Steven Rostedt [Thu, 28 Jun 2012 00:46:14 +0000 (20:46 -0400)]
tracing: Remove NR_CPUS array from trace_iterator
Replace the NR_CPUS array of buffer_iter from the trace_iterator
with an allocated array. This will just create an array of
possible CPUS instead of the max number specified.
The use of NR_CPUS in that array caused allocation failures for
machines that were tight on memory. This did not cause any failures
to the system itself (no crashes), but caused unnecessary failures
for reading the trace files.
Added a helper function called 'trace_buffer_iter()' that returns
the buffer_iter item or NULL if it is not defined or the array was
not allocated. Some routines do not require the array
(tracing_open_pipe() for one).
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Namhyung Kim [Wed, 27 Jun 2012 00:41:39 +0000 (09:41 +0900)]
tracing/kvm: Use __print_hex() for kvm_emulate_insn tracepoint
The kvm_emulate_insn tracepoint used __print_insn()
for printing its instructions. However it makes the
format of the event hard to parse as it reveals TP
internals.
Fortunately, kernel provides __print_hex for almost
same purpose, we can use it instead of open coding
it. The user-space can be changed to parse it later.
That means raw kernel tracing will not be affected
by this change:
# cd /sys/kernel/debug/tracing/
# cat events/kvm/kvm_emulate_insn/format
name: kvm_emulate_insn
ID: 29
format:
...
print fmt: "%x:%llx:%s (%s)%s", REC->csbase, REC->rip, __print_hex(REC->insn, REC->len), \
__print_symbolic(REC->flags, { 0, "real" }, { (1 << 0) | (1 << 1), "vm16" }, \
{ (1 << 0), "prot16" }, { (1 << 0) | (1 << 2), "prot32" }, { (1 << 0) | (1 << 3), "prot64" }), \
REC->failed ? " failed" : ""
# echo 1 > events/kvm/kvm_emulate_insn/enable
# cat trace
# tracer: nop
#
# entries-in-buffer/entries-written: 2183/2183 #P:12
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
qemu-kvm-1782 [002] ...1 140.931636: kvm_emulate_insn: 0:
c102fa25:89 10 (prot32)
qemu-kvm-1781 [004] ...1 140.931637: kvm_emulate_insn: 0:
c102fa25:89 10 (prot32)
Link: http://lkml.kernel.org/n/tip-wfw6y3b9ugtey8snaow9nmg5@git.kernel.org
Link: http://lkml.kernel.org/r/1340757701-10711-2-git-send-email-namhyung@kernel.org
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: kvm@vger.kernel.org
Acked-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt [Mon, 18 Jun 2012 13:28:16 +0000 (09:28 -0400)]
tracing/selftest: Add a WARN_ON() if a tracer test fails
Add a WARN_ON() output on test failures so that they are easier to detect
in automated tests. Although, the WARN_ON() will not print if the test
causes the system to crash, obviously.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Robert Richter [Wed, 20 Jun 2012 16:39:27 +0000 (18:39 +0200)]
perf/x86: Fix section mismatch in uncore_pci_init()
Fix section mismatch in uncore_pci_init():
WARNING: vmlinux.o(.init.text+0x9246): Section mismatch in reference from the function uncore_pci_init() to the function .devexit.text:uncore_pci_remove()
The function __init uncore_pci_init() references
a function __devexit uncore_pci_remove().
[...]
Signed-off-by: Robert Richter <robert.richter@amd.com>
Cc: <a.p.zijlstra@chello.nl>
Cc: <zheng.z.yan@intel.com>
Link: http://lkml.kernel.org/r/20120620163927.GI5046@erda.amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Wed, 20 Jun 2012 11:41:42 +0000 (13:41 +0200)]
Merge tag 'perf-core-for-mingo' of git://git./linux/kernel/git/acme/linux into perf/core
Pull perf improvements from Arnaldo Carvalho de Melo:
* Replace event_name with perf_evsel__name, that handles the event
modifiers and doesn't use static variables.
* GTK browser improvements, from Namhyung Kim
* Fix possible NULL pointer deref in the TUI annotate browser, from
Samuel Liao
* Add sort by source file:line number, using addr2line.
* Allow printing histogram text snapshots at any point in top/report.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Samuel Liao [Tue, 5 Jun 2012 05:14:59 +0000 (13:14 +0800)]
perf annotate: Check null of sym pointer before using it
Sym may be NULL, and that will cause perf to crash.
Signed-off-by: Shan Wei <davidshan@tencent.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4FCD95D3.90209@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 13 Jun 2012 18:52:42 +0000 (15:52 -0300)]
perf evsel: Make some methods private
Now that __event_name is gone, no need to export __perf_evsel__[hs]w_name().
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-rpjnarbt83nu9uowrfatmy12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 11 Jun 2012 13:20:03 +0000 (15:20 +0200)]
perf tools: Remove unused evsel parameter from machine__resolve_callchain
Removing unused evsel parameter from machine__resolve_callchain
function. Plus related header file and callers changes.
The evsel parameter is unused since following commit:
perf callchain: Make callchain cursors TLS
commit
472606458f3e1ced5fe3cc5f04e90a6b5a4732cf
Author: Namhyung Kim <namhyung.kim@lge.com>
Date: Thu May 31 14:43:26 2012 +0900
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1339420814-7379-9-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 13 Jun 2012 14:53:37 +0000 (11:53 -0300)]
perf evsel: Reconstruct raw event with modifiers from perf_event_attr
I forgot to add the modifiers to raw events too, fix it.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-pi267j1aqqjti9rqh9qy4g58@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 16:45:00 +0000 (13:45 -0300)]
perf tools: Remove __event_name
Not needed anymore, the parsing code can just leave evsel->name as NULL
and the first call to perf_evsel__name() will do exactly what was being
pre-cached using __event_name().
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cn2eiijcinnc97buod8cs34m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 16:55:13 +0000 (13:55 -0300)]
perf tools: Don't access evsel->name directly
One needs to use perf_evsel__name() so that if needed the name gets
synthesized and stored in evsel->name, from where perf_evsel__name()
will serve from them on.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ml7zbenjmri9bghmrea0jm0d@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 16:35:44 +0000 (13:35 -0300)]
perf script: Replace __event_name uses with perf_evsel__name
No logic change, just remove one more user of __event_name().
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-e4f0vuy3283hmzfjjvkgm7fo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 15:34:58 +0000 (12:34 -0300)]
perf tools: Move all users of event_name to perf_evsel__name
So that we don't use global variables that could make us misreport event
names when having a multi window top, for instance.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-mccancovi1u0wdkg8ncth509@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Tue, 12 Jun 2012 13:29:12 +0000 (10:29 -0300)]
perf evsel: Handle all event types in perf_evsel__name
Now to convert all event_name users to perf_evsel__name.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-buuz0j0gynseglxa76r01rdn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 17:36:20 +0000 (14:36 -0300)]
perf tools: Reconstruct sw event with modifiers from perf_event_attr
[root@sandy ~]# perf record -e task-clock:u -a usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.482 MB perf.data (~21073 samples) ]
[root@sandy ~]#
Before:
[root@sandy ~]# perf evlist
task-clock
[root@sandy ~]#
After:
[root@sandy ~]# perf evlist
task-clock:u
[root@sandy ~]#
Ditto for other tools.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-97ltkmj7v23kyhflltf6iz5n@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 17:08:07 +0000 (14:08 -0300)]
perf tools: Reconstruct hw cache event with modifiers from perf_event_attr
[root@sandy ~]# perf record -a -e dTLB-load-misses:u usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.486 MB perf.data (~21216 samples) ]
Before:
[root@sandy ~]# perf evlist
dTLB-load-misses
[root@sandy ~]#
After:
[root@sandy ~]# perf evlist
dTLB-load-misses:u
[root@sandy ~]#
Ditto for other tools.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-7x1b0e6jthkr93lfjzsuakk5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 16:33:09 +0000 (13:33 -0300)]
perf evsel: Carve out event modifier formatting
From perf_evsel__hw_name, so that we can use it for the other kinds of
events (tracepoints, software, hw cache, etc).
