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Commit Graph

168997 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
2890284bcf perf tools: Move graph_line and graph_dotted_line from top
So that they can be used in other tools.

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: <1259005869-13487-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 21:55:20 +01:00
Arnaldo Carvalho de Melo
cc612d8199 perf symbols: Look for vmlinux in more places
Now that we can check the buildid to see if it really matches,
this can be done safely:

  vmlinux
  /boot/vmlinux
  /boot/vmlinux-<uts.release>
  /lib/modules/<uts.release>/build/vmlinux
  /usr/lib/debug/lib/modules/%s/vmlinux

More can be added - if you know about distros that put the
vmlinux somewhere else please let us know.

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: <1259001550-8194-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 19:51:48 +01:00
Frederic Weisbecker
1b290d670f perf tools: Add support for breakpoint events in perf tools
Add the breakpoint events support with this new sysnopsis:

  mem:addr[:access]

Where addr is a raw addr value in the kernel and access can be
either [r][w][x]

Example to profile tasklist_lock:

	$ grep tasklist_lock /proc/kallsyms
	ffffffff8189c000 D tasklist_lock

	$ perf record -e mem:0xffffffff8189c000:rw -a -f -c 1
	$ perf report

	# Samples: 62
	#
	# Overhead          Command  Shared Object  Symbol
	# ........  ...............  .............  ......
	#
	    29.03%          swapper  [kernel]       [k] _raw_read_trylock
	    29.03%          swapper  [kernel]       [k] _raw_read_unlock
	    19.35%             init  [kernel]       [k] _raw_read_trylock
	    19.35%             init  [kernel]       [k] _raw_read_unlock
	     1.61%         events/0  [kernel]       [k] _raw_read_trylock
	     1.61%         events/0  [kernel]       [k] _raw_read_unlock

Coming soon:

 - Support for symbols in the event definition.

 - Default period to 1 for breakpoint events because these are
   not high frequency events. The same thing is needed for trace
   events.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258987355-8751-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
2009-11-23 18:18:31 +01:00
Frederic Weisbecker
f5ffe02e50 perf: Add kernel side syscall events support for breakpoints
Add the remaining necessary bits to support breakpoints created
through perf syscall.

We don't use the software counter interface as:

- We don't need to check against recursion, this is already done
  in hardware breakpoints arch level.

- We already know the perf event we are dealing with when the
  event is to be committed.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258987355-8751-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 18:18:31 +01:00
Frederic Weisbecker
fdf6bc9522 hw-breakpoints: Check the breakpoint params from perf tools
Perf tools create perf events as disabled in the beginning.
Breakpoints are then considered like ptrace temporary
breakpoints, only meant to reserve a breakpoint slot until we
get all the necessary informations from the user.

In this case, we don't check the address that is breakpointed as
it is NULL in the ptrace case.

But perf tools don't have the same purpose, events are created
disabled to wait for all events to be created before enabling
all of them. We want to check the breakpoint parameters in this
case.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258987355-8751-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 18:18:30 +01:00
Frederic Weisbecker
e6db487657 hw-breakpoints: Include only linux/perf_event.h from kernel part of bp headers
As userspace only needs the breakpoints enum types from the
breakpoints headers.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258987355-8751-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 18:18:30 +01:00
K.Prasad
ba6909b719 hw-breakpoint: Attribute authorship of hw-breakpoint related files
Attribute authorship to developers of hw-breakpoint related
files.

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123154713.GA5593@in.ibm.com>
[ v2: moved it to latest -tip ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 18:18:29 +01:00
Peter Zijlstra
acd1d7c1f8 perf_events: Restore sanity to scaling land
It is quite possible to call update_event_times() on a context
that isn't actually running and thereby confuse the thing.

perf stat was reporting !100% scale values for software counters
(2e2af50b perf_events: Disable events when we detach them,
solved the worst of that, but there was still some left).

The thing that happens is that because we are not self-reaping
(we have a caring parent) there is a time between the last
schedule (out) and having do_exit() called which will detach the
events.

This period would be accounted as enabled,!running because the
event->state==INACTIVE, even though !event->ctx->is_active.

Similar issues could have been observed by calling read() on a
event while the attached task was not scheduled in.

