GitHub/exynos8895/android_kernel_samsung_universal8895.git
19 years ago[PATCH] i386 io_apic.c: Memorize at bootup where the i8259 is connected
Eric W. Biederman [Sun, 30 Oct 2005 22:59:39 +0000 (14:59 -0800)]
[PATCH] i386 io_apic.c: Memorize at bootup where the i8259 is connected

Currently we attempt to restore virtual wire mode on reboot, which only
works if we can figure out where the i8259 is connected.  This is very
useful when we kexec another kernel and likely helpful when dealing with a
BIOS that make assumptions about how the system is setup.

Since the acpi MADT table does not provide the location where the i8259 is
connected we have to look at the hardware to figure it out.

Most systems have the i8259 connected the local apic of the cpu so won't be
affected but people running Opteron and some serverworks chipsets should be
able to use kexec now.

In addition this patch removes the hard coded assumption that the io_apic
that delivers isa interrups is always known to the kernel as io_apic 0.  As
there does not appear to be anything to guarantee that assumption is true.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] ES7000 platform update
Natalie.Protasevich@unisys.com [Sun, 30 Oct 2005 22:59:38 +0000 (14:59 -0800)]
[PATCH] ES7000 platform update

This is platform code update for ES7000: disables IRQ overrides for the
recent ES7000 (Rascal/Zorro), cleans up the compile warning.  The patch
only affects the ES7000 subarch.

Signed-off-by: <Natalie.Protasevich@unisys.com>
Acked-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: when L3 is present show its size in /proc/cpuinfo
Venkatesh Pallipadi [Sun, 30 Oct 2005 22:59:38 +0000 (14:59 -0800)]
[PATCH] x86: when L3 is present show its size in /proc/cpuinfo

The code that prints the cache size assumes that L3 always lives in chipset
and is shared across CPUs.  Which is not really true.

I think all the cachesizes reported by cpuid are in the processor itself.
The attached patch changes the code to reflect that.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] fixup bogus e820 entry with mem=
Dave Hansen [Sun, 30 Oct 2005 22:59:37 +0000 (14:59 -0800)]
[PATCH] fixup bogus e820 entry with mem=

This was reported because someone was getting oopses reading /proc/iomem.
It was tracked down to a zero-sized 'struct resource' entry which was
located right at 4GB.

You need two conditions to hit this bug: a BIOS E820_RAM area starting at
exactly the boundary where you specify mem= (to get a zero-sized entry),
and for the legacy_init_iomem_resources() loop to skip that resource (which
only happens at exactly 4G).

I think the killing zero-sized e820 entry is the easiest way to fix this.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] asus vt8235 router buggy bios workaround
aleksey_gorelov@phoenix.com [Sun, 30 Oct 2005 22:59:36 +0000 (14:59 -0800)]
[PATCH] asus vt8235 router buggy bios workaround

Hopefully fix http://bugzilla.kernel.org/show_bug.cgi?id=5235

Similar problem has been reported before here:
http://groups.google.com/group/linux.kernel/browse_thread/thread/def4ca19dbc3cd4/5cffbf349f2c87a4?tvc=2&q=Aleksey+Gorelov&hl=en#5cffbf349f2c87a4
and was related to bug in BIOS reporting 82C686 router compatible to 586.

I suspect BIOS on this board has similar issue: reports VT8235 router to be
compatible with 586 one - which is obviously not true.  Patch from the link
above has already incorporated in both 2.6 & 2.4 series, but might not work
in this particular case.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: bug fix in P6 Machine check initialization
Venkatesh Pallipadi [Sun, 30 Oct 2005 22:59:35 +0000 (14:59 -0800)]
[PATCH] x86: bug fix in P6 Machine check initialization

Make P6 MCA initialization code complaint with guidelines in IA-32 SDM
Vol3.  Bank 0 control register should not be set by OS and clear status
registers on all banks on reset.

This will prevent false MCE alarms on the systems that has some non-MCE
information left-over in MC0_STATUS on reboot.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: add an accessor function for getting the per-CPU gdt
Zachary Amsden [Sun, 30 Oct 2005 22:59:34 +0000 (14:59 -0800)]
[PATCH] x86: add an accessor function for getting the per-CPU gdt

Add an accessor function for getting the per-CPU gdt.  Callee must already
have the CPU.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: bogus tls from gdt
Zachary Amsden [Sun, 30 Oct 2005 22:59:33 +0000 (14:59 -0800)]
[PATCH] x86: bogus tls from gdt

The per-CPU initialization code is copying in bogus data into
thread->tls_array.  Note that it copies &per_cpu(cpu_gdt_table, cpu), not
&per_cpu(cpu_gdt_table, cpu)[GDT_ENTRY_TLS_MIN).  That is totally broken
and unnecessary.  Make the initialization explicitly NULL.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: hot plug CPU to support physical add of new processors
Natalie Protasevich [Sun, 30 Oct 2005 22:59:32 +0000 (14:59 -0800)]
[PATCH] x86: hot plug CPU to support physical add of new processors

The patch allows physical bring-up of new processors (not initially present
in the configuration) from facilities such as driver/utility implemented on
a platform.  The actual method of making processors available is up to the
platform implementation.

Signed-off-by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Zwane Mwaikambo <zwane@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] i386: little pgtable.h consolidation vs 2/3level
Paolo 'Blaisorblade' Giarrusso [Sun, 30 Oct 2005 22:59:31 +0000 (14:59 -0800)]
[PATCH] i386: little pgtable.h consolidation vs 2/3level

Join together some common functions (pmd_page{,_kernel}) over 2level and
3level pages.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] intel_cacheinfo: remove MAX_CACHE_LEAVES limit
Siddha, Suresh B [Sun, 30 Oct 2005 22:59:30 +0000 (14:59 -0800)]
[PATCH] intel_cacheinfo: remove MAX_CACHE_LEAVES limit

Initial internal version of Venki's cpuid(4) deterministic cache parameter
identification patch used static arrays of size MAX_CACHE_LEAVES.  Final patch
which made to the base used dynamic array allocation, with this
MAX_CACHE_LEAVES limit hunk still in place.

cpuid(4) already has a mechanism to find out the number of cache levels
implemented and there is no need for this hardcoded MAX_CACHE_LEAVES limit.

So remove the MAX_CACHE_LEAVES limit from the routine which calculates the
number of cache levels using cpuid(4)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: initialise tss->io_bitmap_owner to something
Bart Oldeman [Sun, 30 Oct 2005 22:59:29 +0000 (14:59 -0800)]
[PATCH] x86: initialise tss->io_bitmap_owner to something

There exists a field io_bitmap_owner in the TSS that is only checked, but
never set to anything else but NULL.

Signed-off-by: Bart Oldeman <bartoldeman@users.sourceforge.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] FPU context corrupted after resume
Shaohua Li [Sun, 30 Oct 2005 22:59:28 +0000 (14:59 -0800)]
[PATCH] FPU context corrupted after resume

mxcsr_feature_mask_init isn't needed in suspend/resume time (we can use
boot time mask).  And actually it's harmful, as it clear task's saved
fxsave in resume.  This bug is widely seen by users using zsh.