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9gmd5wewsrvtny8tzxjfp471@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Thu, 7 Jun 2012 22:31:28 +0000 (19:31 -0300)]
perf hists browser: Implement printing snapshots to files
To avoid having to resort to --stdio, that expands everything, instead
allow the user to go on expanding the relevant callchains and then press
'P' to print that view.
As the hists browser is used for both static (report) and dynamic (top)
views, it prints to a 'perf.hists.N' sequence, i.e. multiple snapshots
can be taken in report and top.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wr9xx4ba0utrynu5j6wotd79@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Thu, 7 Jun 2012 21:23:31 +0000 (18:23 -0300)]
perf lib: Introduce rtrim
Remove the trailing whitespaces.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-8bxozh5lyixgjmziqaxo9675@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Tue, 29 May 2012 04:23:02 +0000 (13:23 +0900)]
perf ui/gtk: Use struct perf_error_ops
Define and use perf_gtk_eops to provide a GTK2 message dialog for error
reporting and a info_bar for warning.
As GtkInfoBar requires recent GTK+ libraries, provides a fallback
implementation using statusbar widget too.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-8-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Tue, 29 May 2012 04:23:01 +0000 (13:23 +0900)]
perf ui/gtk: Add GTK info_bar widget to browser window
The GtkInfoBar is a modern UI component to display messages without
bothering the main window. It'll be used for showing a warning message.
As the GtkInfoBar requires 2.18 (or newer) version of GTK+ library, add
availability check to Makefile too.
Suggested-by: Sunjin Yang <fan4326@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-7-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Tue, 29 May 2012 04:23:00 +0000 (13:23 +0900)]
perf ui/gtk: Add GTK statusbar widget to browser window
Add statusbar widget to display non-critical messages at the bottom of
the window. This can be used for showing a status change, warning or
help message.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-6-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Tue, 29 May 2012 04:22:59 +0000 (13:22 +0900)]
perf ui/gtk: Introduce struct perf_gtk_context
The struct perf_gtk_context is for tracking current state of GTK window
and/or other things. This is a preparation of next changes.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-5-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Namhyung Kim [Tue, 29 May 2012 04:22:58 +0000 (13:22 +0900)]
perf ui: Introduce struct perf_error_ops
The struct perf_error_ops is for flexible error logging.
We can register appropriate functions based on front-end.
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-4-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Arnaldo Carvalho de Melo [Wed, 30 May 2012 13:33:24 +0000 (10:33 -0300)]
perf tools: Add sort by src line/number
Using addr2line for now, requires debuginfo, needs more work to support
detached debuginfo, aka foo-debuginfo packages.
Example:
[root@sandy ~]# perf record -a sleep 3
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.555 MB perf.data (~24236 samples) ]
[root@sandy ~]# perf report -s dso,srcline 2>&1 | grep -v ^# | head -5
22.41% [kernel.kallsyms] /home/git/linux/drivers/idle/intel_idle.c:280
4.79% [kernel.kallsyms] /home/git/linux/drivers/cpuidle/cpuidle.c:148
4.78% [kernel.kallsyms] /home/git/linux/arch/x86/include/asm/atomic64_64.h:121
4.49% [kernel.kallsyms] /home/git/linux/kernel/sched/core.c:1690
4.30% [kernel.kallsyms] /home/git/linux/include/linux/seqlock.h:90
[root@sandy ~]#
[root@sandy ~]# perf top -U -s dso,symbol,srcline
Samples: 1K of event 'cycles', Event count (approx.):
589617389
18.66% [kernel] [k] copy_user_generic_unrolled /home/git/linux/arch/x86/lib/copy_user_64.S:143
7.83% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:39
6.59% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:38
3.66% [kernel] [k] page_fault /home/git/linux/arch/x86/kernel/entry_64.S:1379
3.25% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:40
3.12% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:37
2.74% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:36
2.39% [kernel] [k] clear_page /home/git/linux/arch/x86/lib/clear_page_64.S:43
2.12% [kernel] [k] ioread32 /home/git/linux/lib/iomap.c:90
1.51% [kernel] [k] copy_user_generic_unrolled /home/git/linux/arch/x86/lib/copy_user_64.S:144
1.19% [kernel] [k] copy_user_generic_unrolled /home/git/linux/arch/x86/lib/copy_user_64.S:154
Suggested-by: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-pdmqbng9twz06jzkbgtuwbp8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Peter Zijlstra [Sat, 16 Jun 2012 12:45:49 +0000 (14:45 +0200)]
perf/x86: Lowercase uncore PMU event names
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-ucnds8gkve4x3s4biuukyph3@git.kernel.org
[ Trivial build fix ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jiri Olsa [Fri, 15 Jun 2012 06:31:42 +0000 (14:31 +0800)]
perf/tool: Add automated test for pure terms parsing
Adding automated test for parsing terms out of the event grammar.
Also slightly changing current event parsing test functions to
follow up more generic namespace.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-14-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Zheng Yan [Fri, 15 Jun 2012 06:31:41 +0000 (14:31 +0800)]
perf/tool: Add PMU event alias support
Add support to specify alias term within the event description.
The definition of pmu event alias is located at:
${sysfs_mount}/bus/event_source/devices/${pmu}/events/
Each file in the 'events' directory defines a event alias. Its contents
are like:
config=1,config1=2
Using pmu event alias, an event can be now specified like:
uncore/CLOCKTICKS/ or uncore/event=CLOCKTICKS/
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
[ Cleaned it up. ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1339741902-8449-13-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jiri Olsa [Fri, 15 Jun 2012 06:31:40 +0000 (14:31 +0800)]
perf/tool: Add support to reuse event grammar to parse out terms
We want to reuse the event grammar for parsing aliased terms.
The obvious reason is we dont need to add new code when there's
already support for this in event grammar.
Doing this by adding terms and event start entries into event
parse grammar. The grammar forks on the begining based on the
starting token, which is supplied via bison interface into the
lexer. The lexer then returns the starting token as the first
token, thus making the grammar switch accordingly.
