From 3719094ec2dec411b3151f10048316d787e086f9 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Wed, 10 Nov 2010 12:08:37 +0100 Subject: [PATCH] drbd: Starting with protocol 96 we can allow app-IO while receiving the bitmap * C_STARTING_SYNC_S, C_STARTING_SYNC_T In these states the bitmap gets written to disk. Locking out of app-IO is done by using the drbd_queue_bitmap_io() and drbd_bitmap_io() functions these days. It is no longer necessary to lock out app-IO based on the connection state. App-IO that may come in after the BITMAP_IO flag got cleared before the state transition to C_SYNC_(SOURCE|TARGET) does not get mirrored, sets a bit in the local bitmap, that is already set, therefore changes nothing. * C_WF_BITMAP_S In this state we send updates (P_OUT_OF_SYNC packets). With that we make sure they have the same number of bits when going into the C_SYNC_(SOURCE|TARGET) connection state. * C_UNCONNECTED: The receiver starts, no need to lock out IO. * C_DISCONNECTING: in drbd_disconnect() we had a wait_event() to wait until ap_bio_cnt reaches 0. Removed that. * C_TIMEOUT, C_BROKEN_PIPE, C_NETWORK_FAILURE C_PROTOCOL_ERROR, C_TEAR_DOWN: Same as C_DISCONNECTING * C_WF_REPORT_PARAMS: IO still possible since that is still like C_WF_CONNECTION. And we do not need to send barriers in C_WF_BITMAP_S connection state. Allow concurrent accesses to the bitmap when receiving the bitmap. Everything gets ORed anyways. A drbd_free_tl_hash() is in after_state_chg_work(). At that point all the work items of the last connections must have been processed. Introduced a call to drbd_free_tl_hash() into drbd_free_mdev() for paranoia reasons. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_int.h | 19 +++++++++------ drivers/block/drbd/drbd_main.c | 1 + drivers/block/drbd/drbd_receiver.c | 13 ++--------- drivers/block/drbd/drbd_req.c | 37 +++++++++++++++++++----------- 4 files changed, 39 insertions(+), 31 deletions(-) diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 9a944604939f..38bbaba8bd89 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -2213,8 +2213,9 @@ static inline int drbd_get_max_buffers(struct drbd_conf *mdev) return mxb; } -static inline int drbd_state_is_stable(union drbd_state s) +static inline int drbd_state_is_stable(struct drbd_conf *mdev) { + union drbd_state s = mdev->state; /* DO NOT add a default clause, we want the compiler to warn us * for any newly introduced state we may have forgotten to add here */ @@ -2233,11 +2234,7 @@ static inline int drbd_state_is_stable(union drbd_state s) case C_PAUSED_SYNC_T: case C_AHEAD: case C_BEHIND: - /* maybe stable, look at the disk state */ - break; - - /* no new io accepted during tansitional states - * like handshake or teardown */ + /* transitional states, IO allowed */ case C_DISCONNECTING: case C_UNCONNECTED: case C_TIMEOUT: @@ -2248,7 +2245,15 @@ static inline int drbd_state_is_stable(union drbd_state s) case C_WF_REPORT_PARAMS: case C_STARTING_SYNC_S: case C_STARTING_SYNC_T: + break; + + /* Allow IO in BM exchange states with new protocols */ case C_WF_BITMAP_S: + if (mdev->agreed_pro_version < 96) + return 0; + break; + + /* no new io accepted in these states */ case C_WF_BITMAP_T: case C_WF_SYNC_UUID: case C_MASK: @@ -2297,7 +2302,7 @@ static inline int __inc_ap_bio_cond(struct drbd_conf *mdev) * to start during "stable" states. */ /* no new io accepted when attaching or detaching the disk */ - if (!drbd_state_is_stable(mdev->state)) + if (!drbd_state_is_stable(mdev)) return 0; /* since some older kernels don't have atomic_add_unless, diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 74a6d55259af..14afbd4e53a5 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -3334,6 +3334,7 @@ void drbd_free_mdev(struct drbd_conf *mdev) put_disk(mdev->vdisk); blk_cleanup_queue(mdev->rq_queue); free_cpumask_var(mdev->cpu_mask); + drbd_free_tl_hash(mdev); kfree(mdev); } diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 0630a2e122d3..f4aba9f894ba 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -3468,9 +3468,7 @@ static int receive_bitmap(struct drbd_conf *mdev, enum drbd_packets cmd, unsigne int ok = FALSE; struct p_header80 *h = &mdev->data.rbuf.header.h80; - wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt)); - - drbd_bm_lock(mdev, "receive bitmap"); + /* drbd_bm_lock(mdev, "receive bitmap"); By intention no bm_lock */ /* maybe we should use some per thread scratch page, * and allocate that during initial device creation? */ @@ -3542,7 +3540,7 @@ static int receive_bitmap(struct drbd_conf *mdev, enum drbd_packets cmd, unsigne ok = TRUE; out: - drbd_bm_unlock(mdev); + /* drbd_bm_unlock(mdev); by intention no lock */ if (ok && mdev->state.conn == C_WF_BITMAP_S) drbd_start_resync(mdev, C_SYNC_SOURCE); free_page((unsigned long) buffer); @@ -3804,13 +3802,6 @@ static void drbd_disconnect(struct drbd_conf *mdev) if (os.conn == C_DISCONNECTING) { wait_event(mdev->net_cnt_wait, atomic_read(&mdev->net_cnt) == 0); - if (!is_susp(mdev->state)) { - /* we must not free the tl_hash - * while application io is still on the fly */ - wait_event(mdev->misc_wait, !atomic_read(&mdev->ap_bio_cnt)); - drbd_free_tl_hash(mdev); - } - crypto_free_hash(mdev->cram_hmac_tfm); mdev->cram_hmac_tfm = NULL; diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index eff0fbf69dd4..4cb8247d83c9 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -142,7 +142,7 @@ static void _about_to_complete_local_write(struct drbd_conf *mdev, /* before we can signal completion to the upper layers, * we may need to close the current epoch */ - if (mdev->state.conn >= C_CONNECTED && mdev->state.conn < C_AHEAD && + if (mdev->state.conn >= C_WF_BITMAP_T && mdev->state.conn < C_AHEAD && req->epoch == mdev->newest_tle->br_number) queue_barrier(mdev); @@ -757,6 +757,23 @@ static int drbd_may_do_local_read(struct drbd_conf *mdev, sector_t sector, int s return 0 == drbd_bm_count_bits(mdev, sbnr, ebnr); } +static int drbd_should_do_remote(struct drbd_conf *mdev) +{ + union drbd_state s = mdev->state; + + return s.pdsk == D_UP_TO_DATE || + (s.pdsk >= D_INCONSISTENT && + s.conn >= C_WF_BITMAP_T && + s.conn < C_AHEAD); +} +static int drbd_should_send_oos(struct drbd_conf *mdev) +{ + union drbd_state s = mdev->state; + + return s.pdsk >= D_INCONSISTENT && + (s.conn == C_AHEAD || s.conn == C_WF_BITMAP_S); +} + static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time) { const int rw = bio_rw(bio); @@ -828,12 +845,9 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, uns drbd_al_begin_io(mdev, sector); } - remote = remote && (mdev->state.pdsk == D_UP_TO_DATE || - (mdev->state.pdsk >= D_INCONSISTENT && - mdev->state.conn >= C_CONNECTED && - mdev->state.conn < C_AHEAD)); - send_oos = (rw == WRITE && mdev->state.conn == C_AHEAD && - mdev->state.pdsk >= D_INCONSISTENT); + remote = remote && drbd_should_do_remote(mdev); + send_oos = rw == WRITE && drbd_should_send_oos(mdev); + D_ASSERT(!(remote && send_oos)); if (!(local || remote) && !is_susp(mdev->state)) { if (__ratelimit(&drbd_ratelimit_state)) @@ -873,12 +887,9 @@ allocate_barrier: } if (remote || send_oos) { - remote = (mdev->state.pdsk == D_UP_TO_DATE || - (mdev->state.pdsk >= D_INCONSISTENT && - mdev->state.conn >= C_CONNECTED && - mdev->state.conn < C_AHEAD)); - send_oos = (rw == WRITE && mdev->state.conn == C_AHEAD && - mdev->state.pdsk >= D_INCONSISTENT); + remote = drbd_should_do_remote(mdev); + send_oos = rw == WRITE && drbd_should_send_oos(mdev); + D_ASSERT(!(remote && send_oos)); if (!(remote || send_oos)) dev_warn(DEV, "lost connection while grabbing the req_lock!\n"); -- 2.34.1