(akpm: my eyes.  Fixed some surrounding whitespace mess)

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] x86: cmpxchg improvements
Jan Beulich [Sun, 30 Oct 2005 22:59:27 +0000 (14:59 -0800)]
[PATCH] x86: cmpxchg improvements

This adjusts i386's cmpxchg patterns so that

- for word and long cmpxchg-es the compiler can utilize all possible
  registers

- cmpxchg8b gets disabled when the minimum specified hardware architectur
  doesn't support it (like was already happening for the byte, word, and
  long ones).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] i386 and x86_64 TSC set_cyc2ns_scale imprecision
Mathieu Desnoyers [Sun, 30 Oct 2005 22:59:25 +0000 (14:59 -0800)]
[PATCH] i386 and x86_64 TSC set_cyc2ns_scale imprecision

I just found out that some precision is unnecessarily lost in the
arch/i386/kernel/timers/timer_tsc.c:set_cyc2ns_scale function.  It uses a
cpu_mhz parameter when it could use a cpu_khz.  In the specific case of an
Intel P4 running at 3001.171 Mhz, the truncation to 3001 Mhz leads to an
imprecision of 19 microseconds per second : this is very sad for a timer with
nearly nanosecond accuracy.

Fix the x86_64 architecture too.

Cc: george anzinger <george@mvista.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] SELinux: remove unecessary size_t checks in selinuxfs
Davi Arnaut [Sun, 30 Oct 2005 22:59:24 +0000 (14:59 -0800)]
[PATCH] SELinux: remove unecessary size_t checks in selinuxfs

This patch removes a bunch of unecessary checks for (size_t < 0) in
selinuxfs.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] selinux-canonicalize-getxattr-fix
Andrew Morton [Sun, 30 Oct 2005 22:59:23 +0000 (14:59 -0800)]
[PATCH] selinux-canonicalize-getxattr-fix

security/selinux/hooks.c: In function `selinux_inode_getxattr':
security/selinux/hooks.c:2193: warning: unused variable `sbsec'

Cc: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] SELinux: canonicalize getxattr()
James Morris [Sun, 30 Oct 2005 22:59:22 +0000 (14:59 -0800)]
[PATCH] SELinux: canonicalize getxattr()

This patch allows SELinux to canonicalize the value returned from
getxattr() via the security_inode_getsecurity() hook, which is called after
the fs level getxattr() function.

The purpose of this is to allow the in-core security context for an inode
to override the on-disk value.  This could happen in cases such as
upgrading a system to a different labeling form (e.g.  standard SELinux to
MLS) without needing to do a full relabel of the filesystem.

In such cases, we want getxattr() to return the canonical security context
that the kernel is using rather than what is stored on disk.

The implementation hooks into the inode_getsecurity(), adding another
parameter to indicate the result of the preceding fs-level getxattr() call,
so that SELinux knows whether to compare a value obtained from disk with
the kernel value.

We also now allow getxattr() to work for mountpoint labeled filesystems
(i.e.  mount with option context=foo_t), as we are able to return the
kernel value to the user.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] SELinux: convert to kzalloc
James Morris [Sun, 30 Oct 2005 22:59:21 +0000 (14:59 -0800)]
[PATCH] SELinux: convert to kzalloc

This patch converts SELinux code from kmalloc/memset to the new kazalloc
unction.  On i386, this results in a text saving of over 1K.

Before:
text    data     bss     dec     hex filename
86319    4642   15236  106197   19ed5 security/selinux/built-in.o

After:
text    data     bss     dec     hex filename
85278    4642   15236  105156   19ac4 security/selinux/built-in.o

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] CONFIG_IA32
Brian Gerst [Sun, 30 Oct 2005 22:59:20 +0000 (14:59 -0800)]
[PATCH] CONFIG_IA32

Add CONFIG_X86_32 for i386.  This allows selecting options that only apply
to 32-bit systems.

(X86 && !X86_64) becomes X86_32
(X86 ||  X86_64) becomes X86

Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] Remove redundant configs.o
Brian Gerst [Sun, 30 Oct 2005 22:59:18 +0000 (14:59 -0800)]
[PATCH] Remove redundant configs.o

Since CONFIG_IKCONFIG_PROC already depends on CONFIG_IKCONFIG, adding
configs.o again is redundant.

Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years agoMerge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...
Linus Torvalds [Sun, 30 Oct 2005 22:47:58 +0000 (14:47 -0800)]
Merge branch 'upstream-linus' of /linux/kernel/git/jgarzik/libata-dev

19 years ago[PATCH] NFS: Remove unbalanced spin_unlock() calls from nfs_refresh_inode()
Trond Myklebust [Sun, 30 Oct 2005 22:38:25 +0000 (17:38 -0500)]
[PATCH] NFS: Remove unbalanced spin_unlock() calls from nfs_refresh_inode()

Doh!

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years agoFix PIIX4 SMB region size
Linus Torvalds [Sun, 30 Oct 2005 22:40:07 +0000 (14:40 -0800)]
Fix PIIX4 SMB region size

Petr Vandrovec correctly points out that the SMB region of the PIIX4 is
just 16 bytes, not 32.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[libata] use dev_printk() throughout drivers
Jeff Garzik [Sun, 30 Oct 2005 19:39:11 +0000 (14:39 -0500)]
[libata] use dev_printk() throughout drivers

A few drivers were not following the standard meme of printing out
their driver name and version at module load time; this is fixed
as well.

19 years ago[libata ata_piix] fix native mode probe, after recent updates
Jeff Garzik [Sun, 30 Oct 2005 12:57:31 +0000 (07:57 -0500)]
[libata ata_piix] fix native mode probe, after recent updates

19 years ago[libata ata_piix] use dev_printk() where appropriate
Jeff Garzik [Sun, 30 Oct 2005 11:42:18 +0000 (06:42 -0500)]
[libata ata_piix] use dev_printk() where appropriate

19 years ago[libata] fix legacy IDE probing
Jeff Garzik [Sun, 30 Oct 2005 11:41:29 +0000 (06:41 -0500)]
[libata] fix legacy IDE probing

ata_pci_init_one() receives an array of struct ata_port_info.  Recent
updates to the code had always obtained port information from
array element 0, rather than array element N.

Change to avoid hardcoding port_info[0], thereby restoring proper
hardware information to secondary legacy ports.

19 years ago[libata] change ata_qc_complete() to take error mask as second arg
Jeff Garzik [Sun, 30 Oct 2005 09:44:42 +0000 (04:44 -0500)]
[libata] change ata_qc_complete() to take error mask as second arg

The second argument to ata_qc_complete() was being used for two
purposes: communicate the ATA Status register to the completion
function, and indicate an error.  On legacy PCI IDE hardware, the latter
is often implicit in the former.  On more modern hardware, the driver
often completely emulated a Status register value, passing ATA_ERR as an
indication that something went wrong.

Now that previous code changes have eliminated the need to use drv_stat
arg to communicate the ATA Status register value, we can convert it to a
mask of possible error classes.

This will lead to more flexible error handling in the future.

19 years agoMerge branch 'master'
Jeff Garzik [Sun, 30 Oct 2005 06:56:31 +0000 (01:56 -0500)]
Merge branch 'master'

19 years agoMerge master.kernel.org:/pub/scm/linux/kernel/git/herbert/crypto-2.6
Linus Torvalds [Sun, 30 Oct 2005 04:48:06 +0000 (21:48 -0700)]
Merge /pub/scm/linux/kernel/git/herbert/crypto-2.6

19 years ago[PATCH] mm/filemap.c:filemap_populate(): move export.
Nikita Danilov [Sun, 30 Oct 2005 01:17:02 +0000 (18:17 -0700)]
[PATCH] mm/filemap.c:filemap_populate(): move export.

move EXPORT_SYMBOL(filemap_populate) to the proper place: just after
function itself: it's easy to miss that function is exported otherwise.

Signed-off-by: Nikita Danilov <nikita@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: wider use of for_each_*cpu()
John Hawkes [Sun, 30 Oct 2005 01:17:01 +0000 (18:17 -0700)]
[PATCH] mm: wider use of for_each_*cpu()

In 'mm' change the explicit use of a for-loop using NR_CPUS into the
general for_each_cpu() constructs.  This widens the scope of potential
future optimizations of the general constructs, as well as takes advantage
of the existing optimizations of first_cpu() and next_cpu(), which is
advantageous when the true CPU count is much smaller than NR_CPUS.