Currently 2 starting tokens/grammars are supported:
PE_START_TERMS, PE_START_EVENTS
The PE_START_TERMS related grammar uses 'event_config' part
of the grammar for term parsing.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-12-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Zheng Yan [Fri, 15 Jun 2012 06:31:39 +0000 (14:31 +0800)]
perf/tool: Make the event parser re-entrant
Make the event parser reentrant by creating separate
scanner for each parsing. The scanner is passed to the bison
as and argument to the lexer.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
[ Cleaned up the patch. ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-11-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jiri Olsa [Fri, 15 Jun 2012 06:31:38 +0000 (14:31 +0800)]
perf/tool: Use data struct for arg passing in event parse function
Moving all the bison arguments into the structure. In upcomming
patches we are going to:
- add more arguments
- reuse the grammer for term parsing
so it's more clear to pack/separate related arguments.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-10-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:37 +0000 (14:31 +0800)]
perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support
The uncore subsystem in Sandy Bridge-EP consists of 8 components:
Ubox, Cacheing Agent, Home Agent, Memory controller, Power Control,
QPI Link Layer, R2PCIe, R3QPI.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1339741902-8449-9-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:36 +0000 (14:31 +0800)]
perf: Add generic PCI uncore PMU device support
This patch adds generic support for uncore PMUs presented as
PCI devices. (These come in addition to the CPU/MSR based
uncores.)
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-8-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:35 +0000 (14:31 +0800)]
perf/x86: Add Intel Nehalem and Sandy Bridge uncore PMU support
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1339741902-8449-7-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:34 +0000 (14:31 +0800)]
perf/x86: Add generic Intel uncore PMU support
This patch adds the generic Intel uncore PMU support, including helper
functions that add/delete uncore events, a hrtimer that periodically
polls the counters to avoid overflow and code that places all events
for a particular socket onto a single cpu.
The code design is based on the structure of Sandy Bridge-EP's uncore
subsystem, which consists of a variety of components, each component
contains one or more "boxes".
(Tooling support follows in the next patches.)
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1339741902-8449-6-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:33 +0000 (14:31 +0800)]
perf: Introduce perf_pmu_migrate_context()
Originally from Peter Zijlstra. The helper migrates perf events
from one cpu to another cpu.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-5-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:32 +0000 (14:31 +0800)]
perf: Allow the PMU driver to choose the CPU on which to install events
Allow the pmu->event_init callback to change event->cpu, so the PMU driver
can choose the CPU on which to install events.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-4-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:31 +0000 (14:31 +0800)]
perf: Avoid race between cpu hotplug and installing event
perf_event_open() requires the cpu on which to install event is online,
but the cpu can go offline after perf_event_open checks that. Add a
get_online_cpus()/put_online_cpus() pair to avoid the race.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-3-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yan, Zheng [Fri, 15 Jun 2012 06:31:30 +0000 (14:31 +0800)]
perf: Export perf_assign_events()
Export perf_assign_events() so the uncore code can use it to
schedule events.
Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1339741902-8449-2-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Mon, 18 Jun 2012 09:47:58 +0000 (11:47 +0200)]
Merge branch 'perf/urgent' into perf/core
Merge in all fixes before applying more changes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Salman Qazi [Thu, 14 Jun 2012 22:31:09 +0000 (15:31 -0700)]
perf: Use css_tryget() to avoid propping up css refcount
An rmdir pushes css's ref count to zero. However, if the associated
directory is open at the time, the dentry ref count is non-zero. If
the fd for this directory is then passed into perf_event_open, it
does a css_get(). This bounces the ref count back up from zero. This
is a problem by itself. But what makes it turn into a crash is the
fact that we end up doing an extra dput, since we perform a dput
when css_put sees the ref count go down to zero.
css_tryget() does not fall into that trap. So, we use that instead.
Reproduction test-case for the bug:
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/unistd.h>
#include <linux/perf_event.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#define PERF_FLAG_PID_CGROUP (1U << 2)
int perf_event_open(struct perf_event_attr *hw_event_uptr,
pid_t pid, int cpu, int group_fd, unsigned long flags) {
return syscall(__NR_perf_event_open,hw_event_uptr, pid, cpu,
group_fd, flags);
}
/*
* Directly poke at the perf_event bug, since it's proving hard to repro
* depending on where in the kernel tree. what moved?
*/
int main(int argc, char **argv)
{
int fd;
struct perf_event_attr attr;
memset(&attr, 0, sizeof(attr));
attr.exclude_kernel = 1;
attr.size = sizeof(attr);
mkdir("/dev/cgroup/perf_event/blah", 0777);
fd = open("/dev/cgroup/perf_event/blah", O_RDONLY);
perror("open");
rmdir("/dev/cgroup/perf_event/blah");
sleep(2);
perf_event_open(&attr, fd, 0, -1, PERF_FLAG_PID_CGROUP);
perror("perf_event_open");
close(fd);
return 0;
}
Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20120614223108.1025.2503.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Robert Richter [Fri, 15 Jun 2012 17:06:44 +0000 (19:06 +0200)]
perf/x86/amd: Fix RDPMC index calculation for AMD family 15h
The RDPMC index calculation is wrong for AMD family 15h
(X86_FEATURE_ PERFCTR_CORE set). This leads to a #GP when
accessing the counter:
Pid: 2237, comm: syslog-ng Not tainted 3.5.0-rc1-perf-x86_64
-standard-g130ff90 #135 AMD Pike/Pike
RIP: 0010:[<
ffffffff8100dc33>] [<
ffffffff8100dc33>] x86_perf_event_update+0x27/0x66
While the msr address offset is (index << 1) we must use index to
select the correct rdpmc.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vince Weaver <vweaver1@eecs.utk.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Mon, 18 Jun 2012 08:57:51 +0000 (10:57 +0200)]
Merge branch 'tip/perf/core' of git://git./linux/kernel/git/rostedt/linux-trace into perf/core
Pull ftrace robustization fixes from Steve Rostedt.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:44:01 +0000 (17:44 +0200)]
uprobes: Remove the unnecessary initialization in add_utask()
Trivial cleanup. No need to nullify ->active_uprobe after
kzalloc().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154401.GA9633@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:59 +0000 (17:43 +0200)]
uprobes: __copy_insn() needs "loff_t offset"
1. __copy_insn() needs "loff_t offset", not "unsigned long",
to read the file.
2. use pgoff_t for "idx" and remove the unnecessary typecast.
3. fix the typo, "&=" is not what we want
4. can't resist, rename off1 to off.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154359.GA9625@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:55 +0000 (17:43 +0200)]
uprobes: Don't use loff_t for the valid virtual address
loff_t looks confusing when it is used for the virtual address.
Change map_info and install_breakpoint/remove_breakpoint paths
to use "unsigned long".
The patch doesn't change vma_address(), it can't return "long"
because it is used to verify the mapping. But probably this
needs some cleanups too.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Arapov <anton@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154355.GA9622@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:53 +0000 (17:43 +0200)]
uprobes: Simplify the usage of uprobe->pending_list
uprobe->pending_list is only used to create the temporary list,
it has no meaning after we drop uprobes_mmap_hash(inode).
No need to initialize this node or remove it from tmp_list, and
we can use list_for_each_entry().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154353.GA9614@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:50 +0000 (17:43 +0200)]
uprobes: Move BUG_ON(UPROBE_SWBP_INSN_SIZE) from write_opcode() to install_breakpoint()
write_opcode() ensures that UPROBE_SWBP_INSN doesn't cross the
page boundary. This looks a bit confusing, the check does not
depend on vaddr and it is enough to do it only once right after
install_breakpoint()->arch_uprobe_analyze_insn().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154350.GA9611@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:47 +0000 (17:43 +0200)]
uprobes: No need to re-check vma_address() in write_opcode()
write_opcode() is called by register_for_each_vma() and
uprobe_mmap() paths. In both cases the caller has already
verified this vaddr under mmap_sem, no need to re-check.
