From: Chengming Zhou zhouchengming@bytedance.com
[ Upstream commit f122d103b564e5fb7c82de902c6f8f6cbdf50ec9 ]
Don't need to do blkg_iostat_set for top blkg iostat on each CPU, so move it after percpu stat aggregation.
Fixes: ef45fe470e1e ("blk-cgroup: show global disk stats in root cgroup io.stat") Signed-off-by: Chengming Zhou zhouchengming@bytedance.com Acked-by: Tejun Heo tj@kernel.org Link: https://lore.kernel.org/r/20220213085902.88884-1-zhouchengming@bytedance.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-cgroup.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 663aabfeba18..f896f4982665 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -856,11 +856,11 @@ static void blkcg_fill_root_iostats(void) blk_queue_root_blkg(bdev_get_queue(bdev)); struct blkg_iostat tmp; int cpu; + unsigned long flags;
memset(&tmp, 0, sizeof(tmp)); for_each_possible_cpu(cpu) { struct disk_stats *cpu_dkstats; - unsigned long flags;
cpu_dkstats = per_cpu_ptr(bdev->bd_stats, cpu); tmp.ios[BLKG_IOSTAT_READ] += @@ -876,11 +876,11 @@ static void blkcg_fill_root_iostats(void) cpu_dkstats->sectors[STAT_WRITE] << 9; tmp.bytes[BLKG_IOSTAT_DISCARD] += cpu_dkstats->sectors[STAT_DISCARD] << 9; - - flags = u64_stats_update_begin_irqsave(&blkg->iostat.sync); - blkg_iostat_set(&blkg->iostat.cur, &tmp); - u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags); } + + flags = u64_stats_update_begin_irqsave(&blkg->iostat.sync); + blkg_iostat_set(&blkg->iostat.cur, &tmp); + u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags); } }