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] Remove policy contextualization from mbind
Christoph Lameter [Sun, 30 Oct 2005 01:17:00 +0000 (18:17 -0700)]
[PATCH] Remove policy contextualization from mbind

Policy contextualization is only useful for task based policies and not for
vma based policies.  It may be useful to define allowed nodes that are not
accessible from this thread because other threads may have access to these
nodes.  Without this patch strange memory policy situations may cause an
application to fail with out of memory.

Example:

Let's say we have two threads A and B that share the same address space and
a huge array computational array X.

Thread A is restricted by its cpuset to nodes 0 and 1 and thread B is
restricted by its cpuset to nodes 2 and 3.

Thread A now wants to restrict allocations to the first node and thus
applies a BIND policy on X to node 0 and 2.  The cpuset limits this to node
0.  Thus pages for X must be allocated on node 0 now.

Thread B now touches a page that has never been used in X and faults in a
page.  According to the BIND policy of the vma for X the page must be
allocated on page 0.  However, the cpuset of B does not allow allocation on
0 and 1.  Now the application fails in alloc_pages with out of memory.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] Implement sys_* do_* layering in the memory policy layer.
Christoph Lameter [Sun, 30 Oct 2005 01:16:59 +0000 (18:16 -0700)]
[PATCH] Implement sys_* do_* layering in the memory policy layer.

- Do a separation between do_xxx and sys_xxx functions. sys_xxx functions
  take variable sized bitmaps from user space as arguments. do_xxx functions
  take fixed sized nodemask_t as arguments and may be used from inside the
  kernel. Doing so simplifies the initialization code. There is no
  fs = kernel_ds assumption anymore.

- Split up get_nodes into get_nodes (which gets the node list) and
  contextualize_policy which restricts the nodes to those accessible
  to the task and updates cpusets.

- Add comments explaining limitations of bind policy

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug: ppc64 specific hot-add functions
Dave Hansen [Sun, 30 Oct 2005 01:16:58 +0000 (18:16 -0700)]
[PATCH] memory hotplug: ppc64 specific hot-add functions

Here is a set of ppc64 specific patches that at least allow
compilation/booting with the following configurations:

FLATMEM
SPARSEMEN
SPARSEMEM + MEMORY_HOTPLUG

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug: i386 addition functions
Dave Hansen [Sun, 30 Oct 2005 01:16:57 +0000 (18:16 -0700)]
[PATCH] memory hotplug: i386 addition functions

Adds the necessary for non-NUMA hot-add of highmem to an existing zone on
i386.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug: call setup_per_zone_pages_min after hotplug
Dave Hansen [Sun, 30 Oct 2005 01:16:56 +0000 (18:16 -0700)]
[PATCH] memory hotplug: call setup_per_zone_pages_min after hotplug

From: IWAMOTO Toshihiro <iwamoto@valinux.co.jp>
> I found the tests does not work well with Dave's patchset.
> I've found the followings:
>
>  - setup_per_zone_pages_min() calls should be added in
>     capture_page_range() and online_pages()
>  - lru_add_drain() should be called before try_to_migrate_pages()

The following patch deals with the first item.

Signed-off-by: IWAMOTO Toshihiro <iwamoto@valinux.co.jp>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug: move section_mem_map alloc to sparse.c
Dave Hansen [Sun, 30 Oct 2005 01:16:55 +0000 (18:16 -0700)]
[PATCH] memory hotplug: move section_mem_map alloc to sparse.c

This basically keeps up from having to extern __kmalloc_section_memmap().

The vaddr_in_vmalloc_area() helper could go in a vmalloc header, but that
header gets hard to work with, because it needs some arch-specific macros.
Just stick it in here for now, instead of creating another header.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Lion Vollnhals <webmaster@schiggl.de>
Signed-off-by: Jiri Slaby <xslaby@fi.muni.cz>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug: sysfs and add/remove functions
Dave Hansen [Sun, 30 Oct 2005 01:16:54 +0000 (18:16 -0700)]
[PATCH] memory hotplug: sysfs and add/remove functions

This adds generic memory add/remove and supporting functions for memory
hotplug into a new file as well as a memory hotplug kernel config option.

Individual architecture patches will follow.

For now, disable memory hotplug when swsusp is enabled.  There's a lot of
churn there right now.  We'll fix it up properly once it calms down.

Signed-off-by: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug locking: zone span seqlock
Dave Hansen [Sun, 30 Oct 2005 01:16:53 +0000 (18:16 -0700)]
[PATCH] memory hotplug locking: zone span seqlock

See the "fixup bad_range()" patch for more information, but this actually
creates a the lock to protect things making assumptions about a zone's size
staying constant at runtime.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug locking: node_size_lock
Dave Hansen [Sun, 30 Oct 2005 01:16:52 +0000 (18:16 -0700)]
[PATCH] memory hotplug locking: node_size_lock

pgdat->node_size_lock is basically only neeeded in one place in the normal
code: show_mem(), which is the arch-specific sysrq-m printing function.

Strictly speaking, the architectures not doing memory hotplug do no need this
locking in show_mem().  However, they are all included for completeness.  This
should also make any future consolidation of all of the implementations a
little more straightforward.

This lock is also held in the sparsemem code during a memory removal, as
sections are invalidated.  This is the place there pfn_valid() is made false
for a memory area that's being removed.  The lock is only required when doing
pfn_valid() operations on memory which the user does not already have a
reference on the page, such as in show_mem().

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug prep: fixup bad_range()
Dave Hansen [Sun, 30 Oct 2005 01:16:52 +0000 (18:16 -0700)]
[PATCH] memory hotplug prep: fixup bad_range()

When doing memory hotplug operations, the size of existing zones can obviously
change.  This means that zone->zone_{start_pfn,spanned_pages} can change.

There are currently no locks that protect these structure members.  However,
they are rarely accessed at runtime.  Outside of swsusp, the only place that I
can find is bad_range().

So, split bad_range() up into two pieces: one that needs to be locked and
anther that doesn't.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug prep: __section_nr helper
Dave Hansen [Sun, 30 Oct 2005 01:16:51 +0000 (18:16 -0700)]
[PATCH] memory hotplug prep: __section_nr helper

A little helper that we use in the hotplug code.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug prep: break out zone initialization
Dave Hansen [Sun, 30 Oct 2005 01:16:50 +0000 (18:16 -0700)]
[PATCH] memory hotplug prep: break out zone initialization

If a zone is empty at boot-time and then hot-added to later, it needs to run
the same init code that would have been run on it at boot.

This patch breaks out zone table and per-cpu-pages functions for use by the
hotplug code.  You can almost see all of the free_area_init_core() function on
one page now.  :)

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] memory hotplug prep: kill local_mapnr
Dave Hansen [Sun, 30 Oct 2005 01:16:49 +0000 (18:16 -0700)]
[PATCH] memory hotplug prep: kill local_mapnr

The following series implements memory hot-add for ppc64 and i386.  There are
x86_64 and ia64 implementations that will be submitted shortly as well,
through the normal maintainers.

This patch:

local_mapnr is unused, except for in an alpha header.  Keep the alpha one,
kill the rest.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] .text page fault SMP scalability optimization
Andrea Arcangeli [Sun, 30 Oct 2005 01:16:48 +0000 (18:16 -0700)]
[PATCH] .text page fault SMP scalability optimization

We had a problem on ppc64 where with more than 4 threads a large system
wouldn't scale well while faulting in the .text (most of the time was spent
in the kernel despite it was an userland compute intensive app).  The
reason is the useless overwrite of the same pte from all cpu.

