drbd: Removed the BIO_RW_BARRIER support form the receiver/epoch code
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 1146faa..2952c12 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -49,11 +49,6 @@
#include "drbd_vli.h"
-struct flush_work {
- struct drbd_work w;
- struct drbd_epoch *epoch;
-};
-
enum finish_epoch {
FE_STILL_LIVE,
FE_DESTROYED,
@@ -66,16 +61,6 @@
static enum finish_epoch drbd_may_finish_epoch(struct drbd_conf *, struct drbd_epoch *, enum epoch_event);
static int e_end_block(struct drbd_conf *, struct drbd_work *, int);
-static struct drbd_epoch *previous_epoch(struct drbd_conf *mdev, struct drbd_epoch *epoch)
-{
- struct drbd_epoch *prev;
- spin_lock(&mdev->epoch_lock);
- prev = list_entry(epoch->list.prev, struct drbd_epoch, list);
- if (prev == epoch || prev == mdev->current_epoch)
- prev = NULL;
- spin_unlock(&mdev->epoch_lock);
- return prev;
-}
#define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN)
@@ -981,7 +966,7 @@
return TRUE;
}
-static enum finish_epoch drbd_flush_after_epoch(struct drbd_conf *mdev, struct drbd_epoch *epoch)
+static void drbd_flush(struct drbd_conf *mdev)
{
int rv;
@@ -997,24 +982,6 @@
}
put_ldev(mdev);
}
-
- return drbd_may_finish_epoch(mdev, epoch, EV_BARRIER_DONE);
-}
-
-static int w_flush(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
-{
- struct flush_work *fw = (struct flush_work *)w;
- struct drbd_epoch *epoch = fw->epoch;
-
- kfree(w);
-
- if (!test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags))
- drbd_flush_after_epoch(mdev, epoch);
-
- drbd_may_finish_epoch(mdev, epoch, EV_PUT |
- (mdev->state.conn < C_CONNECTED ? EV_CLEANUP : 0));
-
- return 1;
}
/**
@@ -1027,15 +994,13 @@
struct drbd_epoch *epoch,
enum epoch_event ev)
{
- int finish, epoch_size;
+ int epoch_size;
struct drbd_epoch *next_epoch;
- int schedule_flush = 0;
enum finish_epoch rv = FE_STILL_LIVE;
spin_lock(&mdev->epoch_lock);
do {
next_epoch = NULL;
- finish = 0;
epoch_size = atomic_read(&epoch->epoch_size);
@@ -1045,16 +1010,6 @@
break;
case EV_GOT_BARRIER_NR:
set_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags);
-
- /* Special case: If we just switched from WO_bio_barrier to
- WO_bdev_flush we should not finish the current epoch */
- if (test_bit(DE_CONTAINS_A_BARRIER, &epoch->flags) && epoch_size == 1 &&
- mdev->write_ordering != WO_bio_barrier &&
- epoch == mdev->current_epoch)
- clear_bit(DE_CONTAINS_A_BARRIER, &epoch->flags);
- break;
- case EV_BARRIER_DONE:
- set_bit(DE_BARRIER_IN_NEXT_EPOCH_DONE, &epoch->flags);
break;
case EV_BECAME_LAST:
/* nothing to do*/
@@ -1063,23 +1018,7 @@
if (epoch_size != 0 &&
atomic_read(&epoch->active) == 0 &&
- test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags) &&
- epoch->list.prev == &mdev->current_epoch->list &&
- !test_bit(DE_IS_FINISHING, &epoch->flags)) {
- /* Nearly all conditions are met to finish that epoch... */
- if (test_bit(DE_BARRIER_IN_NEXT_EPOCH_DONE, &epoch->flags) ||
- mdev->write_ordering == WO_none ||
- (epoch_size == 1 && test_bit(DE_CONTAINS_A_BARRIER, &epoch->flags)) ||
- ev & EV_CLEANUP) {
- finish = 1;
- set_bit(DE_IS_FINISHING, &epoch->flags);
- } else if (!test_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags) &&
- mdev->write_ordering == WO_bio_barrier) {
- atomic_inc(&epoch->active);
- schedule_flush = 1;
- }
- }
- if (finish) {
+ test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags)) {
