Commit graph

169175 commits

Author SHA1 Message Date
Xiao Guangrong
5e855db5d8 perf_event: Fix variable initialization in other codepaths
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B20BAA6.7010609@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 17:23:02 +01:00
Ingo Molnar
7931241694 perf kmem: Fix unused argument build warning
Fix:

 builtin-kmem.c: In function 'parse_caller_opt':
 builtin-kmem.c:690: error: unused parameter 'arg'
 builtin-kmem.c: In function 'parse_alloc_opt':
 builtin-kmem.c:697: error: unused parameter 'arg'

Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <4B20A195.8030106@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:44:39 +01:00
Arnaldo Carvalho de Melo
716d69e4fd perf symbols: perf_header__read_build_ids() offset'n'size should be u64
As off_t is a long, so breaking things on 32-bit land. Now
buildids work on 32-bit land.

[root@ana ~]# uname -a
Linux ana.ghostprotocols.net 2.6.31.6-162.fc12.i686 #1 SMP Fri
Dec 4 01:09:09 EST 2009 i686 i686 i386 GNU/Linux [root@ana ~]#
perf buildid-list | tail -5
136ee6792ba2ae57870ecd87369f4ae3194d5b27 /lib/libreadline.so.6.0
d202dcb1ad48d140065783657d37ae3f2d9ab83f /usr/bin/gdb
0a56c0c00dcc2e9e581ae9997f31957c9c4671df
/usr/lib/libdwarf.so.0.0
5f9e6ac95241cbb3227608e0ff2a2e0cbbe72439 /home/acme/bin/perf
925d19eccc2ddb1c9d74dd178a011426f1b124a8 /bin/sleep [root@ana ~]#

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260396578-19116-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:29 +01:00
Arnaldo Carvalho de Melo
8b4825bf8d perf symbols: dsos__read_build_ids() should read both user and kernel buildids
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260396578-19116-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:28 +01:00
Li Zefan
bc3abfb1b5 perf tools: Align long options which have no short forms
Before:

$ ./perf kmem
...
    -l, --line <num>      show n lines
    --raw-ip              show raw ip instead of symbol

After:

$ ./perf kmem
...
    -l, --line <num>      show n lines
        --raw-ip          show raw ip instead of symbol

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <4B20A1A9.3040104@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:28 +01:00
Li Zefan
90b86a9f7d perf kmem: Show usage if no option is specified
As Ingo suggested, make "perf kmem" show help information.
"perf kmem stat [--caller] [--alloc] .." will show memory
statistics.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <4B20A195.8030106@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:27 +01:00
Mike Frysinger
1bbfa6f256 sched: Mark sched_clock() as notrace
The core ftrace code (trace_clock_local) calls sched_clock()
directly, so we don't want to recurisvely trigger the ftrace
code.  Rather than update every sched_clock() definition, tag
the prototype for everyone as notrace.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1260407223-10900-1-git-send-email-vapier@gentoo.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:27 +01:00
Frederic Weisbecker
3786310afe perf sched: Add max delay time snapshot
When we have a maximum latency reported for a task, we need a
convenient way to find the matching location to the raw traces
or to perf sched map that shows where the task has been
eventually scheduled in. This gives a pointer to retrieve the
events that occured during this max latency.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260391208-6808-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:26 +01:00
Julia Lawall
5660ce3424 perf tools: Correct size given to memset
Memset should be given the size of the structure, not the size
of the pointer.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T *x;
expression E;
@@

memset(x, E, sizeof(
+ *
 x))
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <Pine.LNX.4.64.0912092026000.1870@ask.diku.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 08:30:26 +01:00
Xiao Guangrong
21140f4d33 perf_event: Fix perf_swevent_hrtimer() variable initialization
fix:

 [<c0477471>] ? printk+0x1d/0x24
 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280
 [<c0149231>] warn_slowpath_common+0x71/0xd0
 [<c01c98f9>] ? perf_prepare_sample+0x269/0x280
 [<c01492aa>] warn_slowpath_null+0x1a/0x20
 [<c01c98f9>] perf_prepare_sample+0x269/0x280
 [<c016e9f3>] ? cpu_clock+0x53/0x90
 [<c01cc368>] __perf_event_overflow+0x2a8/0x300
 [<c01ccc3b>] perf_event_overflow+0x1b/0x30
 [<c01ccccf>] perf_swevent_hrtimer+0x7f/0x120

This is because 'data.raw' variable not initialize.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B208E93.1010801@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-10 07:11:05 +01:00
Xiao Guangrong
c0c9e72150 perf sched: Fix for getting task's execution time
In current code, task's execute time is got by reading
'/proc/<pid>/sched' file, it's wrong if the task is created
by pthread_create(), because every thread task has same pid.

