1. 17 3月, 2010 1 次提交
    • F
      perf: Fix unexported generic perf_arch_fetch_caller_regs · dcd5c166
      Frederic Weisbecker 提交于
      perf_arch_fetch_caller_regs() is exported for the overriden x86
      version, but not for the generic weak version.
      
      As a general rule, weak functions should not have their symbol
      exported in the same file they are defined.
      
      So let's export it on trace_event_perf.c as it is used by trace
      events only.
      
      This fixes:
      
      	ERROR: ".perf_arch_fetch_caller_regs" [fs/xfs/xfs.ko] undefined!
      	ERROR: ".perf_arch_fetch_caller_regs" [arch/powerpc/platforms/cell/spufs/spufs.ko] undefined!
      
      -v2: And also only build it if trace events are enabled.
      -v3: Fix changelog mistake
      Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <1268697902-9518-1-git-send-regression-fweisbec@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      dcd5c166
  2. 11 3月, 2010 3 次提交
  3. 10 3月, 2010 8 次提交
    • F
      perf: Drop the obsolete profile naming for trace events · 97d5a220
      Frederic Weisbecker 提交于
      Drop the obsolete "profile" naming used by perf for trace events.
      Perf can now do more than simple events counting, so generalize
      the API naming.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Jason Baron <jbaron@redhat.com>
      97d5a220
    • F
      perf: Take a hot regs snapshot for trace events · c530665c
      Frederic Weisbecker 提交于
      We are taking a wrong regs snapshot when a trace event triggers.
      Either we use get_irq_regs(), which gives us the interrupted
      registers if we are in an interrupt, or we use task_pt_regs()
      which gives us the state before we entered the kernel, assuming
      we are lucky enough to be no kernel thread, in which case
      task_pt_regs() returns the initial set of regs when the kernel
      thread was started.
      
      What we want is different. We need a hot snapshot of the regs,
      so that we can get the instruction pointer to record in the
      sample, the frame pointer for the callchain, and some other
      things.
      
      Let's use the new perf_fetch_caller_regs() for that.
      
      Comparison with perf record -e lock: -R -a -f -g
      Before:
      
              perf  [kernel]                   [k] __do_softirq
                     |
                     --- __do_softirq
                        |
                        |--55.16%-- __open
                        |
                         --44.84%-- __write_nocancel
      
      After:
      
                  perf  [kernel]           [k] perf_tp_event
                     |
                     --- perf_tp_event
                        |
                        |--41.07%-- lock_acquire
                        |          |
                        |          |--39.36%-- _raw_spin_lock
                        |          |          |
                        |          |          |--7.81%-- hrtimer_interrupt
                        |          |          |          smp_apic_timer_interrupt
                        |          |          |          apic_timer_interrupt
      
      The old case was producing unreliable callchains. Now having
      right frame and instruction pointers, we have the trace we
      want.
      
      Also syscalls and kprobe events already have the right regs,
      let's use them instead of wasting a retrieval.
      
      v2: Follow the rename perf_save_regs() -> perf_fetch_caller_regs()
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: Archs <linux-arch@vger.kernel.org>
      c530665c
    • F
      perf: Introduce new perf_fetch_caller_regs() for hot regs snapshot · 5331d7b8
      Frederic Weisbecker 提交于
      Events that trigger overflows by interrupting a context can
      use get_irq_regs() or task_pt_regs() to retrieve the state
      when the event triggered. But this is not the case for some
      other class of events like trace events as tracepoints are
      executed in the same context than the code that triggered
      the event.
      
      It means we need a different api to capture the regs there,
      namely we need a hot snapshot to get the most important
      informations for perf: the instruction pointer to get the
      event origin, the frame pointer for the callchain, the code
      segment for user_mode() tests (we always use __KERNEL_CS as
      trace events always occur from the kernel) and the eflags
      for further purposes.
      
      v2: rename perf_save_regs to perf_fetch_caller_regs as per
      Masami's suggestion.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: Archs <linux-arch@vger.kernel.org>
      5331d7b8
    • F
      lockdep: Move lock events under lockdep recursion protection · db2c4c77
      Frederic Weisbecker 提交于
      There are rcu locked read side areas in the path where we submit
      a trace event. And these rcu_read_(un)lock() trigger lock events,
      which create recursive events.
      