Note also that this check is wrong anyway, we should not
truncate loff_t returned by vma_address() if we do not trust
this mapping.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154347.GA9604@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:44 +0000 (17:43 +0200)]
uprobes: Copy_insn() should not return -ENOMEM if __copy_insn() fails
copy_insn() returns -ENOMEM if the first __copy_insn() fails,
it should return the correct error code.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154344.GA9601@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:42 +0000 (17:43 +0200)]
uprobes: Copy_insn() shouldn't depend on mm/vma/vaddr
1. copy_insn() doesn't need "addr", it can use uprobe->offset.
Remove this argument.
2. Change copy_insn/__copy_insn to accept "struct file*" instead
of vma.
copy_insn() is called only once and mm/vma/vaddr are random, it
shouldn't depend on them.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154342.GA9598@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Fri, 15 Jun 2012 15:43:39 +0000 (17:43 +0200)]
uprobes: Document uprobe_register() vs uprobe_mmap() race
Because the mind is treacherous and makes us forget we need to
write stuff down.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120615154339.GA9591@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:36 +0000 (17:43 +0200)]
uprobes: Change build_map_info() to try kmalloc(GFP_NOWAIT) first
build_map_info() doesn't allocate the memory under i_mmap_mutex
to avoid the deadlock with page reclaim. But it can try
GFP_NOWAIT first, it should work in the likely case and thus we
almost never need the pre-alloc-and-retry path.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20120615154336.GA9588@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:33 +0000 (17:43 +0200)]
uprobes: Rework register_for_each_vma() to make it O(n)
Currently register_for_each_vma() is O(n ** 2) + O(n ** 3),
every time find_next_vma_info() "restarts" the
vma_prio_tree_foreach() loop and each iteration rechecks the
whole try_list. This also means that try_list can grow
"indefinitely" if register/unregister races with munmap/mmap
activity even if the number of mapping is bounded at any time.
With this patch register_for_each_vma() builds the list of
mm/vaddr structures only once and does install_breakpoint() for
each entry.
We do not care about the new mappings which can be created after
build_map_info() drops mapping->i_mmap_mutex, uprobe_mmap()
should do its work.
Note that we do not allocate map_info under i_mmap_mutex, this
can deadlock with page reclaim (but see the next patch). So we
use 2 lists, "curr" which we are going to return, and "prev"
which holds the already allocated memory. The main loop deques
the entry from "prev" (initially it is empty), and if "prev"
becomes empty again it counts the number of entries we need to
pre-allocate outside of i_mmap_mutex.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20120615154333.GA9581@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:31 +0000 (17:43 +0200)]
uprobes: Install_breakpoint() should fail if is_swbp_insn() == T
install_breakpoint() returns -EEXIST if is_swbp_insn(orig_insn)
== T, the caller treats this code as success.
This is doubly wrong. The successful return should set
UPROBE_COPY_INSN, but the real problem is that it shouldn't
succeed. If the probed insn is int3 the application should get
SIGTRAP, this won't happen with uprobe.
Probably we can fix this, we can add the UPROBE_SHARED_BP flag
and teach handle_swbp/set_orig_insn to handle this case
correctly. But this needs some complications and we have other
insns which can't be probed, lets make a simple fix for now.
I think this needs a cleanup. UPROBE_COPY_INSN should die,
copy_insn() should be called by alloc_uprobe().
arch_uprobe_analyze_insn() depends on ->mm (ia32_compat) but it
is called only once.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154331.GA9578@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:28 +0000 (17:43 +0200)]
uprobes: Write_opcode()->__replace_page() can race with try_to_unmap()
write_opcode() gets old_page via get_user_pages() and then calls
__replace_page() which assumes that this old_page is still
mapped after pte_offset_map_lock().
This is not true if this old_page was already try_to_unmap()'ed,
and in this case everything __replace_page() does with old_page
is wrong. Just for example, put_page() is not balanced.
I think it is possible to teach __replace_page() to handle this
unlikely case correctly, but this patch simply changes it to use
page_check_address() and return -EAGAIN if it fails. The caller
should notice this error code and retry.
Note: write_opcode() asks for the cleanups, I'll try to do this
in a separate patch.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154328.GA9571@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:25 +0000 (17:43 +0200)]
uprobes: __copy_insn() should ensure a_ops->readpage != NULL
__copy_insn() blindly calls read_mapping_page(), this will crash
the kernel if ->readpage == NULL, add the necessary check. For
example, hugetlbfs_aops->readpage is NULL. Perhaps we should
change read_mapping_page() instead.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154325.GA9568@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Oleg Nesterov [Fri, 15 Jun 2012 15:43:22 +0000 (17:43 +0200)]
uprobes: Valid_vma() should reject VM_HUGETLB
__replace_page() obviously can't work with the hugetlbfs
mappings, uprobe_register() will likely crash the kernel. Change
valid_vma() to check VM_HUGETLB as well.
As for PageTransHuge() no need to worry, vma->vm_file != NULL.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120615154322.GA9561@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Fri, 15 Jun 2012 19:02:16 +0000 (21:02 +0200)]
Merge tag 'perf-urgent-for-mingo' of git://git./linux/kernel/git/acme/linux into perf/urgent
Pull perf fixes from Arnaldo Carvalho de Melo:
* Set name of tracepoints when reading the perf.data headers, so that
we don't end up using the local ones, from /sys.
* Fix default output file for perf stat, from Stephane Eranian.
* Fix endian handling of features bitmask in perf.data header, from David Ahern.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Steven Rostedt [Fri, 1 Jun 2012 01:40:05 +0000 (21:40 -0400)]
tracing: Register the ftrace internal events during early boot
All trace events including ftrace internel events (like trace_printk
and function tracing), register functions that describe how to print
their output. The events may be recorded as soon as the ring buffer
is allocated, but they are just raw binary in the buffer. The mapping
of event ids to how to print them are held within a structure that
is registered on system boot.
If a crash happens in boot up before these functions are registered
then their output (via ftrace_dump_on_oops) will be useless:
Dumping ftrace buffer:
---------------------------------
<...>-1 0.... 319705us : Unknown type 6
---------------------------------
This can be quite frustrating for a kernel developer trying to see
what is going wrong.
There's no reason to register them so late in the boot up process.
They can be registered by early_initcall().
Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt [Fri, 1 Jun 2012 01:28:58 +0000 (21:28 -0400)]
tracing: Add comments for the other bits of ftrace_event_call.flags
TRACE_EVENT_FL_ENABLED_BIT,
TRACE_EVENT_FL_FILTERED_BIT,
TRACE_EVENT_FL_RECORDED_CMD_BIT,
Have comments about what they are, but:
TRACE_EVENT_FL_CAP_ANY_BIT,
TRACE_EVENT_FL_NO_SET_FILTER_BIT,
TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
do not, making them second class citizens. To prevent another
class warfare, these bits have protested for their right to be
commented. And By Golly! I'll give them what they want!
