Just like the blk_mq_ctx counterparts, we've got a bunch of counters
in here that are only for debugfs and are of questionnable value. They
are:
- dispatched, index of how many requests were dispatched in one go
- poll_{considered,invoked,success}, which track poll sucess rates. We're
confident in the iopoll implementation at this point, don't bother
tracking these.
As a bonus, this shrinks each hardware queue from 576 bytes to 512 bytes,
dropping a whole cacheline.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
block/blk-mq-debugfs.c | 67 ------------------------------------------
block/blk-mq.c | 16 ----------
include/linux/blk-mq.h | 10 -------
3 files changed, 93 deletions(-)
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 928a16af9175..68ca5d21cda7 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -529,70 +529,6 @@ static int hctx_sched_tags_bitmap_show(void *data, struct seq_file *m)
return res;
}
-static int hctx_io_poll_show(void *data, struct seq_file *m)
-{
- struct blk_mq_hw_ctx *hctx = data;
-
- seq_printf(m, "considered=%lu\n", hctx->poll_considered);
- seq_printf(m, "invoked=%lu\n", hctx->poll_invoked);
- seq_printf(m, "success=%lu\n", hctx->poll_success);
- return 0;
-}
-
-static ssize_t hctx_io_poll_write(void *data, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct blk_mq_hw_ctx *hctx = data;
-
- hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
- return count;
-}
-
-static int hctx_dispatched_show(void *data, struct seq_file *m)
-{
- struct blk_mq_hw_ctx *hctx = data;
- int i;
-
- seq_printf(m, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
-
- for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
- unsigned int d = 1U << (i - 1);
-
- seq_printf(m, "%8u\t%lu\n", d, hctx->dispatched[i]);
- }
-
- seq_printf(m, "%8u+\t%lu\n", 1U << (i - 1), hctx->dispatched[i]);
- return 0;
-}
-
-static ssize_t hctx_dispatched_write(void *data, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct blk_mq_hw_ctx *hctx = data;
- int i;
-
- for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
- hctx->dispatched[i] = 0;
- return count;
-}
-
-static int hctx_queued_show(void *data, struct seq_file *m)
-{
- struct blk_mq_hw_ctx *hctx = data;
-
- seq_printf(m, "%lu\n", hctx->queued);
- return 0;
-}
-
-static ssize_t hctx_queued_write(void *data, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct blk_mq_hw_ctx *hctx = data;
-
- hctx->queued = 0;
- return count;
-}
-
static int hctx_run_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
@@ -738,9 +674,6 @@ static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
{"tags_bitmap", 0400, hctx_tags_bitmap_show},
{"sched_tags", 0400, hctx_sched_tags_show},
{"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show},
- {"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write},
- {"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write},
- {"queued", 0600, hctx_queued_show, hctx_queued_write},
{"run", 0600, hctx_run_show, hctx_run_write},
{"active", 0400, hctx_active_show},
{"dispatch_busy", 0400, hctx_dispatch_busy_show},
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4d91b74ce67a..2197cfbf081f 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -316,7 +316,6 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
rq->mq_ctx = ctx;
rq->mq_hctx = hctx;
rq->cmd_flags = cmd_flags;
- data->hctx->queued++;
if (!q->elevator) {
rq->rq_flags = 0;
rq->tag = tag;
@@ -1268,14 +1267,6 @@ struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
return data.rq;
}
-static inline unsigned int queued_to_index(unsigned int queued)
-{
- if (!queued)
- return 0;
-
- return min(BLK_MQ_MAX_DISPATCH_ORDER - 1, ilog2(queued) + 1);
-}
-
static bool __blk_mq_alloc_driver_tag(struct request *rq)
{
struct sbitmap_queue *bt = &rq->mq_hctx->tags->bitmap_tags;
@@ -1597,8 +1588,6 @@ bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *list,
if (!list_empty(&zone_list))
list_splice_tail_init(&zone_list, list);
- hctx->dispatched[queued_to_index(queued)]++;
-
/* If we didn't flush the entire list, we could have told the driver
* there was more coming, but that turned out to be a lie.
*/
@@ -4212,14 +4201,9 @@ static int blk_mq_poll_classic(struct request_queue *q, blk_qc_t cookie,
long state = get_current_state();
int ret;
- hctx->poll_considered++;
-
do {
- hctx->poll_invoked++;
-
ret = q->mq_ops->poll(hctx);
if (ret > 0) {
- hctx->poll_success++;
__set_current_state(TASK_RUNNING);
return ret;
}
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 1dccea9505e5..9fc868abcc81 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -341,9 +341,6 @@ struct blk_mq_hw_ctx {
unsigned long queued;
/** @run: Number of dispatched requests. */
unsigned long run;
-#define BLK_MQ_MAX_DISPATCH_ORDER 7
- /** @dispatched: Number of dispatch requests by queue. */
- unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER];
/** @numa_node: NUMA node the storage adapter has been connected to. */
unsigned int numa_node;
@@ -363,13 +360,6 @@ struct blk_mq_hw_ctx {
/** @kobj: Kernel object for sysfs. */
struct kobject kobj;
- /** @poll_considered: Count times blk_mq_poll() was called. */
- unsigned long poll_considered;
- /** @poll_invoked: Count how many requests blk_mq_poll() polled. */
- unsigned long poll_invoked;
- /** @poll_success: Count how many polled requests were completed. */
- unsigned long poll_success;
-
#ifdef CONFIG_BLK_DEBUG_FS
/**
* @debugfs_dir: debugfs directory for this hardware queue. Named
--
2.33.1
