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  1. 14 Apr, 2010 2 commits
    • Frederic Weisbecker's avatar
      perf: Store active software events in a hashlist · 76e1d904
      Frederic Weisbecker authored 
      Each time a software event triggers, we need to walk through
the entire list of events from the current cpu and task contexts
to retrieve a running perf event that matches.
We also need to check a matching perf event is actually counting.

This walk is wasteful and makes the event fast path scaling
down with a growing number of events running on the same
contexts.

To solve this, we store the running perf events in a hashlist to
get an immediate access to them against their type:event_id when
they trigger.

v2: - Fix SWEVENT_HLIST_SIZE definition (and re-learn some basic
      maths along the way)
    - Only allocate hlist for online cpus, but keep track of the
      refcount on offline possible cpus too, so that we allocate it
      if needed when it becomes online.
    - Drop the kref use as it's not adapted to our tricks anymore.

v3: - Fix bad refcount check (address instead of value). Thanks to
      Eric Dumazet who spotted this.
    - While exiting cpu, move the hlist release out of the IPI path
      to lock the hlist mutex sanely.
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
      76e1d904
    • Ian Munsie's avatar
      perf: Fix endianness argument compatibility with OPT_BOOLEAN() and introduce OPT_INCR() · c0555642
      Ian Munsie authored 
      Parsing an option from the command line with OPT_BOOLEAN on a
bool data type would not work on a big-endian machine due to the
manner in which the boolean was being cast into an int and
incremented. For example, running 'perf probe --list' on a
PowerPC machine would fail to properly set the list_events bool
and would therefore print out the usage information and
terminate.

This patch makes OPT_BOOLEAN work as expected with a bool
datatype. For cases where the original OPT_BOOLEAN was
intentionally being used to increment an int each time it was
passed in on the command line, this patch introduces OPT_INCR
with the old behaviour of OPT_BOOLEAN (the verbose variable is
currently the only such example of this).

I have reviewed every use of OPT_BOOLEAN to verify that a true
C99 bool was passed. Where integers were used, I verified that
they were only being used for boolean logic and changed them to
bools to ensure that they would not be mistakenly used as ints.
The major exception was the verbose variable which now uses
OPT_INCR instead of OPT_BOOLEAN.
Signed-off-by: default avatarIan Munsie <imunsie@au.ibm.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
Cc: <stable@kernel.org> # NOTE: wont apply to .3[34].x cleanly, please backport
Cc: Git development list <git@vger.kernel.org>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: WANG Cong <amwang@redhat.com>
Cc: Thiago Farina <tfransosi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1271147857-11604-1-git-send-email-imunsie@au.ibm.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c0555642
  3. 09 Apr, 2010 1 commit
  5. 08 Apr, 2010 13 commits
  7. 07 Apr, 2010 24 commits
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