| Message ID | 20190318144441.133569-1-yuyufen@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] block: add BLK_MQ_POLL_CLASSIC for hybrid poll and return EINVAL for unexpected value | expand |
On 2019/03/18 23:40, Yufen Yu wrote: > For q->poll_nsec == -1, means doing classic poll, not hybrid poll. > We introduce a new flag BLK_MQ_POLL_CLASSIC to replace -1, which > may make code much easier to read. > > Additionally, since val is an int obtained with kstrtoint(), val can be > a negative value other than -1, so return -EINVAL for that case. > > Thanks to Damien Le Moal for some good suggestion. > > Signed-off-by: Yufen Yu <yuyufen@huawei.com> > --- > block/blk-mq.c | 4 ++-- > block/blk-sysfs.c | 12 +++++++----- > include/linux/blkdev.h | 3 +++ > 3 files changed, 12 insertions(+), 7 deletions(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index a9c181603cbd..1c588e5c4a02 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -2857,7 +2857,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, > /* > * Default to classic polling > */ > - q->poll_nsec = -1; > + q->poll_nsec = BLK_MQ_POLL_CLASSIC; > > blk_mq_init_cpu_queues(q, set->nr_hw_queues); > blk_mq_add_queue_tag_set(set, q); > @@ -3392,7 +3392,7 @@ static bool blk_mq_poll_hybrid(struct request_queue *q, > { > struct request *rq; > > - if (q->poll_nsec == -1) > + if (q->poll_nsec == BLK_MQ_POLL_CLASSIC) > return false; > > if (!blk_qc_t_is_internal(cookie)) > diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c > index 59685918167e..422327089e0f 100644 > --- a/block/blk-sysfs.c > +++ b/block/blk-sysfs.c > @@ -360,8 +360,8 @@ static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) > { > int val; > > - if (q->poll_nsec == -1) > - val = -1; > + if (q->poll_nsec == BLK_MQ_POLL_CLASSIC) > + val = BLK_MQ_POLL_CLASSIC; > else > val = q->poll_nsec / 1000; > > @@ -380,10 +380,12 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, > if (err < 0) > return err; > > - if (val == -1) > - q->poll_nsec = -1; > - else > + if (val == BLK_MQ_POLL_CLASSIC) > + q->poll_nsec = BLK_MQ_POLL_CLASSIC; > + else if (val >= 0) > q->poll_nsec = val * 1000; > + else > + return -EINVAL; > > return count; > } > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index 0de92b29f589..5c58a3b2bf00 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -50,6 +50,9 @@ struct blk_stat_callback; > /* Must be consistent with blk_mq_poll_stats_bkt() */ > #define BLK_MQ_POLL_STATS_BKTS 16 > > +/* Doing classic polling */ > +#define BLK_MQ_POLL_CLASSIC -1 > + > /* > * Maximum number of blkcg policies allowed to be registered concurrently. > * Defined here to simplify include dependency. > Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
On 3/18/19 8:44 AM, Yufen Yu wrote: > For q->poll_nsec == -1, means doing classic poll, not hybrid poll. > We introduce a new flag BLK_MQ_POLL_CLASSIC to replace -1, which > may make code much easier to read. > > Additionally, since val is an int obtained with kstrtoint(), val can be > a negative value other than -1, so return -EINVAL for that case. Applied, thanks.
diff --git a/block/blk-mq.c b/block/blk-mq.c index a9c181603cbd..1c588e5c4a02 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2857,7 +2857,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, /* * Default to classic polling */ - q->poll_nsec = -1; + q->poll_nsec = BLK_MQ_POLL_CLASSIC; blk_mq_init_cpu_queues(q, set->nr_hw_queues); blk_mq_add_queue_tag_set(set, q); @@ -3392,7 +3392,7 @@ static bool blk_mq_poll_hybrid(struct request_queue *q, { struct request *rq; - if (q->poll_nsec == -1) + if (q->poll_nsec == BLK_MQ_POLL_CLASSIC) return false; if (!blk_qc_t_is_internal(cookie)) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 59685918167e..422327089e0f 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -360,8 +360,8 @@ static ssize_t queue_poll_delay_show(struct request_queue *q, char *page) { int val; - if (q->poll_nsec == -1) - val = -1; + if (q->poll_nsec == BLK_MQ_POLL_CLASSIC) + val = BLK_MQ_POLL_CLASSIC; else val = q->poll_nsec / 1000; @@ -380,10 +380,12 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page, if (err < 0) return err; - if (val == -1) - q->poll_nsec = -1; - else + if (val == BLK_MQ_POLL_CLASSIC) + q->poll_nsec = BLK_MQ_POLL_CLASSIC; + else if (val >= 0) q->poll_nsec = val * 1000; + else + return -EINVAL; return count; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 0de92b29f589..5c58a3b2bf00 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -50,6 +50,9 @@ struct blk_stat_callback; /* Must be consistent with blk_mq_poll_stats_bkt() */ #define BLK_MQ_POLL_STATS_BKTS 16 +/* Doing classic polling */ +#define BLK_MQ_POLL_CLASSIC -1 + /* * Maximum number of blkcg policies allowed to be registered concurrently. * Defined here to simplify include dependency.
For q->poll_nsec == -1, means doing classic poll, not hybrid poll. We introduce a new flag BLK_MQ_POLL_CLASSIC to replace -1, which may make code much easier to read. Additionally, since val is an int obtained with kstrtoint(), val can be a negative value other than -1, so return -EINVAL for that case. Thanks to Damien Le Moal for some good suggestion. Signed-off-by: Yufen Yu <yuyufen@huawei.com> --- block/blk-mq.c | 4 ++-- block/blk-sysfs.c | 12 +++++++----- include/linux/blkdev.h | 3 +++ 3 files changed, 12 insertions(+), 7 deletions(-)