From a266236e856aec790b1757064eccff876fad4703 Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Wed, 10 Aug 2016 15:14:56 +0200 Subject: [PATCH] Add new *_atomic counter update function PR gcov-profile/58306 * Makefile.in: New functions (modules) are added. * libgcov-profiler.c (__gcov_interval_profiler_atomic): New function. (__gcov_pow2_profiler_atomic): New function. (__gcov_one_value_profiler_body): New argument is instroduced. (__gcov_one_value_profiler): Call with the new argument. (__gcov_one_value_profiler_atomic): Likewise. (__gcov_indirect_call_profiler_v2): Likewise. (__gcov_time_profiler_atomic): New function. (__gcov_average_profiler_atomic): Likewise. (__gcov_ior_profiler_atomic): Likewise. * libgcov.h: Declare the aforementioned functions. PR gcov-profile/58306 * gcc.dg/tree-prof/val-profiler-threads-1.c: New test. PR gcov-profile/58306 * tree-profile.c (gimple_init_edge_profiler): Create conditionally atomic variants of profile update functions. From-SVN: r239324 --- gcc/ChangeLog | 6 + gcc/testsuite/ChangeLog | 5 + .../gcc.dg/tree-prof/val-profiler-threads-1.c | 41 +++++++ gcc/tree-profile.c | 42 ++++--- libgcc/ChangeLog | 16 +++ libgcc/Makefile.in | 14 ++- libgcc/libgcov-profiler.c | 103 +++++++++++++++++- libgcc/libgcov.h | 7 ++ 8 files changed, 209 insertions(+), 25 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-prof/val-profiler-threads-1.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index cdf8b7740bd..7dbe48608f0 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2016-08-10 Martin Liska + + PR gcov-profile/58306 + * tree-profile.c (gimple_init_edge_profiler): Create conditionally + atomic variants of profile update functions. + 2016-08-10 Martin Liska Cherry picked (and modified) from google-4_7 branch diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 20bd72a0dbc..c9f58fec411 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2016-08-10 Martin Liska + + PR gcov-profile/58306 + * gcc.dg/tree-prof/val-profiler-threads-1.c: New test. + 2016-08-10 Martin Liska * g++.dg/gcov/gcov-threads-1.C: New test. diff --git a/gcc/testsuite/gcc.dg/tree-prof/val-profiler-threads-1.c b/gcc/testsuite/gcc.dg/tree-prof/val-profiler-threads-1.c new file mode 100644 index 00000000000..e9b04a0e67d --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-prof/val-profiler-threads-1.c @@ -0,0 +1,41 @@ +/* { dg-options "-O0 -pthread -fprofile-update=atomic" } */ +#include + +#define NUM_THREADS 8 +#define SIZE 1024 +#define ITERATIONS (1000 * 1000) + +char buffer[SIZE]; +char buffer2[SIZE]; + +void *copy_memory(char *dst, char *src, unsigned size) +{ + for (unsigned i = 0; i < ITERATIONS; i++) + { + dst[size % 10] = src[size % 20]; + } +} + +void *foo(void *d) +{ + copy_memory (buffer, buffer2, SIZE); +} + +int main(int argc, char *argv[]) +{ + pthread_t threads[NUM_THREADS]; + int rc; + long t; + for(t=0;t + + PR gcov-profile/58306 + * Makefile.in: New functions (modules) are added. + * libgcov-profiler.c (__gcov_interval_profiler_atomic): New + function. + (__gcov_pow2_profiler_atomic): New function. + (__gcov_one_value_profiler_body): New argument is instroduced. + (__gcov_one_value_profiler): Call with the new argument. + (__gcov_one_value_profiler_atomic): Likewise. + (__gcov_indirect_call_profiler_v2): Likewise. + (__gcov_time_profiler_atomic): New function. + (__gcov_average_profiler_atomic): Likewise. + (__gcov_ior_profiler_atomic): Likewise. + * libgcov.h: Declare the aforementioned functions. + 2016-08-09 Martin Liska * libgcov-util.c: Fix typo and GNU coding style. diff --git a/libgcc/Makefile.in b/libgcc/Makefile.in index efaf7f7bf1a..ba37c657baf 100644 --- a/libgcc/Makefile.in +++ b/libgcc/Makefile.in @@ -858,10 +858,18 @@ include $(iterator) LIBGCOV_MERGE = _gcov_merge_add _gcov_merge_single _gcov_merge_delta \ _gcov_merge_ior _gcov_merge_time_profile _gcov_merge_icall_topn -LIBGCOV_PROFILER = _gcov_interval_profiler _gcov_pow2_profiler \ +LIBGCOV_PROFILER = _gcov_interval_profiler \ + _gcov_interval_profiler_atomic \ + _gcov_pow2_profiler \ + _gcov_pow2_profiler_atomic \ _gcov_one_value_profiler \ - _gcov_average_profiler _gcov_ior_profiler \ - _gcov_indirect_call_profiler_v2 _gcov_time_profiler \ + _gcov_one_value_profiler_atomic \ + _gcov_average_profiler \ + _gcov_average_profiler_atomic \ + _gcov_ior_profiler \ + _gcov_ior_profiler_atomic \ + _gcov_indirect_call_profiler_v2 \ + _gcov_time_profiler \ _gcov_indirect_call_topn_profiler LIBGCOV_INTERFACE = _gcov_dump _gcov_flush _gcov_fork \ _gcov_execl _gcov_execlp \ diff --git a/libgcc/libgcov-profiler.c b/libgcc/libgcov-profiler.c index a99d93bb412..70a821dc625 100644 --- a/libgcc/libgcov-profiler.c +++ b/libgcc/libgcov-profiler.c @@ -46,6 +46,26 @@ __gcov_interval_profiler (gcov_type *counters, gcov_type value, } #endif +#ifdef L_gcov_interval_profiler_atomic +/* If VALUE is in interval , then increases the + corresponding counter in COUNTERS. If the VALUE is above or below + the interval, COUNTERS[STEPS] or COUNTERS[STEPS + 1] is increased + instead. Function is thread-safe. */ + +void +__gcov_interval_profiler_atomic (gcov_type *counters, gcov_type value, + int start, unsigned steps) +{ + gcov_type delta = value - start; + if (delta < 0) + __atomic_fetch_add (&counters[steps + 1], 1, MEMMODEL_RELAXED); + else if (delta >= steps) + __atomic_fetch_add (&counters[steps], 1, MEMMODEL_RELAXED); + else + __atomic_fetch_add (&counters[delta], 1, MEMMODEL_RELAXED); +} +#endif + #ifdef L_gcov_pow2_profiler /* If VALUE is a power of two, COUNTERS[1] is incremented. Otherwise COUNTERS[0] is incremented. */ @@ -60,6 +80,21 @@ __gcov_pow2_profiler (gcov_type *counters, gcov_type value) } #endif +#ifdef L_gcov_pow2_profiler_atomic +/* If VALUE is a power of two, COUNTERS[1] is incremented. Otherwise + COUNTERS[0] is incremented. Function is thread-safe. */ + +void +__gcov_pow2_profiler_atomic (gcov_type *counters, gcov_type value) +{ + if (value == 0 || (value & (value - 1))) + __atomic_fetch_add (&counters[0], 1, MEMMODEL_RELAXED); + else + __atomic_fetch_add (&counters[1], 1, MEMMODEL_RELAXED); +} +#endif + + /* Tries to determine the most common value among its inputs. Checks if the value stored in COUNTERS[0] matches VALUE. If this is the case, COUNTERS[1] is incremented. If this is not the case and COUNTERS[1] is not zero, @@ -68,10 +103,12 @@ __gcov_pow2_profiler (gcov_type *counters, gcov_type value) function is called more than 50% of the time with one value, this value will be in COUNTERS[0] in the end. - In any case, COUNTERS[2] is incremented. */ + In any case, COUNTERS[2] is incremented. If USE_ATOMIC is set to 1, + COUNTERS[2] is updated with an atomic instruction. */ static inline void -__gcov_one_value_profiler_body (gcov_type *counters, gcov_type value) +__gcov_one_value_profiler_body (gcov_type *counters, gcov_type value, + int use_atomic) { if (value == counters[0]) counters[1]++; @@ -82,14 +119,36 @@ __gcov_one_value_profiler_body (gcov_type *counters, gcov_type value) } else counters[1]--; - counters[2]++; + + if (use_atomic) + __atomic_fetch_add (&counters[2], 1, MEMMODEL_RELAXED); + else + counters[2]++; } #ifdef L_gcov_one_value_profiler void __gcov_one_value_profiler (gcov_type *counters, gcov_type value) { - __gcov_one_value_profiler_body (counters, value); + __gcov_one_value_profiler_body (counters, value, 