric Dumazet [Mon, 16 Jan 2012 04:35:50 +0000 (04:35 +0000)]
bridge: BH already disabled in br_fdb_cleanup()

br_fdb_cleanup() is run from timer interrupt, BH already masked.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Štefan Gula <steweg@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agonet: move sock_update_memcg outside of CONFIG_INET
Glauber Costa [Sun, 15 Jan 2012 22:04:39 +0000 (22:04 +0000)]
net: move sock_update_memcg outside of CONFIG_INET

Although only used currently for tcp sockets, this function
is now used in common sock code (for sock_clone())

Commit 475f1b52645a29936b9df1d8fcd45f7e56bd4a9f moved the
declaration of sock_update_clone() to inside sock.c, but
this only fixes the problem when CONFIG_CGROUP_MEM_RES_CTLR_KMEM
is also not defined.

This patch here is verified to fix both problems, although
reverting the previous one is not necessary.

Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: David S. Miller <davem@davemloft.net>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agomwl8k: Fixing Sparse ENDIAN CHECK warning
Yogesh Ashok Powar [Tue, 17 Jan 2012 10:15:15 +0000 (15:45 +0530)]
mwl8k: Fixing Sparse ENDIAN CHECK warning

Fixing following sparse warning
>drivers/net/wireless/mwl8k.c:2780:15: warning: incorrect type in assignment (different base types)
>drivers/net/wireless/mwl8k.c:2780:15:    expected restricted unsigned short [usertype] channel
>drivers/net/wireless/mwl8k.c:2780:15:    got unsigned short [unsigned] [usertype] hw_value

Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agomac80211: Fix possible race between sta_unblock and network softirq
Helmut Schaa [Tue, 17 Jan 2012 08:22:49 +0000 (09:22 +0100)]
mac80211: Fix possible race between sta_unblock and network softirq

All other code paths in sta_unblock synchronize with the network
softirq by using local_bh_disable/enable. Do the same around
ieee80211_sta_ps_deliver_wakeup.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agomwl8k: fix condition in mwl8k_cmd_encryption_remove_key()
Dan Carpenter [Tue, 17 Jan 2012 07:33:31 +0000 (10:33 +0300)]
mwl8k: fix condition in mwl8k_cmd_encryption_remove_key()

The intent here was to check whether key->cipher was WEP40 or WEP104.
We do a similar check correctly in several other places in this file.
The current condition is always true.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobrcmfmac: work-around gcc 4.7 build issue
Alexandre Oliva [Mon, 16 Jan 2012 19:00:12 +0000 (14:00 -0500)]
brcmfmac: work-around gcc 4.7 build issue

Alexandre Oliva <oliva@lsd.ic.unicamp.br> says:

"It's an issue brought about by GCC 4.7's partial-inlining, that ends up
splitting the udelay function just at the wrong spot, in such a way that
some sanity checks for constants fails, and we end up calling
bad_udelay.

This patch fixes the problem.  Feel free to push it upstream if it makes
sense to you."

Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agonet: remove version.h includes in net/openvswitch/
Devendra Naga [Sat, 14 Jan 2012 08:16:21 +0000 (08:16 +0000)]
net: remove version.h includes in net/openvswitch/

remove version.h includes in net/openswitch/ as reported by make versioncheck.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobql: Fix inconsistency between file mode and attr method.
Hiroaki SHIMODA [Sat, 14 Jan 2012 07:10:21 +0000 (07:10 +0000)]
bql: Fix inconsistency between file mode and attr method.

There is no store() method for inflight attribute in the
tx-<n>/byte_queue_limits sysfs directory.
So remove S_IWUSR bit.

Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoehea: make some functions and variables static
Thadeu Lima de Souza Cascardo [Fri, 13 Jan 2012 08:06:32 +0000 (08:06 +0000)]
ehea: make some functions and variables static

Some functions and variables in ehea are only used in their own file, so
they should be static. One particular function had a very generic name,
print_error_data.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agobrcmsmac: remove PCI suspend/resume from bcma driver
Linus Torvalds [Fri, 13 Jan 2012 22:58:42 +0000 (23:58 +0100)]
brcmsmac: remove PCI suspend/resume from bcma driver

The brcmsmac driver isn't a PCI driver any more, it's a bcma one.  The
PCI device has been resumed by the PCI driver (the generic PCI layer,
really), we should be resuming just our own driver state.

Also add pr_debug() calls to show that we now actually get the
suspend/resume events.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobcma: connect the bcma bus suspend/resume to the bcma driver suspend/resume
Linus Torvalds [Fri, 13 Jan 2012 22:58:41 +0000 (23:58 +0100)]
bcma: connect the bcma bus suspend/resume to the bcma driver suspend/resume

Now the low-level driver actually gets informed that it is getting suspended and resumed.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobcma: add stub for bcma_bus_suspend()
Linus Torvalds [Fri, 13 Jan 2012 22:58:40 +0000 (23:58 +0100)]
bcma: add stub for bcma_bus_suspend()

.. and connect it up with the pci host bcma driver.

Now, the next step is to connect those bcma bus-level suspend/resume
functions to the actual bcma device suspend resume functions.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobcma: convert suspend/resume to pm_ops
Linus Torvalds [Fri, 13 Jan 2012 22:58:39 +0000 (23:58 +0100)]
bcma: convert suspend/resume to pm_ops

.. and avoid doing the unnecessary PCI operations - the PCI layer will
do them for us.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agonetfilter: ipset: dumping error triggered removing references twice
Jozsef Kadlecsik [Sat, 14 Jan 2012 15:42:13 +0000 (16:42 +0100)]
netfilter: ipset: dumping error triggered removing references twice

If there was a dumping error in the middle, the set-specific variable was
not zeroed out and thus the 'done' function of the dumping wrongly tried
to release the already released reference of the set. The already released
reference was caught by __ip_set_put and triggered a kernel BUG message.
Reported by Jean-Philippe Menil.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
12 years agonetfilter: ipset: autoload set type modules safely
Jozsef Kadlecsik [Tue, 17 Jan 2012 09:39:05 +0000 (10:39 +0100)]
netfilter: ipset: autoload set type modules safely

Jan Engelhardt noticed when userspace requests a set type unknown
to the kernel, it can lead to a loop due to the unsafe type module
loading. The issue is fixed in this patch.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
12 years agomac80211: fix tx->skb NULL pointer dereference
Yoni Divinsky [Mon, 16 Jan 2012 13:18:59 +0000 (15:18 +0200)]
mac80211: fix tx->skb NULL pointer dereference

In function ieee80211_tx_h_encrypt the var info was
initialized from tx->skb, since the fucntion
is called after the function ieee80211_tx_h_fragment
tx->skb is not valid anymore.

Signed-off-by: Yoni Divinsky <yoni.divinsky@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agowireless: iwlwifi: iwl-scan.c: Fix build warning
Fabio Estevam [Mon, 16 Jan 2012 02:47:12 +0000 (00:47 -0200)]
wireless: iwlwifi: iwl-scan.c: Fix build warning

Fix the following build warning:

drivers/net/wireless/iwlwifi/iwl-scan.c: In function ‘iwlagn_request_scan’:
drivers/net/wireless/iwlwifi/iwl-scan.c:572: warning: ‘cmd_len’ may be used uninitialized in this function

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agoNet, mac80211: Fix resource leak in ieee80211_rx_h_mesh_fwding()
Jesper Juhl [Sat, 14 Jan 2012 20:52:17 +0000 (21:52 +0100)]
Net, mac80211: Fix resource leak in ieee80211_rx_h_mesh_fwding()

We may leak the 'fwd_skb' we skb_copy() in ieee80211_rx_h_mesh_fwding() if
we take the 'else' branch in the 'if' statement just below. If we take
that branch we'll end up returning from the function and since we've not
assigned 'fwd_skb' to anything at that point, we leak it when the variable
goes out of scope.

The simple fix seems to be to just kfree_skb(fwd_skb); just before we
return. That is what this patch does.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agoath9k_hw: fix interpretation of the rx KeyMiss flag
Felix Fietkau [Sat, 14 Jan 2012 14:08:34 +0000 (15:08 +0100)]
ath9k_hw: fix interpretation of the rx KeyMiss flag

Documentation states that the KeyMiss flag is only valid if RxFrameOK is
unset, however empirical evidence has shown that this is false.
When KeyMiss is set (and RxFrameOK is 1), the hardware passes a valid frame
which has not been decrypted. The driver then falsely marks the frame
as decrypted, and when using CCMP this corrupts the rx CCMP PN, leading
to connection hangs.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agobcma: invalidate the mapped core over suspend/resume
Rafał Miłecki [Fri, 13 Jan 2012 22:58:38 +0000 (23:58 +0100)]
bcma: invalidate the mapped core over suspend/resume

This clears the currently mapped core when suspending, to force
re-mapping after resume. Without that we were touching default core
registers believing some other core is mapped. Such a behaviour
resulted in lockups on some machines.

Cc: stable@vger.kernel.org
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agoMAINTAINERS: add b43 mailing list
Rafał Miłecki [Fri, 13 Jan 2012 21:55:06 +0000 (22:55 +0100)]
MAINTAINERS: add b43 mailing list

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agoMAINTAINERS: move BCMA to keep the list sorted
Rafał Miłecki [Fri, 13 Jan 2012 21:55:05 +0000 (22:55 +0100)]
MAINTAINERS: move BCMA to keep the list sorted

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agonetfilter: revert user-space expectation helper support
Pablo Neira Ayuso [Sun, 15 Jan 2012 15:57:12 +0000 (16:57 +0100)]
netfilter: revert user-space expectation helper support

This patch partially reverts:
3d058d7 netfilter: rework user-space expectation helper support
that was applied during the 3.2 development cycle.

