diff options
Diffstat (limited to 'block/blk-stat.c')
| -rw-r--r-- | block/blk-stat.c | 221 |
1 files changed, 0 insertions, 221 deletions
diff --git a/block/blk-stat.c b/block/blk-stat.c deleted file mode 100644 index bdb16d84b..000000000 --- a/block/blk-stat.c +++ /dev/null @@ -1,221 +0,0 @@ -/* - * Block stat tracking code - * - * Copyright (C) 2016 Jens Axboe - */ -#include <linux/kernel.h> -#include <linux/blk-mq.h> - -#include "blk-stat.h" -#include "blk-mq.h" - -static void blk_stat_flush_batch(struct blk_rq_stat *stat) -{ - if (!stat->nr_batch) - return; - if (!stat->nr_samples) - stat->mean = div64_s64(stat->batch, stat->nr_batch); - else { - stat->mean = div64_s64((stat->mean * stat->nr_samples) + - stat->batch, - stat->nr_samples + stat->nr_batch); - } - - stat->nr_samples += stat->nr_batch; - stat->nr_batch = stat->batch = 0; -} - -void blk_stat_sum(struct blk_rq_stat *dst, struct blk_rq_stat *src) -{ - if (!src->nr_samples) - return; - - blk_stat_flush_batch(src); - - dst->min = min(dst->min, src->min); - dst->max = max(dst->max, src->max); - - if (!dst->nr_samples) - dst->mean = src->mean; - else { - dst->mean = div64_s64((src->mean * src->nr_samples) + - (dst->mean * dst->nr_samples), - dst->nr_samples + src->nr_samples); - } - dst->nr_samples += src->nr_samples; -} - -static void blk_mq_stat_get(struct request_queue *q, struct blk_rq_stat *dst) -{ - struct blk_mq_hw_ctx *hctx; - struct blk_mq_ctx *ctx; - uint64_t latest = 0; - int i, j, nr; - - blk_stat_init(&dst[0]); - blk_stat_init(&dst[1]); - - nr = 0; - do { - uint64_t newest = 0; - - queue_for_each_hw_ctx(q, hctx, i) { - hctx_for_each_ctx(hctx, ctx, j) { - if (!ctx->stat[0].nr_samples && - !ctx->stat[1].nr_samples) - continue; - if (ctx->stat[0].time > newest) - newest = ctx->stat[0].time; - if (ctx->stat[1].time > newest) - newest = ctx->stat[1].time; - } - } - - /* - * No samples - */ - if (!newest) - break; - - if (newest > latest) - latest = newest; - - queue_for_each_hw_ctx(q, hctx, i) { - hctx_for_each_ctx(hctx, ctx, j) { - if (ctx->stat[0].time == newest) { - blk_stat_sum(&dst[0], &ctx->stat[0]); - nr++; - } - if (ctx->stat[1].time == newest) { - blk_stat_sum(&dst[1], &ctx->stat[1]); - nr++; - } - } - } - /* - * If we race on finding an entry, just loop back again. - * Should be very rare. - */ - } while (!nr); - - dst[0].time = dst[1].time = latest; -} - -void blk_queue_stat_get(struct request_queue *q, struct blk_rq_stat *dst) -{ - if (q->mq_ops) - blk_mq_stat_get(q, dst); - else { - memcpy(&dst[0], &q->rq_stats[0], sizeof(struct blk_rq_stat)); - memcpy(&dst[1], &q->rq_stats[1], sizeof(struct blk_rq_stat)); - } -} - -void blk_hctx_stat_get(struct blk_mq_hw_ctx *hctx, struct blk_rq_stat *dst) -{ - struct blk_mq_ctx *ctx; - unsigned int i, nr; - - nr = 0; - do { - uint64_t newest = 0; - - hctx_for_each_ctx(hctx, ctx, i) { - if (!ctx->stat[0].nr_samples && - !ctx->stat[1].nr_samples) - continue; - - if (ctx->stat[0].time > newest) - newest = ctx->stat[0].time; - if (ctx->stat[1].time > newest) - newest = ctx->stat[1].time; - } - - if (!newest) - break; - - hctx_for_each_ctx(hctx, ctx, i) { - if (ctx->stat[0].time == newest) { - blk_stat_sum(&dst[0], &ctx->stat[0]); - nr++; - } - if (ctx->stat[1].time == newest) { - blk_stat_sum(&dst[1], &ctx->stat[1]); - nr++; - } - } - /* - * If we race on finding an entry, just loop back again. - * Should be very rare, as the window is only updated - * occasionally - */ - } while (!nr); -} - -static void __blk_stat_init(struct blk_rq_stat *stat, s64 time_now) -{ - stat->min = -1ULL; - stat->max = stat->nr_samples = stat->mean = 0; - stat->batch = stat->nr_batch = 0; - stat->time = time_now & BLK_STAT_MASK; -} - -void blk_stat_init(struct blk_rq_stat *stat) -{ - __blk_stat_init(stat, ktime_to_ns(ktime_get())); -} - -static bool __blk_stat_is_current(struct blk_rq_stat *stat, s64 now) -{ - return (now & BLK_STAT_MASK) == (stat->time & BLK_STAT_MASK); -} - -bool blk_stat_is_current(struct blk_rq_stat *stat) -{ - return __blk_stat_is_current(stat, ktime_to_ns(ktime_get())); -} - -void blk_stat_add(struct blk_rq_stat *stat, struct request *rq) -{ - s64 now, value; - u64 rq_time = wbt_issue_stat_get_time(&rq->wb_stat); - - now = ktime_to_ns(ktime_get()); - if (now < rq_time) - return; - - if (!__blk_stat_is_current(stat, now)) - __blk_stat_init(stat, now); - - value = now - rq_time; - if (value > stat->max) - stat->max = value; - if (value < stat->min) - stat->min = value; - - if (stat->batch + value < stat->batch || - stat->nr_batch + 1 == BLK_RQ_STAT_BATCH) - blk_stat_flush_batch(stat); - - stat->batch += value; - stat->nr_batch++; -} - -void blk_stat_clear(struct request_queue *q) -{ - if (q->mq_ops) { - struct blk_mq_hw_ctx *hctx; - struct blk_mq_ctx *ctx; - int i, j; - - queue_for_each_hw_ctx(q, hctx, i) { - hctx_for_each_ctx(hctx, ctx, j) { - blk_stat_init(&ctx->stat[0]); - blk_stat_init(&ctx->stat[1]); - } - } - } else { - blk_stat_init(&q->rq_stats[0]); - blk_stat_init(&q->rq_stats[1]); - } -} |