From: NeilBrown <neilb@suse.de>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org,
Dan Williams <dan.j.williams@intel.com>
Subject: [PATCH 027 of 29] md: md: replace R5_WantPrexor with R5_WantDrain, add 'prexor' reconstruct_states
Date: Fri, 27 Jun 2008 16:52:18 +1000 [thread overview]
Message-ID: <1080627065218.10761@suse.de> (raw)
In-Reply-To: 20080627164503.9671.patches@notabene
From: Dan Williams <dan.j.williams@intel.com>
Currently ops_run_biodrain and other locations have extra logic to determine
which blocks are processed in the prexor and non-prexor cases. This can be
eliminated if handle_write_operations5 flags the blocks to be processed in all
cases via R5_Wantdrain. The presence of the prexor operation is tracked in
sh->reconstruct_state.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
### Diffstat output
./drivers/md/raid5.c | 89 ++++++++++++++-----------------------------
./include/linux/raid/raid5.h | 6 +-
2 files changed, 32 insertions(+), 63 deletions(-)
diff .prev/drivers/md/raid5.c ./drivers/md/raid5.c
--- .prev/drivers/md/raid5.c 2008-06-27 16:42:36.000000000 +1000
+++ ./drivers/md/raid5.c 2008-06-27 16:42:56.000000000 +1000
@@ -637,7 +637,7 @@ ops_run_prexor(struct stripe_head *sh, s
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
/* Only process blocks that are known to be uptodate */
- if (dev->towrite && test_bit(R5_Wantprexor, &dev->flags))
+ if (test_bit(R5_Wantdrain, &dev->flags))
xor_srcs[count++] = dev->page;
}
@@ -649,16 +649,10 @@ ops_run_prexor(struct stripe_head *sh, s
}
static struct dma_async_tx_descriptor *
-ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx,
- unsigned long ops_request)
+ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
{
int disks = sh->disks;
- int pd_idx = sh->pd_idx, i;
-
- /* check if prexor is active which means only process blocks
- * that are part of a read-modify-write (Wantprexor)
- */
- int prexor = test_bit(STRIPE_OP_PREXOR, &ops_request);
+ int i;
pr_debug("%s: stripe %llu\n", __func__,
(unsigned long long)sh->sector);
@@ -666,20 +660,8 @@ ops_run_biodrain(struct stripe_head *sh,
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
struct bio *chosen;
- int towrite;
- towrite = 0;
- if (prexor) { /* rmw */
- if (dev->towrite &&
- test_bit(R5_Wantprexor, &dev->flags))
- towrite = 1;
- } else { /* rcw */
- if (i != pd_idx && dev->towrite &&
- test_bit(R5_LOCKED, &dev->flags))
- towrite = 1;
- }
-
- if (towrite) {
+ if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) {
struct bio *wbi;
spin_lock(&sh->lock);
@@ -704,18 +686,6 @@ ops_run_biodrain(struct stripe_head *sh,
static void ops_complete_postxor(void *stripe_head_ref)
{
struct stripe_head *sh = stripe_head_ref;
-
- pr_debug("%s: stripe %llu\n", __func__,
- (unsigned long long)sh->sector);
-
- sh->reconstruct_state = reconstruct_state_result;
- set_bit(STRIPE_HANDLE, &sh->state);
- release_stripe(sh);
-}
-
-static void ops_complete_write(void *stripe_head_ref)
-{
- struct stripe_head *sh = stripe_head_ref;
int disks = sh->disks, i, pd_idx = sh->pd_idx;
pr_debug("%s: stripe %llu\n", __func__,
@@ -727,14 +697,21 @@ static void ops_complete_write(void *str
set_bit(R5_UPTODATE, &dev->flags);
}
- sh->reconstruct_state = reconstruct_state_drain_result;
+ if (sh->reconstruct_state == reconstruct_state_drain_run)
+ sh->reconstruct_state = reconstruct_state_drain_result;
+ else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run)
+ sh->reconstruct_state = reconstruct_state_prexor_drain_result;
+ else {
+ BUG_ON(sh->reconstruct_state != reconstruct_state_run);
+ sh->reconstruct_state = reconstruct_state_result;
+ }
+
set_bit(STRIPE_HANDLE, &sh->state);
release_stripe(sh);
}
static void
-ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx,
- unsigned long ops_request)
+ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
{
/* kernel stack size limits the total number of disks */
int disks = sh->disks;
@@ -742,9 +719,8 @@ ops_run_postxor(struct stripe_head *sh,
int count = 0, pd_idx = sh->pd_idx, i;
struct page *xor_dest;
- int prexor = test_bit(STRIPE_OP_PREXOR, &ops_request);
+ int prexor = 0;
unsigned long flags;
- dma_async_tx_callback callback;
pr_debug("%s: stripe %llu\n", __func__,
(unsigned long long)sh->sector);
@@ -752,7 +728,8 @@ ops_run_postxor(struct stripe_head *sh,
/* check if prexor is active which means only process blocks
* that are part of a read-modify-write (written)
*/
- if (prexor) {
+ if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
+ prexor = 1;
xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
@@ -768,10 +745,6 @@ ops_run_postxor(struct stripe_head *sh,
}
}
- /* check whether this postxor is part of a write */
- callback = test_bit(STRIPE_OP_BIODRAIN, &ops_request) ?
