diff options
| author |  Dmitry Vyukov <dvyukov@google.com> | 2023-09-20 10:26:25 -0700 |
|---|---|---|
| committer |  Copybara-Service <copybara-worker@google.com> | 2023-09-20 10:27:09 -0700 |
| commit | c45a4393c075fb0e50e408d9b69035a42ed2617c (patch) | |
| tree | 2b0e228ce7a1a564b5d5d9724257706307c606e5 /absl/synchronization/mutex.h | |
| parent | adcaae433fe10da72bc4f8b61eaf559604b81d03 (diff) | |
absl:speed up Mutex::[Reader]TryLock
Tidy up Mutex::[Reader]TryLock codegen by outlining slow path
and non-tail function call, and un-unrolling the loop.
Current codegen:
https://gist.githubusercontent.com/dvyukov/a4d353fd71ac873af9332c1340675b60/raw/226537ffa305b25a79ef3a85277fa870fee5191d/gistfile1.txt
New codegen:
https://gist.githubusercontent.com/dvyukov/686a094c5aa357025689764f155e5a29/raw/e3125c1cdb5669fac60faf336e2f60395e29d888/gistfile1.txt
name old cpu/op new cpu/op delta
BM_TryLock 18.0ns ± 0% 17.7ns ± 0% -1.64% (p=0.016 n=4+5)
BM_ReaderTryLock/real_time/threads:1 17.9ns ± 0% 17.9ns ± 0% -0.10% (p=0.016 n=5+5)
BM_ReaderTryLock/real_time/threads:72 9.61µs ± 8% 8.42µs ± 7% -12.37% (p=0.008 n=5+5)
PiperOrigin-RevId: 567006472
Change-Id: Iea0747e71bbf2dc1f00c70a4235203071d795b99
Diffstat (limited to 'absl/synchronization/mutex.h')
| -rw-r--r-- | absl/synchronization/mutex.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/absl/synchronization/mutex.h b/absl/synchronization/mutex.h index d146b066..95726f6b 100644 --- a/absl/synchronization/mutex.h +++ b/absl/synchronization/mutex.h @@ -521,6 +521,10 @@ class ABSL_LOCKABLE Mutex { int flags) ABSL_ATTRIBUTE_COLD; // slow path release void UnlockSlow(SynchWaitParams* waitp) ABSL_ATTRIBUTE_COLD; + // TryLock slow path. + bool TryLockSlow(); + // ReaderTryLock slow path. + bool ReaderTryLockSlow(); // Common code between Await() and AwaitWithTimeout/Deadline() bool AwaitCommon(const Condition& cond, synchronization_internal::KernelTimeout t); |