After this patch, the tree remains just like before patch bc01bef,
that initially added the preliminary infrastructure.

I decided to partially revert this patch because the approach
that I proposed to resolve this problem is broken in NAT setups.
Moreover, a new infrastructure will be submitted for the 3.3.x
development cycle that resolve the existing issues while
providing a neat solution.

Since nobody has been seriously using this infrastructure in
user-space, the removal of this feature should affect any know
FOSS project (to my knowledge).

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
12 years agonetfilter: xt_hashlimit: fix unused variable warning if IPv6 disabled
Stephen Rothwell [Wed, 11 Jan 2012 00:52:17 +0000 (11:52 +1100)]
netfilter: xt_hashlimit: fix unused variable warning if IPv6 disabled

Fixes this warning when CONFIG_IP6_NF_IPTABLES is not enabled:

net/netfilter/xt_hashlimit.c: In function ‘hashlimit_init_dst’:
net/netfilter/xt_hashlimit.c:448:9: warning: unused variable ‘frag_off’ [-Wunused-variable]

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
12 years agomac80211: fix no-op authorized transitions
Johannes Berg [Fri, 13 Jan 2012 13:17:59 +0000 (14:17 +0100)]
mac80211: fix no-op authorized transitions

When userspace attempts to authorize a station
that is already authorized, nothing happens as
you'd expect. Similarly, when it unauthorizes
a station that is associated, nothing happens.

However, when it unauthorizes a station that
isn't even associated yet, we erroneously try
to move the station to associated. This seems
to happen occasionally as a result of a race
when wpa_supplicant attempts to unauthorize
the port in managed mode. Particularly with my
new patches to keep stations, it can then move
a station into ASSOCIATED state before we have
really associated, which is really confusing.

I introduced this bug in
"mac80211: refactor station state transitions"

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agort2800pci: fix spurious interrupts generation
Stanislaw Gruszka [Fri, 13 Jan 2012 11:59:32 +0000 (12:59 +0100)]
rt2800pci: fix spurious interrupts generation

Same devices can generate interrupt without properly setting bit in
INT_SOURCE_CSR register (spurious interrupt), what will cause IRQ line
will be disabled by interrupts controller driver.

We discovered that clearing INT_MASK_CSR stops such behaviour. We
previously first read that register, and then clear all know interrupt
sources bits and do not touch reserved bits. After this patch, we write
to all register content (I believe writing to reserved bits on that
register will not cause any problems, I tested that on my rt2800pci
device).

This fix very bad performance problem, practically making device
unusable (since worked without interrupts), reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=658451

We previously tried to workaround that issue in commit
4ba7d9997869d25bd223dea7536fc1ce9fab3b3b "rt2800pci: handle spurious
interrupts", but it was reverted in commit
82e5fc2a34fa9ffea38f00c4066b7e600a0ca5e6
as thing, that will prevent to detect real spurious interrupts.

Reported-and-tested-by: Amir Hedayaty <hedayaty@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agoipw2x00: signedness bug handling frame length
Dan Carpenter [Thu, 12 Jan 2012 06:34:50 +0000 (09:34 +0300)]
ipw2x00: signedness bug handling frame length

This is basically just a cleanup.  Large positive numbers get counted as
negative but then get implicitly cast to positive again for the checks
that matter.

This does make a small difference in ipw_handle_promiscuous_rx() when we
test "if (unlikely((len + IPW_RX_FRAME_SIZE) > skb_tailroom(rxb->skb)))"
It should return there, but we don't return until a couple lines later
when we test "if (len > IPW_RX_BUF_SIZE - sizeof(struct ipw_rt_hdr)) {".
The difference is that in the second test the sizeof() means that there
is an implied cast to unsigned.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agowireless: b43: fix Oops on card eject during transfer
Guennadi Liakhovetski [Fri, 6 Jan 2012 11:58:16 +0000 (12:58 +0100)]
wireless: b43: fix Oops on card eject during transfer

An Oops has once been observed, when the SDIO card had been ejected during
IO. The PC value shows, that the dev pointer in b43_op_stop() was NULL.

(I moved the NULL check before the lock, based upon a suggestion from
Julian Calaby <julian.calaby@gmail.com>. -- JWL)

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
12 years agovhost-net: add module alias (v2.1)
stephen hemminger [Wed, 11 Jan 2012 19:30:38 +0000 (19:30 +0000)]
vhost-net: add module alias (v2.1)

By adding some module aliases, programs (or users) won't have to explicitly
call modprobe. Vhost-net will always be available if built into the kernel.
It does require assigning a permanent minor number for depmod to work.

Also:
  - use C99 style initialization.
  - add missing entry in documentation for loop-control

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoipv6: release idev when ip6_neigh_lookup failed in icmp6_dst_alloc
RongQing.Li [Thu, 12 Jan 2012 22:33:46 +0000 (22:33 +0000)]
ipv6: release idev when ip6_neigh_lookup failed in icmp6_dst_alloc

release idev when ip6_neigh_lookup failed in icmp6_dst_alloc

Signed-off-by: RongQing.Li <roy.qing.li@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
12 years agoMerge branch 'akpm' (aka "Andrew's patch-bomb, take two")
Linus Torvalds [Fri, 13 Jan 2012 04:42:54 +0000 (20:42 -0800)]
Merge branch 'akpm' (aka "Andrew's patch-bomb, take two")

Andrew explains:

 - various misc stuff

 - Most of the rest of MM: memcg, threaded hugepages, others.

 - cpumask

 - kexec

 - kdump

 - some direct-io performance tweaking

 - radix-tree optimisations

 - new selftests code

   A note on this: often people will develop a new userspace-visible
   feature and will develop userspace code to exercise/test that
   feature.  Then they merge the patch and the selftest code dies.
   Sometimes we paste it into the changelog.  Sometimes the code gets
   thrown into Documentation/(!).

   This saddens me.  So this patch creates a bare-bones framework which
   will henceforth allow me to ask people to include their test apps in
   the kernel tree so we can keep them alive.  Then when people enhance
   or fix the feature, I can ask them to update the test app too.

   The infrastruture is terribly trivial at present - let's see how it
   evolves.

 - checkpoint/restart feature work.

   A note on this: this is a project by various mad Russians to perform
   c/r mainly from userspace, with various oddball helper code added
   into the kernel where the need is demonstrated.

   So rather than some large central lump of code, what we have is
   little bits and pieces popping up in various places which either
   expose something new or which permit something which is normally
   kernel-private to be modified.

   The overall project is an ongoing thing.  I've judged that the size
   and scope of the thing means that we're more likely to be successful
   with it if we integrate the support into mainline piecemeal rather
   than allowing it all to develop out-of-tree.

   However I'm less confident than the developers that it will all
   eventually work! So what I'm asking them to do is to wrap each piece
   of new code inside CONFIG_CHECKPOINT_RESTORE.  So if it all
   eventually comes to tears and the project as a whole fails, it should
   be a simple matter to go through and delete all trace of it.

This lot pretty much wraps up the -rc1 merge for me.

* akpm: (96 commits)
  unlzo: fix input buffer free
  ramoops: update parameters only after successful init
  ramoops: fix use of rounddown_pow_of_two()
  c/r: prctl: add PR_SET_MM codes to set up mm_struct entries
  c/r: procfs: add start_data, end_data, start_brk members to /proc/$pid/stat v4
  c/r: introduce CHECKPOINT_RESTORE symbol
  selftests: new x86 breakpoints selftest
  selftests: new very basic kernel selftests directory
  radix_tree: take radix_tree_path off stack
  radix_tree: remove radix_tree_indirect_to_ptr()
  dio: optimize cache misses in the submission path
  vfs: cache request_queue in struct block_device
  fs/direct-io.c: calculate fs_count correctly in get_more_blocks()
  drivers/parport/parport_pc.c: fix warnings
  panic: don't print redundant backtraces on oops
  sysctl: add the kernel.ns_last_pid control
  kdump: add udev events for memory online/offline
  include/linux/crash_dump.h needs elf.h
  kdump: fix crash_kexec()/smp_send_stop() race in panic()
  kdump: crashk_res init check for /sys/kernel/kexec_crash_size
  ...

12 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Fri, 13 Jan 2012 04:30:02 +0000 (20:30 -0800)]
Merge git://git./linux/kernel/git/davem/net

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
  pptp: Accept packet with seq zero
  RDS: Remove some unused iWARP code
  net: fsl: fec: handle 10Mbps speed in RMII mode
  drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c: add missing iounmap
  drivers/net/ethernet/tundra/tsi108_eth.c: add missing iounmap
  ksz884x: fix mtu for VLAN
  net_sched: sfq: add optional RED on top of SFQ
  dp83640: Fix NOHZ local_softirq_pending 08 warning
  gianfar: Fix invalid TX frames returned on error queue when time stamping
  gianfar: Fix missing sock reference when processing TX time stamps
  phylib: introduce mdiobus_alloc_size()
  net: decrement memcg jump label when limit, not usage, is changed
  net: reintroduce missing rcu_assign_pointer() calls
  inet_diag: Rename inet_diag_req_compat into inet_diag_req
  inet_diag: Rename inet_diag_req into inet_diag_req_v2
  bond_alb: don't disable softirq under bond_alb_xmit
  mac80211: fix rx->key NULL pointer dereference in promiscuous mode
  nl80211: fix old station flags compatibility
  mdio-octeon: use an unique MDIO bus name.
  mdio-gpio: use an unique MDIO bus name.
  ...

