From 6d9febe237146156947f0da8407c620b5c33c1df Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Tue, 19 Mar 2013 18:16:50 +0100 Subject: drbd: split __drbd_make_request in before and after drbd_al_begin_io This is in preparation to be able to defer requests that need to wait for an activity log transaction to a submitter workqueue. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_req.c | 40 ++++++++++++++++++++++++++++++---------- 1 file changed, 30 insertions(+), 10 deletions(-) (limited to 'drivers/block/drbd/drbd_req.c') diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 7d1ff1aaeb71..96d5968fc1e4 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -34,14 +34,14 @@ static bool drbd_may_do_local_read(struct drbd_conf *mdev, sector_t sector, int size); /* Update disk stats at start of I/O request */ -static void _drbd_start_io_acct(struct drbd_conf *mdev, struct drbd_request *req, struct bio *bio) +static void _drbd_start_io_acct(struct drbd_conf *mdev, struct drbd_request *req) { - const int rw = bio_data_dir(bio); + const int rw = bio_data_dir(req->master_bio); int cpu; cpu = part_stat_lock(); part_round_stats(cpu, &mdev->vdisk->part0); part_stat_inc(cpu, &mdev->vdisk->part0, ios[rw]); - part_stat_add(cpu, &mdev->vdisk->part0, sectors[rw], bio_sectors(bio)); + part_stat_add(cpu, &mdev->vdisk->part0, sectors[rw], req->i.size >> 9); (void) cpu; /* The macro invocations above want the cpu argument, I do not like the compiler warning about cpu only assigned but never used... */ part_inc_in_flight(&mdev->vdisk->part0, rw); @@ -1020,12 +1020,16 @@ drbd_submit_req_private_bio(struct drbd_request *req) bio_endio(bio, -EIO); } -void __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time) +/* returns the new drbd_request pointer, if the caller is expected to + * drbd_send_and_submit() it (to save latency), or NULL if we queued the + * request on the submitter thread. + * Returns ERR_PTR(-ENOMEM) if we cannot allocate a drbd_request. + */ +struct drbd_request * +drbd_request_prepare(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time) { - const int rw = bio_rw(bio); - struct bio_and_error m = { NULL, }; + const int rw = bio_data_dir(bio); struct drbd_request *req; - bool no_remote = false; /* allocate outside of all locks; */ req = drbd_req_new(mdev, bio); @@ -1035,7 +1039,7 @@ void __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long * if user cannot handle io errors, that's not our business. */ dev_err(DEV, "could not kmalloc() req\n"); bio_endio(bio, -ENOMEM); - return; + return ERR_PTR(-ENOMEM); } req->start_time = start_time; @@ -1057,6 +1061,15 @@ void __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long drbd_al_begin_io(mdev, &req->i, true); } + return req; +} + +static void drbd_send_and_submit(struct drbd_conf *mdev, struct drbd_request *req) +{ + const int rw = bio_rw(req->master_bio); + struct bio_and_error m = { NULL, }; + bool no_remote = false; + spin_lock_irq(&mdev->tconn->req_lock); if (rw == WRITE) { /* This may temporarily give up the req_lock, @@ -1079,7 +1092,7 @@ void __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long } /* Update disk stats */ - _drbd_start_io_acct(mdev, req, bio); + _drbd_start_io_acct(mdev, req); /* We fail READ/READA early, if we can not serve it. * We must do this before req is registered on any lists. @@ -1137,7 +1150,14 @@ out: if (m.bio) complete_master_bio(mdev, &m); - return; +} + +void __drbd_make_request(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time) +{ + struct drbd_request *req = drbd_request_prepare(mdev, bio, start_time); + if (IS_ERR_OR_NULL(req)) + return; + drbd_send_and_submit(mdev, req); } void drbd_make_request(struct request_queue *q, struct bio *bio) -- cgit v1.2.3