| /* |
| * |
| * Copyright 2015, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #include <grpc/support/log.h> |
| #include <grpc/support/time.h> |
| #include <stdio.h> |
| |
| #ifdef GRPC_TIMERS_RDTSC |
| #if defined(__i386__) |
| static void gpr_get_cycle_counter(long long int *clk) { |
| long long int ret; |
| __asm__ volatile("rdtsc" : "=A"(ret)); |
| *clk = ret; |
| } |
| |
| // ---------------------------------------------------------------- |
| #elif defined(__x86_64__) || defined(__amd64__) |
| static void gpr_get_cycle_counter(long long int *clk) { |
| unsigned long long low, high; |
| __asm__ volatile("rdtsc" : "=a"(low), "=d"(high)); |
| *clk = (long long)(high << 32) | (long long)low; |
| } |
| #endif |
| |
| static double cycles_per_second = 0; |
| static long long int start_cycle; |
| void gpr_precise_clock_init(void) { |
| time_t start; |
| long long end_cycle; |
| gpr_log(GPR_DEBUG, "Calibrating timers"); |
| start = time(NULL); |
| while (time(NULL) == start) |
| ; |
| gpr_get_cycle_counter(&start_cycle); |
| while (time(NULL) <= start + 10) |
| ; |
| gpr_get_cycle_counter(&end_cycle); |
| cycles_per_second = (double)(end_cycle - start_cycle) / 10.0; |
| gpr_log(GPR_DEBUG, "... cycles_per_second = %f\n", cycles_per_second); |
| } |
| |
| void gpr_precise_clock_now(gpr_timespec *clk) { |
| long long int counter; |
| double secs; |
| gpr_get_cycle_counter(&counter); |
| secs = (double)(counter - start_cycle) / cycles_per_second; |
| clk->clock_type = GPR_CLOCK_PRECISE; |
| clk->tv_sec = (int64_t)secs; |
| clk->tv_nsec = (int32_t)(1e9 * (secs - (double)clk->tv_sec)); |
| } |
| |
| #else /* GRPC_TIMERS_RDTSC */ |
| void gpr_precise_clock_init(void) {} |
| |
| void gpr_precise_clock_now(gpr_timespec *clk) { |
| *clk = gpr_now(GPR_CLOCK_REALTIME); |
| clk->clock_type = GPR_CLOCK_PRECISE; |
| } |
| #endif /* GRPC_TIMERS_RDTSC */ |