diff options
Diffstat (limited to 'block/blk-cgroup.c')
-rw-r--r-- | block/blk-cgroup.c | 153 |
1 files changed, 68 insertions, 85 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 575d7a2e7203..3c88a79a319b 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -489,10 +489,9 @@ static int blkcg_reset_stats(struct cgroup_subsys_state *css, const char *blkg_dev_name(struct blkcg_gq *blkg) { - /* some drivers (floppy) instantiate a queue w/o disk registered */ - if (blkg->q->backing_dev_info->dev) - return bdi_dev_name(blkg->q->backing_dev_info); - return NULL; + if (!blkg->q->disk || !blkg->q->disk->bdi->dev) + return NULL; + return bdi_dev_name(blkg->q->disk->bdi); } /** @@ -790,6 +789,7 @@ static void blkcg_rstat_flush(struct cgroup_subsys_state *css, int cpu) struct blkcg_gq *parent = blkg->parent; struct blkg_iostat_set *bisc = per_cpu_ptr(blkg->iostat_cpu, cpu); struct blkg_iostat cur, delta; + unsigned long flags; unsigned int seq; /* fetch the current per-cpu values */ @@ -799,21 +799,21 @@ static void blkcg_rstat_flush(struct cgroup_subsys_state *css, int cpu) } while (u64_stats_fetch_retry(&bisc->sync, seq)); /* propagate percpu delta to global */ - u64_stats_update_begin(&blkg->iostat.sync); + flags = u64_stats_update_begin_irqsave(&blkg->iostat.sync); blkg_iostat_set(&delta, &cur); blkg_iostat_sub(&delta, &bisc->last); blkg_iostat_add(&blkg->iostat.cur, &delta); blkg_iostat_add(&bisc->last, &delta); - u64_stats_update_end(&blkg->iostat.sync); + u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags); /* propagate global delta to parent (unless that's root) */ if (parent && parent->parent) { - u64_stats_update_begin(&parent->iostat.sync); + flags = u64_stats_update_begin_irqsave(&parent->iostat.sync); blkg_iostat_set(&delta, &blkg->iostat.cur); blkg_iostat_sub(&delta, &blkg->iostat.last); blkg_iostat_add(&parent->iostat.cur, &delta); blkg_iostat_add(&blkg->iostat.last, &delta); - u64_stats_update_end(&parent->iostat.sync); + u64_stats_update_end_irqrestore(&parent->iostat.sync, flags); } } @@ -848,6 +848,7 @@ static void blkcg_fill_root_iostats(void) 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] += @@ -864,104 +865,86 @@ static void blkcg_fill_root_iostats(void) tmp.bytes[BLKG_IOSTAT_DISCARD] += cpu_dkstats->sectors[STAT_DISCARD] << 9; - u64_stats_update_begin(&blkg->iostat.sync); + flags = u64_stats_update_begin_irqsave(&blkg->iostat.sync); blkg_iostat_set(&blkg->iostat.cur, &tmp); - u64_stats_update_end(&blkg->iostat.sync); + u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags); } } } -static int blkcg_print_stat(struct seq_file *sf, void *v) +static void blkcg_print_one_stat(struct blkcg_gq *blkg, struct seq_file *s) { - struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); - struct blkcg_gq *blkg; - - if (!seq_css(sf)->parent) - blkcg_fill_root_iostats(); - else - cgroup_rstat_flush(blkcg->css.cgroup); - - rcu_read_lock(); - - hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) { - struct blkg_iostat_set *bis = &blkg->iostat; - const char *dname; - char *buf; - u64 rbytes, wbytes, rios, wios, dbytes, dios; - size_t size = seq_get_buf(sf, &buf), off = 0; - int i; - bool has_stats = false; - unsigned seq; + struct blkg_iostat_set *bis = &blkg->iostat; + u64 rbytes, wbytes, rios, wios, dbytes, dios; + bool has_stats = false; + const char *dname; + unsigned seq; + int i; - spin_lock_irq(&blkg->q->queue_lock); + if (!blkg->online) + return; - if (!blkg->online) - goto skip; + dname = blkg_dev_name(blkg); + if (!dname) + return; - dname = blkg_dev_name(blkg); - if (!dname) - goto skip; + seq_printf(s, "%s ", dname); - /* - * Hooray string manipulation, count is the size written NOT - * INCLUDING THE \0, so size is now count+1 less than what we - * had before, but we want to start writing the next bit from - * the \0 so we only add count to buf. - */ - off += scnprintf(buf+off, size-off, "%s ", dname); + do { + seq = u64_stats_fetch_begin(&bis->sync); + + rbytes = bis->cur.bytes[BLKG_IOSTAT_READ]; + wbytes = bis->cur.bytes[BLKG_IOSTAT_WRITE]; + dbytes = bis->cur.bytes[BLKG_IOSTAT_DISCARD]; + rios = bis->cur.ios[BLKG_IOSTAT_READ]; + wios = bis->cur.ios[BLKG_IOSTAT_WRITE]; + dios = bis->cur.ios[BLKG_IOSTAT_DISCARD]; + } while (u64_stats_fetch_retry(&bis->sync, seq)); + + if (rbytes || wbytes || rios || wios) { + has_stats = true; + seq_printf(s, "rbytes=%llu wbytes=%llu rios=%llu wios=%llu dbytes=%llu dios=%llu", + rbytes, wbytes, rios, wios, + dbytes, dios); + } - do { - seq = u64_stats_fetch_begin(&bis->sync); + if (blkcg_debug_stats && atomic_read(&blkg->use_delay)) { + has_stats = true; + seq_printf(s, " use_delay=%d delay_nsec=%llu", + atomic_read(&blkg->use_delay), + atomic64_read(&blkg->delay_nsec)); + } - rbytes = bis->cur.bytes[BLKG_IOSTAT_READ]; - wbytes = bis->cur.bytes[BLKG_IOSTAT_WRITE]; - dbytes = bis->cur.bytes[BLKG_IOSTAT_DISCARD]; - rios = bis->cur.ios[BLKG_IOSTAT_READ]; - wios = bis->cur.ios[BLKG_IOSTAT_WRITE]; - dios = bis->cur.ios[BLKG_IOSTAT_DISCARD]; - } while (u64_stats_fetch_retry(&bis->sync, seq)); + for (i = 0; i < BLKCG_MAX_POLS; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; - if (rbytes || wbytes || rios || wios) { - has_stats = true; - off += scnprintf(buf+off, size-off, - "rbytes=%llu wbytes=%llu rios=%llu wios=%llu dbytes=%llu dios=%llu", - rbytes, wbytes, rios, wios, - dbytes, dios); - } + if (!blkg->pd[i] || !pol->pd_stat_fn) + continue; - if (blkcg_debug_stats && atomic_read(&blkg->use_delay)) { + if (pol->pd_stat_fn(blkg->pd[i], s)) has_stats = true; - off += scnprintf(buf+off, size-off, - " use_delay=%d delay_nsec=%llu", - atomic_read(&blkg->use_delay), - (unsigned long long)atomic64_read(&blkg->delay_nsec)); - } + } - for (i = 0; i < BLKCG_MAX_POLS; i++) { - struct blkcg_policy *pol = blkcg_policy[i]; - size_t written; + if (has_stats) + seq_printf(s, "\n"); +} - if (!blkg->pd[i] || !pol->pd_stat_fn) - continue; +static int blkcg_print_stat(struct seq_file *sf, void *v) +{ + struct blkcg *blkcg = css_to_blkcg(seq_css(sf)); + struct blkcg_gq *blkg; - written = pol->pd_stat_fn(blkg->pd[i], buf+off, size-off); - if (written) - has_stats = true; - off += written; - } + if (!seq_css(sf)->parent) + blkcg_fill_root_iostats(); + else + cgroup_rstat_flush(blkcg->css.cgroup); - if (has_stats) { - if (off < size - 1) { - off += scnprintf(buf+off, size-off, "\n"); - seq_commit(sf, off); - } else { - seq_commit(sf, -1); - } - } - skip: + rcu_read_lock(); + hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) { + spin_lock_irq(&blkg->q->queue_lock); + blkcg_print_one_stat(blkg, sf); spin_unlock_irq(&blkg->q->queue_lock); } - rcu_read_unlock(); return 0; } |