This way also has two demerits:

 1: 'perf sched replay' can't work if the kernel is not
    compiled with the 'CONFIG_SCHED_DEBUG' option

 2: perf tool should depend on proc file system

So, this patch uses PERF_COUNT_SW_TASK_CLOCK to get task's
execution time instead of reading /proc file.

Changelog v2 -> v3:
use PERF_COUNT_SW_TASK_CLOCK instead of rusage() as Ingo's
suggestion

Reported-by: Torok Edwin <edwintorok@gmail.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Xiao Guangrong <ericxiao.gr@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B1F7322.80103@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 10:59:12 +01:00
Frederic Weisbecker
822a696111 tracing/kprobes: Fix field creation's bad error handling
When we define the common event fields in kprobe, we invert the error
handling and return immediately in case of success. Then we omit
to define specific kprobes fields (ip and nargs), and specific
kretprobes fields (func, ret_ip, nargs). And we only define them
when we fail to create common fields.

The most visible consequence is that we can't create filter for
k(ret)probes specific fields.

This patch re-invert the success/error handling to fix it.

Reported-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1260263815-5167-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 10:32:21 +01:00
Xiao Guangrong
ec89a06fd4 perf_event: Cleanup for cpu_clock_perf_event_update()
Using atomic64_xchg() instead of atomic64_read() and
atomic64_set().

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B1F19DC.90204@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 09:56:27 +01:00
Xiao Guangrong
b93f7978ad perf_event: Allocate children's perf_event_ctxp at the right time
In current code, children task will allocate memory for
'child->perf_event_ctxp' if the parent is counted, we can
do it only if the parent allowed children inherit it.

It can save memory and reduce overhead.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B1F19A8.5040805@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 09:56:27 +01:00
Xiao Guangrong
aa5452d70c perf_event: Clean up __perf_event_init_context()
Clean up the code a bit:

 - define 'perf_cpu_context' variable with 'static'
 - use kzalloc() instead of kmalloc() and memset()

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B1F194D.7080306@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 09:56:27 +01:00
Frederic Weisbecker
44234adcdc hw-breakpoints: Modify breakpoints without unregistering them
Currently, when ptrace needs to modify a breakpoint, like disabling
it, changing its address, type or len, it calls
modify_user_hw_breakpoint(). This latter will perform the heavy and
racy task of unregistering the old breakpoint and registering a new
one.

This is racy as someone else might steal the reserved breakpoint
slot under us, which is undesired as the breakpoint is only
supposed to be modified, sometimes in the middle of a debugging
workflow. We don't want our slot to be stolen in the middle.

So instead of unregistering/registering the breakpoint, just
disable it while we modify its breakpoint fields and re-enable it
after if necessary.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1260347148-5519-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 09:48:20 +01:00
Masami Hiramatsu
c937fe20cb perf probe: Update perf-probe document
Add --list and --del option descriptions to perf-probe.txt.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091208220330.10142.73296.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:54 +01:00
Masami Hiramatsu
fa28244d12 perf probe: Support --del option
Support perf probe --del <event> option. Currently,
perf probe can have only one event for each --del option.
If you'd like to delete several probe events, you need
to specify --del for each events.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220323.10142.62079.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:53 +01:00
Masami Hiramatsu
a7c312bed7 trace-kprobe: Support delete probe syntax
Support delete probe syntax. The syntax is "-:[group/]event".

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220316.10142.39192.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
2009-12-09 07:26:53 +01:00
Masami Hiramatsu
f984f03da3 perf probe: Support vmlinux on cwd by default
Support vmlinux on current working direcotry by default and
also update file-open messages.
Now perf probe searches ./vmlinux too.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220309.10142.33040.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:52 +01:00
Masami Hiramatsu
17f88fcd66 perf probe: Remove event suffix number _0
Remove event suffix number _0 if it is the first.
The first event has no suffix, and from the second,
each event has suffix number counted from _1. This
reduces typing cost :-).

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220301.10142.50031.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:52 +01:00
Masami Hiramatsu
d1bde3f755 perf probe: Fix add-probe command syntax without --add option
Fix add-probe command syntax without --add option.
perf-probe supports add-probe command without --add
option. But it treats each argument as an event definition.
e.g.

perf probe func arg1 arg2

 is interpreted as

perf probe --add func --add arg1 --add arg2

But it may be useless in many cases.