Solve this by teaching update_event_times() about
ctx->is_active.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1258984836.4531.480.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 15:22:19 +01:00
Peter Zijlstra
4ed7c92d68 perf_events: Undo some recursion damage
Make perf_swevent_get_recursion_context return a context number
and disable preemption.

This could be used to remove the IRQ disable from the trace bit
and index the per-cpu buffer with.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091123103819.993226816@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:57 +01:00
Peter Zijlstra
f67218c3e9 perf_events: Fix __perf_event_exit_task() vs. update_event_times() locking
Move the update_event_times() call in __perf_event_exit_task()
into list_del_event() because that holds the proper lock
(ctx->lock) and seems a more natural place to do the last time
update.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123103819.842455480@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:57 +01:00
Peter Zijlstra
5e942bb333 perf_events: Update the context time on exit
It appeared we did call update_event_times() on exit, but we
failed to update the context time, which renders the former
moot.

Locking is a bit iffy, we call update_event_times under
ctx->mutex instead of ctx->lock - the next patch fixes this.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123103819.764207355@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:56 +01:00
Peter Zijlstra
2e2af50b1f perf_events: Disable events when we detach them
If we leave the event in STATE_INACTIVE, any read of the event
after the detach will increase the running count but not the
enabled count and cause funny scaling artefacts.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123103819.689055515@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:56 +01:00
Peter Zijlstra
6c2bfcbe58 perf_events: Fix style nits
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123103819.613427378@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:55 +01:00
Peter Zijlstra
a66a3052e2 perf_events: Undo copy/paste damage
We had two almost identical functions, avoid the duplication.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091123103819.537537928@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:49:55 +01:00
Ingo Molnar
a4234bfcf4 perf_events: Optimize the swcounter hotpath
The structure init creates a bit memcpy, which shows
up big time in perf annotate output:

          :      ffffffff810a859d <__perf_sw_event>:
     1.68 :      ffffffff810a859d:       55                      push   %rbp
     1.69 :      ffffffff810a859e:       41 89 fa                mov    %edi,%r10d
     0.01 :      ffffffff810a85a1:       49 89 c9                mov    %rcx,%r9
     0.00 :      ffffffff810a85a4:       31 c0                   xor    %eax,%eax
     1.71 :      ffffffff810a85a6:       b9 16 00 00 00          mov    $0x16,%ecx
     0.00 :      ffffffff810a85ab:       48 89 e5                mov    %rsp,%rbp
     0.00 :      ffffffff810a85ae:       48 83 ec 60             sub    $0x60,%rsp
     1.52 :      ffffffff810a85b2:       48 8d 7d a0             lea    -0x60(%rbp),%rdi
    85.20 :      ffffffff810a85b6:       f3 ab                   rep stos %eax,%es:(%rdi)

None of the callees depends on the structure being pre-initialized,
so only initialize ->addr. This gets rid of the memcpy overhead.

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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 11:48:27 +01:00
Ingo Molnar
6e3d8330ae perf events: Do not generate function trace entries in perf code
Decreases perf overhead when function tracing is enabled,
by about 50%.

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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 10:19:20 +01:00
Simon Kaempflein
bfd451184d perf record, x86: Print more intelligent error message when sampling fails
Print more accurate error message when "perf record" fails because
there is no APIC support, on x86.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 09:40:13 +01:00
Michael S. Tsirkin
81516c5fc8 perf: Use default compiler mode by default
gcc with no flags typically is a sane default for systems to
use, and looking at the running kernel is probably broken for
cross-builds anyway, so let's not do this.  Add EXTRA_CFLAGS so
that users can override default gcc mode if they want to.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arjan van de Ven <arjan@infradead.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091122121335.GA24254@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-23 07:55:57 +01:00
Arnaldo Carvalho de Melo
50e5095afa perf report: Do map lookups in resolve_callchain()
Bug introduced in 439d473b47,
making the initial map be used for all IPs, so that symbols
outside this initial map would either be erroneously resolved or
not resolve at all.

