diff options
Diffstat (limited to 'absl/base/internal/cycleclock.h')
| -rw-r--r-- | absl/base/internal/cycleclock.h | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/absl/base/internal/cycleclock.h b/absl/base/internal/cycleclock.h index ae5ede3e..39bce06a 100644 --- a/absl/base/internal/cycleclock.h +++ b/absl/base/internal/cycleclock.h @@ -5,7 +5,7 @@ // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // -// http://www.apache.org/licenses/LICENSE-2.0 +// https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, @@ -28,7 +28,6 @@ // not necessarily "CPU cycles" and code should not rely on that behavior, even // if experimentally observed. // -// // An arbitrary offset may have been added to the counter at power on. // // On some platforms, the rate and offset of the counter may differ @@ -46,7 +45,7 @@ #include <cstdint> namespace absl { -inline namespace lts_2018_12_18 { +inline namespace lts_2019_08_08 { namespace base_internal { // ----------------------------------------------------------------------------- @@ -72,8 +71,22 @@ class CycleClock { CycleClock& operator=(const CycleClock&) = delete; }; +using CycleClockSourceFunc = int64_t (*)(); + +class CycleClockSource { + private: + // CycleClockSource::Register() + // + // Register a function that provides an alternate source for the unscaled CPU + // cycle count value. The source function must be async signal safe, must not + // call CycleClock::Now(), and must have a frequency that matches that of the + // unscaled clock used by CycleClock. A nullptr value resets CycleClock to use + // the default source. + static void Register(CycleClockSourceFunc source); +}; + } // namespace base_internal -} // inline namespace lts_2018_12_18 +} // inline namespace lts_2019_08_08 } // namespace absl #endif // ABSL_BASE_INTERNAL_CYCLECLOCK_H_ |