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| author | Davidlohr Bueso <dave@stgolabs.net> | 2021-08-08 21:33:01 -0700 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2021-08-09 12:00:27 -0300 |
| commit | 46f815323b5a8f0e7156f50ea87c354424210e97 (patch) | |
| tree | 08e481b78056b0e996ae53efad2136b5c6ef576b /tools/perf/bench/futex.h | |
| parent | 6f9661b25b1741b180bdaeb85853905078cfd9d8 (diff) | |
| download | lwn-46f815323b5a8f0e7156f50ea87c354424210e97.tar.gz lwn-46f815323b5a8f0e7156f50ea87c354424210e97.zip | |
perf bench futex, requeue: Add --pi parameter
This extends the program to measure WAIT_REQUEUE_PI+CMP_REQUEUE_PI
pairs, which are the underlying machinery behind priority-inheritance
aware condition variables. The defaults are the same as with the regular
non-pi version, requeueing one task at a time, with the exception that
PI will always wakeup the first waiter.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20210809043301.66002-8-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/bench/futex.h')
| -rw-r--r-- | tools/perf/bench/futex.h | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h index 40a89f192c53..b3853aac3021 100644 --- a/tools/perf/bench/futex.h +++ b/tools/perf/bench/futex.h @@ -18,6 +18,7 @@ struct bench_futex_parameters { bool fshared; bool mlockall; bool multi; /* lock-pi */ + bool pi; /* requeue-pi */ bool broadcast; /* requeue */ unsigned int runtime; /* seconds*/ unsigned int nthreads; @@ -90,7 +91,7 @@ futex_unlock_pi(u_int32_t *uaddr, int opflags) /** * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2 * @nr_wake: wake up to this many tasks -* @nr_requeue: requeue up to this many tasks +* @nr_requeue: requeue up to this many tasks */ static inline int futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake, @@ -99,4 +100,38 @@ futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wak return futex(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2, val, opflags); } + +/** + * futex_wait_requeue_pi() - block on uaddr and prepare to requeue to uaddr2 + * @uaddr: non-PI futex source + * @uaddr2: PI futex target + * + * This is the first half of the requeue_pi mechanism. It shall always be + * paired with futex_cmp_requeue_pi(). + */ +static inline int +futex_wait_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, + struct timespec *timeout, int opflags) +{ + return futex(uaddr, FUTEX_WAIT_REQUEUE_PI, val, timeout, uaddr2, 0, + opflags); +} + +/** + * futex_cmp_requeue_pi() - requeue tasks from uaddr to uaddr2 + * @uaddr: non-PI futex source + * @uaddr2: PI futex target + * @nr_requeue: requeue up to this many tasks + * + * This is the second half of the requeue_pi mechanism. It shall always be + * paired with futex_wait_requeue_pi(). The first waker is always awoken. + */ +static inline int +futex_cmp_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, + int nr_requeue, int opflags) +{ + return futex(uaddr, FUTEX_CMP_REQUEUE_PI, 1, nr_requeue, uaddr2, + val, opflags); +} + #endif /* _FUTEX_H */ |