12 years agounlzo: fix input buffer free
Sascha Hauer [Fri, 13 Jan 2012 01:21:01 +0000 (17:21 -0800)]
unlzo: fix input buffer free

unlzo modifies the pointer to in_buf, so we have to free the original
buffer, not the modified pointer.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoramoops: update parameters only after successful init
Kees Cook [Fri, 13 Jan 2012 01:20:59 +0000 (17:20 -0800)]
ramoops: update parameters only after successful init

If a platform device exists on the system, but ramoops fails to attach to
it, the module parameters are overridden before ramoops can fall back and
try to use passed module parameters.  Move update to end of init routine.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Cc: Sergiu Iordache <sergiu@chromium.org>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoramoops: fix use of rounddown_pow_of_two()
Marco Stornelli [Fri, 13 Jan 2012 01:20:58 +0000 (17:20 -0800)]
ramoops: fix use of rounddown_pow_of_two()

The return value of rounddown_pow_of_two wasn't evaluated, so the
operation was a no-op.

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoc/r: prctl: add PR_SET_MM codes to set up mm_struct entries
Cyrill Gorcunov [Fri, 13 Jan 2012 01:20:55 +0000 (17:20 -0800)]
c/r: prctl: add PR_SET_MM codes to set up mm_struct entries

When we restore a task we need to set up text, data and data heap sizes
from userspace to the values a task had at checkpoint time.  This patch
adds auxilary prctl codes for that.

While most of them have a statistical nature (their values are involved
into calculation of /proc/<pid>/statm output) the start_brk and brk values
are used to compute an allowed size of program data segment expansion.
Which means an arbitrary changes of this values might be dangerous
operation.  So to restrict access the following requirements applied to
prctl calls:

 - The process has to have CAP_SYS_ADMIN capability granted.
 - For all opcodes except start_brk/brk members an appropriate
   VMA area must exist and should fit certain VMA flags,
   such as:
   - code segment must be executable but not writable;
   - data segment must not be executable.

start_brk/brk values must not intersect with data segment and must not
exceed RLIMIT_DATA resource limit.

Still the main guard is CAP_SYS_ADMIN capability check.

Note the kernel should be compiled with CONFIG_CHECKPOINT_RESTORE support
otherwise these prctl calls will return -EINVAL.

[akpm@linux-foundation.org: cache current->mm in a local, saving 200 bytes text]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoc/r: procfs: add start_data, end_data, start_brk members to /proc/$pid/stat v4
Cyrill Gorcunov [Fri, 13 Jan 2012 01:20:53 +0000 (17:20 -0800)]
c/r: procfs: add start_data, end_data, start_brk members to /proc/$pid/stat v4

The mm->start_code/end_code, mm->start_data/end_data, mm->start_brk are
involved into calculation of program text/data segment sizes (which might
be seen in /proc/<pid>/statm) and into brk() call final address.

For restore we need to know all these values.  While
mm->start_code/end_code already present in /proc/$pid/stat, the rest
members are not, so this patch brings them in.

The restore procedure of these members is addressed in another patch using
prctl().

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoc/r: introduce CHECKPOINT_RESTORE symbol
Cyrill Gorcunov [Fri, 13 Jan 2012 01:20:49 +0000 (17:20 -0800)]
c/r: introduce CHECKPOINT_RESTORE symbol

For checkpoint/restore we need auxilary features being compiled into the
kernel, such as additional prctl codes, /proc/<pid>/map_files and etc...
but same time these features are not mandatory for a regular kernel so
CHECKPOINT_RESTORE config symbol should bring a way to disable them all at
once if one wish to get rid of additional functionality.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoselftests: new x86 breakpoints selftest
Frederic Weisbecker [Fri, 13 Jan 2012 01:20:46 +0000 (17:20 -0800)]
selftests: new x86 breakpoints selftest

Bring a first selftest in the relevant directory.  This tests several
combinations of breakpoints and watchpoints in x86, as well as icebp traps
and int3 traps.  Given the amount of breakpoint regressions we raised
after we merged the generic breakpoint infrastructure, such selftest
became necessary and can still serve today as a basis for new patches that
touch the do_debug() path.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoselftests: new very basic kernel selftests directory
Frederic Weisbecker [Fri, 13 Jan 2012 01:20:44 +0000 (17:20 -0800)]
selftests: new very basic kernel selftests directory

Bring a new kernel selftests directory in tools/testing/selftests.  To
add a new selftest, create a subdirectory with the sources and a
makefile that creates a target named "run_test" then add the
subdirectory name to the TARGET var in tools/testing/selftests/Makefile
and tools/testing/selftests/run_tests script.

This can help centralizing and maintaining any useful selftest that
developers usually tend to let rust in peace on some random server.

Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoradix_tree: take radix_tree_path off stack
Hugh Dickins [Fri, 13 Jan 2012 01:20:41 +0000 (17:20 -0800)]
radix_tree: take radix_tree_path off stack

Down, down in the deepest depths of GFP_NOIO page reclaim, we have
shrink_page_list() calling __remove_mapping() calling __delete_from_
swap_cache() or __delete_from_page_cache().

You would not expect those to need much stack, but in fact they call
radix_tree_delete(): which declares a 192-byte radix_tree_path array on
its stack (to record the node,offsets it visits when descending, in case
it needs to ascend to update them).  And if any tag is still set [1],
that calls radix_tree_tag_clear(), which declares a further such
192-byte radix_tree_path array on the stack.  (At least we have
interrupts disabled here, so won't then be pushing registers too.)

That was probably a good choice when most users were 32-bit (array of
half the size), and adding fields to radix_tree_node would have bloated
it unnecessarily.  But nowadays many are 64-bit, and each
radix_tree_node contains a struct rcu_head, which is only used when
freeing; whereas the radix_tree_path info is only used for updating the
tree (deleting, clearing tags or setting tags if tagged) when a lock
must be held, of no interest when accessing the tree locklessly.

So add a parent pointer to the radix_tree_node, in union with the
rcu_head, and remove all uses of the radix_tree_path.  There would be
space in that union to save the offset when descending as before (we can
argue that a lock must already be held to exclude other users), but
recalculating it when ascending is both easy (a constant shift and a
constant mask) and uncommon, so it seems better just to do that.

Two little optimizations: no need to decrement height when descending,
adjusting shift is enough; and once radix_tree_tag_if_tagged() has set
tag on a node and its ancestors, it need not ascend from that node
again.

perf on the radix tree test harness reports radix_tree_insert() as 2%
slower (now having to set parent), but radix_tree_delete() 24% faster.
Surely that's an exaggeration from rtth's artificially low map shift 3,
but forcing it back to 6 still rates radix_tree_delete() 8% faster.

[1] Can a pagecache tag (dirty, writeback or towrite) actually still be
set at the time of radix_tree_delete()? Perhaps not if the filesystem is
well-behaved.  But although I've not tracked any stack overflow down to
this cause, I have observed a curious case in which a dirty tag is set
and left set on tmpfs: page migration's migrate_page_copy() happens to
use __set_page_dirty_nobuffers() to set PageDirty on the newpage, and
that sets PAGECACHE_TAG_DIRTY as a side-effect - harmless to a
filesystem which doesn't use tags, except for this stack depth issue.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nai Xia <nai.xia@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoradix_tree: remove radix_tree_indirect_to_ptr()
Xiao Guangrong [Fri, 13 Jan 2012 01:20:39 +0000 (17:20 -0800)]
radix_tree: remove radix_tree_indirect_to_ptr()

It is not used anymore, remove it

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agodio: optimize cache misses in the submission path
Andi Kleen [Fri, 13 Jan 2012 01:20:35 +0000 (17:20 -0800)]
dio: optimize cache misses in the submission path

Some investigation of a transaction processing workload showed that a
major consumer of cycles in __blockdev_direct_IO is the cache miss while
accessing the block size.  This is because it has to walk the chain from
block_dev to gendisk to queue.

The block size is needed early on to check alignment and sizes.  It's only
done if the check for the inode block size fails.  But the costly block
device state is unconditionally fetched.

- Reorganize the code to only fetch block dev state when actually
  needed.

Then do a prefetch on the block dev early on in the direct IO path.  This
is worth it, because there is substantial code run before we actually
touch the block dev now.

- I also added some unlikelies to make it clear the compiler that block
  device fetch code is not normally executed.

This gave a small, but measurable improvement on a large database
benchmark (about 0.3%)

[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: using prefetch requires including prefetch.h]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agovfs: cache request_queue in struct block_device
Andi Kleen [Fri, 13 Jan 2012 01:20:34 +0000 (17:20 -0800)]
vfs: cache request_queue in struct block_device

This makes it possible to get from the inode to the request_queue with one
less cache miss.  Used in followon optimization.

The livetime of the pointer is the same as the gendisk.

This assumes that the queue will always stay the same in the gendisk while
it's visible to block_devices.  I think that's safe correct?

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agofs/direct-io.c: calculate fs_count correctly in get_more_blocks()
Tao Ma [Fri, 13 Jan 2012 01:20:33 +0000 (17:20 -0800)]
fs/direct-io.c: calculate fs_count correctly in get_more_blocks()

In get_more_blocks(), we use dio_count to calcuate fs_count and do some
tricky things to increase fs_count if dio_count isn't aligned.  But
actually it still has some corner cases that can't be coverd.  See the
following example:

dio_write foo -s 1024 -w 4096

(direct write 4096 bytes at offset 1024).  The same goes if the offset
isn't aligned to fs_blocksize.