This patch fixes this syntax to fold those arguments into
one event definition if there is no --add option. With this
change, above command is interpreted as below;

perf probe --add "func arg1 arg2"

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220254.10142.73767.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:51 +01:00
Masami Hiramatsu
a9b495b0d3 perf probe: Change probe-added message more user-friendly
Change probe-added message more user-friendly expression and
show usage of new events.

Before:
Added new event: p:probe/schedule_0 schedule+10 prev=%ax cpu=%bx

After:
Added new event:
  probe:schedule_1                         (on schedule+1 with prev cpu)

You can now use it on all perf tools, such as:

        perf record -e probe:schedule_1 -a sleep 1

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220247.10142.91642.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:51 +01:00
Masami Hiramatsu
278498d438 perf probe: Change event list format
Change event list format for user readability. perf probe --list
shows event list in "[GROUP:EVENT] EVENT-DEFINITION" format, but
this format is different from the output of perf-list, and
EVENT-DEFINITION is a bit blunt. This patch changes the format to
more user friendly one.

Before:
[probe:schedule_0]	schedule+10 prev cpu

After:
  probe:schedule_0                         (on schedule+10 with prev cpu)

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091208220240.10142.42916.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 07:26:50 +01:00
Stephen Rothwell
6ab8886326 perf: hw_breakpoints: Fix percpu namespace clash
Today's linux-next build failed with:

  kernel/hw_breakpoint.c:86: error: 'task_bp_pinned' redeclared as different kind of symbol
  ...

Caused by commit dd17c8f729 ("percpu:
remove per_cpu__ prefix") from the percpu tree interacting with
commit 56053170ea ("hw-breakpoints:
Fix task-bound breakpoint slot allocation") from the tip tree.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20091208182515.bb6dda4a.sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-08 09:34:43 +01:00
Arnd Bergmann
2ff6cfd707 perf events: hw_breakpoints: Don't include asm/hw_breakpoint.h in user space
asm/hw_breakpoint.h is evidently a kernel internal file and
should not be included globally, not even under an #ifdef.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <200912071712.58650.arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-08 02:58:40 +01:00
Masami Hiramatsu
d3a2dbf844 perf probe: Use pr_debug for debug message
Use pr_debug() for "missing vmlinux" debugging message.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170059.19230.51459.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 18:33:22 +01:00
Masami Hiramatsu
849884508e perf probe: Check e_snprintf() format string
Check e_snprintf() format string by gcc, and fix a bug of
e_snprintf() caller.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170053.19230.7690.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 18:33:21 +01:00
Masami Hiramatsu
e1d2017b24 perf probe: Fix event namelist to duplicate string
Fix event namelist to duplicate string. Without duplicating, adding
multiple probes causes stack overwrite bug, because it reuses a
buffer on stack while the buffer is already added in the namelist.
String duplication solves this bug because only contents of the
buffer is copied to the namelist.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170046.19230.55557.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 18:33:21 +01:00
Juha Leppanen
d56728b8d7 perf probe: Fix strtailcmp() to compare s1and s2[0]
Fix strtailcmp() to compare s1[0] and s2[0]. strtailcmp() returns 0
if "a" and "b" or "a" and "ab", it's a wrong behavior. This patch
fixes it.

Signed-off-by: "Juha Leppanen" <juha_motorsportcom@luukku.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Juha Leppanen <juha_motorsportcom@luukku.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170040.19230.37464.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 18:33:20 +01:00
Masami Hiramatsu
d32ba45503 x86 insn: Delete empty or incomplete inat-tables.c
Delete empty or incomplete inat-tables.c if gen-insn-attr-x86.awk
failed, because it causes a build error if user tries to build
kernel next time.

Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091207170033.19230.37688.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 18:33:19 +01:00
OGAWA Hirofumi
cbe5c34c8c x86: Compile insn.c and inat.c only for KPROBES
At least, insn.c and inat.c is needed for kprobe for now. So,
this compile those only if KPROBES is enabled.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <878wdg8icq.fsf@devron.myhome.or.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 08:31:28 +01:00
Ulrich Drepper
180570fdb7 perf tools: Optimize parse_subsystem_tracepoint_event()
Uses of strcat are almost always signs that someone is too lazy
to think about the code a bit more carefully.  One always has to
know about the lengths of the strings involved to avoid buffer
overflows.

