From 0399f5fc547ef035c4eb5e383f30b28ae73d936e Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Thu, 16 Jul 2015 11:27:00 +0200 Subject: erts: Refactor perf counter internal interface perf counter is now part of the function pointer interface and also the function returns the value instead of writing to a memory buffer. --- erts/emulator/beam/erl_time_sup.c | 66 ++------------------------------------- 1 file changed, 2 insertions(+), 64 deletions(-) (limited to 'erts/emulator/beam/erl_time_sup.c') diff --git a/erts/emulator/beam/erl_time_sup.c b/erts/emulator/beam/erl_time_sup.c index 6509c6a805..98159fdf72 100644 --- a/erts/emulator/beam/erl_time_sup.c +++ b/erts/emulator/beam/erl_time_sup.c @@ -2444,72 +2444,10 @@ BIF_RETTYPE os_system_time_1(BIF_ALIST_1) BIF_RETTYPE os_perf_counter_0(BIF_ALIST_0) { - ErtsSysHrTime pcounter; - sys_perf_counter(&pcounter); - BIF_RET(make_time_val(BIF_P, pcounter)); + BIF_RET(make_time_val(BIF_P, erts_sys_perf_counter())); } BIF_RETTYPE erts_internal_perf_counter_unit_0(BIF_ALIST_0) { - BIF_RET(make_time_val(BIF_P, SYS_PERF_COUNTER_UNIT)); -} - -/* What resolution to spin to in micro seconds */ -#define RESOLUTION 100 -/* How many iterations to spin */ -#define ITERATIONS 1 -/* How many significant figures to round to */ -#define SIGFIGS 3 - -static ErtsSysHrTime perf_counter_unit = 0; - -static ErtsSysHrTime erts_calculate_perf_counter_unit(void); -static ErtsSysHrTime erts_calculate_perf_counter_unit() { - int i; - ErtsSysHrTime pre, post; - double value = 0; - double round_factor; -#if defined(HAVE_GETHRTIME) && defined(GETHRTIME_WITH_CLOCK_GETTIME) - struct timespec basetime,comparetime; -#define __GETTIME(arg) clock_gettime(CLOCK_MONOTONIC,arg) -#define __GETUSEC(arg) (arg.tv_nsec / 1000) -#else - SysTimeval basetime,comparetime; -#define __GETTIME(arg) sys_gettimeofday(arg) -#define __GETUSEC(arg) arg.tv_usec -#endif - - for (i = 0; i < ITERATIONS; i++) { - /* Make sure usec just flipped over at current resolution */ - __GETTIME(&basetime); - do { - __GETTIME(&comparetime); - } while ((__GETUSEC(basetime) / RESOLUTION) == (__GETUSEC(comparetime) / RESOLUTION)); - - sys_perf_counter(&pre); - - __GETTIME(&basetime); - do { - __GETTIME(&comparetime); - } while ((__GETUSEC(basetime) / RESOLUTION) == (__GETUSEC(comparetime) / RESOLUTION)); - - sys_perf_counter(&post); - - value += post - pre; - } - /* After this value is ticks per us */ - value /= (RESOLUTION*ITERATIONS); - - /* We round to 3 significant figures */ - round_factor = pow(10.0, SIGFIGS - ceil(log10(value))); - value = ((ErtsSysHrTime)(value * round_factor + 0.5)) / round_factor; - - /* convert to ticks per second */ - return 1000000 * value; -} - -ErtsSysHrTime erts_perf_counter_unit() { - if (perf_counter_unit == 0) - perf_counter_unit = erts_calculate_perf_counter_unit(); - return perf_counter_unit; + BIF_RET(make_time_val(BIF_P, erts_sys_perf_counter_unit())); } -- cgit v1.2.3