From 6c3c4355d6bfa418db828684e67910c559402264 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Tue, 19 Mar 2013 18:16:53 +0100 Subject: drbd: split out some helper functions to drbd_al_begin_io To make the code easier to follow, use an explicit find_active_resync_extent(), and add a "nonblock" parameter to _al_get(). Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_actlog.c | 49 +++++++++++++++++++++++----------------- 1 file changed, 28 insertions(+), 21 deletions(-) (limited to 'drivers/block/drbd') diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c index e4f1231c2ef2..ff03f9053316 100644 --- a/drivers/block/drbd/drbd_actlog.c +++ b/drivers/block/drbd/drbd_actlog.c @@ -222,25 +222,37 @@ int drbd_md_sync_page_io(struct drbd_conf *mdev, struct drbd_backing_dev *bdev, return err; } -static struct lc_element *_al_get(struct drbd_conf *mdev, unsigned int enr) +static struct bm_extent *find_active_resync_extent(struct drbd_conf *mdev, unsigned int enr) { - struct lc_element *al_ext; struct lc_element *tmp; - int wake; - - spin_lock_irq(&mdev->al_lock); tmp = lc_find(mdev->resync, enr/AL_EXT_PER_BM_SECT); if (unlikely(tmp != NULL)) { struct bm_extent *bm_ext = lc_entry(tmp, struct bm_extent, lce); - if (test_bit(BME_NO_WRITES, &bm_ext->flags)) { - wake = !test_and_set_bit(BME_PRIORITY, &bm_ext->flags); - spin_unlock_irq(&mdev->al_lock); - if (wake) - wake_up(&mdev->al_wait); - return NULL; - } + if (test_bit(BME_NO_WRITES, &bm_ext->flags)) + return bm_ext; } - al_ext = lc_get(mdev->act_log, enr); + return NULL; +} + +static struct lc_element *_al_get(struct drbd_conf *mdev, unsigned int enr, bool nonblock) +{ + struct lc_element *al_ext; + struct bm_extent *bm_ext; + int wake; + + spin_lock_irq(&mdev->al_lock); + bm_ext = find_active_resync_extent(mdev, enr); + if (bm_ext) { + wake = !test_and_set_bit(BME_PRIORITY, &bm_ext->flags); + spin_unlock_irq(&mdev->al_lock); + if (wake) + wake_up(&mdev->al_wait); + return NULL; + } + if (nonblock) + al_ext = lc_try_get(mdev->act_log, enr); + else + al_ext = lc_get(mdev->act_log, enr); spin_unlock_irq(&mdev->al_lock); return al_ext; } @@ -251,7 +263,6 @@ bool drbd_al_begin_io_fastpath(struct drbd_conf *mdev, struct drbd_interval *i) * we may need to activate two extents in one go */ unsigned first = i->sector >> (AL_EXTENT_SHIFT-9); unsigned last = i->size == 0 ? first : (i->sector + (i->size >> 9) - 1) >> (AL_EXTENT_SHIFT-9); - bool fastpath_ok = true; D_ASSERT((unsigned)(last - first) <= 1); D_ASSERT(atomic_read(&mdev->local_cnt) > 0); @@ -260,12 +271,7 @@ bool drbd_al_begin_io_fastpath(struct drbd_conf *mdev, struct drbd_interval *i) if (first != last) return false; - spin_lock_irq(&mdev->al_lock); - fastpath_ok = - lc_find(mdev->resync, first/AL_EXT_PER_BM_SECT) == NULL && - lc_try_get(mdev->act_log, first) != NULL; - spin_unlock_irq(&mdev->al_lock); - return fastpath_ok; + return _al_get(mdev, first, true); } bool drbd_al_begin_io_prepare(struct drbd_conf *mdev, struct drbd_interval *i) @@ -282,7 +288,8 @@ bool drbd_al_begin_io_prepare(struct drbd_conf *mdev, struct drbd_interval *i) for (enr = first; enr <= last; enr++) { struct lc_element *al_ext; - wait_event(mdev->al_wait, (al_ext = _al_get(mdev, enr)) != NULL); + wait_event(mdev->al_wait, + (al_ext = _al_get(mdev, enr, false)) != NULL); if (al_ext->lc_number != enr) need_transaction = true; } -- cgit v1.2.3