if (!(ev & EV_CLEANUP)) {
spin_unlock(&mdev->epoch_lock);
drbd_send_b_ack(mdev, epoch->barrier_nr, epoch_size);
@@ -1102,6 +1041,7 @@
/* atomic_set(&epoch->active, 0); is already zero */
if (rv == FE_STILL_LIVE)
rv = FE_RECYCLED;
+ wake_up(&mdev->ee_wait);
}
}
@@ -1113,22 +1053,6 @@
spin_unlock(&mdev->epoch_lock);
- if (schedule_flush) {
- struct flush_work *fw;
- fw = kmalloc(sizeof(*fw), GFP_ATOMIC);
- if (fw) {
- fw->w.cb = w_flush;
- fw->epoch = epoch;
- drbd_queue_work(&mdev->data.work, &fw->w);
- } else {
- dev_warn(DEV, "Could not kmalloc a flush_work obj\n");
- set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags);
- /* That is not a recursion, only one level */
- drbd_may_finish_epoch(mdev, epoch, EV_BARRIER_DONE);
- drbd_may_finish_epoch(mdev, epoch, EV_PUT);
- }
- }
-
return rv;
}
@@ -1144,19 +1068,16 @@
[WO_none] = "none",
[WO_drain_io] = "drain",
[WO_bdev_flush] = "flush",
- [WO_bio_barrier] = "barrier",
};
pwo = mdev->write_ordering;
wo = min(pwo, wo);
- if (wo == WO_bio_barrier && mdev->ldev->dc.no_disk_barrier)
- wo = WO_bdev_flush;
if (wo == WO_bdev_flush && mdev->ldev->dc.no_disk_flush)
wo = WO_drain_io;
if (wo == WO_drain_io && mdev->ldev->dc.no_disk_drain)
wo = WO_none;
mdev->write_ordering = wo;
- if (pwo != mdev->write_ordering || wo == WO_bio_barrier)
+ if (pwo != mdev->write_ordering || wo == WO_bdev_flush)
dev_info(DEV, "Method to ensure write ordering: %s\n", write_ordering_str[mdev->write_ordering]);
}
@@ -1192,7 +1113,7 @@
bio->bi_sector = sector;
bio->bi_bdev = mdev->ldev->backing_bdev;
/* we special case some flags in the multi-bio case, see below
- * (REQ_UNPLUG, REQ_HARDBARRIER) */
+ * (REQ_UNPLUG) */
bio->bi_rw = rw;
bio->bi_private = e;
bio->bi_end_io = drbd_endio_sec;
@@ -1226,11 +1147,6 @@
bio->bi_rw &= ~REQ_UNPLUG;
drbd_generic_make_request(mdev, fault_type, bio);
-
- /* strip off REQ_HARDBARRIER,
- * unless it is the first or last bio */
- if (bios && bios->bi_next)
- bios->bi_rw &= ~REQ_HARDBARRIER;
} while (bios);
maybe_kick_lo(mdev);
return 0;
@@ -1244,45 +1160,9 @@
return -ENOMEM;
}
-/**
- * w_e_reissue() - Worker callback; Resubmit a bio, without REQ_HARDBARRIER set
- * @mdev: DRBD device.
- * @w: work object.
- * @cancel: The connection will be closed anyways (unused in this callback)
- */
-int w_e_reissue(struct drbd_conf *mdev, struct drbd_work *w, int cancel) __releases(local)
-{
- struct drbd_epoch_entry *e = (struct drbd_epoch_entry *)w;
- /* We leave DE_CONTAINS_A_BARRIER and EE_IS_BARRIER in place,
- (and DE_BARRIER_IN_NEXT_EPOCH_ISSUED in the previous Epoch)
- so that we can finish that epoch in drbd_may_finish_epoch().
- That is necessary if we already have a long chain of Epochs, before
- we realize that REQ_HARDBARRIER is actually not supported */
-
- /* As long as the -ENOTSUPP on the barrier is reported immediately
- that will never trigger. If it is reported late, we will just
- print that warning and continue correctly for all future requests
- with WO_bdev_flush */
- if (previous_epoch(mdev, e->epoch))
- dev_warn(DEV, "Write ordering was not enforced (one time event)\n");
-
- /* we still have a local reference,
- * get_ldev was done in receive_Data. */
-
- e->w.cb = e_end_block;
- if (drbd_submit_ee(mdev, e, WRITE, DRBD_FAULT_DT_WR) != 0) {
- /* drbd_submit_ee fails for one reason only:
- * if was not able to allocate sufficient bios.