In this case, the old calculation counts fs_count to be 1, but actually we
will write into 2 different blocks (if fs_blocksize=4096).  The old code
just works, since it will call get_block twice (and may have to allocate
and create extents twice for filesystems like ext4).  So we'd better call
get_block just once with the proper fs_count.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agodrivers/parport/parport_pc.c: fix warnings
Andrew Morton [Fri, 13 Jan 2012 01:20:32 +0000 (17:20 -0800)]
drivers/parport/parport_pc.c: fix warnings

drivers/parport/parport_pc.c: In function '__check_irq':
drivers/parport/parport_pc.c:3415: warning: return from incompatible pointer type
drivers/parport/parport_pc.c: In function '__check_dma':
drivers/parport/parport_pc.c:3417: warning: return from incompatible pointer type

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agopanic: don't print redundant backtraces on oops
Andi Kleen [Fri, 13 Jan 2012 01:20:30 +0000 (17:20 -0800)]
panic: don't print redundant backtraces on oops

When an oops causes a panic and panic prints another backtrace it's pretty
common to have the original oops data be scrolled away on a 80x50 screen.

The second backtrace is quite redundant and not needed anyways.

So don't print the panic backtrace when oops_in_progress is true.

[akpm@linux-foundation.org: add comment]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agosysctl: add the kernel.ns_last_pid control
Pavel Emelyanov [Fri, 13 Jan 2012 01:20:27 +0000 (17:20 -0800)]
sysctl: add the kernel.ns_last_pid control

The sysctl works on the current task's pid namespace, getting and setting
its last_pid field.

Writing is allowed for CAP_SYS_ADMIN-capable tasks thus making it possible
to create a task with desired pid value.  This ability is required badly
for the checkpoint/restore in userspace.

This approach suits all the parties for now.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agokdump: add udev events for memory online/offline
Michael Holzheu [Fri, 13 Jan 2012 01:20:23 +0000 (17:20 -0800)]
kdump: add udev events for memory online/offline

Currently no udev events for memory hotplug "online" and "offline" are
generated:

  # udevadm monitor
  # echo offline > /sys/devices/system/memory/memory4/state
  ==> No event

When kdump is loaded, kexec detects the current memory configuration and
stores it in the pre-allocated ELF core header.  Therefore, for kdump it
is necessary to reload the kdump kernel with kexec when the memory
configuration changes (e.g.  for online/offline hotplug memory).

In order to do this automatically, udev rules should be used.  This kernel
patch adds udev events for "online" and "offline".  Together with this
kernel patch, the following udev rules for online/offline have to be added
to "/etc/udev/rules.d/98-kexec.rules":

  SUBSYSTEM=="memory", ACTION=="online", PROGRAM="/etc/init.d/kdump restart"
  SUBSYSTEM=="memory", ACTION=="offline", PROGRAM="/etc/init.d/kdump restart"

[sfr@canb.auug.org.au: fixups for class to subsystem conversion]
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoinclude/linux/crash_dump.h needs elf.h
Fabio Estevam [Fri, 13 Jan 2012 01:20:20 +0000 (17:20 -0800)]
include/linux/crash_dump.h needs elf.h

Building an ARM target we get the following warnings:

  CC      arch/arm/kernel/setup.o
  In file included from arch/arm/kernel/setup.c:39:
  arch/arm/include/asm/elf.h:102:1: warning: "vmcore_elf64_check_arch" redefined
  In file included from arch/arm/kernel/setup.c:24:
  include/linux/crash_dump.h:30:1: warning: this is the location of the previous definition

Quoting Russell King:

"linux/crash_dump.h makes no attempt to include asm/elf.h, but it depends
on stuff in asm/elf.h to determine how stuff inside this file is defined
at parse time.

So, if asm/elf.h is included after linux/crash_dump.h or not at all, you
get a different result from the situation where asm/elf.h is included
before."

So add elf.h header to crash_dump.h to avoid this problem.

The original discussion about this can be found at:
http://www.spinics.net/lists/arm-kernel/msg154113.html

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: <stable@vger.kernel.org> [3.2.1]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agokdump: fix crash_kexec()/smp_send_stop() race in panic()
Michael Holzheu [Fri, 13 Jan 2012 01:20:18 +0000 (17:20 -0800)]
kdump: fix crash_kexec()/smp_send_stop() race in panic()

When two CPUs call panic at the same time there is a possible race
condition that can stop kdump.  The first CPU calls crash_kexec() and the
second CPU calls smp_send_stop() in panic() before crash_kexec() finished
on the first CPU.  So the second CPU stops the first CPU and therefore
kdump fails:

1st CPU:
  panic()->crash_kexec()->mutex_trylock(&kexec_mutex)-> do kdump

2nd CPU:
  panic()->crash_kexec()->kexec_mutex already held by 1st CPU
       ->smp_send_stop()-> stop 1st CPU (stop kdump)

This patch fixes the problem by introducing a spinlock in panic that
allows only one CPU to process crash_kexec() and the subsequent panic
code.

All other CPUs call the weak function panic_smp_self_stop() that stops the
CPU itself.  This function can be overloaded by architecture code.  For
example "tile" can use their lower-power "nap" instruction for that.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agokdump: crashk_res init check for /sys/kernel/kexec_crash_size
Michael Holzheu [Fri, 13 Jan 2012 01:20:15 +0000 (17:20 -0800)]
kdump: crashk_res init check for /sys/kernel/kexec_crash_size

Currently it is possible to set the crash_size via the sysfs
/sys/kernel/kexec_crash_size even if no crash kernel memory has been
defined with the "crashkernel" parameter.  In this case "crashk_res" is
not initialized and crashk_res.start = crashk_res.end = 0.  Unfortunately
resource_size(&crashk_res) returns 1 in this case.  This breaks the s390
implementation of crash_(un)map_reserved_pages().

To fix the problem the correct "old_size" is now calculated in
crash_shrink_memory().  "old_size is set to "0" if crashk_res is not
initialized.  With this change crash_shrink_memory() will do nothing, when
"crashk_res" is not initialized.  It will return "0" for "echo 0 >
/sys/kernel/kexec_crash_size" and -EINVAL for "echo [not zero] >
/sys/kernel/kexec_crash_size".

In addition to that this patch also simplifies the "ret = -EINVAL" vs.
"ret = 0" logic as suggested by Simon Horman.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agokdump: add missing RAM resource in crash_shrink_memory()
Michael Holzheu [Fri, 13 Jan 2012 01:20:14 +0000 (17:20 -0800)]
kdump: add missing RAM resource in crash_shrink_memory()

When shrinking crashkernel memory using /sys/kernel/kexec_crash_size for
the newly added memory no RAM resource is created at the moment.

Example:

  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
  c0000000-cfffffff : Crash kernel
  d0000000-ffffffff : System RAM

  $ echo 0 > /sys/kernel/kexec_crash_size
  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
                                   <<-- here is System RAM missing
  d0000000-ffffffff : System RAM

One result of this bug is that the memory chunk can never be set offline
using memory hotplug.  With this patch I insert a new "System RAM"
resource for the released memory.  Then the upper example looks like the
following:

  $ echo 0 > /sys/kernel/kexec_crash_size
  $ cat /proc/iomem
  00000000-bfffffff : System RAM
    00000000-005b7ac3 : Kernel code
    005b7ac4-009743bf : Kernel data
    009bb000-00a85c33 : Kernel bss
  c0000000-cfffffff : System RAM   <<-- new rescoure
  d0000000-ffffffff : System RAM

And now I can set chunk c0000000-cfffffff offline.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agokexec: remove KMSG_DUMP_KEXEC
WANG Cong [Fri, 13 Jan 2012 01:20:11 +0000 (17:20 -0800)]
kexec: remove KMSG_DUMP_KEXEC

KMSG_DUMP_KEXEC is useless because we already save kernel messages inside
/proc/vmcore, and it is unsafe to allow modules to do other stuffs in a
crash dump scenario.

[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agocpumask: update setup_node_to_cpumask_map() comments
Wanlong Gao [Fri, 13 Jan 2012 01:20:09 +0000 (17:20 -0800)]
cpumask: update setup_node_to_cpumask_map() comments

node_to_cpumask() has been replaced by cpumask_of_node(), and wholly
removed since commit 29c337a0 ("cpumask: remove obsolete node_to_cpumask
now everyone uses cpumask_of_node").

So update the comments for setup_node_to_cpumask_map().

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm/vmalloc.c: eliminate extra loop in pcpu_get_vm_areas error path
Kautuk Consul [Fri, 13 Jan 2012 01:20:08 +0000 (17:20 -0800)]
mm/vmalloc.c: eliminate extra loop in pcpu_get_vm_areas error path

If either of the vas or vms arrays are not properly kzalloced, then the
code jumps to the err_free label.

The err_free label runs a loop to check and free each of the array members
of the vas and vms arrays which is not required for this situation as none
of the array members have been allocated till this point.

Eliminate the extra loop we have to go through by introducing a new label
err_free2 and then jumping to it.

[akpm@linux-foundation.org: remove now-unneeded tests]
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: rearrange putback_inactive_pages
Hugh Dickins [Fri, 13 Jan 2012 01:20:07 +0000 (17:20 -0800)]
mm: rearrange putback_inactive_pages

There is sometimes confusion between the global putback_lru_pages() in
migrate.c and the static putback_lru_pages() in vmscan.c: rename the
latter putback_inactive_pages(): it helps shrink_inactive_list() rather as
move_active_pages_to_lru() helps shrink_active_list().