      One pair in do_perf_sw_event:
      
      __lock_acquire
            |
            |--96.11%-- lock_acquire
            |          |
            |          |--27.21%-- do_perf_sw_event
            |          |          perf_tp_event
            |          |          |
            |          |          |--49.62%-- ftrace_profile_lock_release
            |          |          |          lock_release
            |          |          |          |
            |          |          |          |--33.85%-- _raw_spin_unlock
      
      Another pair in perf_output_begin/end:
      
      __lock_acquire
            |--23.40%-- perf_output_begin
            |          |          __perf_event_overflow
            |          |          perf_swevent_overflow
            |          |          perf_swevent_add
            |          |          perf_swevent_ctx_event
            |          |          do_perf_sw_event
            |          |          perf_tp_event
            |          |          |
            |          |          |--55.37%-- ftrace_profile_lock_acquire
            |          |          |          lock_acquire
            |          |          |          |
            |          |          |          |--37.31%-- _raw_spin_lock
      
      The problem is not that much the trace recursion itself, as we have a
      recursion protection already (though it's always wasteful to recurse).
      But the trace events are outside the lockdep recursion protection, then
      each lockdep event triggers a lock trace, which will trigger two
      other lockdep events. Here the recursive lock trace event won't
      be taken because of the trace recursion, so the recursion stops there
      but lockdep will still analyse these new events:
      
      To sum up, for each lockdep events we have:
      
      	lock_*()
      	     |
                   trace lock_acquire
                        |
                        ----- rcu_read_lock()
                        |          |
                        |          lock_acquire()
                        |          |
                        |          trace_lock_acquire() (stopped)
                        |          |
      		  |          lockdep analyze
                        |
                        ----- rcu_read_unlock()
                                   |
                                   lock_release
                                   |
                                   trace_lock_release() (stopped)
                                   |
                                   lockdep analyze
      
      And you can repeat the above two times as we have two rcu read side
      sections when we submit an event.
      
      This is fixed in this patch by moving the lock trace event under
      the lockdep recursion protection.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      db2c4c77
    • P
      perf: Provide better condition for event rotation · d4944a06
      Peter Zijlstra 提交于
      Try to avoid useless rotation and PMU disables.
      
      [ Could be improved by keeping a nr_runnable count to better account
        for the < PERF_STAT_INACTIVE counters ]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
      Cc: paulus@samba.org
      Cc: eranian@google.com
      Cc: robert.richter@amd.com
      Cc: fweisbec@gmail.com
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d4944a06
    • P
      perf: Optimize perf_disable · 32975a4f
      Peter Zijlstra 提交于
      Currently we always call hw_perf_disable(), even if its already disabled,
      this seems superflous, esp. since it cannot be made NMI safe (see further
      patches).
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: paulus@samba.org
      Cc: eranian@google.com
      Cc: robert.richter@amd.com
      Cc: fweisbec@gmail.com
      Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      32975a4f
    • P
      perf: Rework and fix the arch CPU-hotplug hooks · 3f6da390
      Peter Zijlstra 提交于
      Remove the hw_perf_event_*() hotplug hooks in favour of per PMU hotplug
      notifiers. This has the advantage of reducing the static weak interface
      as well as exposing all hotplug actions to the PMU.
      
      Use this to fix x86 hotplug usage where we did things in ONLINE which
      should have been done in UP_PREPARE or STARTING.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: paulus@samba.org
      Cc: eranian@google.com
      Cc: robert.richter@amd.com
      Cc: fweisbec@gmail.com
      Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
      LKML-Reference: <20100305154128.736225361@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3f6da390
    • P
      perf: Provide generic perf_sample_data initialization · dc1d628a
      Peter Zijlstra 提交于
      This makes it easier to extend perf_sample_data and fixes a bug on arm
      and sparc, which failed to set ->raw to NULL, which can cause crashes
      when combined with PERF_SAMPLE_RAW.
      
      It also optimizes PowerPC and tracepoint, because the struct
      initialization is forced to zero out the whole structure.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NJean Pihet <jpihet@mvista.com>
      Reviewed-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Cc: Jamie Iles <jamie.iles@picochip.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: stable@kernel.org
      LKML-Reference: <20100304140100.315416040@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      dc1d628a
  4. 08 3月, 2010 5 次提交
  5. 07 3月, 2010 16 次提交
  6. 04 3月, 2010 5 次提交
  7. 03 3月, 2010 1 次提交
  8. 02 3月, 2010 1 次提交