- ops_complete_write : ops_complete_postxor;
-
/* 1/ if we prexor'd then the dest is reused as a source
* 2/ if we did not prexor then we are redoing the parity
* set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
@@ -785,10 +758,10 @@ ops_run_postxor(struct stripe_head *sh,
if (unlikely(count == 1)) {
flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST);
tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE,
- flags, tx, callback, sh);
+ flags, tx, ops_complete_postxor, sh);
} else
tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
- flags, tx, callback, sh);
+ flags, tx, ops_complete_postxor, sh);
}
static void ops_complete_check(void *stripe_head_ref)
@@ -847,12 +820,12 @@ static void raid5_run_ops(struct stripe_
tx = ops_run_prexor(sh, tx);
if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) {
- tx = ops_run_biodrain(sh, tx, ops_request);
+ tx = ops_run_biodrain(sh, tx);
overlap_clear++;
}
if (test_bit(STRIPE_OP_POSTXOR, &ops_request))
- ops_run_postxor(sh, tx, ops_request);
+ ops_run_postxor(sh, tx);
if (test_bit(STRIPE_OP_CHECK, &ops_request))
ops_run_check(sh);
@@ -1669,6 +1642,7 @@ handle_write_operations5(struct stripe_h
if (dev->towrite) {
set_bit(R5_LOCKED, &dev->flags);
+ set_bit(R5_Wantdrain, &dev->flags);
if (!expand)
clear_bit(R5_UPTODATE, &dev->flags);
s->locked++;
@@ -1681,7 +1655,7 @@ handle_write_operations5(struct stripe_h
BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) ||
test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags)));
- sh->reconstruct_state = reconstruct_state_drain_run;
+ sh->reconstruct_state = reconstruct_state_prexor_drain_run;
set_bit(STRIPE_OP_PREXOR, &s->ops_request);
set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
set_bit(STRIPE_OP_POSTXOR, &s->ops_request);
@@ -1691,15 +1665,10 @@ handle_write_operations5(struct stripe_h
if (i == pd_idx)
continue;
- /* For a read-modify write there may be blocks that are
- * locked for reading while others are ready to be
- * written so we distinguish these blocks by the
- * R5_Wantprexor bit
- */
if (dev->towrite &&
(test_bit(R5_UPTODATE, &dev->flags) ||
- test_bit(R5_Wantcompute, &dev->flags))) {
- set_bit(R5_Wantprexor, &dev->flags);
+ test_bit(R5_Wantcompute, &dev->flags))) {
+ set_bit(R5_Wantdrain, &dev->flags);
set_bit(R5_LOCKED, &dev->flags);
clear_bit(R5_UPTODATE, &dev->flags);
s->locked++;
@@ -2660,11 +2629,11 @@ static void handle_stripe5(struct stripe
* completed
*/
prexor = 0;
- if (sh->reconstruct_state == reconstruct_state_drain_result) {
+ if (sh->reconstruct_state == reconstruct_state_prexor_drain_result)
+ prexor = 1;
+ if (sh->reconstruct_state == reconstruct_state_drain_result ||
+ sh->reconstruct_state == reconstruct_state_prexor_drain_result) {
sh->reconstruct_state = reconstruct_state_idle;
- for (i = disks; i--; )
- prexor += test_and_clear_bit(R5_Wantprexor,
- &sh->dev[i].flags);
/* All the 'written' buffers and the parity block are ready to
* be written back to disk
diff .prev/include/linux/raid/raid5.h ./include/linux/raid/raid5.h
