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  1. 16 Sep, 2015 1 commit
    • Ingo Molnar's avatar
      Merge tag 'perf-core-for-mingo' of... · a4d71093
      Ingo Molnar authored 
      Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

User visible changes:

- Enhance the error reporting of tracepoint event parsing, e.g.:

    $ oldperf record -e sched:sched_switc usleep 1
    event syntax error: 'sched:sched_switc'
                         \___ unknown tracepoint
    Run 'perf list' for a list of valid events

  Now we get the much nicer:

    $ perf record -e sched:sched_switc ls
    event syntax error: 'sched:sched_switc'
                         \___ can't access trace events

    Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_switc
    Hint:  Try 'sudo mount -o remount,mode=755 /sys/kernel/debug'

  And after we have those mount point permissions fixed:

    $ perf record -e sched:sched_switc ls
    event syntax error: 'sched:sched_switc'
                         \___ unknown tracepoint

    Error: File /sys/kernel/debug/tracing/events/sched/sched_switc not found.
    Hint:  Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

  Now its just a matter of using what git uses to suggest alternatives when we
  make a typo, i.e. that it is just an 'h' missing :-)

  I.e. basically now the event parsing routing uses the strerror_open()
  routines introduced by and used in 'perf trace' work. (Jiri Olsa)

Infrastructure changes:

- Export init/exit_probe_symbol_maps() from 'perf probe' for use in eBPF.
  (Namhyung Kim)

- Free perf_probe_event in cleanup_perf_probe_events(). (Namhyung Kim)

- regs_query_register_offset() infrastructure + implementation for x86.
  First user will be the perf/eBPF code. (Wang Nan)
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      a4d71093
  3. 15 Sep, 2015 9 commits
  5. 14 Sep, 2015 27 commits
  7. 13 Sep, 2015 3 commits
    • Sukadev Bhattiprolu's avatar
      perf/core: Drop PERF_EVENT_TXN · 8f3e5684
      Sukadev Bhattiprolu authored 
      We currently use PERF_EVENT_TXN flag to determine if we are in the middle
of a transaction. If in a transaction, we defer the schedulability checks
from pmu->add() operation to the pmu->commit() operation.

Now that we have "transaction types" (PERF_PMU_TXN_ADD, PERF_PMU_TXN_READ)
we can use the type to determine if we are in a transaction and drop the
PERF_EVENT_TXN flag.

When PERF_EVENT_TXN is dropped, the cpuhw->group_flag on some architectures
becomes unused, so drop that field as well.

This is an extension of the Powerpc patch from Peter Zijlstra to s390,
Sparc and x86 architectures.
Signed-off-by: default avatarSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-11-git-send-email-sukadev@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      8f3e5684
    • Sukadev Bhattiprolu's avatar
      powerpc, perf/powerpc/hv-24x7: Use PMU_TXN_READ interface · 88a48613
      Sukadev Bhattiprolu authored 
      The 24x7 counters in Powerpc allow monitoring a large number of counters
simultaneously. They also allow reading several counters in a single
HCALL so we can get a more consistent snapshot of the system.

Use the PMU's transaction interface to monitor and read several event
counters at once. The idea is that users can group several 24x7 events
into a single group of events. We use the following logic to submit
the group of events to the PMU and read the values:

	pmu->start_txn()		// Initialize before first event

	for each event in group
		pmu->read(event);	// Queue each event to be read

	pmu->commit_txn()		// Read/update all queuedcounters

The ->commit_txn() also updates the event counts in the respective
perf_event objects.  The perf subsystem can then directly get the
event counts from the perf_event and can avoid submitting a new
->read() request to the PMU.

Thanks to input from Peter Zijlstra.
Signed-off-by: default avatarSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-10-git-send-email-sukadev@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      88a48613
    • Sukadev Bhattiprolu's avatar
      perf/core: Define PERF_PMU_TXN_READ interface · 4a00c16e
      Sukadev Bhattiprolu authored 
      Define a new PERF_PMU_TXN_READ interface to read a group of counters
at once.

        pmu->start_txn()                // Initialize before first event

        for each event in group
                pmu->read(event);       // Queue each event to be read

        rc = pmu->commit_txn()          // Read/update all queued counters

Note that we use this interface with all PMUs.  PMUs that implement this
interface use the ->read() operation to _queue_ the counters to be read
and use ->commit_txn() to actually read all the queued counters at once.

PMUs that don't implement PERF_PMU_TXN_READ ignore ->start_txn() and
->commit_txn() and continue to read counters one at a time.

Thanks to input from Peter Zijlstra.
Signed-off-by: default avatarSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1441336073-22750-9-git-send-email-sukadev@linux.vnet.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      4a00c16e
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