From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from merlin.infradead.org ([205.233.59.134]:33400 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754572AbdJRMAQ (ORCPT ); Wed, 18 Oct 2017 08:00:16 -0400 Received: from [216.160.245.99] (helo=kernel.dk) by merlin.infradead.org with esmtpsa (Exim 4.87 #1 (Red Hat Linux)) id 1e4n1D-0006IU-Mt for fio@vger.kernel.org; Wed, 18 Oct 2017 12:00:15 +0000 Subject: Recent changes (master) From: Jens Axboe Message-Id: <20171018120002.8BAA42C234E@kernel.dk> Date: Wed, 18 Oct 2017 06:00:02 -0600 (MDT) Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: fio@vger.kernel.org The following changes since commit c13a60ce72aaf5b07b93977ab86e7522d167ec28: flow: fix bad overflowing math (2017-10-12 10:54:27 -0600) are available in the git repository at: git://git.kernel.dk/fio.git master for you to fetch changes up to 7ad86b642b6c3962177064b85b4c055ae9455032: Merge branch 'cpuclock-test' (2017-10-17 12:59:40 -0600) ---------------------------------------------------------------- Jens Axboe (2): gettime: improve cpu clock test Merge branch 'cpuclock-test' configure | 46 ++++++++++++++++++++++++++++++++++++++++++++++ gettime.c | 21 ++++++++++++--------- 2 files changed, 58 insertions(+), 9 deletions(-) --- Diff of recent changes: diff --git a/configure b/configure index 2b46ab8..d34c000 100755 --- a/configure +++ b/configure @@ -343,6 +343,8 @@ CYGWIN*) # Flags below are still necessary mostly for MinGW. socklen_t="yes" sfaa="yes" + sync_sync="yes" + cmp_swap="yes" rusage_thread="yes" fdatasync="yes" clock_gettime="yes" # clock_monotonic probe has dependency on this @@ -707,6 +709,44 @@ fi print_config "__sync_fetch_and_add" "$sfaa" ########################################## +# __sync_synchronize() test +if test "$sync_sync" != "yes" ; then + sync_sync="no" +fi +cat > $TMPC << EOF +#include + +int main(int argc, char **argv) +{ + __sync_synchronize(); + return 0; +} +EOF +if compile_prog "" "" "__sync_synchronize()" ; then + sync_sync="yes" +fi +print_config "__sync_synchronize" "$sync_sync" + +########################################## +# __sync_val_compare_and_swap() test +if test "$cmp_swap" != "yes" ; then + cmp_swap="no" +fi +cat > $TMPC << EOF +#include + +int main(int argc, char **argv) +{ + int x = 0; + return __sync_val_compare_and_swap(&x, 1, 2); +} +EOF +if compile_prog "" "" "__sync_val_compare_and_swap()" ; then + cmp_swap="yes" +fi +print_config "__sync_val_compare_and_swap" "$cmp_swap" + +########################################## # libverbs probe if test "$libverbs" != "yes" ; then libverbs="no" @@ -2108,6 +2148,12 @@ fi if test "$sfaa" = "yes" ; then output_sym "CONFIG_SFAA" fi +if test "$sync_sync" = "yes" ; then + output_sym "CONFIG_SYNC_SYNC" +fi +if test "$cmp_swap" = "yes" ; then + output_sym "CONFIG_CMP_SWAP" +fi if test "$libverbs" = "yes" -a "$rdmacm" = "yes" ; then output_sym "CONFIG_RDMA" fi diff --git a/gettime.c b/gettime.c index 1cbef84..c256a96 100644 --- a/gettime.c +++ b/gettime.c @@ -548,7 +548,7 @@ uint64_t time_since_now(const struct timespec *s) } #if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) && \ - defined(CONFIG_SFAA) + defined(CONFIG_SYNC_SYNC) && defined(CONFIG_CMP_SWAP) #define CLOCK_ENTRIES_DEBUG 100000 #define CLOCK_ENTRIES_TEST 1000 @@ -570,9 +570,10 @@ struct clock_thread { struct clock_entry *entries; }; -static inline uint32_t atomic32_inc_return(uint32_t *seq) +static inline uint32_t atomic32_compare_and_swap(uint32_t *ptr, uint32_t old, + uint32_t new) { - return 1 + __sync_fetch_and_add(seq, 1); + return __sync_val_compare_and_swap(ptr, old, new); } static void *clock_thread_fn(void *data) @@ -580,7 +581,6 @@ static void *clock_thread_fn(void *data) struct clock_thread *t = data; struct clock_entry *c; os_cpu_mask_t cpu_mask; - uint32_t last_seq; unsigned long long first; int i; @@ -604,7 +604,6 @@ static void *clock_thread_fn(void *data) pthread_mutex_unlock(&t->started); first = get_cpu_clock(); - last_seq = 0; c = &t->entries[0]; for (i = 0; i < t->nr_entries; i++, c++) { uint32_t seq; @@ -612,11 +611,15 @@ static void *clock_thread_fn(void *data) c->cpu = t->cpu; do { - seq = atomic32_inc_return(t->seq); - if (seq < last_seq) + seq = *t->seq; + if (seq == UINT_MAX) break; + __sync_synchronize(); tsc = get_cpu_clock(); - } while (seq != *t->seq); + } while (seq != atomic32_compare_and_swap(t->seq, seq, seq + 1)); + + if (seq == UINT_MAX) + break; c->seq = seq; c->tsc = tsc; @@ -634,7 +637,7 @@ static void *clock_thread_fn(void *data) * The most common platform clock breakage is returning zero * indefinitely. Check for that and return failure. */ - if (!t->entries[i - 1].tsc && !t->entries[0].tsc) + if (i > 1 && !t->entries[i - 1].tsc && !t->entries[0].tsc) goto err; fio_cpuset_exit(&cpu_mask);