- * requeue, try again later. */
- e->w.cb = w_e_reissue;
- drbd_queue_work(&mdev->data.work, &e->w);
- }
- return 1;
-}
-
static int receive_Barrier(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned int data_size)
{
- int rv, issue_flush;
+ int rv;
struct p_barrier *p = &mdev->data.rbuf.barrier;
struct drbd_epoch *epoch;
@@ -1300,44 +1180,40 @@
* Therefore we must send the barrier_ack after the barrier request was
* completed. */
switch (mdev->write_ordering) {
- case WO_bio_barrier:
case WO_none:
if (rv == FE_RECYCLED)
return TRUE;
- break;
+
+ /* receiver context, in the writeout path of the other node.
+ * avoid potential distributed deadlock */
+ epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
+ if (epoch)
+ break;
+ else
+ dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
+ /* Fall through */
case WO_bdev_flush:
case WO_drain_io:
- if (rv == FE_STILL_LIVE) {
- set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &mdev->current_epoch->flags);
- drbd_wait_ee_list_empty(mdev, &mdev->active_ee);
- rv = drbd_flush_after_epoch(mdev, mdev->current_epoch);
- }
- if (rv == FE_RECYCLED)
- return TRUE;
-
- /* The asender will send all the ACKs and barrier ACKs out, since
- all EEs moved from the active_ee to the done_ee. We need to
- provide a new epoch object for the EEs that come in soon */
- break;
- }
-
- /* receiver context, in the writeout path of the other node.
- * avoid potential distributed deadlock */
- epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
- if (!epoch) {
- dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
- issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &mdev->current_epoch->flags);
drbd_wait_ee_list_empty(mdev, &mdev->active_ee);
- if (issue_flush) {
- rv = drbd_flush_after_epoch(mdev, mdev->current_epoch);
- if (rv == FE_RECYCLED)
- return TRUE;
+ drbd_flush(mdev);
+
+ if (atomic_read(&mdev->current_epoch->epoch_size)) {
+ epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
+ if (epoch)
+ break;
}
- drbd_wait_ee_list_empty(mdev, &mdev->done_ee);
+ epoch = mdev->current_epoch;
+ wait_event(mdev->ee_wait, atomic_read(&epoch->epoch_size) == 0);
+
+ D_ASSERT(atomic_read(&epoch->active) == 0);
+ D_ASSERT(epoch->flags == 0);
return TRUE;
+ default:
+ dev_err(DEV, "Strangeness in mdev->write_ordering %d\n", mdev->write_ordering);
+ return FALSE;
}
epoch->flags = 0;
@@ -1652,15 +1528,8 @@
{
struct drbd_epoch_entry *e = (struct drbd_epoch_entry *)w;
sector_t sector = e->sector;
- struct drbd_epoch *epoch;
int ok = 1, pcmd;
- if (e->flags & EE_IS_BARRIER) {
- epoch = previous_epoch(mdev, e->epoch);
- if (epoch)
- drbd_may_finish_epoch(mdev, epoch, EV_BARRIER_DONE + (cancel ? EV_CLEANUP : 0));
- }
-
if (mdev->net_conf->wire_protocol == DRBD_PROT_C) {
if (likely((e->flags & EE_WAS_ERROR) == 0)) {
pcmd = (mdev->state.conn >= C_SYNC_SOURCE &&
@@ -1817,27 +1686,6 @@
e->epoch = mdev->current_epoch;
atomic_inc(&e->epoch->epoch_size);
atomic_inc(&e->epoch->active);
-
- if (mdev->write_ordering == WO_bio_barrier && atomic_read(&e->epoch->epoch_size) == 1) {
- struct drbd_epoch *epoch;
- /* Issue a barrier if we start a new epoch, and the previous epoch
- was not a epoch containing a single request which already was
- a Barrier. */
- epoch = list_entry(e->epoch->list.prev, struct drbd_epoch, list);
- if (epoch == e->epoch) {
- set_bit(DE_CONTAINS_A_BARRIER, &e->epoch->flags);
- rw |= REQ_HARDBARRIER;
- e->flags |= EE_IS_BARRIER;
- } else {
- if (atomic_read(&epoch->epoch_size) > 1 ||
- !test_bit(DE_CONTAINS_A_BARRIER, &epoch->flags)) {
- set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags);
- set_bit(DE_CONTAINS_A_BARRIER, &e->epoch->flags);
- rw |= REQ_HARDBARRIER;
- e->flags |= EE_IS_BARRIER;
- }
- }
- }
spin_unlock(&mdev->epoch_lock);
dp_flags = be32_to_cpu(p->dp_flags);