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Borislav Petkov [Thu, 29 Mar 2012 17:11:40 +0000 (19:11 +0200)]
ftrace: Remove a superfluous check
register_ftrace_function() checks ftrace_disabled and calls
__register_ftrace_function which does it again.
Drop the first check and add the unlikely hint to the second one. Also,
drop the label as John correctly notices.
No functional change.
Link: http://lkml.kernel.org/r/20120329171140.GE6409@aftab
Cc: Borislav Petkov <bp@amd64.org>
Cc: John Kacur <jkacur@redhat.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Don Zickus [Wed, 13 Jun 2012 13:35:48 +0000 (09:35 -0400)]
watchdog: Quiet down the boot messages
A bunch of bugzillas have complained how noisy the nmi_watchdog
is during boot-up especially with its expected failure cases
(like virt and bios resource contention).
This is my attempt to quiet them down and keep it less confusing
for the end user. What I did is print the message for cpu0 and
save it for future comparisons. If future cpus have an
identical message as cpu0, then don't print the redundant info.
However, if a future cpu has a different message, happily print
that loudly.
Before the change, you would see something like:
..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a
Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver.
... version: 2
... bit width: 40
... generic registers: 2
... value mask:
000000ffffffffff
... max period:
000000007fffffff
... fixed-purpose events: 3
... event mask:
0000000700000003
NMI watchdog enabled, takes one hw-pmu counter.
Booting Node 0, Processors #1
NMI watchdog enabled, takes one hw-pmu counter.
#2
NMI watchdog enabled, takes one hw-pmu counter.
#3 Ok.
NMI watchdog enabled, takes one hw-pmu counter.
Brought up 4 CPUs
Total of 4 processors activated (22607.24 BogoMIPS).
After the change, it is simplified to:
..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
CPU0: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz stepping 0a
Performance Events: PEBS fmt0+, Core2 events, Intel PMU driver.
... version: 2
... bit width: 40
... generic registers: 2
... value mask:
000000ffffffffff
... max period:
000000007fffffff
... fixed-purpose events: 3
... event mask:
0000000700000003
NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
Booting Node 0, Processors #1 #2 #3 Ok.
Brought up 4 CPUs
V2: little changes based on Joe Perches' feedback
V3: printk cleanup based on Ingo's feedback; checkpatch fix
V4: keep printk as one long line
V5: Ingo fix ups
Reported-and-tested-by: Nathan Zimmer <nzimmer@sgi.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: nzimmer@sgi.com
Cc: joe@perches.com
Link: http://lkml.kernel.org/r/1339594548-17227-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Stephane Eranian [Mon, 11 Jun 2012 13:44:26 +0000 (15:44 +0200)]
perf/x86: Fix broken LBR fixup code
I noticed that the LBR fixups were not working anymore
on programs where they used to. I tracked this down to
a recent change to copy_from_user_nmi():
db0dc75d640 ("perf/x86: Check user address explicitly in copy_from_user_nmi()")
This commit added a call to __range_not_ok() to the
copy_from_user_nmi() routine. The problem is that the logic
of the test must be reversed. __range_not_ok() returns 0 if the
range is VALID. We want to return early from copy_from_user_nmi()
if the range is NOT valid.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arun Sharma <asharma@fb.com>
Link: http://lkml.kernel.org/r/20120611134426.GA7542@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Arnaldo Carvalho de Melo [Mon, 11 Jun 2012 22:03:32 +0000 (19:03 -0300)]
perf tools: Fix synthesizing tracepoint names from the perf.data headers
We need to use the per event info snapshoted at record time to
synthesize the events name, so do it just after reading the perf.data
headers, when we already processed the /sys events data, otherwise we'll
end up using the local /sys that only by sheer luck will have the same
tracepoint ID -> real event association.
Example:
# uname -a
Linux felicio.ghostprotocols.net 3.4.0-rc5+ #1 SMP Sat May 19 15:27:11 BRT 2012 x86_64 x86_64 x86_64 GNU/Linux
# perf record -e sched:sched_switch usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.015 MB perf.data (~648 samples) ]
# cat /t/events/sched/sched_switch/id
279
# perf evlist -v
sched:sched_switch: sample_freq=1, type: 2, config: 279, size: 80, sample_type: 1159, read_format: 7, disabled: 1, inherit: 1, mmap: 1, comm: 1, enable_on_exec: 1, sample_id_all: 1, exclude_guest: 1
#
So on the above machine the sched:sched_switch has tracepoint id 279, but on
the machine were we'll analyse it it has a different id:
$ cat /t/events/sched/sched_switch/id
56
$ perf evlist -i /tmp/perf.data
kmem:mm_balancedirty_writeout
$ cat /t/events/kmem/mm_balancedirty_writeout/id
279
With this fix:
$ perf evlist -i /tmp/perf.data
sched:sched_switch
Reported-by: Dmitry Antipov <dmitry.antipov@linaro.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-auwks8fpuhmrdpiefs55o5oz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Stephane Eranian [Tue, 15 May 2012 11:11:11 +0000 (13:11 +0200)]
perf stat: Fix default output file
The following commit:
commit
56f3bae70638b33477a6015fd362ccfe354fd3ee
Author: Jim Cromie <jim.cromie@gmail.com>
Date: Wed Sep 7 17:14:00 2011 -0600
perf stat: Add --log-fd <N> option to redirect stderr elsewhere
introduced a bug in the way perf stat outputs the results by default,
i.e., without the --log-fd or --output option. It would default to
writing to file descriptor 0, i.e., stdin. Writing to stdin is allowed
and is equivalent to writing to stdout. However, there is a major
difference for any script that was already capturing the output of perf
stat via redirection:
perf stat >/tmp/log .... or perf stat 2>/tmp/log ....
They would not capture anything anymore. They would have to do:
perf stat 0>/tmp/log ...
This breaks compatibility with existing scripts and does not look very
natural.
This patch fixes the problem by looking at output_fd only when it was
modified by user (> 0). It also checks that the value if positive.
Passing --log-fd 0 is ignored.
I would also argue that defaulting to stderr for the results is not the
right thing to do, though this patch does not address this specific
issue.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jim Cromie <jim.cromie@gmail.com>
Link: http://lkml.kernel.org/r/20120515111111.GA9870@quad
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
David Ahern [Fri, 8 Jun 2012 14:47:51 +0000 (11:47 -0300)]
perf tools: Fix endianity swapping for adds_features bitmask
Based on Jiri's latest attempt:
https://lkml.org/lkml/2012/5/16/61
Basically, adds_features should be byte swapped assuming unsigned
longs are either 8-bytes (u64) or 4-bytes (u32).
Fixes 32-bit ppc dumping 64-bit x86 feature data:
========
captured on: Sun May 20 19:23:23 2012
hostname : nxos-vdc-dev3
os release : 3.4.0-rc7+
perf version : 3.4.rc4.137.g978da3
arch : x86_64
nrcpus online : 16
nrcpus avail : 16
cpudesc : Intel(R) Xeon(R) CPU E5540 @ 2.53GHz
cpuid : GenuineIntel,6,26,5
total memory :
24680324 kB
...
