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| author | Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> | 2015-09-04 03:07:45 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-09-13 09:27:25 (GMT) |
| commit | fbbe07011581990ef74dfac06dc8511b1a14badb (patch) | |
| tree | 8b026523a68ff8d98107a393d0551c9bfbf00812 /include | |
| parent | 845583767c306dac0290aab908c18b01772ea4b4 (diff) | |
| download | linux-fbbe07011581990ef74dfac06dc8511b1a14badb.tar.xz | |
perf/core: Add a 'flags' parameter to the PMU transactional interfaces
Currently, the PMU interface allows reading only one counter at a time.
But some PMUs like the 24x7 counters in Power, support reading several
counters at once. To leveage this functionality, extend the transaction
interface to support a "transaction type".
The first type, PERF_PMU_TXN_ADD, refers to the existing transactions,
i.e. used to _schedule_ all the events on the PMU as a group. A second
transaction type, PERF_PMU_TXN_READ, will be used in a follow-on patch,
by the 24x7 counters to read several counters at once.
Extend the transaction interfaces to the PMU to accept a 'txn_flags'
parameter and use this parameter to ignore any transactions that are
not of type PERF_PMU_TXN_ADD.
Thanks to Peter Zijlstra for his input.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[peterz: s390 compile fix]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Michael 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/1441336073-22750-3-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/perf_event.h | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index d61ee44..ea3b5dd 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -201,6 +201,8 @@ struct perf_event; */ #define PERF_EVENT_TXN 0x1 +#define PERF_PMU_TXN_ADD 0x1 /* txn to add/schedule event on PMU */ + /** * pmu::capabilities flags */ @@ -331,20 +333,26 @@ struct pmu { * * Start the transaction, after this ->add() doesn't need to * do schedulability tests. + * + * Optional. */ - void (*start_txn) (struct pmu *pmu); /* optional */ + void (*start_txn) (struct pmu *pmu, unsigned int txn_flags); /* * If ->start_txn() disabled the ->add() schedulability test * then ->commit_txn() is required to perform one. On success * the transaction is closed. On error the transaction is kept * open until ->cancel_txn() is called. + * + * Optional. */ - int (*commit_txn) (struct pmu *pmu); /* optional */ + int (*commit_txn) (struct pmu *pmu); /* * Will cancel the transaction, assumes ->del() is called * for each successful ->add() during the transaction. + * + * Optional. */ - void (*cancel_txn) (struct pmu *pmu); /* optional */ + void (*cancel_txn) (struct pmu *pmu); /* * Will return the value for perf_event_mmap_page::index for this event, |