I fixed it this way (verified on an older kernel but the forward port is
almost identical).  This will benefit all archs not just ppc64.

Signed-off-by: Andrea Arcangeli <andrea@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] hugetlb: overcommit accounting check
Adam Litke [Sun, 30 Oct 2005 01:16:47 +0000 (18:16 -0700)]
[PATCH] hugetlb: overcommit accounting check

Basic overcommit checking for hugetlb_file_map() based on an implementation
used with demand faulting in SLES9.

Since demand faulting can't guarantee the availability of pages at mmap
time, this patch implements a basic sanity check to ensure that the number
of huge pages required to satisfy the mmap are currently available.
Despite the obvious race, I think it is a good start on doing proper
accounting.  I'd like to work towards an accounting system that mimics the
semantics of normal pages (especially for the MAP_PRIVATE/COW case).  That
work is underway and builds on what this patch starts.

Huge page shared memory segments are simpler and still maintain their
commit on shmget semantics.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] hugetlb: demand fault handler
Adam Litke [Sun, 30 Oct 2005 01:16:46 +0000 (18:16 -0700)]
[PATCH] hugetlb: demand fault handler

Below is a patch to implement demand faulting for huge pages.  The main
motivation for changing from prefaulting to demand faulting is so that huge
page memory areas can be allocated according to NUMA policy.

Thanks to consolidated hugetlb code, switching the behavior requires changing
only one fault handler.  The bulk of the patch just moves the logic from
hugelb_prefault() to hugetlb_pte_fault() and find_get_huge_page().

Signed-off-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] hugetlb: remove repeated code
Krishnakumar R [Sun, 30 Oct 2005 01:16:45 +0000 (18:16 -0700)]
[PATCH] hugetlb: remove repeated code

Clean up some repeated code related to HugeTLB.  hugetlb_zero_setup would
have already allocated the file->f_op.

Signed-off-by: Krishnakumar. R <rkrishnakumar@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] cleanup hugelbfs_forget_inode
Christoph Hellwig [Sun, 30 Oct 2005 01:16:45 +0000 (18:16 -0700)]
[PATCH] cleanup hugelbfs_forget_inode

Reformat hugelbfs_forget_inode and add the missing but harmless
write_inode_now call.  It looks the same as generic_forget_inode now except
for the call to truncate_hugepages instead of truncate_inode_pages.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] kill hugelbfs_do_delete_inode
Christoph Hellwig [Sun, 30 Oct 2005 01:16:44 +0000 (18:16 -0700)]
[PATCH] kill hugelbfs_do_delete_inode

hugetlbfs_do_delete_inode is the same as generic_delete_inode now, so remove
it in favour of the latter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] hugetlbfs: clean up hugetlbfs_delete_inode
Christoph Hellwig [Sun, 30 Oct 2005 01:16:43 +0000 (18:16 -0700)]
[PATCH] hugetlbfs: clean up hugetlbfs_delete_inode

Make hugetlbfs looks the same as generic_detelte_inode, fixing a bunch of
missing updates to it at the same time.  Rename it to
hugetlbfs_do_delete_inode and add a real hugetlbfs_delete_inode that
implements ->delete_inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] hugetlbfs: move free_inodes accounting
Christoph Hellwig [Sun, 30 Oct 2005 01:16:42 +0000 (18:16 -0700)]
[PATCH] hugetlbfs: move free_inodes accounting

Move hugetlbfs accounting into ->alloc_inode / ->destroy_inode.  This keeps
the code simpler, fixes a loeak where a failing inode allocation wouldn't
decrement the counter and moves hugetlbfs_delete_inode and
hugetlbfs_forget_inode closer to their generic counterparts.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: update comments to pte lock
Hugh Dickins [Sun, 30 Oct 2005 01:16:41 +0000 (18:16 -0700)]
[PATCH] mm: update comments to pte lock

Updated several references to page_table_lock in common code comments.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: fix rss and mmlist locking
Hugh Dickins [Sun, 30 Oct 2005 01:16:41 +0000 (18:16 -0700)]
[PATCH] mm: fix rss and mmlist locking

A couple of oddities were guarded by page_table_lock, no longer properly
guarded when that is split.

The mm_counters of file_rss and anon_rss: make those an atomic_t, or an
atomic64_t if the architecture supports it, in such a case.  Definitions by
courtesy of Christoph Lameter: who spent considerable effort on more scalable
ways of counting, but found insufficient benefit in practice.

And adding an mm with swap to the mmlist for swapoff: the list is well-
guarded by its own lock, but the list_empty check now has to be repeated
inside it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: split page table lock
Hugh Dickins [Sun, 30 Oct 2005 01:16:40 +0000 (18:16 -0700)]
[PATCH] mm: split page table lock

Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
a many-threaded application which concurrently initializes different parts of
a large anonymous area.

This patch corrects that, by using a separate spinlock per page table page, to
guard the page table entries in that page, instead of using the mm's single
page_table_lock.  (But even then, page_table_lock is still used to guard page
table allocation, and anon_vma allocation.)

In this implementation, the spinlock is tucked inside the struct page of the
page table page: with a BUILD_BUG_ON in case it overflows - which it would in
the case of 32-bit PA-RISC with spinlock debugging enabled.

Splitting the lock is not quite for free: another cacheline access.  Ideally,
I suppose we would use split ptlock only for multi-threaded processes on
multi-cpu machines; but deciding that dynamically would have its own costs.
So for now enable it by config, at some number of cpus - since the Kconfig
language doesn't support inequalities, let preprocessor compare that with
NR_CPUS.  But I don't think it's worth being user-configurable: for good
testing of both split and unsplit configs, split now at 4 cpus, and perhaps
change that to 8 later.

There is a benefit even for singly threaded processes: kswapd can be attacking
one part of the mm while another part is busy faulting.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: uml kill unused
Hugh Dickins [Sun, 30 Oct 2005 01:16:39 +0000 (18:16 -0700)]
[PATCH] mm: uml kill unused

In worrying over the various pte operations in different architectures, I came
across some unused functions in UML: remove mprotect_kernel_vm,
protect_vm_page and addr_pte.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: uml pte atomicity
Hugh Dickins [Sun, 30 Oct 2005 01:16:38 +0000 (18:16 -0700)]
[PATCH] mm: uml pte atomicity

There's usually a good reason when a pte is examined without the lock; but it
makes me nervous when the pointer is dereferenced more than once.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: cris v32 mmu_context_lock
Hugh Dickins [Sun, 30 Oct 2005 01:16:37 +0000 (18:16 -0700)]
[PATCH] mm: cris v32 mmu_context_lock

The cris v32 switch_mm guards get_mmu_context with next->page_table_lock: good
it's not really SMP yet, since get_mmu_context messes with global variables
affecting other mms.  Replace by global mmu_context_lock.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: parisc pte atomicity
Hugh Dickins [Sun, 30 Oct 2005 01:16:36 +0000 (18:16 -0700)]
[PATCH] mm: parisc pte atomicity

There's a worrying function translation_exists in parisc cacheflush.h,
unaffected by split ptlock since flush_dcache_page is using it on some other
mm, without any relevant lock.  Oh well, make it a slightly more robust by
factoring the pfn check within it.  And it looked liable to confuse a
camouflaged swap or file entry with a good pte: fix that too.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: arm ready for split ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:36 +0000 (18:16 -0700)]
[PATCH] mm: arm ready for split ptlock

Prepare arm for the split page_table_lock: three issues.