Reported-by: Ingo Molnar <mingo@elte.hu>
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: <1258909162-28496-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 18:54:24 +01:00
Arnaldo Carvalho de Melo
87f8ea4cd3 perf symbols: Show messages about module loading only if verbose >= 1
Suggested-by: Ingo Molnar <mingo@elte.hu>
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: <1258903301-20584-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 18:54:24 +01:00
Michael S. Tsirkin
b197c7ef71 perf tools: Suggest static libraries as well
On error, suggest installing static libraries
along with shared libraries.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091122131311.GA24318@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 14:26:06 +01:00
Michael S. Tsirkin
7baed9af4b perf tools: Add V=2 option to help debug config issues
Make standard error show up on console when V=2 is set.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091122112726.GC13644@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 13:05:12 +01:00
Ingo Molnar
645e8cc0c9 perf_events: Fix modular build
Fix:

  ERROR: "perf_swevent_put_recursion_context" [fs/ext4/ext4.ko] undefined!
  ERROR: "perf_swevent_get_recursion_context" [fs/ext4/ext4.ko] undefined!

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1258864015-10579-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 12:21:33 +01:00
Pekka Enberg
e57cfcdac6 perf symbols: Fix ELF header errors during "perf kmem record"
The write_event() function in builtin-record.c writes out all
mmap()'d DSOs including non-ELF files like GNOME resource files
and such.

Therefore, check for ELF_K_ELF in filename__read_build_id()
before attempting to read the ELF header with gelf_getehdr().

Fixes the following error messages when running "perf kmem
record":

  penberg@penberg-laptop:~/src/linux/tools/perf$ perf kmem record
  ^C[ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.753 MB perf.data (~32885 samples) ]
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.
  filename__read_build_id: cannot get elf header.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1258885784-11709-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 12:19:07 +01:00
Pekka Enberg
f3ced7cdb2 perf kmem: Add --sort hit and --sort frag
This patch adds support for "--sort hit" and "--sort frag" to
the "perf kmem" tool. The former was already mentioned in the
help text and the latter is useful for finding call-sites that
exhibit worst case behavior for SLAB allocators.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: linux-mm@kvack.org <linux-mm@kvack.org>
LKML-Reference: <1258883880-7149-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 11:21:37 +01:00
Márton Németh
96b02d78a7 perf_event: Remove redundant zero fill
The buffer is first zeroed out by memset(). Then strncpy() is
used to fill the content. The strncpy() function also pads the
string till the end of the specified length, which is redundant.
The strncpy() does not ensures that the string will be properly
closed with 0. Use strlcpy() instead.

The semantic match that finds this kind of pattern is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression buffer;
expression size;
expression str;
@@
	memset(buffer, 0, size);
	...
-	strncpy(
+	strlcpy(
	buffer, str, sizeof(buffer)
	);
@@
expression buffer;
expression size;
expression str;
@@
	memset(&buffer, 0, size);
	...
-	strncpy(
+	strlcpy(
	&buffer, str, sizeof(buffer));
@@
expression buffer;
identifier field;
expression size;
expression str;
@@
	memset(buffer, 0, size);
	...
-	strncpy(
+	strlcpy(
	buffer->field, str, sizeof(buffer->field)
	);
@@
expression buffer;
identifier field;
expression size;
expression str;
@@
	memset(&buffer, 0, size);
	...
-	strncpy(
+	strlcpy(
	buffer.field, str, sizeof(buffer.field));
// </smpl>

On strncpy() vs strlcpy() see
http://www.gratisoft.us/todd/papers/strlcpy.html .

Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4B086547.5040100@freemail.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 09:49:26 +01:00
Frederic Weisbecker
5093ebad5f hw-breakpoints: Separate the kernel part from breakpoint headers
So that we can include this header from userspace tools, like
perf tools, to get the breakpoint types and len definitions.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258863695-10464-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 09:03:43 +01:00
Frederic Weisbecker
b3a75542d3 hw-breakpoints: Remove x86 specific headers from core file
Remove asm/processor.h and asm/debugreg.h as these headers are
not used anymore in the hw-breakpoints core file.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258863695-10464-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 09:03:43 +01:00
Frederic Weisbecker
28889bf9e2 tracing: Forget about the NMI buffer for syscall events
We are never in an NMI context when we commit a syscall trace to
perf. So just forget about the nmi buffer there.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1258863695-10464-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 09:03:42 +01:00
Frederic Weisbecker
ce71b9df88 tracing: Use the perf recursion protection from trace event
When we commit a trace to perf, we first check if we are
recursing in the same buffer so that we don't mess-up the buffer
with a recursing trace. But later on, we do the same check from
perf to avoid commit recursion. The recursion check is desired
early before we touch the buffer but we want to do this check
only once.

