From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: [PATCH 3/5] dm-multipath: remove process_queued_ios() Date: Fri, 31 Jan 2014 10:10:42 +0100 Message-ID: <1391159444-17987-4-git-send-email-hare@suse.de> References: <1391159444-17987-1-git-send-email-hare@suse.de> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1391159444-17987-1-git-send-email-hare@suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Alasdair Kergon Cc: Jun'ichi Nomura , dm-devel@redhat.com, Mike Snitzer List-Id: dm-devel.ids Doesn't serve any real purpose anymore; dm_table_run_queue() will already move things to a workqueue, so we don't need to do it ourselves. Signed-off-by: Hannes Reinecke --- drivers/md/dm-mpath.c | 67 ++++++++++++++++++++------------------------------- 1 file changed, 26 insertions(+), 41 deletions(-) diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 39fd166..7122ac3 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -93,8 +93,6 @@ struct multipath { unsigned pg_init_count; /* Number of times pg_init called */ unsigned pg_init_delay_msecs; /* Number of msecs before pg_init retry */ - struct work_struct process_queued_ios; - struct work_struct trigger_event; /* @@ -119,7 +117,6 @@ typedef int (*action_fn) (struct pgpath *pgpath); static struct kmem_cache *_mpio_cache; static struct workqueue_struct *kmultipathd, *kmpath_handlerd; -static void process_queued_ios(struct work_struct *work); static void trigger_event(struct work_struct *work); static void activate_path(struct work_struct *work); static int __pgpath_busy(struct pgpath *pgpath); @@ -197,7 +194,6 @@ static struct multipath *alloc_multipath(struct dm_target *ti) spin_lock_init(&m->lock); m->queue_io = 1; m->pg_init_delay_msecs = DM_PG_INIT_DELAY_DEFAULT; - INIT_WORK(&m->process_queued_ios, process_queued_ios); INIT_WORK(&m->trigger_event, trigger_event); init_waitqueue_head(&m->pg_init_wait); mutex_init(&m->work_mutex); @@ -438,41 +434,13 @@ static int queue_if_no_path(struct multipath *m, unsigned queue_if_no_path, m->saved_queue_if_no_path = queue_if_no_path; m->queue_if_no_path = queue_if_no_path; if (!m->queue_if_no_path) - queue_work(kmultipathd, &m->process_queued_ios); + dm_table_run_queue(m->ti->table); spin_unlock_irqrestore(&m->lock, flags); return 0; } -static void process_queued_ios(struct work_struct *work) -{ - struct multipath *m = - container_of(work, struct multipath, process_queued_ios); - struct pgpath *pgpath = NULL; - unsigned must_queue = 1; - unsigned long flags; - - spin_lock_irqsave(&m->lock, flags); - - if (!m->current_pgpath) - __choose_pgpath(m, 0); - - pgpath = m->current_pgpath; - - if ((pgpath && !m->queue_io) || - (!pgpath && !m->queue_if_no_path)) - must_queue = 0; - - if (m->pg_init_required && !m->pg_init_in_progress && pgpath && - !m->pg_init_disabled) - __pg_init_all_paths(m); - - spin_unlock_irqrestore(&m->lock, flags); - if (!must_queue) - dm_table_run_queue(m->ti->table); -} - /* * An event is triggered whenever a path is taken out of use. * Includes path failure and PG bypass. @@ -1019,7 +987,7 @@ static int reinstate_path(struct pgpath *pgpath) if (!m->nr_valid_paths++) { m->current_pgpath = NULL; - queue_work(kmultipathd, &m->process_queued_ios); + dm_table_run_queue(m->ti->table); } else if (m->hw_handler_name && (m->current_pg == pgpath->pg)) { if (queue_work(kmpath_handlerd, &pgpath->activate_path.work)) m->pg_init_in_progress++; @@ -1158,7 +1126,7 @@ static void pg_init_done(void *data, int errors) struct priority_group *pg = pgpath->pg; struct multipath *m = pg->m; unsigned long flags; - unsigned delay_retry = 0; + unsigned long pg_init_delay = 0; /* device or driver problems */ switch (errors) { @@ -1185,7 +1153,7 @@ static void pg_init_done(void *data, int errors) break; case SCSI_DH_RETRY: /* Wait before retrying. */ - delay_retry = 1; + pg_init_delay = msecs_to_jiffies(m->pg_init_delay_msecs); case SCSI_DH_IMM_RETRY: case SCSI_DH_RES_TEMP_UNAVAIL: if (pg_init_limit_reached(m, pgpath)) @@ -1217,9 +1185,21 @@ static void pg_init_done(void *data, int errors) if (!m->pg_init_required) m->queue_io = 0; - - m->pg_init_delay_retry = delay_retry; - queue_work(kmultipathd, &m->process_queued_ios); + else { + if (!pg_init_delay) { + m->pg_init_delay_retry = 0; + /* + * Add a small delay to move the + * activation to a workqueue + */ + pg_init_delay = HZ / 50; + } else + m->pg_init_delay_retry = 1; + if (queue_delayed_work(kmpath_handlerd, &pgpath->activate_path, + pg_init_delay)) + m->pg_init_in_progress++; + goto out; + } /* * Wake up any thread waiting to suspend. @@ -1593,8 +1573,13 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd, if (!r && ti->len != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT) r = scsi_verify_blk_ioctl(NULL, cmd); - if (r == -ENOTCONN && !fatal_signal_pending(current)) - queue_work(kmultipathd, &m->process_queued_ios); + if (r == -ENOTCONN && !fatal_signal_pending(current)) { + spin_lock_irqsave(&m->lock, flags); + if (m->current_pgpath && m->pg_init_required) + __pg_init_all_paths(m); + spin_unlock_irqrestore(&m->lock, flags); + dm_table_run_queue(m->ti->table); + } return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg); } -- 1.7.12.4