Remove unused scan_control arg from putback_inactive_pages() and from
update_isolated_counts().  Move clear_active_flags() inside
update_isolated_counts().  Move NR_ISOLATED accounting up into
shrink_inactive_list() itself, so the balance is clearer.

Do the spin_lock_irq() before calling putback_inactive_pages() and
spin_unlock_irq() after return from it, so that it better matches
update_isolated_counts() and move_active_pages_to_lru().

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: remove isolate_pages()
Hugh Dickins [Fri, 13 Jan 2012 01:20:06 +0000 (17:20 -0800)]
mm: remove isolate_pages()

The isolate_pages() level in vmscan.c offers little but indirection: merge
it into isolate_lru_pages() as the compiler does, and use the names
nr_to_scan and nr_scanned in each case.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: remove del_page_from_lru, add page_off_lru
Hugh Dickins [Fri, 13 Jan 2012 01:20:04 +0000 (17:20 -0800)]
mm: remove del_page_from_lru, add page_off_lru

del_page_from_lru() repeats del_page_from_lru_list(), also working out
which LRU the page was on, clearing the relevant bits.  Decouple those
functions: remove del_page_from_lru() and add page_off_lru().

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: enum lru_list lru
Hugh Dickins [Fri, 13 Jan 2012 01:20:01 +0000 (17:20 -0800)]
mm: enum lru_list lru

Mostly we use "enum lru_list lru": change those few "l"s to "lru"s.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: no blank line after EXPORT_SYMBOL in swap.c
Hugh Dickins [Fri, 13 Jan 2012 01:20:00 +0000 (17:20 -0800)]
mm: no blank line after EXPORT_SYMBOL in swap.c

checkpatch rightly protests

  WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable

so fix the five offenders in mm/swap.c.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: fewer underscores in ____pagevec_lru_add
Hugh Dickins [Fri, 13 Jan 2012 01:19:58 +0000 (17:19 -0800)]
mm: fewer underscores in ____pagevec_lru_add

What's so special about ____pagevec_lru_add() that it needs four leading
underscores?  Nothing, it just helped to distinguish from
__pagevec_lru_add() in 2.6.28 development.  Cut two leading underscores.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: take pagevecs off reclaim stack
Hugh Dickins [Fri, 13 Jan 2012 01:19:56 +0000 (17:19 -0800)]
mm: take pagevecs off reclaim stack

Replace pagevecs in putback_lru_pages() and move_active_pages_to_lru()
by lists of pages_to_free: then apply Konstantin Khlebnikov's
free_hot_cold_page_list() to them instead of pagevec_release().

Which simplifies the flow (no need to drop and retake lock whenever
pagevec fills up) and reduces stale addresses in stack backtraces
(which often showed through the pagevecs); but more importantly,
removes another 120 bytes from the deepest stacks in page reclaim.
Although I've not recently seen an actual stack overflow here with
a vanilla kernel, move_active_pages_to_lru() has often featured in
deep backtraces.

However, free_hot_cold_page_list() does not handle compound pages
(nor need it: a Transparent HugePage would have been split by the
time it reaches the call in shrink_page_list()), but it is possible
for putback_lru_pages() or move_active_pages_to_lru() to be left
holding the last reference on a THP, so must exclude the unlikely
compound case before putting on pages_to_free.

Remove pagevec_strip(), its work now done in move_active_pages_to_lru().
The pagevec in scan_mapping_unevictable_pages() remains in mm/vmscan.c,
but that is never on the reclaim path, and cannot be replaced by a list.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomemcg: fix mem_cgroup_print_bad_page
Hugh Dickins [Fri, 13 Jan 2012 01:19:54 +0000 (17:19 -0800)]
memcg: fix mem_cgroup_print_bad_page

If DEBUG_VM, mem_cgroup_print_bad_page() is called whenever bad_page()
shows a "Bad page state" message, removes page from circulation, adds a
taint and continues.  This is at a very low level, often when a spinlock
is held (sometimes when page table lock is held, for example).

We want to recover from this badness, not make it worse: we must not
kmalloc memory here, we must not do a cgroup path lookup via dubious
pointers.  No doubt that code was useful to debug a particular case at one
time, and may be again, but take it out of the mainline kernel.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomemcg: fix split_huge_page_refcounts()
Hugh Dickins [Fri, 13 Jan 2012 01:19:52 +0000 (17:19 -0800)]
memcg: fix split_huge_page_refcounts()

This patch started off as a cleanup: __split_huge_page_refcounts() has to
cope with two scenarios, when the hugepage being split is already on LRU,
and when it is not; but why does it have to split that accounting across
three different sites?  Consolidate it in lru_add_page_tail(), handling
evictable and unevictable alike, and use standard add_page_to_lru_list()
when accounting is needed (when the head is not yet on LRU).

But a recent regression in -next, I guess the removal of PageCgroupAcctLRU
test from mem_cgroup_split_huge_fixup(), makes this now a necessary fix:
under load, the MEM_CGROUP_ZSTAT count was wrapping to a huge number,
messing up reclaim calculations and causing a freeze at rmdir of cgroup.

Add a VM_BUG_ON to mem_cgroup_lru_del_list() when we're about to wrap that
count - this has not been the only such incident.  Document that
lru_add_page_tail() is for Transparent HugePages by #ifdef around it.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: vmscan: check if reclaim should really abort even if compaction_ready() is true...
Mel Gorman [Fri, 13 Jan 2012 01:19:49 +0000 (17:19 -0800)]
mm: vmscan: check if reclaim should really abort even if compaction_ready() is true for one zone

If compaction can proceed for a given zone, shrink_zones() does not
reclaim any more pages from it.  After commit [e0c2327: vmscan: abort
reclaim/compaction if compaction can proceed], do_try_to_free_pages()
tries to finish as soon as possible once one zone can compact.

This was intended to prevent slabs being shrunk unnecessarily but there
are side-effects.  One is that a small zone that is ready for compaction
will abort reclaim even if the chances of successfully allocating a THP
from that zone is small.  It also means that reclaim can return too early
even though sc->nr_to_reclaim pages were not reclaimed.

This partially reverts the commit until it is proven that slabs are really
being shrunk unnecessarily but preserves the check to return 1 to avoid
OOM if reclaim was aborted prematurely.

[aarcange@redhat.com: This patch replaces a revert from Andrea]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: vmscan: when reclaiming for compaction, ensure there are sufficient free pages...
Mel Gorman [Fri, 13 Jan 2012 01:19:45 +0000 (17:19 -0800)]
mm: vmscan: when reclaiming for compaction, ensure there are sufficient free pages available

In commit e0887c19 ("vmscan: limit direct reclaim for higher order
allocations"), Rik noted that reclaim was too aggressive when THP was
enabled.  In his initial patch he used the number of free pages to decide
if reclaim should abort for compaction.  My feedback was that reclaim and
compaction should be using the same logic when deciding if reclaim should
be aborted.

Unfortunately, this had the effect of reducing THP success rates when the
workload included something like streaming reads that continually
allocated pages.  The window during which compaction could run and return
a THP was too small.

This patch combines Rik's two patches together.  compaction_suitable() is
still used to decide if reclaim should be aborted to allow compaction is
used.  However, it will also ensure that there is a reasonable buffer of
free pages available.  This improves upon the THP allocation success rates
but bounds the number of pages that are freed for compaction.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel<riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: introduce sync-light migration for use by compaction
Mel Gorman [Fri, 13 Jan 2012 01:19:43 +0000 (17:19 -0800)]
mm: compaction: introduce sync-light migration for use by compaction

This patch adds a lightweight sync migrate operation MIGRATE_SYNC_LIGHT
mode that avoids writing back pages to backing storage.  Async compaction
maps to MIGRATE_ASYNC while sync compaction maps to MIGRATE_SYNC_LIGHT.
For other migrate_pages users such as memory hotplug, MIGRATE_SYNC is
used.

This avoids sync compaction stalling for an excessive length of time,
particularly when copying files to a USB stick where there might be a
large number of dirty pages backed by a filesystem that does not support
->writepages.

[aarcange@redhat.com: This patch is heavily based on Andrea's work]
[akpm@linux-foundation.org: fix fs/nfs/write.c build]
[akpm@linux-foundation.org: fix fs/btrfs/disk-io.c build]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: page allocator: do not call direct reclaim for THP allocations while compaction...
Mel Gorman [Fri, 13 Jan 2012 01:19:41 +0000 (17:19 -0800)]
mm: page allocator: do not call direct reclaim for THP allocations while compaction is deferred

If compaction is deferred, direct reclaim is used to try to free enough
pages for the allocation to succeed.  For small high-orders, this has a
reasonable chance of success.  However, if the caller has specified
__GFP_NO_KSWAPD to limit the disruption to the system, it makes more sense
to fail the allocation rather than stall the caller in direct reclaim.
This patch skips direct reclaim if compaction is deferred and the caller
specifies __GFP_NO_KSWAPD.

Async compaction only considers a subset of pages so it is possible for
compaction to be deferred prematurely and not enter direct reclaim even in
cases where it should.  To compensate for this, this patch also defers
compaction only if sync compaction failed.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Rik van Riel<riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: make isolate_lru_page() filter-aware again
Mel Gorman [Fri, 13 Jan 2012 01:19:38 +0000 (17:19 -0800)]
mm: compaction: make isolate_lru_page() filter-aware again

Commit 39deaf85 ("mm: compaction: make isolate_lru_page() filter-aware")
noted that compaction does not migrate dirty or writeback pages and that
is was meaningless to pick the page and re-add it to the LRU list.  This
had to be partially reverted because some dirty pages can be migrated by
compaction without blocking.