Then export the recursion protection from perf and use it from
the trace events before submitting a trace.

v2: Put appropriate Reported-by tag

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1258864015-10579-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-22 09:03:42 +01:00
Arnaldo Carvalho de Melo
e25613683b perf trace: Read_tracing_data should die() another day
It better propagate errors, also if we do a simple:

[root@doppio linux-2.6-tip]# perf record -R -a -f sleep 3s ;
perf trace [ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.182 MB perf.data (~7972 samples) ]
Fatal: not an trace data file
[root@doppio linux-2.6-tip]#

That is what is expected, right? I.e. as we didn't specify any
tracepoint event via -e, it should gracefully bail out and not
SEGFAULT.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
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: <1258821086-11521-3-git-send-email-acme@infradead.org>
[ Fixed the error messages some more ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 17:45:59 +01:00
Arnaldo Carvalho de Melo
c12e15e71d perf symbols: Old versions of elf.h don't have NT_GNU_BUILD_ID
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: <1258821086-11521-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 17:45:59 +01:00
Arnaldo Carvalho de Melo
90c83218c3 perf symbols: Fixup kernel_maps__fixup_end end map
We better call this routine after both the kernel and modules
are loaded, because as it was if there weren't modules it would not
be called, resulting in kernel_map->end remaining at zero, so no
map would be found and consequently the kernel symtab wouldn't
get loaded, i.e. no kernel symbols would be resolved.

Also this fixes another case, that is when we _have_ modules,
but the last map would have its ->end address not set before we
loaded its symbols, which would never happen because ->end was
not set.

Reported-by: Ingo Molnar <mingo@elte.hu>
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: <1258821086-11521-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 17:45:58 +01:00
Stephane Eranian
8904b18046 perf_events: Fix default watermark calculation
This patch fixes the default watermark value for the sampling
buffer. With the existing calculation (watermark =
max(PAGE_SIZE, max_size / 2)), no notification was ever received
when the buffer was exactly 1 page. This was because you would
never cross the threshold (there is no partial samples).

In certain configuration, there was no possibilty detecting the
problem because there was not enough space left to store the
LOST record.In fact, there may be a more generic problem here.
The kernel should ensure that there is alaways enough space to
store one LOST record.

This patch sets the default watermark to half the buffer size.
With such limit, we are guaranteed to get a notification even
with a single page buffer assuming no sample is bigger than a
page.

Signed-off-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212509.344964101@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1256302576-6169-1-git-send-email-eranian@gmail.com>
2009-11-21 14:11:41 +01:00
Peter Zijlstra
6f10581aea perf: Fix locking for PERF_FORMAT_GROUP
We should hold event->child_mutex when iterating the inherited
counters, we should hold ctx->mutex when iterating siblings.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212509.251030114@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:40 +01:00
Peter Zijlstra
59ed446f79 perf: Fix event scaling for inherited counters
Properly account the full hierarchy of counters for both the
count (we already did so) and the scale times (new).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212509.153379276@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:40 +01:00
Peter Zijlstra
2b8988c9f7 perf: Fix time locking
Most sites updating ctx->time and event times do so under
ctx->lock, make sure they all do.

This was made possible by removing the __perf_event_read() call
from __perf_event_sync_stat(), which already had this lock
taken.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212509.102316434@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:39 +01:00
Peter Zijlstra
58e5ad1de3 perf: Simplify __perf_event_read
cpuctx is always active, task context is always active for
current

the previous condition verifies that if its a task context its
for current, hence we can assume ctx->is_active.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212509.000272254@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:39 +01:00
Peter Zijlstra
3dbebf15c5 perf: Simplify __perf_event_sync_stat
Removes constraints from __perf_event_read() by leaving it with
a single callsite; this callsite had ctx->lock held, the other
one does not.

Removes some superfluous code from __perf_event_sync_stat().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.918544317@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:39 +01:00
Peter Zijlstra
f6f8378522 perf: Optimize __perf_event_read()
Both callers actually have IRQs disabled, no need doing so
again.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.863685796@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:38 +01:00
Peter Zijlstra
02ffdbc866 perf: Optimize perf_event_task_sched_out
Remove an update_context_time() call from the
perf_event_task_sched_out() path and into the branch its needed.

The call was both superfluous, because __perf_event_sched_out()
already does it, and wrong, because it was done without holding
ctx->lock.