0); +} +#endif + +#ifdef L_gcov_one_value_profiler_atomic + +/* Update one value profilers (COUNTERS) for a given VALUE. + + CAVEAT: Following function is not thread-safe, only total number + of executions (COUNTERS[2]) is update with an atomic instruction. + Problem is that one cannot atomically update two counters + (COUNTERS[0] and COUNTERS[1]), for more information please read + following email thread: + https://gcc.gnu.org/ml/gcc-patches/2016-08/msg00024.html. */ + +void +__gcov_one_value_profiler_atomic (gcov_type *counters, gcov_type value) +{ + __gcov_one_value_profiler_body (counters, value, 1); } #endif @@ -265,7 +324,7 @@ __gcov_indirect_call_profiler_v2 (gcov_type value, void* cur_func) if (cur_func == __gcov_indirect_call_callee || (__LIBGCC_VTABLE_USES_DESCRIPTORS__ && __gcov_indirect_call_callee && *(void **) cur_func == *(void **) __gcov_indirect_call_callee)) - __gcov_one_value_profiler_body (__gcov_indirect_call_counters, value); + __gcov_one_value_profiler_body (__gcov_indirect_call_counters, value, 0); } #endif @@ -282,8 +341,19 @@ __gcov_time_profiler (gcov_type* counters) if (!counters[0]) counters[0] = ++function_counter; } + +/* Sets corresponding COUNTERS if there is no value. + Function is thread-safe. */ + +void +__gcov_time_profiler_atomic (gcov_type* counters) +{ + if (!counters[0]) + counters[0] = __atomic_add_fetch (&function_counter, 1, MEMMODEL_RELAXED); +} #endif + #ifdef L_gcov_average_profiler /* Increase corresponding COUNTER by VALUE. FIXME: Perhaps we want to saturate up. */ @@ -296,6 +366,18 @@ __gcov_average_profiler (gcov_type *counters, gcov_type value) } #endif +#ifdef L_gcov_average_profiler_atomic +/* Increase corresponding COUNTER by VALUE. FIXME: Perhaps we want + to saturate up. Function is thread-safe. */ + +void +__gcov_average_profiler_atomic (gcov_type *counters, gcov_type value) +{ + __atomic_fetch_add (&counters[0], value, MEMMODEL_RELAXED); + __atomic_fetch_add (&counters[1], 1, MEMMODEL_RELAXED); +} +#endif + #ifdef L_gcov_ior_profiler /* Bitwise-OR VALUE into COUNTER. */ @@ -306,4 +388,15 @@ __gcov_ior_profiler (gcov_type *counters, gcov_type value) } #endif +#ifdef L_gcov_ior_profiler_atomic +/* Bitwise-OR VALUE into COUNTER. Function is thread-safe. */ + +void +__gcov_ior_profiler_atomic (gcov_type *counters, gcov_type value) +{ + __atomic_fetch_or (&counters[0], value, MEMMODEL_RELAXED); +} +#endif + + #endif /* inhibit_libc */ diff --git a/libgcc/libgcov.h b/libgcc/libgcov.h index 80f13e26777..25147de2be7 100644 --- a/libgcc/libgcov.h +++ b/libgcc/libgcov.h @@ -268,12 +268,19 @@ extern void __gcov_merge_icall_topn (gcov_type *, unsigned) ATTRIBUTE_HIDDEN; /* The profiler functions. */ extern void __gcov_interval_profiler (gcov_type *, gcov_type, int, unsigned); +extern void __gcov_interval_profiler_atomic (gcov_type *, gcov_type, int, + unsigned); extern void __gcov_pow2_profiler (gcov_type *, gcov_type); +extern void __gcov_pow2_profiler_atomic (gcov_type *, gcov_type); extern void __gcov_one_value_profiler (gcov_type *, gcov_type); +extern void __gcov_one_value_profiler_atomic (gcov_type *, gcov_type); extern void __gcov_indirect_call_profiler_v2 (gcov_type, void *); extern void __gcov_time_profiler (gcov_type *); +extern void __gcov_time_profiler_atomic (gcov_type *); extern void __gcov_average_profiler (gcov_type *, gcov_type); +extern void __gcov_average_profiler_atomic (gcov_type *, gcov_type); extern void __gcov_ior_profiler (gcov_type *, gcov_type); +extern void __gcov_ior_profiler_atomic (gcov_type *, gcov_type); extern void __gcov_indirect_call_topn_profiler (gcov_type, void *); extern void gcov_sort_n_vals (gcov_type *, int); -- 2.30.2