Verified 64-bit x86 can still dump feature data for 32-bit ppc.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/4FBBB539.5010805@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Shuah Khan [Mon, 11 Jun 2012 03:13:41 +0000 (21:13 -0600)]
perf/x86: Convert obsolete simple_strtoul() usage to kstrtoul()
Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1339384421.3025.8.camel@lorien2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Mon, 11 Jun 2012 08:51:35 +0000 (10:51 +0200)]
Merge tag 'v3.5-rc2' into perf/core
Merge in Linux 3.5-rc2 - to pick up fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Sat, 9 Jun 2012 01:40:09 +0000 (18:40 -0700)]
Linux 3.5-rc2
David Rientjes [Fri, 8 Jun 2012 20:21:26 +0000 (13:21 -0700)]
mm, oom: fix badness score underflow
If the privileges given to root threads (3% of allowable memory) or a
negative value of /proc/pid/oom_score_adj happen to exceed the amount of
rss of a thread, its badness score overflows as a result of commit
a7f638f999ff ("mm, oom: normalize oom scores to oom_score_adj scale only
for userspace").
Fix this by making the type signed and return 1, meaning the thread is
still eligible for kill, if the value is negative.
Reported-by: Dave Jones <davej@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 8 Jun 2012 21:59:29 +0000 (14:59 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar.
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix the relax_domain_level boot parameter
sched: Validate assumptions in sched_init_numa()
sched: Always initialize cpu-power
sched: Fix domain iteration
sched/rt: Fix lockdep annotation within find_lock_lowest_rq()
sched/numa: Load balance between remote nodes
sched/x86: Calculate booted cores after construction of sibling_mask
Randy Dunlap [Fri, 8 Jun 2012 20:18:33 +0000 (13:18 -0700)]
sched/fair: fix lots of kernel-doc warnings
Fix lots of new kernel-doc warnings in kernel/sched/fair.c:
Warning(kernel/sched/fair.c:3625): No description found for parameter 'env'
Warning(kernel/sched/fair.c:3625): Excess function parameter 'sd' description in 'update_sg_lb_stats'
Warning(kernel/sched/fair.c:3735): No description found for parameter 'env'
Warning(kernel/sched/fair.c:3735): Excess function parameter 'sd' description in 'update_sd_pick_busiest'
Warning(kernel/sched/fair.c:3735): Excess function parameter 'this_cpu' description in 'update_sd_pick_busiest'
.. more warnings
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 8 Jun 2012 21:53:06 +0000 (14:53 -0700)]
Revert "drm/i915/crt: Do not rely upon the HPD presence pin"
This reverts commit
9e612a008fa7fe493a473454def56aa321479495.
It incorrectly finds VGA connectors where none are attached, apparently
not noticing that nothing replied to the EDID queries, and happily using
the default EDID modes that have nothing to do with actual hardware.
That in turn then causes X to fall down to the lowest common
denominator, which is usually the default 1024x768 mode that is in the
default EDID and pretty much anything supports).
I'd suggest that if not relying on the HDP pin, the code should at least
check whether it gets valid EDID data back, rather than just assume
there's something on the VGA connector.
Cc: Dave Airlie <airlied@linux.ie>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 8 Jun 2012 18:15:31 +0000 (11:15 -0700)]
Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4
Pull ext4 bug fixes from Theodore Ts'o:
"This update contains two bug fixes, both destined for the stable tree.
Perhaps the most important is one which fixes ext4 when used with file
systems originally formatted for use with ext3, but then later
converted to take advantage of ext4."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: don't set i_flags in EXT4_IOC_SETFLAGS
ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg
Linus Torvalds [Fri, 8 Jun 2012 18:06:01 +0000 (11:06 -0700)]
Merge branch 'merge' of git://git./linux/kernel/git/paulus/powerpc
Pull powerpc fixes from Paul Mackerras:
"Two small fixes for powerpc:
- a fix for a regression since 3.2 that causes 4-second (or longer)
pauses
- a fix for a potential oops when loading kernel modules on 32-bit
embedded systems."
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: Fix kernel panic during kernel module load
powerpc/time: Sanity check of decrementer expiration is necessary
Linus Torvalds [Fri, 8 Jun 2012 18:04:06 +0000 (11:04 -0700)]
Merge tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS fixes from Artem Bityutskiy:
"Fix UBI and UBIFS - they refuse to work without debugfs. This was
broken by the 3.5-rc1 UBI/UBIFS changes when we removed the debugging
Kconfig switches.
Also, correct locking in 'ubi_wl_flush()' - it was extended to support
flushing a specific LEB in 3.5-rc1, and the locking was sub-optimal."
* tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs:
UBI: correct ubi_wl_flush locking
UBIFS: fix debugfs-less systems support
UBI: fix debugfs-less systems support
Linus Torvalds [Fri, 8 Jun 2012 17:34:03 +0000 (10:34 -0700)]
Revert "vfs: stop d_splice_alias creating directory aliases"
This reverts commit
7732a557b1342c6e6966efb5f07effcf99f56167 (and commit
3f50fff4dace23d3cfeb195d5cd4ee813cee68b7, which was a follow-up
cleanup).
We're chasing an elusive bug that Dave Jones can apparently reproduce
using his system call fuzzer tool, and that looks like some kind of
locking ordering problem on the directory i_mutex chain. Our i_mutex
locking is rather complex, and depends on the topological ordering of
the directories, which is why we have been very wary of splicing
directory entries around.
Of course, we really don't want to ever see aliased unconnected
directories anyway, so none of this should ever happen, but this revert
aims to basically get us back to a known older state.
Bruce points to some of the previous discussion at
http://marc.info/?i=<
20110310105821.GE22723@ZenIV.linux.org.uk>
and in particular a long post from Neil:
http://marc.info/?i=<
20110311150749.
2fa2be66@notabene.brown>
It should be noted that it's possible that Dave's problems come from
other changes altohgether, including possibly just the fact that Dave
constantly is teachning his fuzzer new tricks. So what appears to be a
new bug could in fact be an old one that just gets newly triggered, but
reverting these patches as "still under heavy discussion" is the right
thing regardless.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 8 Jun 2012 16:26:55 +0000 (09:26 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Fix section mismatch warnings on 32-bit
x86/uv: Fix UV2 BAU legacy mode
x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space
x86, efi stub: Add .reloc section back into image
x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs
x86/reboot: Fix a warning message triggered by stop_other_cpus()
x86/intel/moorestown: Change intel_scu_devices_create() to __devinit
x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init()
x86/gart: Fix kmemleak warning
x86: mce: Add the dropped timer interval init back
x86/mce: Fix the MCE poll timer logic
Linus Torvalds [Fri, 8 Jun 2012 16:14:46 +0000 (09:14 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"A bit larger than what I'd wish for - half of it is due to hw driver
updates to Intel Ivy-Bridge which info got recently released,
cycles:pp should work there now too, amongst other things. (but we
are generally making exceptions for hardware enablement of this type.)
