diff options
| -rw-r--r-- | drivers/block/drbd/drbd_actlog.c | 104 | ||||
| -rw-r--r-- | drivers/block/drbd/drbd_int.h | 1 |
2 files changed, 72 insertions, 33 deletions
diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c index 1d7244d2a910..e4f1231c2ef2 100644 --- a/drivers/block/drbd/drbd_actlog.c +++ b/drivers/block/drbd/drbd_actlog.c @@ -104,7 +104,6 @@ struct update_al_work { int err; }; -static int al_write_transaction(struct drbd_conf *mdev, bool delegate); void *drbd_md_get_buffer(struct drbd_conf *mdev) { @@ -246,30 +245,37 @@ static struct lc_element *_al_get(struct drbd_conf *mdev, unsigned int enr) return al_ext; } -/* - * @delegate: delegate activity log I/O to the worker thread - */ -void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool delegate) +bool drbd_al_begin_io_fastpath(struct drbd_conf *mdev, struct drbd_interval *i) { /* for bios crossing activity log extent boundaries, * 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); - unsigned enr; - bool need_transaction = false; - bool locked = false; + bool fastpath_ok = true; - /* When called through generic_make_request(), we must delegate - * activity log I/O to the worker thread: a further request - * submitted via generic_make_request() within the same task - * would be queued on current->bio_list, and would only start - * after this function returns (see generic_make_request()). - * - * However, if we *are* the worker, we must not delegate to ourselves. - */ + D_ASSERT((unsigned)(last - first) <= 1); + D_ASSERT(atomic_read(&mdev->local_cnt) > 0); + + /* FIXME figure out a fast path for bios crossing AL extent boundaries */ + 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; +} - if (delegate) - BUG_ON(current == mdev->tconn->worker.task); +bool drbd_al_begin_io_prepare(struct drbd_conf *mdev, struct drbd_interval *i) +{ + /* for bios crossing activity log extent boundaries, + * 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); + unsigned enr; + bool need_transaction = false; D_ASSERT(first <= last); D_ASSERT(atomic_read(&mdev->local_cnt) > 0); @@ -280,11 +286,28 @@ void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool dele if (al_ext->lc_number != enr) need_transaction = true; } + return need_transaction; +} - /* If *this* request was to an already active extent, - * we're done, even if there are pending changes. */ - if (!need_transaction) - return; +static int al_write_transaction(struct drbd_conf *mdev, bool delegate); + +/* When called through generic_make_request(), we must delegate + * activity log I/O to the worker thread: a further request + * submitted via generic_make_request() within the same task + * would be queued on current->bio_list, and would only start + * after this function returns (see generic_make_request()). + * + * However, if we *are* the worker, we must not delegate to ourselves. + */ + +/* + * @delegate: delegate activity log I/O to the worker thread + */ +void drbd_al_begin_io_commit(struct drbd_conf *mdev, bool delegate) +{ + bool locked = false; + + BUG_ON(delegate && current == mdev->tconn->worker.task); /* Serialize multiple transactions. * This uses test_and_set_bit, memory barrier is implicit. @@ -303,11 +326,8 @@ void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool dele write_al_updates = rcu_dereference(mdev->ldev->disk_conf)->al_updates; rcu_read_unlock(); - if (write_al_updates) { + if (write_al_updates) al_write_transaction(mdev, delegate); - mdev->al_writ_cnt++; - } - spin_lock_irq(&mdev->al_lock); /* FIXME if (err) @@ -321,6 +341,17 @@ void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool dele } } +/* + * @delegate: delegate activity log I/O to the worker thread + */ +void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool delegate) +{ + BUG_ON(delegate && current == mdev->tconn->worker.task); + + if (drbd_al_begin_io_prepare(mdev, i)) + drbd_al_begin_io_commit(mdev, delegate); +} + void drbd_al_complete_io(struct drbd_conf *mdev, struct drbd_interval *i) { /* for bios crossing activity log extent boundaries, @@ -478,15 +509,22 @@ _al_write_transaction(struct drbd_conf *mdev) crc = crc32c(0, buffer, 4096); buffer->crc32c = cpu_to_be32(crc); - /* normal execution path goes through all three branches */ if (drbd_bm_write_hinted(mdev)) err = -EIO; - /* drbd_chk_io_error done already */ - else if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) { - err = -EIO; - drbd_chk_io_error(mdev, 1, DRBD_META_IO_ERROR); - } else { - mdev->al_tr_number++; + else { + bool write_al_updates; + rcu_read_lock(); + write_al_updates = rcu_dereference(mdev->ldev->disk_conf)->al_updates; + rcu_read_unlock(); + if (write_al_updates) { + if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) { + err = -EIO; + drbd_chk_io_error(mdev, 1, DRBD_META_IO_ERROR); + } else { + mdev->al_tr_number++; + mdev->al_writ_cnt++; + } + } } drbd_md_put_buffer(mdev); diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index a6b71b6076b5..b7b52dd42325 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -1611,6 +1611,7 @@ extern const char *drbd_conn_str(enum drbd_conns s); extern const char *drbd_role_str(enum drbd_role s); /* drbd_actlog.c */ +extern bool drbd_al_begin_io_fastpath(struct drbd_conf *mdev, struct drbd_interval *i); extern void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool delegate); extern void drbd_al_complete_io(struct drbd_conf *mdev, struct drbd_interval *i); extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector); |