Signal handling's preserve and restore of iwmmxt context currently involves
reading and writing that context to and from user space, while holding
page_table_lock to secure the user page(s) against kswapd.  If we split the
lock, then the structure might span two pages, secured by to read into and
write from a kernel stack buffer, copying that out and in without locking (the
structure is 160 bytes in size, and here we're near the top of the kernel
stack).  Or would the overhead be noticeable?

arm_syscall's cmpxchg emulation use pte_offset_map_lock, instead of
pte_offset_map and mm-wide page_table_lock; and strictly, it should now also
take mmap_sem before descending to pmd, to guard against another thread
munmapping, and the page table pulled out beneath this thread.

Updated two comments in fault-armv.c.  adjust_pte is interesting, since its
modification of a pte in one part of the mm depends on the lock held when
calling update_mmu_cache for a pte in some other part of that mm.  This can't
be done with a split page_table_lock (and we've already taken the lowest lock
in the hierarchy here): so we'll have to disable split on arm, unless
CONFIG_CPU_CACHE_VIPT to ensures adjust_pte never used.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: i386 sh sh64 ready for split ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:34 +0000 (18:16 -0700)]
[PATCH] mm: i386 sh sh64 ready for split ptlock

Use pte_offset_map_lock, instead of pte_offset_map (or inappropriate
pte_offset_kernel) and mm-wide page_table_lock, in sundry arch places.

The i386 vm86 mark_screen_rdonly: yes, there was and is an assumption that the
screen fits inside the one page table, as indeed it does.

The sh __do_page_fault: which handles both kernel faults (without lock) and
user mm faults (locked - though it set_pte without locking before).

The sh64 flush_cache_range and helpers: which wrongly thought callers held
page_table_lock before (only its tlb_start_vma did, and no longer does so);
moved the flush loop down, and adjusted the large versus small range decision
to consider a range which spans page tables as large.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: follow_page with inner ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:33 +0000 (18:16 -0700)]
[PATCH] mm: follow_page with inner ptlock

Final step in pushing down common core's page_table_lock.  follow_page no
longer wants caller to hold page_table_lock, uses pte_offset_map_lock itself;
and so no page_table_lock is taken in get_user_pages itself.

But get_user_pages (and get_futex_key) do then need follow_page to pin the
page for them: take Daniel's suggestion of bitflags to follow_page.

Need one for WRITE, another for TOUCH (it was the accessed flag before:
vanished along with check_user_page_readable, but surely get_numa_maps is
wrong to mark every page it finds as accessed), another for GET.

And another, ANON to dispose of untouched_anonymous_page: it seems silly for
that to descend a second time, let follow_page observe if there was no page
table and return ZERO_PAGE if so.  Fix minor bug in that: check VM_LOCKED -
make_pages_present ought to make readonly anonymous present.

Give get_numa_maps a cond_resched while we're there.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: kill check_user_page_readable
Hugh Dickins [Sun, 30 Oct 2005 01:16:32 +0000 (18:16 -0700)]
[PATCH] mm: kill check_user_page_readable

check_user_page_readable is a problematic variant of follow_page.  It's used
only by oprofile's i386 and arm backtrace code, at interrupt time, to
establish whether a userspace stackframe is currently readable.

This is problematic, because we want to push the page_table_lock down inside
follow_page, and later split it; whereas oprofile is doing a spin_trylock on
it (in the i386 case, forgotten in the arm case), and needs that to pin
perhaps two pages spanned by the stackframe (which might be covered by
different locks when we split).

I think oprofile is going about this in the wrong way: it doesn't need to know
the area is readable (neither i386 nor arm uses read protection of user
pages), it doesn't need to pin the memory, it should simply
__copy_from_user_inatomic, and see if that succeeds or not.  Sorry, but I've
not got around to devising the sparse __user annotations for this.

Then we can eliminate check_user_page_readable, and return to a single
follow_page without the __follow_page variants.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: rmap with inner ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:31 +0000 (18:16 -0700)]
[PATCH] mm: rmap with inner ptlock

rmap's page_check_address descend without page_table_lock.  First just
pte_offset_map in case there's no pte present worth locking for, then take
page_table_lock for the full check, and pass ptl back to caller in the same
style as pte_offset_map_lock.  __xip_unmap, page_referenced_one and
try_to_unmap_one use pte_unmap_unlock.  try_to_unmap_cluster also.

page_check_address reformatted to avoid progressive indentation.  No use is
made of its one error code, return NULL when it fails.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: xip_unmap ZERO_PAGE fix
Hugh Dickins [Sun, 30 Oct 2005 01:16:31 +0000 (18:16 -0700)]
[PATCH] mm: xip_unmap ZERO_PAGE fix

Small fix to the PageReserved patch: the mips ZERO_PAGE(address) depends on
address, so __xip_unmap is wrong to initialize page with that before address
is initialized; and in fact must re-evaluate it each iteration.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: unmap_vmas with inner ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:30 +0000 (18:16 -0700)]
[PATCH] mm: unmap_vmas with inner ptlock

Remove the page_table_lock from around the calls to unmap_vmas, and replace
the pte_offset_map in zap_pte_range by pte_offset_map_lock: all callers are
now safe to descend without page_table_lock.

Don't attempt fancy locking for hugepages, just take page_table_lock in
unmap_hugepage_range.  Which makes zap_hugepage_range, and the hugetlb test in
zap_page_range, redundant: unmap_vmas calls unmap_hugepage_range anyway.  Nor
does unmap_vmas have much use for its mm arg now.

The tlb_start_vma and tlb_end_vma in unmap_page_range are now called without
page_table_lock: if they're implemented at all, they typically come down to
flush_cache_range (usually done outside page_table_lock) and flush_tlb_range
(which we already audited for the mprotect case).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: unlink vma before pagetables
Hugh Dickins [Sun, 30 Oct 2005 01:16:29 +0000 (18:16 -0700)]
[PATCH] mm: unlink vma before pagetables

In most places the descent from pgd to pud to pmd to pte holds mmap_sem
(exclusively or not), which ensures that free_pgtables cannot be freeing page
tables from any level at the same time.  But truncation and reverse mapping
descend without mmap_sem.

No problem: just make sure that a vma is unlinked from its prio_tree (or
nonlinear list) and from its anon_vma list, after zapping the vma, but before
freeing its page tables.  Then neither vmtruncate nor rmap can reach that vma
whose page tables are now volatile (nor do they need to reach it, since all
its page entries have been zapped by this stage).

The i_mmap_lock and anon_vma->lock already serialize this correctly; but the
locking hierarchy is such that we cannot take them while holding
page_table_lock.  Well, we're trying to push that down anyway.  So in this
patch, move anon_vma_unlink and unlink_file_vma into free_pgtables, at the
same time as moving page_table_lock around calls to unmap_vmas.

tlb_gather_mmu and tlb_finish_mmu then fall outside the page_table_lock, but
we made them preempt_disable and preempt_enable earlier; and a long source
audit of all the architectures has shown no problem with removing
page_table_lock from them.  free_pgtables doesn't need page_table_lock for
itself, nor for what it calls; tlb->mm->nr_ptes is usually protected by
page_table_lock, but partly by non-exclusive mmap_sem - here it's decremented
with exclusive mmap_sem, or mm_users 0.  update_hiwater_rss and
vm_unacct_memory don't need page_table_lock either.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: flush_tlb_range outside ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:28 +0000 (18:16 -0700)]
[PATCH] mm: flush_tlb_range outside ptlock

There was one small but very significant change in the previous patch:
mprotect's flush_tlb_range fell outside the page_table_lock: as it is in 2.4,
but that doesn't prove it safe in 2.6.

