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| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2010-12-15 08:59:11 +0100 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2011-03-10 11:43:19 +0100 |
| commit | 19f843aa08e2d8f87a09b4c2edc43b00638423a8 (patch) | |
| tree | 49919bd17ba7e03eb7cb76175910714d55704997 /drivers/block/drbd/drbd_main.c | |
| parent | 95a0f10cddbf93ce89c175ac1c53dad2d20ad309 (diff) | |
| download | lwn-19f843aa08e2d8f87a09b4c2edc43b00638423a8.tar.gz lwn-19f843aa08e2d8f87a09b4c2edc43b00638423a8.zip | |
drbd: bitmap keep track of changes vs on-disk bitmap
When we set or clear bits in a bitmap page,
also set a flag in the page->private pointer.
This allows us to skip writes of unchanged pages.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_main.c')
| -rw-r--r-- | drivers/block/drbd/drbd_main.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 67fffad213ec..57ed7181742d 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -1289,6 +1289,26 @@ static void abw_start_sync(struct drbd_conf *mdev, int rv) } } +int drbd_bitmap_io_from_worker(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why) +{ + int rv; + + D_ASSERT(current == mdev->worker.task); + + /* open coded non-blocking drbd_suspend_io(mdev); */ + set_bit(SUSPEND_IO, &mdev->flags); + if (!is_susp(mdev->state)) + D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0); + + drbd_bm_lock(mdev, why); + rv = io_fn(mdev); + drbd_bm_unlock(mdev); + + drbd_resume_io(mdev); + + return rv; +} + /** * after_state_ch() - Perform after state change actions that may sleep * @mdev: DRBD device. @@ -1404,7 +1424,12 @@ static void after_state_ch(struct drbd_conf *mdev, union drbd_state os, /* D_DISKLESS Peer becomes secondary */ if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY) - drbd_al_to_on_disk_bm(mdev); + drbd_bitmap_io_from_worker(mdev, &drbd_bm_write, "demote diskless peer"); + put_ldev(mdev); + } + + if (os.role == R_PRIMARY && ns.role == R_SECONDARY && get_ldev(mdev)) { + drbd_bitmap_io_from_worker(mdev, &drbd_bm_write, "demote"); put_ldev(mdev); } |