diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-core.c | 84 | ||||
| -rw-r--r-- | block/genhd.c | 17 | ||||
| -rw-r--r-- | block/partition-generic.c | 11 |
3 files changed, 112 insertions, 0 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 119658534dfd..323cc15b155a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -40,6 +40,8 @@ #include "blk.h" #include "blk-mq.h" +#include <linux/math64.h> + EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap); EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap); EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete); @@ -3563,3 +3565,85 @@ int __init blk_dev_init(void) return 0; } + +/* + * Blk IO latency support. We want this to be as cheap as possible, so doing + * this lockless (and avoiding atomics), a few off by a few errors in this + * code is not harmful, and we don't want to do anything that is + * perf-impactful. + * TODO : If necessary, we can make the histograms per-cpu and aggregate + * them when printing them out. + */ +void +blk_zero_latency_hist(struct io_latency_state *s) +{ + memset(s->latency_y_axis_read, 0, + sizeof(s->latency_y_axis_read)); + memset(s->latency_y_axis_write, 0, + sizeof(s->latency_y_axis_write)); + s->latency_reads_elems = 0; + s->latency_writes_elems = 0; +} +EXPORT_SYMBOL(blk_zero_latency_hist); + +ssize_t +blk_latency_hist_show(struct io_latency_state *s, char *buf) +{ + int i; + int bytes_written = 0; + u_int64_t num_elem, elem; + int pct; + + num_elem = s->latency_reads_elems; + if (num_elem > 0) { + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "IO svc_time Read Latency Histogram (n = %llu):\n", + num_elem); + for (i = 0; + i < ARRAY_SIZE(latency_x_axis_us); + i++) { + elem = s->latency_y_axis_read[i]; + pct = div64_u64(elem * 100, num_elem); + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "\t< %5lluus%15llu%15d%%\n", + latency_x_axis_us[i], + elem, pct); + } + /* Last element in y-axis table is overflow */ + elem = s->latency_y_axis_read[i]; + pct = div64_u64(elem * 100, num_elem); + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "\t> %5dms%15llu%15d%%\n", 10, + elem, pct); + } + num_elem = s->latency_writes_elems; + if (num_elem > 0) { + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "IO svc_time Write Latency Histogram (n = %llu):\n", + num_elem); + for (i = 0; + i < ARRAY_SIZE(latency_x_axis_us); + i++) { + elem = s->latency_y_axis_write[i]; + pct = div64_u64(elem * 100, num_elem); + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "\t< %5lluus%15llu%15d%%\n", + latency_x_axis_us[i], + elem, pct); + } + /* Last element in y-axis table is overflow */ + elem = s->latency_y_axis_write[i]; + pct = div64_u64(elem * 100, num_elem); + bytes_written += scnprintf(buf + bytes_written, + PAGE_SIZE - bytes_written, + "\t> %5dms%15llu%15d%%\n", 10, + elem, pct); + } + return bytes_written; +} +EXPORT_SYMBOL(blk_latency_hist_show); diff --git a/block/genhd.c b/block/genhd.c index 3032453a89e6..a87e77626504 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1117,6 +1117,22 @@ static void disk_release(struct device *dev) blk_put_queue(disk->queue); kfree(disk); } + +static int disk_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct gendisk *disk = dev_to_disk(dev); + struct disk_part_iter piter; + struct hd_struct *part; + int cnt = 0; + + disk_part_iter_init(&piter, disk, 0); + while((part = disk_part_iter_next(&piter))) + cnt++; + disk_part_iter_exit(&piter); + add_uevent_var(env, "NPARTS=%u", cnt); + return 0; +} + struct class block_class = { .name = "block", }; @@ -1136,6 +1152,7 @@ static struct device_type disk_type = { .groups = disk_attr_groups, .release = disk_release, .devnode = block_devnode, + .uevent = disk_uevent, }; #ifdef CONFIG_PROC_FS diff --git a/block/partition-generic.c b/block/partition-generic.c index 3c062699f28b..19cf33b91a5a 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -216,10 +216,21 @@ static void part_release(struct device *dev) kfree(p); } +static int part_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct hd_struct *part = dev_to_part(dev); + + add_uevent_var(env, "PARTN=%u", part->partno); + if (part->info && part->info->volname[0]) + add_uevent_var(env, "PARTNAME=%s", part->info->volname); + return 0; +} + struct device_type part_type = { .name = "partition", .groups = part_attr_groups, .release = part_release, + .uevent = part_uevent, }; static void delete_partition_rcu_cb(struct rcu_head *head) |