There are also callchain fixes in it - responding to mostly
theoretical (but valid) concerns. The tooling side sports perf.data
endianness/portability fixes which did not make it for the merge
window - and various other fixes as well."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
perf/x86: Check user address explicitly in copy_from_user_nmi()
perf/x86: Check if user fp is valid
perf: Limit callchains to 127
perf/x86: Allow multiple stacks
perf/x86: Update SNB PEBS constraints
perf/x86: Enable/Add IvyBridge hardware support
perf/x86: Implement cycles:p for SNB/IVB
perf/x86: Fix Intel shared extra MSR allocation
x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix
perf: Remove duplicate invocation on perf_event_for_each
perf uprobes: Remove unnecessary check before strlist__delete
perf symbols: Check for valid dso before creating map
perf evsel: Fix 32 bit values endianity swap for sample_id_all header
perf session: Handle endianity swap on sample_id_all header data
perf symbols: Handle different endians properly during symbol load
perf evlist: Pass third argument to ioctl explicitly
perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP
perf tools: Make --version show kernel version instead of pull req tag
perf tools: Check if callchain is corrupted
perf callchain: Make callchain cursors TLS
...
Linus Torvalds [Fri, 8 Jun 2012 16:12:21 +0000 (09:12 -0700)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm intel and exynos fixes from Dave Airlie:
"A bunch of fixes for Intel and exynos, nothing too major, a new intel
PCI ID, and a fix for CRT detection."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
char/agp: add another Ironlake host bridge
drm/i915: fix up ivb plane 3 pageflips
drm/exynos: fixed blending for hdmi graphic layer
drm/exynos: Remove dummy encoder get_crtc operation implementation
drm/exynos: Keep a reference to frame buffer GEM objects
drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
drm/exynos: fixed size type.
drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}
drm/i915: hold forcewake around ring hw init
drm/i915: Mark the ringbuffers as being in the GTT domain
drm/i915/crt: Do not rely upon the HPD presence pin
drm/i915: Reset last_retired_head when resetting ring
Linus Torvalds [Fri, 8 Jun 2012 16:11:33 +0000 (09:11 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull leap second timer fix from Thomas Gleixner.
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond
Linus Torvalds [Fri, 8 Jun 2012 16:10:35 +0000 (09:10 -0700)]
Merge tag 'moduleparam-for-linus' of git://git./linux/kernel/git/rusty/linux-2.6-for-linus
Pull minor module param fixes from Rusty Russell:
"One bugfix for multiple moduleparam levels, one removal of overzealous
printk."
* tag 'moduleparam-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
init: Drop initcall level output
module_param: stop double-calling parameters.
Ingo Molnar [Fri, 8 Jun 2012 10:23:22 +0000 (12:23 +0200)]
Merge branch 'tip/perf/urgent' of git://git./linux/kernel/git/rostedt/linux-trace into perf/urgent
Pull brown paper bag fix from Steve Rostedt.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ananth N Mavinakayanahalli [Fri, 8 Jun 2012 09:32:57 +0000 (15:02 +0530)]
uprobes: Pass probed vaddr to arch_uprobe_analyze_insn()
On RISC architectures like powerpc, instructions are fixed size.
Instruction analysis on such platforms is just a matter of
(insn % 4). Pass the vaddr at which the uprobe is to be inserted so
that arch_uprobe_analyze_insn() can flag misaligned registration
requests.
Signed-off-by: Ananth N Mavinakaynahalli <ananth@in.ibm.com>
Cc: michael@ellerman.id.au
Cc: antonb@thinktux.localdomain
Cc: Paul Mackerras <paulus@samba.org>
Cc: benh@kernel.crashing.org
Cc: peterz@infradead.org
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: oleg@redhat.com
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20120608093257.GG13409@in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Don Zickus [Wed, 6 Jun 2012 14:05:42 +0000 (10:05 -0400)]
x86/nmi: Fix section mismatch warnings on 32-bit
It was reported that compiling for 32-bit caused a bunch of
section mismatch warnings:
VDSOSYM arch/x86/vdso/vdso32-syms.lds
LD arch/x86/vdso/built-in.o
LD arch/x86/built-in.o
WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in
reference from the variable test_nmi_ipi_callback_na.10451 to
the function .init.text:test_nmi_ipi_callback() [...]
WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in
reference from the variable nmi_unk_cb_na.10399 to the function
.init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399
references the function __init nmi_unk_cb() [...]
Both of these are attributed to the internal representation of
the nmiaction struct created during register_nmi_handler. The
reason for this is that those structs are not defined in the
init section whereas the rest of the code in nmi_selftest.c is.
To resolve this, I created a new #define,
register_nmi_handler_initonly, that tags the struct as
__initdata to resolve the mismatch. This #define should only be
used in rare situations where the register/unregister is called
during init of the kernel.
Big thanks to Jan Beulich for decoding this for me as I didn't
have a clue what was going on.
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Steffen Rumler [Wed, 6 Jun 2012 14:37:17 +0000 (16:37 +0200)]
powerpc: Fix kernel panic during kernel module load
This fixes a problem which can causes kernel oopses while loading
a kernel module.
According to the PowerPC EABI specification, GPR r11 is assigned
the dedicated function to point to the previous stack frame.
In the powerpc-specific kernel module loader, do_plt_call()
(in arch/powerpc/kernel/module_32.c), GPR r11 is also used
to generate trampoline code.
This combination crashes the kernel, in the case where the compiler
chooses to use a helper function for saving GPRs on entry, and the
module loader has placed the .init.text section far away from the
.text section, meaning that it has to generate a trampoline for
functions in the .init.text section to call the GPR save helper.
Because the trampoline trashes r11, references to the stack frame
using r11 can cause an oops.
The fix just uses GPR r12 instead of GPR r11 for generating the
trampoline code. According to the statements from Freescale, this is
safe from an EABI perspective.
I've tested the fix for kernel 2.6.33 on MPC8541.
Cc: stable@vger.kernel.org
Signed-off-by: Steffen Rumler <steffen.rumler.ext@nsn.com>
[paulus@samba.org: reworded the description]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cliff Wickman [Thu, 7 Jun 2012 13:31:40 +0000 (08:31 -0500)]
x86/uv: Fix UV2 BAU legacy mode
The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for
tlb-shootdown (selective broadcast mode) always uses UV2
broadcast descriptor format. There is no need to clear the
'legacy' (UV1) mode, because the hardware always uses UV2 mode
for selective broadcast.
But the BIOS uses general broadcast and legacy mode, and the
hardware pays attention to the legacy mode bit for general
broadcast. So the kernel must not clear that mode bit.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Yinghai Lu [Wed, 6 Jun 2012 17:55:40 +0000 (10:55 -0700)]
x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space
Robin found this regression:
| I just tried to boot an 8TB system. It fails very early in boot with:
| Kernel panic - not syncing: Cannot find space for the kernel page tables
git bisect commit
722bc6b16771ed80871e1fd81c86d3627dda2ac8.
A git revert of that commit does boot past that point on the 8TB
configuration.
That commit will add up extra pages for all memory range even
above 4g.
Try to limit that extra page count adding to first entry only.