This is one case where the size of the object code for me is
reduced by 38 bytes.  The code should also be faster, especially
if flags is non-NULL.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Cc: a.p.zijlstra@chello.nl
Cc: fweisbec@gmail.com
Cc: jaswinderrajput@gmail.com
Cc: paulus@samba.org
LKML-Reference: <200912061825.nB6IPUa1023306@hs20-bc2-1.build.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 08:09:29 +01:00
Tom Zanussi
67a6259ec9 perf trace/scripting: Don't display 'scripting unsupported' msg unnecessarily
The 'scripting unsupported' message should only be displayed
when the -s or -g options are used, and not when they aren't, as
the current code does.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: rostedt@goodmis.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1260163919-6679-3-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 08:05:07 +01:00
Ingo Molnar
11a80ddbf3 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2009-12-07 08:03:35 +01:00
Frederic Weisbecker
56053170ea hw-breakpoints: Fix task-bound breakpoint slot allocation
Whatever the context nature of a breakpoint, we always perform the
following constraint checks before allocating it a slot:

- Check the number of pinned breakpoint bound the concerned cpus
- Check the max number of task-bound breakpoints that are belonging
  to a task.
- Add both and see if we have a reamining slot for the new breakpoint

This is the right thing to do when we are about to register a cpu-only
bound breakpoint. But not if we are dealing with a task bound
breakpoint. What we want in this case is:

- Check the number of pinned breakpoint bound the concerned cpus
- Check the number of breakpoints that already belong to the task
  in which the breakpoint to register is bound to.
- Add both

This fixes a regression that makes the "firefox -g" command fail to
register breakpoints once we deal with a secondary thread.

Reported-by: Walt <w41ter@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
2009-12-07 07:05:28 +01:00
Frederic Weisbecker
ed872d09ef hw-breakpoints: Zeroe the breakpoint attrs on initialization
The perf attrs used to set up breakpoint parameters are often allocated
in the stack and not zeroed out before calling hw_breakpoint_init().
Handle it from this helper to avoid random attributes set by the stack.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
2009-12-07 07:04:33 +01:00
Tom Zanussi
3a9a0beba2 perf trace/scripting: Fix compile error when libperl not installed
When I added the xs callbacks into perf, I forgot to re-check
the no-libperl case. This patch fixes the undefined reference
error for that.

Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260153712.6564.4.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 06:31:37 +01:00
Xiao Guangrong
f48f669d42 perf_event: Eliminate raw->size
raw->size is not used, this patch just cleans it up.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B1C8CC4.4050007@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 06:26:25 +01:00
Xiao Guangrong
d9541ed324 perf_event: Fix __dsos__write_buildid_table()
The remain buff size is 'len - pos->long_name_len - 1', not
'len - pos->long_name_len + 1'

This bug was introduced by commit 7691b1e ("perf tools: Misc small
fixes").

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B1C7F73.80707@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 06:26:24 +01:00
Xiao Guangrong
d8bd9e0aed perf_event: Fix raw event processing
We use 'data.raw_data' parameter to call process_raw_event(),
but data.raw_data buffer not include data size. it can make perf
tool crash.

This bug was introduced by commit 180f95e29a ("perf: Make common
SAMPLE_EVENT parser").

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B1C7F45.5080105@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 06:26:24 +01:00
Xiao Guangrong
c0777c5aa8 perf/sched: Fix 'perf sched trace'
If we use 'perf sched trace', it will call symbol__init() again,
and can lead to a perf tool crash:

 [root@localhost perf]# ./perf sched trace
 *** glibc detected *** ./perf: free(): invalid next size (normal): 0x094c1898 ***
 ======= Backtrace: =========
 /lib/libc.so.6[0xb7602404]
 /lib/libc.so.6(cfree+0x96)[0xb76043b6]
 ./perf[0x80730fe]
 ./perf[0x8074c97]
 ./perf[0x805eb59]
 ./perf[0x80536fd]
 ./perf[0x804b618]
 ./perf[0x804bdc3]
 /lib/libc.so.6(__libc_start_main+0xe5)[0xb75a9735]
 ./perf[0x804af81]
 ======= Memory map: ========
 08048000-08158000 r-xp 00000000 fe:00 556831     /home/eric/....
 08158000-08168000 rw-p 0010f000 fe:00 556831     /home/eric/...
 08168000-085fe000 rw-p 00000000 00:00 0
 094ab000-094cc000 rw-p 00000000 00:00 0          [heap]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
LKML-Reference: <4B1C7EE1.8030906@cn.fujitsu.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-07 06:26:22 +01:00
Arnaldo Carvalho de Melo
b9b1e1c71a perf buildid-list: Fix copy'n'paste help message
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260129790-11520-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 21:07:08 +01:00
OGAWA Hirofumi
7691b1ec2e perf tools: Misc small fixes
- util/header.c
	"len" is aligned to 64. So, it tries to write the out of
	long_name buffer.