Place it in perf_event_sync_stat(), which is the only place it
is needed and which does already hold ctx->lock.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.779516394@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:38 +01:00
Peter Zijlstra
abf4868b85 perf: Fix PERF_FORMAT_GROUP scale info
As Corey reported, the total_enabled and total_running times
could occasionally be 0, even though there were events counted.

It turns out this is because we record the times before reading
the counter while the latter updates the times.

This patch corrects that.

While looking at this code I found that there is a lot of
locking iffyness around, the following patches correct most of
that.

Reported-by: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.685559857@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:37 +01:00
Peter Zijlstra
f6d9dd237d perf: Optimize perf_event_mmap_ctx()
Remove a rcu_read_{,un}lock() pair and a few conditionals.

We can remove the rcu_read_lock() by increasing the scope of one
in the calling function.

We can do away with the system_state check if the machine still
boots after this patch (seems to be the case).

We can do away with the list_empty() check because the bare
list_for_each_entry_rcu() reduces to that now that we've removed
everything else.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.606459548@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:37 +01:00
Peter Zijlstra
f6595f3a96 perf: Optimize perf_event_comm_ctx()
Remove a rcu_read_{,un}lock() pair and a few conditionals.

We can remove the rcu_read_lock() by increasing the scope of one
in the calling function.

We can do away with the system_state check if the machine still
boots after this patch (seems to be the case).

We can do away with the list_empty() check because the bare
list_for_each_entry_rcu() reduces to that now that we've removed
everything else.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.527608793@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:36 +01:00
Peter Zijlstra
d6ff86cfb5 perf: Optimize perf_event_task_ctx()
Remove a rcu_read_{,un}lock() pair and a few conditionals.

We can remove the rcu_read_lock() by increasing the scope of one
in the calling function.

We can do away with the system_state check if the machine still
boots after this patch (seems to be the case).

We can do away with the list_empty() check because the bare
list_for_each_entry_rcu() reduces to that now that we've removed
everything else.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.452227115@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:36 +01:00
Peter Zijlstra
8152018387 perf: Optimize perf_swevent_ctx_event()
Remove a rcu_read_{,un}lock() pair and a few conditionals.

We can remove the rcu_read_lock() by increasing the scope of one
in the calling function.

We can do away with the system_state check if the machine still
boots after this patch (seems to be the case).

We can do away with the list_empty() check because the bare
list_for_each_entry_rcu() reduces to that now that we've removed
everything else.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.378188589@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:35 +01:00
Peter Zijlstra
0cff784ae4 perf: Optimize some swcounter attr.sample_period==1 paths
Avoid the rather expensive perf_swevent_set_period() if we know
we have to sample every single event anyway.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.299508332@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:35 +01:00
Peter Zijlstra
453f19eea7 perf: Allow for custom overflow handlers
in-kernel perf users might wish to have custom actions on the
sample interrupt.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091120212508.222339539@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:35 +01:00
Arnaldo Carvalho de Melo
ef6ae72425 perf symbols: Change the kernel DSO name if it comes from kallsyms
So that the user have a clearer indication about the source of
the symbols, as we only state buildid mismatches in verbose
mode, because 'perf top' would overwrite such warning anyway.

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: <1258757489-5978-6-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:34 +01:00
Arnaldo Carvalho de Melo
fbd733b815 perf symbols: Check vmlinux buildid
E.g.:

[root@doppio linux-2.6-tip]# perf top -v --vmlinux
../build/tip/vmlinux > /dev/null build_id in vmlinux is
e96699725a47413a50c231864a8e7a8ced40a31b while expected is
18e7cc53db62a7d35e9d6f6c9ddc23017d38ee9a, ignoring it

I.e. perf top was told to use a vmlinux file that is not the one
currently running on the machine, it ignores it and falls back
to using /proc/kallsyms.

This solves many, at first, mysterious results when people have
a stale vmlinux file while keeping the default of trying to use
the vmlinux file in the current directory in things like 'perf
annotate' where the DWARF info is required and thus we can't use
just /proc/kallsyms.

Modules buildids are already being checked as of the previous
changeset in this series, because we are using the default
dso__load routine, that will look at a series of places looking
for the best file with a matching buildid, starting in the
-debuginfo directories.

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: <1258757489-5978-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:11:34 +01:00