On some architectures flush_tlb_range comes to the same as flush_tlb_mm, which
has always been called from outside page_table_lock in dup_mmap, and is so
proved safe.  Others required a deeper audit: I could find no reliance on
page_table_lock in any; but in ia64 and parisc found some code which looks a
bit as if it might want preemption disabled.  That won't do any actual harm,
so pending a decision from the maintainers, disable preemption there.

Remove comments on page_table_lock from flush_tlb_mm, flush_tlb_range and
flush_tlb_page entries in cachetlb.txt: they were rather misleading (what
generic code does is different from what usually happens), the rules are now
changing, and it's not yet clear where we'll end up (will the generic
tlb_flush_mmu happen always under lock?  never under lock?  or sometimes under
and sometimes not?).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: pte_offset_map_lock loops
Hugh Dickins [Sun, 30 Oct 2005 01:16:27 +0000 (18:16 -0700)]
[PATCH] mm: pte_offset_map_lock loops

Convert those common loops using page_table_lock on the outside and
pte_offset_map within to use just pte_offset_map_lock within instead.

These all hold mmap_sem (some exclusively, some not), so at no level can a
page table be whipped away from beneath them.  But whereas pte_alloc loops
tested with the "atomic" pmd_present, these loops are testing with pmd_none,
which on i386 PAE tests both lower and upper halves.

That's now unsafe, so add a cast into pmd_none to test only the vital lower
half: we lose a little sensitivity to a corrupt middle directory, but not
enough to worry about.  It appears that i386 and UML were the only
architectures vulnerable in this way, and pgd and pud no problem.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: page fault handler locking
Hugh Dickins [Sun, 30 Oct 2005 01:16:26 +0000 (18:16 -0700)]
[PATCH] mm: page fault handler locking

On the page fault path, the patch before last pushed acquiring the
page_table_lock down to the head of handle_pte_fault (though it's also taken
and dropped earlier when a new page table has to be allocated).

Now delete that line, read "entry = *pte" without it, and go off to this or
that page fault handler on the basis of this unlocked peek.  Usually the
handler can proceed without the lock, relying on the subsequent locked
pte_same or pte_none test to back out when necessary; though do_wp_page needs
the lock immediately, and do_file_page doesn't check (if there's a race,
install_page just zaps the entry and reinstalls it).

But on those architectures (notably i386 with PAE) whose pte is too big to be
read atomically, if SMP or preemption is enabled, do_swap_page and
do_file_page might cause irretrievable damage if passed a Frankenstein entry
stitched together from unrelated parts.  In those configs, "pte_unmap_same"
has to take page_table_lock, validate orig_pte still the same, and drop
page_table_lock before unmapping, before proceeding.

Use pte_offset_map_lock and pte_unmap_unlock throughout the handlers; but lock
avoidance leaves more lone maps and unmaps than elsewhere.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: arches skip ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:24 +0000 (18:16 -0700)]
[PATCH] mm: arches skip ptlock

Convert those few architectures which are calling pud_alloc, pmd_alloc,
pte_alloc_map on a user mm, not to take the page_table_lock first, nor drop it
after.  Each of these can continue to use pte_alloc_map, no need to change
over to pte_alloc_map_lock, they're neither racy nor swappable.

In the sparc64 io_remap_pfn_range, flush_tlb_range then falls outside of the
page_table_lock: that's okay, on sparc64 it's like flush_tlb_mm, and that has
always been called from outside of page_table_lock in dup_mmap.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: ptd_alloc take ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:23 +0000 (18:16 -0700)]
[PATCH] mm: ptd_alloc take ptlock

Second step in pushing down the page_table_lock.  Remove the temporary
bridging hack from __pud_alloc, __pmd_alloc, __pte_alloc: expect callers not
to hold page_table_lock, whether it's on init_mm or a user mm; take
page_table_lock internally to check if a racing task already allocated.

Convert their callers from common code.  But avoid coming back to change them
again later: instead of moving the spin_lock(&mm->page_table_lock) down,
switch over to new macros pte_alloc_map_lock and pte_unmap_unlock, which
encapsulate the mapping+locking and unlocking+unmapping together, and in the
end may use alternatives to the mm page_table_lock itself.

These callers all hold mmap_sem (some exclusively, some not), so at no level
can a page table be whipped away from beneath them; and pte_alloc uses the
"atomic" pmd_present to test whether it needs to allocate.  It appears that on
all arches we can safely descend without page_table_lock.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: ptd_alloc inline and out
Hugh Dickins [Sun, 30 Oct 2005 01:16:22 +0000 (18:16 -0700)]
[PATCH] mm: ptd_alloc inline and out

It seems odd to me that, whereas pud_alloc and pmd_alloc test inline, only
calling out-of-line __pud_alloc __pmd_alloc if allocation needed,
pte_alloc_map and pte_alloc_kernel are entirely out-of-line.  Though it does
add a little to kernel size, change them to macros testing inline, calling
__pte_alloc or __pte_alloc_kernel to allocate out-of-line.  Mark none of them
as fastcalls, leave that to CONFIG_REGPARM or not.

It also seems more natural for the out-of-line functions to leave the offset
calculation and map to the inline, which has to do it anyway for the common
case.  At least mremap move wants __pte_alloc without _map.

Macros rather than inline functions, certainly to avoid the header file issues
which arise from CONFIG_HIGHPTE needing kmap_types.h, but also in case any
architectures I haven't built would have other such problems.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: init_mm without ptlock
Hugh Dickins [Sun, 30 Oct 2005 01:16:21 +0000 (18:16 -0700)]
[PATCH] mm: init_mm without ptlock

First step in pushing down the page_table_lock.  init_mm.page_table_lock has
been used throughout the architectures (usually for ioremap): not to serialize
kernel address space allocation (that's usually vmlist_lock), but because
pud_alloc,pmd_alloc,pte_alloc_kernel expect caller holds it.

Reverse that: don't lock or unlock init_mm.page_table_lock in any of the
architectures; instead rely on pud_alloc,pmd_alloc,pte_alloc_kernel to take
and drop it when allocating a new one, to check lest a racing task already
did.  Similarly no page_table_lock in vmalloc's map_vm_area.

Some temporary ugliness in __pud_alloc and __pmd_alloc: since they also handle
user mms, which are converted only by a later patch, for now they have to lock
differently according to whether or not it's init_mm.

If sources get muddled, there's a danger that an arch source taking
init_mm.page_table_lock will be mixed with common source also taking it (or
neither take it).  So break the rules and make another change, which should
break the build for such a mismatch: remove the redundant mm arg from
pte_alloc_kernel (ppc64 scrapped its distinct ioremap_mm in 2.6.13).

Exceptions: arm26 used pte_alloc_kernel on user mm, now pte_alloc_map; ia64
used pte_alloc_map on init_mm, now pte_alloc_kernel; parisc had bad args to
pmd_alloc and pte_alloc_kernel in unused USE_HPPA_IOREMAP code; ppc64
map_io_page forgot to unlock on failure; ppc mmu_mapin_ram and ppc64 im_free
took page_table_lock for no good reason.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: ia64 use expand_upwards
Hugh Dickins [Sun, 30 Oct 2005 01:16:20 +0000 (18:16 -0700)]
[PATCH] mm: ia64 use expand_upwards

ia64 has expand_backing_store function for growing its Register Backing Store
vma upwards.  But more complete code for this purpose is found in the
CONFIG_STACK_GROWSUP part of mm/mmap.c.  Uglify its #ifdefs further to provide
expand_upwards for ia64 as well as expand_stack for parisc.