This patch updates "mm: compaction: make isolate_lru_page" by skipping
over pages that migration has no possibility of migrating to minimise LRU
disruption.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel<riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: determine if dirty pages can be migrated without blocking within...
Mel Gorman [Fri, 13 Jan 2012 01:19:34 +0000 (17:19 -0800)]
mm: compaction: determine if dirty pages can be migrated without blocking within ->migratepage

Asynchronous compaction is used when allocating transparent hugepages to
avoid blocking for long periods of time.  Due to reports of stalling,
there was a debate on disabling synchronous compaction but this severely
impacted allocation success rates.  Part of the reason was that many dirty
pages are skipped in asynchronous compaction by the following check;

if (PageDirty(page) && !sync &&
mapping->a_ops->migratepage != migrate_page)
rc = -EBUSY;

This skips over all mapping aops using buffer_migrate_page() even though
it is possible to migrate some of these pages without blocking.  This
patch updates the ->migratepage callback with a "sync" parameter.  It is
the responsibility of the callback to fail gracefully if migration would
block.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: vmscan: do not OOM if aborting reclaim to start compaction
Mel Gorman [Fri, 13 Jan 2012 01:19:33 +0000 (17:19 -0800)]
mm: vmscan: do not OOM if aborting reclaim to start compaction

During direct reclaim it is possible that reclaim will be aborted so that
compaction can be attempted to satisfy a high-order allocation.  If this
decision is made before any pages are reclaimed, it is possible that 0 is
returned to the page allocator potentially triggering an OOM.  This has
not been observed but it is a possibility so this patch addresses it.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: vmscan: check if we isolated a compound page during lumpy scan
Andrea Arcangeli [Fri, 13 Jan 2012 01:19:29 +0000 (17:19 -0800)]
mm: vmscan: check if we isolated a compound page during lumpy scan

Properly take into account if we isolated a compound page during the lumpy
scan in reclaim and skip over the tail pages when encountered.  This
corrects the values given to the tracepoint for number of lumpy pages
isolated and will avoid breaking the loop early if compound pages smaller
than the requested allocation size are requested.

[mgorman@suse.de: Updated changelog]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: use synchronous compaction for /proc/sys/vm/compact_memory
Mel Gorman [Fri, 13 Jan 2012 01:19:26 +0000 (17:19 -0800)]
mm: compaction: use synchronous compaction for /proc/sys/vm/compact_memory

When asynchronous compaction was introduced, the
/proc/sys/vm/compact_memory handler should have been updated to always use
synchronous compaction.  This did not happen so this patch addresses it.

The assumption is if a user writes to /proc/sys/vm/compact_memory, they
are willing for that process to stall.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: allow compaction to isolate dirty pages
Mel Gorman [Fri, 13 Jan 2012 01:19:22 +0000 (17:19 -0800)]
mm: compaction: allow compaction to isolate dirty pages

Short summary: There are severe stalls when a USB stick using VFAT is
used with THP enabled that are reduced by this series.  If you are
experiencing this problem, please test and report back and considering I
have seen complaints from openSUSE and Fedora users on this as well as a
few private mails, I'm guessing it's a widespread issue.  This is a new
type of USB-related stall because it is due to synchronous compaction
writing where as in the past the big problem was dirty pages reaching
the end of the LRU and being written by reclaim.

Am cc'ing Andrew this time and this series would replace
mm-do-not-stall-in-synchronous-compaction-for-thp-allocations.patch.
I'm also cc'ing Dave Jones as he might have merged that patch to Fedora
for wider testing and ideally it would be reverted and replaced by this
series.

That said, the later patches could really do with some review.  If this
series is not the answer then a new direction needs to be discussed
because as it is, the stalls are unacceptable as the results in this
leader show.

For testers that try backporting this to 3.1, it won't work because
there is a non-obvious dependency on not writing back pages in direct
reclaim so you need those patches too.

Changelog since V5
o Rebase to 3.2-rc5
o Tidy up the changelogs a bit

Changelog since V4
o Added reviewed-bys, credited Andrea properly for sync-light
o Allow dirty pages without mappings to be considered for migration
o Bound the number of pages freed for compaction
o Isolate PageReclaim pages on their own LRU list

This is against 3.2-rc5 and follows on from discussions on "mm: Do
not stall in synchronous compaction for THP allocations" and "[RFC
PATCH 0/5] Reduce compaction-related stalls". Initially, the proposed
patch eliminated stalls due to compaction which sometimes resulted in
user-visible interactivity problems on browsers by simply never using
sync compaction. The downside was that THP success allocation rates
were lower because dirty pages were not being migrated as reported by
Andrea. His approach at fixing this was nacked on the grounds that
it reverted fixes from Rik merged that reduced the amount of pages
reclaimed as it severely impacted his workloads performance.

This series attempts to reconcile the requirements of maximising THP
usage, without stalling in a user-visible fashion due to compaction
or cheating by reclaiming an excessive number of pages.

Patch 1 partially reverts commit 39deaf85 to allow migration to isolate
dirty pages. This is because migration can move some dirty
pages without blocking.

Patch 2 notes that the /proc/sys/vm/compact_memory handler is not using
synchronous compaction when it should be. This is unrelated
to the reported stalls but is worth fixing.

Patch 3 checks if we isolated a compound page during lumpy scan and
account for it properly. For the most part, this affects
tracing so it's unrelated to the stalls but worth fixing.

Patch 4 notes that it is possible to abort reclaim early for compaction
and return 0 to the page allocator potentially entering the
"may oom" path. This has not been observed in practice but
the rest of the series potentially makes it easier to happen.

Patch 5 adds a sync parameter to the migratepage callback and gives
the callback responsibility for migrating the page without
blocking if sync==false. For example, fallback_migrate_page
will not call writepage if sync==false. This increases the
number of pages that can be handled by asynchronous compaction
thereby reducing stalls.

Patch 6 restores filter-awareness to isolate_lru_page for migration.
In practice, it means that pages under writeback and pages
without a ->migratepage callback will not be isolated
for migration.

Patch 7 avoids calling direct reclaim if compaction is deferred but
makes sure that compaction is only deferred if sync
compaction was used.

Patch 8 introduces a sync-light migration mechanism that sync compaction
uses. The objective is to allow some stalls but to not call
->writepage which can lead to significant user-visible stalls.

Patch 9 notes that while we want to abort reclaim ASAP to allow
compation to go ahead that we leave a very small window of
opportunity for compaction to run. This patch allows more pages
to be freed by reclaim but bounds the number to a reasonable
level based on the high watermark on each zone.

Patch 10 allows slabs to be shrunk even after compaction_ready() is
true for one zone. This is to avoid a problem whereby a single
small zone can abort reclaim even though no pages have been
reclaimed and no suitably large zone is in a usable state.

Patch 11 fixes a problem with the rate of page scanning. As reclaim is
rarely stalling on pages under writeback it means that scan
rates are very high. This is particularly true for direct
reclaim which is not calling writepage. The vmstat figures
implied that much of this was busy work with PageReclaim pages
marked for immediate reclaim. This patch is a prototype that
moves these pages to their own LRU list.

This has been tested and other than 2 USB keys getting trashed,
nothing horrible fell out. That said, I am a bit unhappy with the
rescue logic in patch 11 but did not find a better way around it. It
does significantly reduce scan rates and System CPU time indicating
it is the right direction to take.

What is of critical importance is that stalls due to compaction
are massively reduced even though sync compaction was still
allowed. Testing from people complaining about stalls copying to USBs
with THP enabled are particularly welcome.

The following tests all involve THP usage and USB keys in some
way. Each test follows this type of pattern

1. Read from some fast fast storage, be it raw device or file. Each time
   the copy finishes, start again until the test ends
2. Write a large file to a filesystem on a USB stick. Each time the copy
   finishes, start again until the test ends
3. When memory is low, start an alloc process that creates a mapping
   the size of physical memory to stress THP allocation. This is the
   "real" part of the test and the part that is meant to trigger
   stalls when THP is enabled. Copying continues in the background.
4. Record the CPU usage and time to execute of the alloc process
5. Record the number of THP allocs and fallbacks as well as the number of THP
   pages in use a the end of the test just before alloc exited
6. Run the test 5 times to get an idea of variability
7. Between each run, sync is run and caches dropped and the test
   waits until nr_dirty is a small number to avoid interference
   or caching between iterations that would skew the figures.

