From 5551ff2a7d2d9b1ffcc980244b006b38806ac830 Mon Sep 17 00:00:00 2001 From: Badhri Jagan Sridharan Date: Thu, 13 Oct 2016 16:36:15 -0700 Subject: [PATCH] FROMLIST: binder: change binder_stats to atomics (from https://patchwork.kernel.org/patch/9817755/) Use atomics for stats to avoid needing to lock for increments/decrements Change-Id: I7e29cdab7aaa2dd5516bfe6b6c9926824955a4b3 Signed-off-by: Todd Kjos --- drivers/android/binder.c | 48 +++++++++++++++++++++++----------------- 1 file changed, 28 insertions(+), 20 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 0d473ff84421..a8e56a4c3070 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -166,22 +166,22 @@ enum binder_stat_types { }; struct binder_stats { - int br[_IOC_NR(BR_FAILED_REPLY) + 1]; - int bc[_IOC_NR(BC_REPLY_SG) + 1]; - int obj_created[BINDER_STAT_COUNT]; - int obj_deleted[BINDER_STAT_COUNT]; + atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1]; + atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; + atomic_t obj_created[BINDER_STAT_COUNT]; + atomic_t obj_deleted[BINDER_STAT_COUNT]; }; static struct binder_stats binder_stats; static inline void binder_stats_deleted(enum binder_stat_types type) { - binder_stats.obj_deleted[type]++; + atomic_inc(&binder_stats.obj_deleted[type]); } static inline void binder_stats_created(enum binder_stat_types type) { - binder_stats.obj_created[type]++; + atomic_inc(&binder_stats.obj_created[type]); } struct binder_transaction_log_entry { @@ -1825,9 +1825,9 @@ static int binder_thread_write(struct binder_proc *proc, ptr += sizeof(uint32_t); trace_binder_command(cmd); if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) { - binder_stats.bc[_IOC_NR(cmd)]++; - proc->stats.bc[_IOC_NR(cmd)]++; - thread->stats.bc[_IOC_NR(cmd)]++; + atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]); } switch (cmd) { case BC_INCREFS: @@ -2201,9 +2201,9 @@ static void binder_stat_br(struct binder_proc *proc, { trace_binder_return(cmd); if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) { - binder_stats.br[_IOC_NR(cmd)]++; - proc->stats.br[_IOC_NR(cmd)]++; - thread->stats.br[_IOC_NR(cmd)]++; + atomic_inc(&binder_stats.br[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.br[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.br[_IOC_NR(cmd)]); } } @@ -3453,17 +3453,21 @@ static void print_binder_stats(struct seq_file *m, const char *prefix, BUILD_BUG_ON(ARRAY_SIZE(stats->bc) != ARRAY_SIZE(binder_command_strings)); for (i = 0; i < ARRAY_SIZE(stats->bc); i++) { - if (stats->bc[i]) + int temp = atomic_read(&stats->bc[i]); + + if (temp) seq_printf(m, "%s%s: %d\n", prefix, - binder_command_strings[i], stats->bc[i]); + binder_command_strings[i], temp); } BUILD_BUG_ON(ARRAY_SIZE(stats->br) != ARRAY_SIZE(binder_return_strings)); for (i = 0; i < ARRAY_SIZE(stats->br); i++) { - if (stats->br[i]) + int temp = atomic_read(&stats->br[i]); + + if (temp) seq_printf(m, "%s%s: %d\n", prefix, - binder_return_strings[i], stats->br[i]); + binder_return_strings[i], temp); } BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != @@ -3471,11 +3475,15 @@ static void print_binder_stats(struct seq_file *m, const char *prefix, BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != ARRAY_SIZE(stats->obj_deleted)); for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) { - if (stats->obj_created[i] || stats->obj_deleted[i]) - seq_printf(m, "%s%s: active %d total %d\n", prefix, + int created = atomic_read(&stats->obj_created[i]); + int deleted = atomic_read(&stats->obj_deleted[i]); + + if (created || deleted) + seq_printf(m, "%s%s: active %d total %d\n", + prefix, binder_objstat_strings[i], - stats->obj_created[i] - stats->obj_deleted[i], - stats->obj_created[i]); + created - deleted, + created); } } -- 2.20.1