The Register Backing Store vma should be marked VM_ACCOUNT.  Implement the
intention of growing it only a page at a time, instead of passing an address
outside of the vma to handle_mm_fault, with unknown consequences.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: mm_struct hiwaters moved
Hugh Dickins [Sun, 30 Oct 2005 01:16:19 +0000 (18:16 -0700)]
[PATCH] mm: mm_struct hiwaters moved

Slight and timid rearrangement of mm_struct: hiwater_rss and hiwater_vm were
tacked on the end, but it seems better to keep them near _file_rss, _anon_rss
and total_vm, in the same cacheline on those arches verified.

There are likely to be more profitable rearrangements, but less obvious (is it
good or bad that saved_auxv[AT_VECTOR_SIZE] isolates cpu_vm_mask and context
from many others?), needing serious instrumentation.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: update_hiwaters just in time
Hugh Dickins [Sun, 30 Oct 2005 01:16:18 +0000 (18:16 -0700)]
[PATCH] mm: update_hiwaters just in time

update_mem_hiwater has attracted various criticisms, in particular from those
concerned with mm scalability.  Originally it was called whenever rss or
total_vm got raised.  Then many of those callsites were replaced by a timer
tick call from account_system_time.  Now Frank van Maarseveen reports that to
be found inadequate.  How about this?  Works for Frank.

Replace update_mem_hiwater, a poor combination of two unrelated ops, by macros
update_hiwater_rss and update_hiwater_vm.  Don't attempt to keep
mm->hiwater_rss up to date at timer tick, nor every time we raise rss (usually
by 1): those are hot paths.  Do the opposite, update only when about to lower
rss (usually by many), or just before final accounting in do_exit.  Handle
mm->hiwater_vm in the same way, though it's much less of an issue.  Demand
that whoever collects these hiwater statistics do the work of taking the
maximum with rss or total_vm.

And there has been no collector of these hiwater statistics in the tree.  The
new convention needs an example, so match Frank's usage by adding a VmPeak
line above VmSize to /proc/<pid>/status, and also a VmHWM line above VmRSS
(High-Water-Mark or High-Water-Memory).

There was a particular anomaly during mremap move, that hiwater_vm might be
captured too high.  A fleeting such anomaly remains, but it's quickly
corrected now, whereas before it would stick.

What locking?  None: if the app is racy then these statistics will be racy,
it's not worth any overhead to make them exact.  But whenever it suits,
hiwater_vm is updated under exclusive mmap_sem, and hiwater_rss under
page_table_lock (for now) or with preemption disabled (later on): without
going to any trouble, minimize the time between reading current values and
updating, to minimize those occasions when a racing thread bumps a count up
and back down in between.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: zap_pte out of line
Hugh Dickins [Sun, 30 Oct 2005 01:16:17 +0000 (18:16 -0700)]
[PATCH] mm: zap_pte out of line

There used to be just one call to zap_pte, but it shouldn't be inline now
there are two.  Check for the common case pte_none before calling, and move
its rss accounting up into install_page or install_file_pte - which helps the
next patch.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: do_mremap current mm
Hugh Dickins [Sun, 30 Oct 2005 01:16:16 +0000 (18:16 -0700)]
[PATCH] mm: do_mremap current mm

Cleanup: relieve do_mremap from its surfeit of current->mms.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: do_swap_page race major
Hugh Dickins [Sun, 30 Oct 2005 01:16:15 +0000 (18:16 -0700)]
[PATCH] mm: do_swap_page race major

Small adjustment: do_swap_page should report its !pte_same race as a major
fault if it had to read into swap cache, because whatever raced with it will
have found page already in cache and reported minor fault.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: zap_pte_range dec rss
Hugh Dickins [Sun, 30 Oct 2005 01:16:14 +0000 (18:16 -0700)]
[PATCH] mm: zap_pte_range dec rss

Small adjustment: zap_pte_range decrement its rss counts from 0 then finally
add, avoiding negations - we don't have or need a sub_mm_rss.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: copy_one_pte inc rss
Hugh Dickins [Sun, 30 Oct 2005 01:16:13 +0000 (18:16 -0700)]
[PATCH] mm: copy_one_pte inc rss

Small adjustment, following Nick's suggestion: it's more straightforward for
copy_pte_range to let copy_one_pte do the rss incrementation, than use an
index it passed back.  Saves a #define, and 16 bytes of .text.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] core remove PageReserved
Nick Piggin [Sun, 30 Oct 2005 01:16:12 +0000 (18:16 -0700)]
[PATCH] core remove PageReserved

Remove PageReserved() calls from core code by tightening VM_RESERVED
handling in mm/ to cover PageReserved functionality.

PageReserved special casing is removed from get_page and put_page.

All setting and clearing of PageReserved is retained, and it is now flagged
in the page_alloc checks to help ensure we don't introduce any refcount
based freeing of Reserved pages.

MAP_PRIVATE, PROT_WRITE of VM_RESERVED regions is tentatively being
deprecated.  We never completely handled it correctly anyway, and is be
reintroduced in future if required (Hugh has a proof of concept).

Once PageReserved() calls are removed from kernel/power/swsusp.c, and all
arch/ and driver code, the Set and Clear calls, and the PG_reserved bit can
be trivially removed.

Last real user of PageReserved is swsusp, which uses PageReserved to
determine whether a struct page points to valid memory or not.  This still
needs to be addressed (a generic page_is_ram() should work).

A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and
thus mapcounted and count towards shared rss).  These writes to the struct
page could cause excessive cacheline bouncing on big systems.  There are a
number of ways this could be addressed if it is an issue.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Refcount bug fix for filemap_xip.c

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: m68k kill stram swap
Hugh Dickins [Sun, 30 Oct 2005 01:16:10 +0000 (18:16 -0700)]
[PATCH] mm: m68k kill stram swap

Please, please now delete the Atari CONFIG_STRAM_SWAP code.  It may be
excellent and ingenious code, but its reference to swap_vfsmnt betrays that it
hasn't been built since 2.5.1 (four years old come December), it's delving
deep into matters which are the preserve of core mm code, its only purpose is
to give the more conscientious mm guys an anxiety attack from time to time;
yet we keep on breaking it more and more.

If you want to use RAM for swap, then if the MTD driver does not already
provide just what you need, I'm sure David could be persuaded to add the
extra.  But you'd also like to be able to allocate extents of that swap for
other use: we can give you a core interface for that if you need.  But unbuilt
for four years suggests to me that there's no need at all.

I cannot swear the patch below won't break your build, but believe so.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: sh64 hugetlbpage.c
Hugh Dickins [Sun, 30 Oct 2005 01:16:09 +0000 (18:16 -0700)]
[PATCH] mm: sh64 hugetlbpage.c

The sh64 hugetlbpage.c seems to be erroneous, left over from a bygone age,
clashing with the common hugetlb.c.  Replace it by a copy of the sh
hugetlbpage.c.  Except, delete that mk_pte_huge macro neither uses.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: dup_mmap down new mmap_sem
Hugh Dickins [Sun, 30 Oct 2005 01:16:08 +0000 (18:16 -0700)]
[PATCH] mm: dup_mmap down new mmap_sem

One anomaly remains from when Andrea rationalized the responsibilities of
mmap_sem and page_table_lock: in dup_mmap we add vmas to the child holding its
page_table_lock, but not the mmap_sem which normally guards the vma list and
rbtree.  Which could be an issue for unuse_mm: though since it just walks down
the list (today with page_table_lock, tomorrow not), it's probably okay.  Will
need a memory barrier?  Oh, keep it simple, Nick and I agreed, no harm in
taking child's mmap_sem here.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: dup_mmap use oldmm more
Hugh Dickins [Sun, 30 Oct 2005 01:16:06 +0000 (18:16 -0700)]
[PATCH] mm: dup_mmap use oldmm more

Use the parent's oldmm throughout dup_mmap, instead of perversely going back
to current->mm.  (Can you hear the sigh of relief from those mpnts?  Usually I
squash them, but not today.)

