| Message ID | 1474850480-1667-1-git-send-email-sbates@raithlin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi All Apologies. That was the wrong patch. Please ignore. Cheers Stephen > On Sep 25, 2016, at 6:41 PM, Stephen Bates <sbates@raithlin.com> wrote: > > In order to help determine the effectiveness of polling in a running > system it is usful to determine the ratio of how often the poll > function is called vs how often the completion is checked. For this > reason we add a poll_considered variable and add it to the sysfs entry > for io_poll. > > Signed-off-by: Stephen Bates <sbates@raithlin.com> > --- > block/blk-core.c | 8 ++++++-- > block/blk-mq-sysfs.c | 4 +++- > include/linux/blk-mq.h | 1 + > 3 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/block/blk-core.c b/block/blk-core.c > index 34ff808..14d7c07 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -3307,19 +3307,23 @@ bool blk_poll(struct request_queue *q, blk_qc_t cookie) > { > struct blk_plug *plug; > long state; > + unsigned int queue_num; > + struct blk_mq_hw_ctx *hctx; > > if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) || > !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) > return false; > > + queue_num = blk_qc_t_to_queue_num(cookie); > + hctx = q->queue_hw_ctx[queue_num]; > + hctx->poll_considered++; > + > plug = current->plug; > if (plug) > blk_flush_plug_list(plug, false); > > state = current->state; > while (!need_resched()) { > - unsigned int queue_num = blk_qc_t_to_queue_num(cookie); > - struct blk_mq_hw_ctx *hctx = q->queue_hw_ctx[queue_num]; > int ret; > > hctx->poll_invoked++; > diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c > index fe822aa..ea8c3f5 100644 > --- a/block/blk-mq-sysfs.c > +++ b/block/blk-mq-sysfs.c > @@ -176,7 +176,9 @@ static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page) > > static ssize_t blk_mq_hw_sysfs_poll_show(struct blk_mq_hw_ctx *hctx, char *page) > { > - return sprintf(page, "invoked=%lu, success=%lu\n", hctx->poll_invoked, hctx->poll_success); > + return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n", > + hctx->poll_considered, hctx->poll_invoked, > + hctx->poll_success); > } > > static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx, > diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h > index e1544f0..7710f79 100644 > --- a/include/linux/blk-mq.h > +++ b/include/linux/blk-mq.h > @@ -61,6 +61,7 @@ struct blk_mq_hw_ctx { > struct blk_mq_cpu_notifier cpu_notifier; > struct kobject kobj; > > + unsigned long poll_considered; > unsigned long poll_invoked; > unsigned long poll_success; > }; > -- > 2.5.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/block/blk-core.c b/block/blk-core.c index 34ff808..14d7c07 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -3307,19 +3307,23 @@ bool blk_poll(struct request_queue *q, blk_qc_t cookie) { struct blk_plug *plug; long state; + unsigned int queue_num; + struct blk_mq_hw_ctx *hctx; if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) || !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) return false; + queue_num = blk_qc_t_to_queue_num(cookie); + hctx = q->queue_hw_ctx[queue_num]; + hctx->poll_considered++; + plug = current->plug; if (plug) blk_flush_plug_list(plug, false); state = current->state; while (!need_resched()) { - unsigned int queue_num = blk_qc_t_to_queue_num(cookie); - struct blk_mq_hw_ctx *hctx = q->queue_hw_ctx[queue_num]; int ret; hctx->poll_invoked++; diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c index fe822aa..ea8c3f5 100644 --- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -176,7 +176,9 @@ static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page) static ssize_t blk_mq_hw_sysfs_poll_show(struct blk_mq_hw_ctx *hctx, char *page) { - return sprintf(page, "invoked=%lu, success=%lu\n", hctx->poll_invoked, hctx->poll_success); + return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n", + hctx->poll_considered, hctx->poll_invoked, + hctx->poll_success); } static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx, diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index e1544f0..7710f79 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -61,6 +61,7 @@ struct blk_mq_hw_ctx { struct blk_mq_cpu_notifier cpu_notifier; struct kobject kobj; + unsigned long poll_considered; unsigned long poll_invoked; unsigned long poll_success; };
In order to help determine the effectiveness of polling in a running system it is usful to determine the ratio of how often the poll function is called vs how often the completion is checked. For this reason we add a poll_considered variable and add it to the sysfs entry for io_poll. Signed-off-by: Stephen Bates <sbates@raithlin.com> --- block/blk-core.c | 8 ++++++-- block/blk-mq-sysfs.c | 4 +++- include/linux/blk-mq.h | 1 + 3 files changed, 10 insertions(+), 3 deletions(-)