diff options
| -rw-r--r-- | block/blk-cgroup.c | 27 | ||||
| -rw-r--r-- | block/blk-cgroup.h | 2 |
2 files changed, 24 insertions, 5 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 34bfcefdd924..3622518e1c23 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -400,14 +400,25 @@ void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes, bool direction, bool sync) { struct blkio_group_stats_cpu *stats_cpu; + unsigned long flags; + + /* + * Disabling interrupts to provide mutual exclusion between two + * writes on same cpu. It probably is not needed for 64bit. Not + * optimizing that case yet. + */ + local_irq_save(flags); stats_cpu = this_cpu_ptr(blkg->stats_cpu); + u64_stats_update_begin(&stats_cpu->syncp); stats_cpu->sectors += bytes >> 9; blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICED], 1, direction, sync); blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_SERVICE_BYTES], bytes, direction, sync); + u64_stats_update_end(&stats_cpu->syncp); + local_irq_restore(flags); } EXPORT_SYMBOL_GPL(blkiocg_update_dispatch_stats); @@ -622,15 +633,21 @@ static uint64_t blkio_read_stat_cpu(struct blkio_group *blkg, { int cpu; struct blkio_group_stats_cpu *stats_cpu; - uint64_t val = 0; + u64 val = 0, tval; for_each_possible_cpu(cpu) { + unsigned int start; stats_cpu = per_cpu_ptr(blkg->stats_cpu, cpu); - if (type == BLKIO_STAT_CPU_SECTORS) - val += stats_cpu->sectors; - else - val += stats_cpu->stat_arr_cpu[type][sub_type]; + do { + start = u64_stats_fetch_begin(&stats_cpu->syncp); + if (type == BLKIO_STAT_CPU_SECTORS) + tval = stats_cpu->sectors; + else + tval = stats_cpu->stat_arr_cpu[type][sub_type]; + } while(u64_stats_fetch_retry(&stats_cpu->syncp, start)); + + val += tval; } return val; diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index fd730a24b491..262226798093 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -14,6 +14,7 @@ */ #include <linux/cgroup.h> +#include <linux/u64_stats_sync.h> enum blkio_policy_id { BLKIO_POLICY_PROP = 0, /* Proportional Bandwidth division */ @@ -154,6 +155,7 @@ struct blkio_group_stats { struct blkio_group_stats_cpu { uint64_t sectors; uint64_t stat_arr_cpu[BLKIO_STAT_CPU_NR][BLKIO_STAT_TOTAL]; + struct u64_stats_sync syncp; }; struct blkio_group { |