The individual tests were then

writebackCPDeviceBasevfat
Disable THP, read from a raw device (sda), vfat on USB stick
writebackCPDeviceBaseext4
Disable THP, read from a raw device (sda), ext4 on USB stick
writebackCPDevicevfat
THP enabled, read from a raw device (sda), vfat on USB stick
writebackCPDeviceext4
THP enabled, read from a raw device (sda), ext4 on USB stick
writebackCPFilevfat
THP enabled, read from a file on fast storage and USB, both vfat
writebackCPFileext4
THP enabled, read from a file on fast storage and USB, both ext4

The kernels tested were

3.1 3.1
vanilla 3.2-rc5
freemore Patches 1-10
immediate Patches 1-11
andrea The 8 patches Andrea posted as a basis of comparison

The results are very long unfortunately. I'll start with the case
where we are not using THP at all

writebackCPDeviceBasevfat
                   3.1.0-vanilla         rc5-vanilla       freemore-v6r1        isolate-v6r1         andrea-v2r1
System Time         1.28 (    0.00%)   54.49 (-4143.46%)   48.63 (-3687.69%)    4.69 ( -265.11%)   51.88 (-3940.81%)
+/-                 0.06 (    0.00%)    2.45 (-4305.55%)    4.75 (-8430.57%)    7.46 (-13282.76%)    4.76 (-8440.70%)
User Time           0.09 (    0.00%)    0.05 (   40.91%)    0.06 (   29.55%)    0.07 (   15.91%)    0.06 (   27.27%)
+/-                 0.02 (    0.00%)    0.01 (   45.39%)    0.02 (   25.07%)    0.00 (   77.06%)    0.01 (   52.24%)
Elapsed Time      110.27 (    0.00%)   56.38 (   48.87%)   49.95 (   54.70%)   11.77 (   89.33%)   53.43 (   51.54%)
+/-                 7.33 (    0.00%)    3.77 (   48.61%)    4.94 (   32.63%)    6.71 (    8.50%)    4.76 (   35.03%)
THP Active          0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)
+/-                 0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)
Fault Alloc         0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)
+/-                 0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)
Fault Fallback      0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)
+/-                 0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)    0.00 (    0.00%)

The THP figures are obviously all 0 because THP was enabled. The
main thing to watch is the elapsed times and how they compare to
times when THP is enabled later. It's also important to note that
elapsed time is improved by this series as System CPu time is much
reduced.

writebackCPDevicevfat

                   3.1.0-vanilla         rc5-vanilla       freemore-v6r1        isolate-v6r1         andrea-v2r1
System Time         1.22 (    0.00%)   13.89 (-1040.72%)   46.40 (-3709.20%)    4.44 ( -264.37%)   47.37 (-3789.33%)
+/-                 0.06 (    0.00%)   22.82 (-37635.56%)    3.84 (-6249.44%)    6.48 (-10618.92%)    6.60
(-10818.53%)
User Time           0.06 (    0.00%)    0.06 (   -6.90%)    0.05 (   17.24%)    0.05 (   13.79%)    0.04 (   31.03%)
+/-                 0.01 (    0.00%)    0.01 (   33.33%)    0.01 (   33.33%)    0.01 (   39.14%)    0.01 (   25.46%)
Elapsed Time     10445.54 (    0.00%) 2249.92 (   78.46%)   70.06 (   99.33%)   16.59 (   99.84%)  472.43 (
95.48%)
+/-               643.98 (    0.00%)  811.62 (  -26.03%)   10.02 (   98.44%)    7.03 (   98.91%)   59.99 (   90.68%)
THP Active         15.60 (    0.00%)   35.20 (  225.64%)   65.00 (  416.67%)   70.80 (  453.85%)   62.20 (  398.72%)
+/-                18.48 (    0.00%)   51.29 (  277.59%)   15.99 (   86.52%)   37.91 (  205.18%)   22.02 (  119.18%)
Fault Alloc       121.80 (    0.00%)   76.60 (   62.89%)  155.40 (  127.59%)  181.20 (  148.77%)  286.60 (  235.30%)
+/-                73.51 (    0.00%)   61.11 (   83.12%)   34.89 (   47.46%)   31.88 (   43.36%)   68.13 (   92.68%)
Fault Fallback    881.20 (    0.00%)  926.60 (   -5.15%)  847.60 (    3.81%)  822.00 (    6.72%)  716.60 (   18.68%)
+/-                73.51 (    0.00%)   61.26 (   16.67%)   34.89 (   52.54%)   31.65 (   56.94%)   67.75 (    7.84%)
MMTests Statistics: duration
User/Sys Time Running Test (seconds)       3540.88   1945.37    716.04     64.97   1937.03
Total Elapsed Time (seconds)              52417.33  11425.90    501.02    230.95   2520.28

The first thing to note is the "Elapsed Time" for the vanilla kernels
of 2249 seconds versus 56 with THP disabled which might explain the
reports of USB stalls with THP enabled. Applying the patches brings
performance in line with THP-disabled performance while isolating
pages for immediate reclaim from the LRU cuts down System CPU time.

The "Fault Alloc" success rate figures are also improved. The vanilla
kernel only managed to allocate 76.6 pages on average over the course
of 5 iterations where as applying the series allocated 181.20 on
average albeit it is well within variance. It's worth noting that
applies the series at least descreases the amount of variance which
implies an improvement.

Andrea's series had a higher success rate for THP allocations but
at a severe cost to elapsed time which is still better than vanilla
but still much worse than disabling THP altogether. One can bring my
series close to Andrea's by removing this check

        /*
         * If compaction is deferred for high-order allocations, it is because
         * sync compaction recently failed. In this is the case and the caller
         * has requested the system not be heavily disrupted, fail the
         * allocation now instead of entering direct reclaim
         */
        if (deferred_compaction && (gfp_mask & __GFP_NO_KSWAPD))
                goto nopage;

I didn't include a patch that removed the above check because hurting
overall performance to improve the THP figure is not what the average
user wants. It's something to consider though if someone really wants
to maximise THP usage no matter what it does to the workload initially.

This is summary of vmstat figures from the same test.

                                       3.1.0-vanilla rc5-vanilla freemore-v6r1 isolate-v6r1 andrea-v2r1
Page Ins                                  3257266139  1111844061    17263623    10901575   161423219
Page Outs                                   81054922    30364312     3626530     3657687     8753730
Swap Ins                                        3294        2851        6560        4964        4592
Swap Outs                                     390073      528094      620197      790912      698285
Direct pages scanned                      1077581700  3024951463  1764930052   115140570  5901188831
Kswapd pages scanned                        34826043     7112868     2131265     1686942     1893966
Kswapd pages reclaimed                      28950067     4911036     1246044      966475     1497726
Direct pages reclaimed                     805148398   280167837     3623473     2215044    40809360
Kswapd efficiency                                83%         69%         58%         57%         79%
Kswapd velocity                              664.399     622.521    4253.852    7304.360     751.490
Direct efficiency                                74%          9%          0%          1%          0%
Direct velocity                            20557.737  264745.137 3522673.849  498551.938 2341481.435
Percentage direct scans                          96%         99%         99%         98%         99%
Page writes by reclaim                        722646      529174      620319      791018      699198
Page writes file                              332573        1080         122         106         913
Page writes anon                              390073      528094      620197      790912      698285
Page reclaim immediate                             0  2552514720  1635858848   111281140  5478375032
Page rescued immediate                             0           0           0       87848           0
Slabs scanned                                  23552       23552        9216        8192        9216
Direct inode steals                              231           0           0           0           0
Kswapd inode steals                                0           0           0           0           0
Kswapd skipped wait                            28076         786           0          61           6
THP fault alloc                                  609         383         753         906        1433
THP collapse alloc                                12           6           0           0           6
THP splits                                       536         211         456         593        1136
THP fault fallback                              4406        4633        4263        4110        3583
THP collapse fail                                120         127           0           0           4
Compaction stalls                               1810         728         623         779        3200
Compaction success                               196          53          60          80         123
Compaction failures                             1614         675         563         699        3077
Compaction pages moved                        193158       53545      243185      333457      226688
Compaction move failure                         9952        9396       16424       23676       45070

The main things to look at are

1. Page In/out figures are much reduced by the series.

2. Direct page scanning is incredibly high (264745.137 pages scanned
   per second on the vanilla kernel) but isolating PageReclaim pages
   on their own list reduces the number of pages scanned significantly.

3. The fact that "Page rescued immediate" is a positive number implies
   that we sometimes race removing pages from the LRU_IMMEDIATE list
   that need to be put back on a normal LRU but it happens only for
   0.07% of the pages marked for immediate reclaim.

writebackCPDeviceext4
                   3.1.0-vanilla         rc5-vanilla       freemore-v6r1        isolate-v6r1         andrea-v2r1
System Time         1.51 (    0.00%)    1.77 (  -17.66%)    1.46 (    2.92%)    1.15 (   23.77%)    1.89 (  -25.63%)
+/-                 0.27 (    0.00%)    0.67 ( -148.52%)    0.33 (  -22.76%)    0.30 (  -11.15%)    0.19 (   30.16%)
User Time           0.03 (    0.00%)    0.04 (  -37.50%)    0.05 (  -62.50%)    0.07 ( -112.50%)    0.04 (  -18.75%)
+/-                 0.01 (    0.00%)    0.02 ( -146.64%)    0.02 (  -97.91%)    0.02 (  -75.59%)    0.02 (  -63.30%)
Elapsed Time      124.93 (    0.00%)  114.49 (    8.36%)   96.77 (   22.55%)   27.48 (   78.00%)  205.70 (  -64.65%)
+/-                20.20 (    0.00%)   74.39 ( -268.34%)   59.88 ( -196.48%)    7.72 (   61.79%)   25.03 (  -23.95%)
THP Active        161.80 (    0.00%)   83.60 (   51.67%)  141.20 (   87.27%)   84.60 (   52.29%)   82.60 (   51.05%)
+/-                71.95 (    0.00%)   43.80 (   60.88%)   26.91 (   37.40%)   59.02 (   82.03%)   52.13 (   72.45%)
Fault Alloc       471.40 (    0.00%)  228.60 (   48.49%)  282.20 (   59.86%)  225.20 (   47.77%)  388.40 (   82.39%)
+/-                88.07 (    0.00%)   87.42 (   99.26%)   73.79 (   83.78%)  109.62 (  124.47%)   82.62 (   93.81%)
Fault Fallback    531.60 (    0.00%)  774.60 (  -45.71%)  720.80 (  -35.59%)  777.80 (  -46.31%)  614.80 (  -15.65%)
+/-                88.07 (    0.00%)   87.26 (    0.92%)   73.79 (   16.22%)  109.62 (  -24.47%)   82.29 (    6.56%)
MMTests Statistics: duration
User/Sys Time Running Test (seconds)         50.22     33.76     30.65     24.14    128.45
Total Elapsed Time (seconds)               1113.73   1132.19   1029.45    759.49   1707.26

Similar test but the USB stick is using ext4 instead of vfat. As
ext4 does not use writepage for migration, the large stalls due to
compaction when THP is enabled are not observed. Still, isolating
PageReclaim pages on their own list helped completion time largely
by reducing the number of pages scanned by direct reclaim although
time spend in congestion_wait could also be a factor.