Bisected-by: Robin Holt <holt@sgi.com>
Tested-by: Robin Holt <holt@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CAE9FiQUj3wyzQxtq9yzBNc9u220p8JZ1FYHG7t%3DMOzJ%3D9BZMYA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Airlie [Fri, 8 Jun 2012 08:42:51 +0000 (09:42 +0100)]
Merge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung into drm-fixes
* 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung:
drm/exynos: fixed blending for hdmi graphic layer
drm/exynos: Remove dummy encoder get_crtc operation implementation
drm/exynos: Keep a reference to frame buffer GEM objects
drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
drm/exynos: fixed size type.
drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}
Dave Airlie [Fri, 8 Jun 2012 08:42:35 +0000 (09:42 +0100)]
Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes
* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
char/agp: add another Ironlake host bridge
drm/i915: fix up ivb plane 3 pageflips
drm/i915: hold forcewake around ring hw init
drm/i915: Mark the ringbuffers as being in the GTT domain
drm/i915/crt: Do not rely upon the HPD presence pin
drm/i915: Reset last_retired_head when resetting ring
Borislav Petkov [Fri, 1 Jun 2012 16:56:00 +0000 (18:56 +0200)]
init: Drop initcall level output
9fb48c744ba6a ("params: add 3rd arg to option handler callback
signature") added similar lines to dmesg:
initlevel:0=early, 4 registered initcalls
initlevel:1=core, 31 registered initcalls
initlevel:2=postcore, 11 registered initcalls
initlevel:3=arch, 7 registered initcalls
initlevel:4=subsys, 40 registered initcalls
initlevel:5=fs, 30 registered initcalls
initlevel:6=device, 250 registered initcalls
initlevel:7=late, 35 registered initcalls
but they don't contain any info for the general user staring at dmesg.
I'm very doubtful the count of initcalls registered per level helps
anyone so drop that output completely.
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell [Fri, 8 Jun 2012 05:28:13 +0000 (14:58 +0930)]
module_param: stop double-calling parameters.
Commit
026cee0086fe1df4cf74691cf273062cc769617d "params:
<level>_initcall-like kernel parameters" set old-style module
parameters to level 0. And we call those level 0 calls where we used
to, early in start_kernel().
We also loop through the initcall levels and call the levelled
module_params before the corresponding initcall. Unfortunately level
0 is early_init(), so we call the standard module_param calls twice.
(Turns out most things don't care, but at least ubi.mtd does).
Change the level to -1 for standard module_param calls.
Reported-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
Paul Mackerras [Fri, 1 Jun 2012 08:13:43 +0000 (18:13 +1000)]
powerpc/time: Sanity check of decrementer expiration is necessary
This reverts
68568add2c ("powerpc/time: Remove unnecessary sanity check
of decrementer expiration"). We do need to check whether we have reached
the expiration time of the next event, because we sometimes get an early
decrementer interrupt, most notably when we set the decrementer to 1 in
arch_irq_work_raise(). The effect of not having the sanity check is that
if timer_interrupt() gets called early, we leave the decrementer set to
its maximum value, which means we then don't get any more decrementer
interrupts for about 4 seconds (or longer, depending on timebase
frequency). I saw these pauses as a consequence of getting a stray
hypervisor decrementer interrupt left over from exiting a KVM guest.
This isn't quite a straight revert because of changes to the surrounding
code, but it restores the same algorithm as was previously used.
Cc: stable@vger.kernel.org
Acked-by: Anton Blanchard <anton@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Linus Torvalds [Fri, 8 Jun 2012 00:54:07 +0000 (17:54 -0700)]
Revert "mm: correctly synchronize rss-counters at exit/exec"
This reverts commit
40af1bbdca47e5c8a2044039bb78ca8fd8b20f94.
It's horribly and utterly broken for at least the following reasons:
- calling sync_mm_rss() from mmput() is fundamentally wrong, because
there's absolutely no reason to believe that the task that does the
mmput() always does it on its own VM. Example: fork, ptrace, /proc -
you name it.
- calling it *after* having done mmdrop() on it is doubly insane, since
the mm struct may well be gone now.
- testing mm against NULL before you call it is insane too, since a
NULL mm there would have caused oopses long before.
.. and those are just the three bugs I found before I decided to give up
looking for me and revert it asap. I should have caught it before I
even took it, but I trusted Andrew too much.
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tao Ma [Thu, 7 Jun 2012 23:04:19 +0000 (19:04 -0400)]
ext4: don't set i_flags in EXT4_IOC_SETFLAGS
Commit
7990696 uses the ext4_{set,clear}_inode_flags() functions to
change the i_flags automatically but fails to remove the error setting
of i_flags. So we still have the problem of trashing state flags.
Fix this by removing the assignment.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Theodore Ts'o [Thu, 7 Jun 2012 22:56:06 +0000 (18:56 -0400)]
ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg
Ext3 filesystems that are converted to use as many ext4 file system
features as possible will enable uninit_bg to speed up e2fsck times.
These file systems will have a native ext3 layout of inode tables and
block allocation bitmaps (as opposed to ext4's flex_bg layout).
Unfortunately, in these cases, when first allocating a block in an
uninitialized block group, ext4 would incorrectly calculate the number
of free blocks in that block group, and then errorneously report that
the file system was corrupt:
EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd
This problem can be reproduced via:
mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g
mount -t ext4 /dev/vdd /mnt
fallocate -l 4600m /mnt/test
The problem was caused by a bone headed mistake in the check to see if a
particular metadata block was part of the block group.
Many thanks to Kees Cook for finding and bisecting the buggy commit
which introduced this bug (commit
fd034a84e1, present since v3.2).
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: stable@kernel.org
Linus Torvalds [Thu, 7 Jun 2012 22:05:43 +0000 (15:05 -0700)]
Merge branch 'akpm' (Andrew's fixups)
Merge random fixes from Andrew Morton.
* emailed from Andrew Morton <akpm@linux-foundation.org>: (11 patches)
mm: correctly synchronize rss-counters at exit/exec
btree: catch NULL value before it does harm
btree: fix tree corruption in btree_get_prev()
ipc: shm: restore MADV_REMOVE functionality on shared memory segments
drivers/platform/x86/acerhdf.c: correct Boris' mail address
c/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignment
c/r: prctl: add ability to get clear_tid_address
c/r: prctl: add minimal address test to PR_SET_MM
c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal
MAINTAINERS: whitespace fixes
shmem: replace_page must flush_dcache and others
Konstantin Khlebnikov [Thu, 7 Jun 2012 21:21:14 +0000 (14:21 -0700)]
mm: correctly synchronize rss-counters at exit/exec
mm->rss_stat counters have per-task delta: task->rss_stat. Before
changing task->mm pointer the kernel must flush this delta with
sync_mm_rss().
do_exit() already calls sync_mm_rss() to flush the rss-counters before
committing the rss statistics into task->signal->maxrss, taskstats,
audit and other stuff. Unfortunately the kernel does this before
calling mm_release(), which can call put_user() for processing
task->clear_child_tid. So at this point we can trigger page-faults and
task->rss_stat becomes non-zero again. As a result mm->rss_stat becomes
inconsistent and check_mm() will print something like this:
| BUG: Bad rss-counter state mm:
ffff88020813c380 idx:1 val:-1
| BUG: Bad rss-counter state mm:
ffff88020813c380 idx:2 val:1
This patch moves sync_mm_rss() into mm_release(), and moves mm_release()
out of do_exit() and calls it earlier. After mm_release() there should
be no pagefaults.
[akpm@linux-foundation.org: tweak comment]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org> [3.4.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joern Engel [Thu, 7 Jun 2012 21:21:14 +0000 (14:21 -0700)]
btree: catch NULL value before it does harm
Storing NULL values in the btree is illegal and can lead to memory
corruption and possible other fun as well. Catch it on insert, instead
of waiting for the inevitable.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>