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  1. 17 11月, 2009 8 次提交
  3. 16 11月, 2009 1 次提交
    • P
      perf_event: Optimize perf_output_lock() · 559fdc3c
      由 Peter Zijlstra 提交于 
      The purpose of perf_output_{un,}lock() is to:

 1) avoid publishing incomplete data
    [ possible when publishing a head that is ahead of an entry
      that is still being written ]

 2) guarantee fwd progress
    [ a simple refcount on pending writers doesn't need to drop to
      0, making it so would end up implementing something like forced
      quiecent states of RCU ]

To satisfy the above without undue complexity it serializes
between CPUs, this means that a pending writer can only be the
same cpu in a nested context, and since (under normal operation)
a cpu always makes progress we're good -- if the head is only
published when the bottom  most writer completes.

Now we don't need to disable IRQs in order to serialize between
CPUs, disabling preemption ought to be sufficient, esp since we
already deal with nesting due to NMIs.

This avoids potentially expensive (and needless) local IRQ
disable/enable ops.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1258373161.26714.254.camel@laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      559fdc3c
  5. 15 11月, 2009 4 次提交
    • L
      perf stat: Do not print ratio when task-clock event is not counted · 7255fe2a
      由 Lucas De Marchi 提交于 
      The ratio between the number of events and the time elapsed makes
sense only if task-clock event is counted. Otherwise it will be
simply a (confusing)

	#      0.000 M/sec

This patch outputs the ratio only if task-clock event is counted.
Some test examples of before and after:

Before:

 [lucas@skywalker linux.trees.git]$ sudo perf stat -e branch-misses -a -- sleep 1

	 Performance counter stats for 'sleep 1':

		1367818  branch-misses            #      0.000 M/sec

	    1.001494325  seconds time elapsed

After (without task-clock):

 [lucas@skywalker perf]$ sudo ./perf stat -e branch-misses -a -- sleep 1

	 Performance counter stats for 'sleep 1':

		1135044  branch-misses

	    1.001370775  seconds time elapsed

After (with task-clock):

 [lucas@skywalker perf]$ sudo ./perf stat -e branch-misses -e task-clock -a -- sleep 1

	 Performance counter stats for 'sleep 1':

		1070111  branch-misses            #      0.534 M/sec
	    2002.730893  task-clock-msecs         #      1.999 CPUs

	    1.001640292  seconds time elapsed
Signed-off-by: NLucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091115140507.GB21561@skywalker.lan>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7255fe2a
    • H
      perf tools: Add new perf_atoll() function to parse string representing size in bytes · d2fb8b41
      由 Hitoshi Mitake 提交于 
      This patch modifies util/string.[ch] to add new function:
perf_atoll() to parse string representing size in bytes.

This function parses (\d+)(b|B|kb|KB|mb|MB|gb|GB) (e.g. "256MB")
and returns its numeric value. (e.g. 268435456)
Signed-off-by: NHitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1258285013-4759-1-git-send-email-mitake@dcl.info.waseda.ac.jp>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d2fb8b41
    • I
      Merge branches 'perf/powerpc' and 'perf/bench' into perf/core · 0ffa798d
      由 Ingo Molnar 提交于 
      Merge reason: Both 'perf bench' and the pending PowerPC changes
              are now ready for the next merge window.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      0ffa798d
    • I
      Merge commit 'v2.6.32-rc7' into perf/core · 39dc78b6
      由 Ingo Molnar 提交于 
      Merge reason: pick up perf fixlets
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      39dc78b6
  7. 14 11月, 2009 1 次提交
  9. 13 11月, 2009 3 次提交
  11. 12 11月, 2009 23 次提交