Again, Andrea's series had far higher success rates for THP allocation
at the cost of elapsed time. I didn't look too closely but a quick
look at the vmstat figures tells me kswapd reclaimed 8 times more pages
than the patch series and direct reclaim reclaimed roughly three times
as many pages. It follows that if memory is aggressively reclaimed,
there will be more available for THP.

writebackCPFilevfat
                   3.1.0-vanilla         rc5-vanilla       freemore-v6r1        isolate-v6r1         andrea-v2r1
System Time         1.76 (    0.00%)   29.10 (-1555.52%)   46.01 (-2517.18%)    4.79 ( -172.35%)   54.89 (-3022.53%)
+/-                 0.14 (    0.00%)   25.61 (-18185.17%)    2.15 (-1434.83%)    6.60 (-4610.03%)    9.75
(-6863.76%)
User Time           0.05 (    0.00%)    0.07 (  -45.83%)    0.05 (   -4.17%)    0.06 (  -29.17%)    0.06 (  -16.67%)
+/-                 0.02 (    0.00%)    0.02 (   20.11%)    0.02 (   -3.14%)    0.01 (   31.58%)    0.01 (   47.41%)
Elapsed Time     22520.79 (    0.00%) 1082.85 (   95.19%)   73.30 (   99.67%)   32.43 (   99.86%)  291.84 (  98.70%)
+/-              7277.23 (    0.00%)  706.29 (   90.29%)   19.05 (   99.74%)   17.05 (   99.77%)  125.55 (   98.27%)
THP Active         83.80 (    0.00%)   12.80 (   15.27%)   15.60 (   18.62%)   13.00 (   15.51%)    0.80 (    0.95%)
+/-                66.81 (    0.00%)   20.19 (   30.22%)    5.92 (    8.86%)   15.06 (   22.54%)    1.17 (    1.75%)
Fault Alloc       171.00 (    0.00%)   67.80 (   39.65%)   97.40 (   56.96%)  125.60 (   73.45%)  133.00 (   77.78%)
+/-                82.91 (    0.00%)   30.69 (   37.02%)   53.91 (   65.02%)   55.05 (   66.40%)   21.19 (   25.56%)
Fault Fallback    832.00 (    0.00%)  935.20 (  -12.40%)  906.00 (   -8.89%)  877.40 (   -5.46%)  870.20 (   -4.59%)
+/-                82.91 (    0.00%)   30.69 (   62.98%)   54.01 (   34.86%)   55.05 (   33.60%)   20.91 (   74.78%)
MMTests Statistics: duration
User/Sys Time Running Test (seconds)       7229.81    928.42    704.52     80.68   1330.76
Total Elapsed Time (seconds)             112849.04   5618.69    571.11    360.54   1664.28

In this case, the test is reading/writing only from filesystems but as
it's vfat, it's slow due to calling writepage during compaction. Little
to observe really - the time to complete the test goes way down
with the series applied and THP allocation success rates go up in
comparison to 3.2-rc5.  The success rates are lower than 3.1.0 but
the elapsed time for that kernel is abysmal so it is not really a
sensible comparison.

As before, Andrea's series allocates more THPs at the cost of overall
performance.

writebackCPFileext4
                   3.1.0-vanilla         rc5-vanilla       freemore-v6r1        isolate-v6r1         andrea-v2r1
System Time         1.51 (    0.00%)    1.77 (  -17.66%)    1.46 (    2.92%)    1.15 (   23.77%)    1.89 (  -25.63%)
+/-                 0.27 (    0.00%)    0.67 ( -148.52%)    0.33 (  -22.76%)    0.30 (  -11.15%)    0.19 (   30.16%)
User Time           0.03 (    0.00%)    0.04 (  -37.50%)    0.05 (  -62.50%)    0.07 ( -112.50%)    0.04 (  -18.75%)
+/-                 0.01 (    0.00%)    0.02 ( -146.64%)    0.02 (  -97.91%)    0.02 (  -75.59%)    0.02 (  -63.30%)
Elapsed Time      124.93 (    0.00%)  114.49 (    8.36%)   96.77 (   22.55%)   27.48 (   78.00%)  205.70 (  -64.65%)
+/-                20.20 (    0.00%)   74.39 ( -268.34%)   59.88 ( -196.48%)    7.72 (   61.79%)   25.03 (  -23.95%)
THP Active        161.80 (    0.00%)   83.60 (   51.67%)  141.20 (   87.27%)   84.60 (   52.29%)   82.60 (   51.05%)
+/-                71.95 (    0.00%)   43.80 (   60.88%)   26.91 (   37.40%)   59.02 (   82.03%)   52.13 (   72.45%)
Fault Alloc       471.40 (    0.00%)  228.60 (   48.49%)  282.20 (   59.86%)  225.20 (   47.77%)  388.40 (   82.39%)
+/-                88.07 (    0.00%)   87.42 (   99.26%)   73.79 (   83.78%)  109.62 (  124.47%)   82.62 (   93.81%)
Fault Fallback    531.60 (    0.00%)  774.60 (  -45.71%)  720.80 (  -35.59%)  777.80 (  -46.31%)  614.80 (  -15.65%)
+/-                88.07 (    0.00%)   87.26 (    0.92%)   73.79 (   16.22%)  109.62 (  -24.47%)   82.29 (    6.56%)
MMTests Statistics: duration
User/Sys Time Running Test (seconds)         50.22     33.76     30.65     24.14    128.45
Total Elapsed Time (seconds)               1113.73   1132.19   1029.45    759.49   1707.26

Same type of story - elapsed times go down. In this case, allocation
success rates are roughtly the same. As before, Andrea's has higher
success rates but takes a lot longer.

Overall the series does reduce latencies and while the tests are
inherency racy as alloc competes with the cp processes, the variability
was included. The THP allocation rates are not as high as they could
be but that is because we would have to be more aggressive about
reclaim and compaction impacting overall performance.

This patch:

Commit 39deaf85 ("mm: compaction: make isolate_lru_page() filter-aware")
noted that compaction does not migrate dirty or writeback pages and that
is was meaningless to pick the page and re-add it to the LRU list.

What was missed during review is that asynchronous migration moves dirty
pages if their ->migratepage callback is migrate_page() because these can
be moved without blocking.  This potentially impacted hugepage allocation
success rates by a factor depending on how many dirty pages are in the
system.

This patch partially reverts 39deaf85 to allow migration to isolate dirty
pages again.  This increases how much compaction disrupts the LRU but that
is addressed later in the series.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andy Isaacson <adi@hexapodia.org>
Cc: Nai Xia <nai.xia@gmail.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agovmscan/trace: Add 'file' info to trace_mm_vmscan_lru_isolate()
Tao Ma [Fri, 13 Jan 2012 01:19:20 +0000 (17:19 -0800)]
vmscan/trace: Add 'file' info to trace_mm_vmscan_lru_isolate()

In trace_mm_vmscan_lru_isolate(), we don't output 'file' information to
the trace event and it is a bit inconvenient for the user to get the
real information(like pasted below).  mm_vmscan_lru_isolate:
isolate_mode=2 order=0 nr_requested=32 nr_scanned=32 nr_taken=32
contig_taken=0 contig_dirty=0 contig_failed=0

'active' can be obtained by analyzing mode(Thanks go to Minchan and
Mel), So this patch adds 'file' to the trace event and it now looks
like: mm_vmscan_lru_isolate: isolate_mode=2 order=0 nr_requested=32
nr_scanned=32 nr_taken=32 contig_taken=0 contig_dirty=0 contig_failed=0
file=0

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: improve order in lru list for split huge page
Shaohua Li [Fri, 13 Jan 2012 01:19:18 +0000 (17:19 -0800)]
thp: improve order in lru list for split huge page

Put the tail subpages of an isolated hugepage under splitting in the lru
reclaim head as they supposedly should be isolated too next.

Queues the subpages in physical order in the lru for non isolated
hugepages under splitting.  That might provide some theoretical cache
benefit to the buddy allocator later.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: add tlb_remove_pmd_tlb_entry
Shaohua Li [Fri, 13 Jan 2012 01:19:16 +0000 (17:19 -0800)]
thp: add tlb_remove_pmd_tlb_entry

We have tlb_remove_tlb_entry to indicate a pte tlb flush entry should be
flushed, but not a corresponding API for pmd entry.  This isn't a
problem so far because THP is only for x86 currently and tlb_flush()
under x86 will flush entire TLB.  But this is confusion and could be
missed if thp is ported to other arch.

Also convert tlb->need_flush = 1 to a VM_BUG_ON(!tlb->need_flush) in
__tlb_remove_page() as suggested by Andrea Arcangeli.  The
__tlb_remove_page() function is supposed to be called after
tlb_remove_xxx_tlb_entry() and we can catch any misuse.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>