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  1. 01 Oct, 2009 2 commits
    • Xiao Guangrong's avatar
      perf_event: Fix event group handling in __perf_event_sched_*() · 8c9ed8e1
      Xiao Guangrong authored 
      Paul Mackerras says:

 "Actually, looking at this more closely, it has to be a group
 leader anyway since it's at the top level of ctx->group_list.  In
 fact I see four places where we do:

  list_for_each_entry(event, &ctx->group_list, group_entry) {
	if (event == event->group_leader)
		...

 or the equivalent, three of which appear to have been introduced
 by afedadf2 ("perf_counter: Optimize sched in/out of counters")
 back in May by Peter Z.

 As far as I can see the if () is superfluous in each case (a
 singleton event will be a group of 1 and will have its
 group_leader pointing to itself)."

 [ See: http://marc.info/?l=linux-kernel&m=125361238901442&w=2 ]

And Peter Zijlstra points out this is a bugfix:

 "The intent was to call event_sched_{in,out}() for single event
  groups because that's cheaper than group_sched_{in,out}(),
  however..

  - as you noticed, I got the condition wrong, it should have read:

      list_empty(&event->sibling_list)

  - it failed to call group_can_go_on() which deals with ->exclusive.

  - it also doesn't call hw_perf_group_sched_in() which might break
    power."

 [ See: http://marc.info/?l=linux-kernel&m=125369523318583&w=2 ]

Changelog v1->v2:

 - Fix the title name according to Peter Zijlstra's suggestion

 - Remove the comments and WARN_ON_ONCE() as Peter Zijlstra's
   suggestion
Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: default avatarPeter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4ABC5A55.7000208@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8c9ed8e1
    • Arjan van de Ven's avatar
      perf timechart: Add a power-only mode · 39a90a8e
      Arjan van de Ven authored 
      For doing work on the Linux power management components, I need to
make long (30+ seconds) traces. Currently, this then results in a
HUGE svg file, with mostly process data that isn't interesting.

This patch adds a --power-only mode to perf timechart that only
outputs the CPU power section of the SVG; this significantly
reduces the size of the SVG file, making even 30+ second traces
viewable with inkscape.

As a minor tweak for the same effect, the minimum text size is
decreased; current inkscape cannot zoom in deep enough to show text
this small, but it reduces inkscape compute time.
Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
Cc: peterz@infradead.org
LKML-Reference: <20090924154013.0675ab71@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      39a90a8e
  3. 30 Sep, 2009 1 commit
  5. 27 Sep, 2009 14 commits
  7. 26 Sep, 2009 21 commits
  9. 25 Sep, 2009 2 commits
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