From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: [md PATCH 3/5] md: move suspend_hi/lo handling into core md code Date: Tue, 17 Oct 2017 13:46:43 +1100 Message-ID: <150820840349.1646.9916811766142195995.stgit@noble> References: <150820826980.1646.6380214598725492144.stgit@noble> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <150820826980.1646.6380214598725492144.stgit@noble> Sender: linux-raid-owner@vger.kernel.org To: Shaohua Li Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids responding to ->suspend_lo and ->suspend_hi is similar to responding to ->suspended. It is best to wait in the common core code without incrementing ->active_io. This allows mddev_suspend()/mddev_resume() to work while requests are waiting for suspend_lo/hi to change. This is will be important after a subsequent patch which uses mddev_suspend() to synchronize updating for suspend_lo/hi. So move the code for testing suspend_lo/hi out of raid1.c and raid5.c, and place it in md.c Signed-off-by: NeilBrown --- drivers/md/md.c | 29 +++++++++++++++++++++++------ drivers/md/raid1.c | 12 ++++-------- drivers/md/raid5.c | 22 ---------------------- 3 files changed, 27 insertions(+), 36 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 308456842d3e..f8d0e41120cb 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -266,16 +266,31 @@ static DEFINE_SPINLOCK(all_mddevs_lock); * call has finished, the bio has been linked into some internal structure * and so is visible to ->quiesce(), so we don't need the refcount any more. */ +static bool is_suspended(struct mddev *mddev, struct bio *bio) +{ + if (mddev->suspended) + return true; + if (bio_data_dir(bio) != WRITE) + return false; + if (mddev->suspend_lo >= mddev->suspend_hi) + return false; + if (bio->bi_iter.bi_sector >= mddev->suspend_hi) + return false; + if (bio_end_sector(bio) < mddev->suspend_lo) + return false; + return true; +} + void md_handle_request(struct mddev *mddev, struct bio *bio) { check_suspended: rcu_read_lock(); - if (mddev->suspended) { + if (is_suspended(mddev, bio)) { DEFINE_WAIT(__wait); for (;;) { prepare_to_wait(&mddev->sb_wait, &__wait, TASK_UNINTERRUPTIBLE); - if (!mddev->suspended) + if (!is_suspended(mddev, bio)) break; rcu_read_unlock(); schedule(); @@ -4843,10 +4858,11 @@ suspend_lo_store(struct mddev *mddev, const char *buf, size_t len) goto unlock; old = mddev->suspend_lo; mddev->suspend_lo = new; - if (new >= old) + if (new >= old) { /* Shrinking suspended region */ + wake_up(&mddev->sb_wait); mddev->pers->quiesce(mddev, 2); - else { + } else { /* Expanding suspended region - need to wait */ mddev->pers->quiesce(mddev, 1); mddev->pers->quiesce(mddev, 0); @@ -4886,10 +4902,11 @@ suspend_hi_store(struct mddev *mddev, const char *buf, size_t len) goto unlock; old = mddev->suspend_hi; mddev->suspend_hi = new; - if (new <= old) + if (new <= old) { /* Shrinking suspended region */ + wake_up(&mddev->sb_wait); mddev->pers->quiesce(mddev, 2); - else { + } else { /* Expanding suspended region - need to wait */ mddev->pers->quiesce(mddev, 1); mddev->pers->quiesce(mddev, 0); diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index f3f3e40dc9d8..277a145b3ff5 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1310,11 +1310,9 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, */ - if ((bio_end_sector(bio) > mddev->suspend_lo && - bio->bi_iter.bi_sector < mddev->suspend_hi) || - (mddev_is_clustered(mddev) && + if (mddev_is_clustered(mddev) && md_cluster_ops->area_resyncing(mddev, WRITE, - bio->bi_iter.bi_sector, bio_end_sector(bio)))) { + bio->bi_iter.bi_sector, bio_end_sector(bio))) { /* * As the suspend_* range is controlled by userspace, we want @@ -1325,12 +1323,10 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, sigset_t full, old; prepare_to_wait(&conf->wait_barrier, &w, TASK_INTERRUPTIBLE); - if (bio_end_sector(bio) <= mddev->suspend_lo || - bio->bi_iter.bi_sector >= mddev->suspend_hi || - (mddev_is_clustered(mddev) && + if (mddev_is_clustered(mddev) && !md_cluster_ops->area_resyncing(mddev, WRITE, bio->bi_iter.bi_sector, - bio_end_sector(bio)))) + bio_end_sector(bio))) break; sigfillset(&full); sigprocmask(SIG_BLOCK, &full, &old); diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 928e24a07133..4f40ccd21cbb 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5682,28 +5682,6 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi) goto retry; } - if (rw == WRITE && - logical_sector >= mddev->suspend_lo && - logical_sector < mddev->suspend_hi) { - raid5_release_stripe(sh); - /* As the suspend_* range is controlled by - * userspace, we want an interruptible - * wait. - */ - prepare_to_wait(&conf->wait_for_overlap, - &w, TASK_INTERRUPTIBLE); - if (logical_sector >= mddev->suspend_lo && - logical_sector < mddev->suspend_hi) { - sigset_t full, old; - sigfillset(&full); - sigprocmask(SIG_BLOCK, &full, &old); - schedule(); - sigprocmask(SIG_SETMASK, &old, NULL); - do_prepare = true; - } - goto retry; - } - if (test_bit(STRIPE_EXPANDING, &sh->state) || !add_stripe_bio(sh, bi, dd_idx, rw, previous)) { /* Stripe is busy expanding or