	So, this use "zero_buf" to write aligned area.

- util/trace-event-read.c
	"size" is not including nul byte. So, this allocates it, and set '\0'.

- util/trace-event-parse.c
	It needs parens to calc correct size.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <87d42s8iiu.fsf_-_@devron.myhome.or.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 18:15:02 +01:00
OGAWA Hirofumi
180f95e29a perf: Make common SAMPLE_EVENT parser
Currently, sample event data is parsed for each commands, and it
is assuming that the data is not including other data. (E.g.
timechart, trace, etc. can't parse the event if it has
PERF_SAMPLE_CALLCHAIN)

So, even if we record the superset data for multiple commands at
a time, commands can't parse. etc.

To fix it, this makes common sample event parser, and use it to
parse sample event correctly. (PERF_SAMPLE_READ is unsupported
for now though, it seems to be not using.)

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <87hbs48imv.fsf@devron.myhome.or.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 18:15:01 +01:00
OGAWA Hirofumi
028c515253 perf timechart: Fix header handling
Update "struct trace_entry" to match with current one. And
remove "size" field from it.

If it has "size", it become cause of alignment mismatch of
structure with kernel.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Arjan van de Ven <arjan@infradead.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <87ljhg8ioe.fsf@devron.myhome.or.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 18:15:01 +01:00
Jean Delvare
be2bf0a2df x86, perf probe: Fix warning in test_get_len()
Fix the following warning:

 arch/x86/tools/test_get_len.c: In function "main":
 arch/x86/tools/test_get_len.c:116: warning: unused variable "c"

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 12:53:40 +01:00
Julia Lawall
59b4caeb79 perf tools: Correct size computation in tracepoint_id_to_path()
The size argument to zalloc should be the size of desired
structure, not the pointer to it.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@expression@
expression *x;
@@

x =
 <+...
-sizeof(x)
+sizeof(*x)
...+>// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <Pine.LNX.4.64.0912061016120.20858@ask.diku.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-06 10:21:59 +01:00
Frederic Weisbecker
af2d8289f5 x86: Fixup wrong irq frame link in stacktraces
When we enter in irq, two things can happen to preserve the link
to the previous frame pointer:

- If we were in an irq already, we don't switch to the irq stack
  as we are inside. We just need to save the previous frame
  pointer and to link the new one to the previous.

- Otherwise we need another level of indirection. We enter the irq with
  the previous stack. We save the previous bp inside and make bp
  pointing to its saved address. Then we switch to the irq stack and
  push bp another time but to the new stack. This makes two levels to
  dereference instead of one.

In the second case, the current stacktrace code omits the second level
and loses the frame pointer accuracy. The stack that follows will then
be considered as unreliable.

Handling that makes the perf callchain happier.
Before:

43.94%  [k] _raw_read_lock
            |
            --- _read_lock
               |
               |--60.53%-- send_sigio
               |          __kill_fasync
               |          kill_fasync
               |          evdev_pass_event
               |          evdev_event
               |          input_pass_event
               |          input_handle_event
               |          input_event
               |          synaptics_process_byte
               |          psmouse_handle_byte
               |          psmouse_interrupt
               |          serio_interrupt
               |          i8042_interrupt
               |          handle_IRQ_event
               |          handle_edge_irq
               |          handle_irq
               |          __irqentry_text_start
               |          ret_from_intr
               |          |
               |          |--30.43%-- __select
               |          |
               |          |--17.39%-- 0x454f15
               |          |
               |          |--13.04%-- __read
               |          |
               |          |--13.04%-- vread_hpet
               |          |
               |          |--13.04%-- _xcb_lock_io
               |          |
               |           --13.04%-- 0x7f630878ce8

After:

    50.00%  [k] _raw_read_lock
            |
            --- _read_lock
               |
               |--98.97%-- send_sigio
               |          __kill_fasync
               |          kill_fasync
               |          evdev_pass_event
               |          evdev_event
               |          input_pass_event
               |          input_handle_event
               |          input_event
               |          |
               |          |--96.88%-- synaptics_process_byte
               |          |          psmouse_handle_byte
               |          |          psmouse_interrupt
               |          |          serio_interrupt
               |          |          i8042_interrupt
               |          |          handle_IRQ_event
               |          |          handle_edge_irq
               |          |          handle_irq
               |          |          __irqentry_text_start
               |          |          ret_from_intr
               |          |          |
               |          |          |--39.78%-- __const_udelay
               |          |          |          |
               |          |          |          |--91.89%-- ath5k_hw_register_timeout
               |          |          |          |          ath5k_hw_noise_floor_calibration
               |          |          |          |          ath5k_hw_reset
               |          |          |          |          ath5k_reset
               |          |          |          |          ath5k_config
               |          |          |          |          ieee80211_hw_config
               |          |          |          |          |
               |          |          |          |          |--88.24%-- ieee80211_scan_work
               |          |          |          |          |          worker_thread
               |          |          |          |          |          kthread
               |          |          |          |          |          child_rip
               |          |          |          |          |
               |          |          |          |           --11.76%-- ieee80211_scan_completed
               |          |          |          |                     ieee80211_scan_work
               |          |          |          |                     worker_thread
               |          |          |          |                     kthread
               |          |          |          |                     child_rip
               |          |          |          |
               |          |          |           --8.11%-- ath5k_hw_noise_floor_calibration
               |          |          |                     ath5k_hw_reset
               |          |          |                     ath5k_reset
               |          |          |                     ath5k_config

Note: This does not only affect perf events but also x86-64
stacktraces. They were considered as unreliable once we quit
the irq stack frame.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2009-12-06 08:27:24 +01:00
Frederic Weisbecker
b625b3b3b7 x86: Fixup wrong debug exception frame link in stacktraces
While dumping a stacktrace, the end of the exception stack won't link
the frame pointer to the previous stack.

The interrupted stack will then be considered as unreliable and ignored
by perf, as the frame pointer is unreliable itself.

This happens because we overwrite the frame pointer that links to the
interrupted frame with the address of the exception stack. This is
done in order to reserve space inside.
But rbp has been chosen here only because it is not a scratch register,
so that the address of the exception stack remains in rbp after calling
do_debug(), we can then release the exception stack space without the
need to retrieve its address again.

But we can pick another non-scratch register to do that, so that we
preserve the link to the interrupted stack frame in the stacktraces.

Just randomly choose r12. Every registers are saved just before and
restored just after calling do_debug(). And r12 is not used in the
middle, which makes it a perfect candidate.

Example: perf record -g -a -c 1 -f -e mem:$(tasklist_lock_addr):rw

Before:
    44.18%  [k] _raw_read_lock
            |
            |
            ---  |--6.31%-- waitid
                 |
                 |--4.26%-- writev
                 |
                 |--3.63%-- __select
                 |
                 |--3.15%-- __waitpid
                 |          |
                 |          |--28.57%-- 0x8b52e00000139f
                 |          |
                 |          |--28.57%-- 0x8b52e0000013c6
                 |          |
                 |          |--14.29%-- 0x7fde786dc000
                 |          |
                 |          |--14.29%-- 0x62696c2f7273752f
                 |          |
                 |           --14.29%-- 0x1ea9df800000000
                 |
                 |--3.00%-- __poll

After:

    43.94%  [k] _raw_read_lock
            |
            --- _read_lock
               |
               |--60.53%-- send_sigio
               |          __kill_fasync
               |          kill_fasync
               |          evdev_pass_event
               |          evdev_event
               |          input_pass_event
               |          input_handle_event
               |          input_event
               |          synaptics_process_byte
               |          psmouse_handle_byte
               |          psmouse_interrupt
               |          serio_interrupt
               |          i8042_interrupt
               |          handle_IRQ_event
               |          handle_edge_irq
               |          handle_irq
               |          __irqentry_text_start
               |          ret_from_intr
               |          |
               |          |--30.43%-- __select
               |          |
               |          |--17.39%-- 0x454f15
               |          |
               |          |--13.04%-- __read
               |          |
               |          |--13.04%-- vread_hpet
               |          |
               |          |--13.04%-- _xcb_lock_io
               |          |
               |           --13.04%-- 0x7f630878ce87

Note: it does not only affect perf events but also other stacktraces in
x86-64. They were considered as unreliable once we quit the debug
stack frame.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2009-12-06 08:27:22 +01:00