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: batch updating mm_counters
Hugh Dickins [Sun, 30 Oct 2005 01:16:05 +0000 (18:16 -0700)]
[PATCH] mm: batch updating mm_counters

tlb_finish_mmu used to batch zap_pte_range's update of mm rss, which may be
worthwhile if the mm is contended, and would reduce atomic operations if the
counts were atomic.  Let zap_pte_range now batch its updates to file_rss and
anon_rss, per page-table in case we drop the lock outside; and copy_pte_range
batch them too.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: rss = file_rss + anon_rss
Hugh Dickins [Sun, 30 Oct 2005 01:16:05 +0000 (18:16 -0700)]
[PATCH] mm: rss = file_rss + anon_rss

I was lazy when we added anon_rss, and chose to change as few places as
possible.  So currently each anonymous page has to be counted twice, in rss
and in anon_rss.  Which won't be so good if those are atomic counts in some
configurations.

Change that around: keep file_rss and anon_rss separately, and add them
together (with get_mm_rss macro) when the total is needed - reading two
atomics is much cheaper than updating two atomics.  And update anon_rss
upfront, typically in memory.c, not tucked away in page_add_anon_rmap.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: mm_init set_mm_counters
Hugh Dickins [Sun, 30 Oct 2005 01:16:04 +0000 (18:16 -0700)]
[PATCH] mm: mm_init set_mm_counters

How is anon_rss initialized?  In dup_mmap, and by mm_alloc's memset; but
that's not so good if an mm_counter_t is a special type.  And how is rss
initialized?  By set_mm_counter, all over the place.  Come on, we just need to
initialize them both at once by set_mm_counter in mm_init (which follows the
memcpy when forking).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: tlb_finish_mmu forget rss
Hugh Dickins [Sun, 30 Oct 2005 01:16:03 +0000 (18:16 -0700)]
[PATCH] mm: tlb_finish_mmu forget rss

zap_pte_range has been counting the pages it frees in tlb->freed, then
tlb_finish_mmu has used that to update the mm's rss.  That got stranger when I
added anon_rss, yet updated it by a different route; and stranger when rss and
anon_rss became mm_counters with special access macros.  And it would no
longer be viable if we're relying on page_table_lock to stabilize the
mm_counter, but calling tlb_finish_mmu outside that lock.

Remove the mmu_gather's freed field, let tlb_finish_mmu stick to its own
business, just decrement the rss mm_counter in zap_pte_range (yes, there was
some point to batching the update, and a subsequent patch restores that).  And
forget the anal paranoia of first reading the counter to avoid going negative
- if rss does go negative, just fix that bug.

Remove the mmu_gather's flushes and avoided_flushes from arm and arm26: no use
was being made of them.  But arm26 alone was actually using the freed, in the
way some others use need_flush: give it a need_flush.  arm26 seems to prefer
spaces to tabs here: respect that.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: tlb_is_full_mm was obscure
Hugh Dickins [Sun, 30 Oct 2005 01:16:02 +0000 (18:16 -0700)]
[PATCH] mm: tlb_is_full_mm was obscure

tlb_is_full_mm?  What does that mean?  The TLB is full?  No, it means that the
mm's last user has gone and the whole mm is being torn down.  And it's an
inline function because sparc64 uses a different (slightly better)
"tlb_frozen" name for the flag others call "fullmm".

And now the ptep_get_and_clear_full macro used in zap_pte_range refers
directly to tlb->fullmm, which would be wrong for sparc64.  Rather than
correct that, I'd prefer to scrap tlb_is_full_mm altogether, and change
sparc64 to just use the same poor name as everyone else - is that okay?

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: tlb_gather_mmu get_cpu_var
Hugh Dickins [Sun, 30 Oct 2005 01:16:01 +0000 (18:16 -0700)]
[PATCH] mm: tlb_gather_mmu get_cpu_var

tlb_gather_mmu dates from before kernel preemption was allowed, and uses
smp_processor_id or __get_cpu_var to find its per-cpu mmu_gather.  That works
because it's currently only called after getting page_table_lock, which is not
dropped until after the matching tlb_finish_mmu.  But don't rely on that, it
will soon change: now disable preemption internally by proper get_cpu_var in
tlb_gather_mmu, put_cpu_var in tlb_finish_mmu.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: move_page_tables by extents
Hugh Dickins [Sun, 30 Oct 2005 01:16:00 +0000 (18:16 -0700)]
[PATCH] mm: move_page_tables by extents

Speeding up mremap's moving of ptes has never been a priority, but the locking
will get more complicated shortly, and is already too baroque.

Scrap the current one-by-one moving, do an extent at a time: curtailed by end
of src and dst pmds (have to use PMD_SIZE: the way pmd_addr_end gets elided
doesn't match this usage), and by latency considerations.

One nice property of the old method is lost: it never allocated a page table
unless absolutely necessary, so you could free empty page tables by mremapping
to and fro.  Whereas this way, it allocates a dst table wherever there was a
src table.  I keep diving in to reinstate the old behaviour, then come out
preferring not to clutter how it now is.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: page fault handlers tidyup
Hugh Dickins [Sun, 30 Oct 2005 01:15:59 +0000 (18:15 -0700)]
[PATCH] mm: page fault handlers tidyup

Impose a little more consistency on the page fault handlers do_wp_page,
do_swap_page, do_anonymous_page, do_no_page, do_file_page: why not pass their
arguments in the same order, called the same names?

break_cow is all very well, but what it did was inlined elsewhere: easier to
compare if it's brought back into do_wp_page.

do_file_page's fallback to do_no_page dates from a time when we were testing
pte_file by using it wherever possible: currently it's peculiar to nonlinear
vmas, so just check that.  BUG_ON if not?  Better not, it's probably page
table corruption, so just show the pte: hmm, there's a pte_ERROR macro, let's
use that for do_wp_page's invalid pfn too.

Hah!  Someone in the ppc64 world noticed pte_ERROR was unused so removed it:
restored (and say "pud" not "pmd" in its pud_ERROR).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: exit_mmap need not reset
Hugh Dickins [Sun, 30 Oct 2005 01:15:58 +0000 (18:15 -0700)]
[PATCH] mm: exit_mmap need not reset

exit_mmap resets various mm_struct fields, but the mm is well on its way out,
and none of those fields matter by this point.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: unlink_file_vma, remove_vma
Hugh Dickins [Sun, 30 Oct 2005 01:15:57 +0000 (18:15 -0700)]
[PATCH] mm: unlink_file_vma, remove_vma

Divide remove_vm_struct into two parts: first anon_vma_unlink plus
unlink_file_vma, to unlink the vma from the list and tree by which rmap or
vmtruncate might find it; then remove_vma to close, fput and free.

The intention here is to do the anon_vma_unlink and unlink_file_vma earlier,
in free_pgtables before freeing any page tables: so we can be sure that any
page tables traversed by rmap and vmtruncate are stable (and other, ordinary
cases are stabilized by holding mmap_sem).

This will be crucial to traversing pgd,pud,pmd without page_table_lock.  But
testing the split-out patch showed that lifting the page_table_lock is
symbiotically necessary to make this change - the lock ordering is wrong to
move those unlinks into free_pgtables while it's under ptlock.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
19 years ago[PATCH] mm: remove_vma_list consolidation
Hugh Dickins [Sun, 30 Oct 2005 01:15:56 +0000 (18:15 -0700)]
[PATCH] mm: remove_vma_list consolidation

unmap_vma doesn't amount to much, let's put it inside unmap_vma_list.  Except
it doesn't unmap anything, unmap_region just did the unmapping: rename it to
remove_vma_list.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>