Hi Alan, On Tue, Feb 05, 2013 at 04:03:15PM +0800, Aaron Lu wrote: > From: Lin Ming <ming.m.lin@xxxxxxxxx> > > When a request is added: > If device is suspended or is suspending and the request is not a > PM request, resume the device. > > When the last request finishes: > Call pm_runtime_mark_last_busy(). > > When pick a request: > If device is resuming/suspending, then only PM request is allowed > to go. I think I should add the following words in patch 2 & 3's changelog: The idea and API is designed by Alan Stern and described here: http://marc.info/?l=linux-scsi&m=133727953625963&w=2 to reflect your credit if you don't object. Please let me know what do you think, or if there is a better way to reflect this, please feel free to let me know. Thanks, Aaron > > Signed-off-by: Lin Ming <ming.m.lin@xxxxxxxxx> > Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> > --- > block/blk-core.c | 39 +++++++++++++++++++++++++++++++++++++++ > block/elevator.c | 26 ++++++++++++++++++++++++++ > 2 files changed, 65 insertions(+) > > diff --git a/block/blk-core.c b/block/blk-core.c > index ce7d366..81f173e 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -1264,6 +1264,16 @@ void part_round_stats(int cpu, struct hd_struct *part) > } > EXPORT_SYMBOL_GPL(part_round_stats); > > +#ifdef CONFIG_PM_RUNTIME > +static void blk_pm_put_request(struct request *rq) > +{ > + if (rq->q->dev && !(rq->cmd_flags & REQ_PM) && !--rq->q->nr_pending) > + pm_runtime_mark_last_busy(rq->q->dev); > +} > +#else > +static inline void blk_pm_put_request(struct request *rq) {} > +#endif > + > /* > * queue lock must be held > */ > @@ -1274,6 +1284,8 @@ void __blk_put_request(struct request_queue *q, struct request *req) > if (unlikely(--req->ref_count)) > return; > > + blk_pm_put_request(req); > + > elv_completed_request(q, req); > > /* this is a bio leak */ > @@ -2051,6 +2063,28 @@ static void blk_account_io_done(struct request *req) > } > } > > +#ifdef CONFIG_PM_RUNTIME > +/* > + * Don't process normal requests when queue is suspended > + * or in the process of suspending/resuming > + */ > +static struct request *blk_pm_peek_request(struct request_queue *q, > + struct request *rq) > +{ > + if (q->dev && (q->rpm_status == RPM_SUSPENDED || > + (q->rpm_status != RPM_ACTIVE && !(rq->cmd_flags & REQ_PM)))) > + return NULL; > + else > + return rq; > +} > +#else > +static inline struct request *blk_pm_peek_request(struct request_queue *q, > + struct request *rq) > +{ > + return rq; > +} > +#endif > + > /** > * blk_peek_request - peek at the top of a request queue > * @q: request queue to peek at > @@ -2073,6 +2107,11 @@ struct request *blk_peek_request(struct request_queue *q) > int ret; > > while ((rq = __elv_next_request(q)) != NULL) { > + > + rq = blk_pm_peek_request(q, rq); > + if (!rq) > + break; > + > if (!(rq->cmd_flags & REQ_STARTED)) { > /* > * This is the first time the device driver > diff --git a/block/elevator.c b/block/elevator.c > index 11683bb..29c5c7e 100644 > --- a/block/elevator.c > +++ b/block/elevator.c > @@ -34,6 +34,7 @@ > #include <linux/blktrace_api.h> > #include <linux/hash.h> > #include <linux/uaccess.h> > +#include <linux/pm_runtime.h> > > #include <trace/events/block.h> > > @@ -515,6 +516,27 @@ void elv_bio_merged(struct request_queue *q, struct request *rq, > e->type->ops.elevator_bio_merged_fn(q, rq, bio); > } > > +#ifdef CONFIG_PM_RUNTIME > +static void blk_pm_requeue_request(struct request *rq) > +{ > + if (rq->q->dev && !(rq->cmd_flags & REQ_PM)) > + rq->q->nr_pending--; > +} > + > +static void blk_pm_add_request(struct request_queue *q, struct request *rq) > +{ > + if (q->dev && !(rq->cmd_flags & REQ_PM) && q->nr_pending++ == 0 && > + (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING)) > + pm_request_resume(q->dev); > +} > +#else > +static inline void blk_pm_requeue_request(struct request *rq) {} > +static inline void blk_pm_add_request(struct request_queue *q, > + struct request *rq) > +{ > +} > +#endif > + > void elv_requeue_request(struct request_queue *q, struct request *rq) > { > /* > @@ -529,6 +551,8 @@ void elv_requeue_request(struct request_queue *q, struct request *rq) > > rq->cmd_flags &= ~REQ_STARTED; > > + blk_pm_requeue_request(rq); > + > __elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE); > } > > @@ -551,6 +575,8 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where) > { > trace_block_rq_insert(q, rq); > > + blk_pm_add_request(q, rq); > + > rq->q = q; > > if (rq->cmd_flags & REQ_SOFTBARRIER) { > -- > 1.8.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