--- .prev/include/linux/raid/raid5.h 2008-06-27 16:42:36.000000000 +1000
+++ ./include/linux/raid/raid5.h 2008-06-27 16:42:56.000000000 +1000
@@ -187,8 +187,10 @@ enum check_states {
*/
enum reconstruct_states {
reconstruct_state_idle = 0,
+ reconstruct_state_prexor_drain_run, /* prexor-write */
reconstruct_state_drain_run, /* write */
reconstruct_state_run, /* expand */
+ reconstruct_state_prexor_drain_result,
reconstruct_state_drain_result,
reconstruct_state_result,
};
@@ -258,9 +260,7 @@ struct r6_state {
#define R5_Wantfill 12 /* dev->toread contains a bio that needs
* filling
*/
-#define R5_Wantprexor 13 /* distinguish blocks ready for rmw from
- * other "towrites"
- */
+#define R5_Wantdrain 13 /* dev->towrite needs to be drained */
/*
* Write method
*/
next prev parent reply other threads:[~2008-06-27 6:52 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-27 6:49 [PATCH 000 of 29] md: Introduction : patchbomb for 2.6.27 merge window NeilBrown
2008-06-27 6:49 ` [PATCH 001 of 29] md: Ensure interrupted recovery completed properly (v1 metadata plus bitmap) NeilBrown
2008-07-01 7:20 ` Jan Engelhardt
2008-06-27 6:49 ` [PATCH 002 of 29] md: Don't acknowlege that stripe-expand is complete until it really is NeilBrown
2008-06-27 6:49 ` [PATCH 003 of 29] md: Fix error paths if md_probe fails NeilBrown
2008-06-27 6:49 ` [PATCH 004 of 29] md: linear: correct disk numbering error check NeilBrown
2008-06-27 6:49 ` [PATCH 005 of 29] md: use bio_endio instead of a call to bi_end_io NeilBrown
2008-06-27 6:49 ` [PATCH 006 of 29] md: Improve setting of "events_cleared" for write-intent bitmaps NeilBrown
2008-06-27 6:50 ` [PATCH 007 of 29] md: Allow setting start point for requested check/repair NeilBrown
2008-06-27 6:50 ` [PATCH 008 of 29] md: Close race in md_probe NeilBrown
2008-06-27 12:21 ` Andre Noll
2008-06-27 23:38 ` Neil Brown
2008-06-30 7:52 ` Andre Noll
2008-06-27 6:50 ` [PATCH 009 of 29] md: Don't try to make md arrays dirty if that is not meaningful NeilBrown
2008-06-27 6:50 ` [PATCH 010 of 29] md: Enable setting of 'offset' and 'size' of a hot-added spare NeilBrown
2008-06-27 6:50 ` [PATCH 011 of 29] md: Support adding a spare to a live md array with external metadata NeilBrown
2008-06-27 6:50 ` [PATCH 012 of 29] md: rationalise return value for ->hot_add_disk method NeilBrown
2008-06-27 6:50 ` [PATCH 013 of 29] md: Don't reject HOT_REMOVE_DISK request for an array that is not yet started NeilBrown
2008-06-27 6:50 ` [PATCH 014 of 29] md: Make sure all changes to md/array_state are notified NeilBrown
2008-06-27 6:50 ` [PATCH 015 of 29] md: Make sure all changes to md/sync_action " NeilBrown
2008-06-27 6:51 ` [PATCH 016 of 29] md: Make sure all changes to md/degraded " NeilBrown
2008-06-27 6:51 ` [PATCH 017 of 29] md: Make sure all changes to md/dev-XX/state " NeilBrown
2008-06-27 6:51 ` [PATCH 018 of 29] md: Support changing rdev size on running arrays NeilBrown
2008-06-27 16:09 ` Markus Hochholdinger
2008-06-27 23:41 ` Neil Brown
2010-03-30 14:52 ` Markus Hochholdinger
2010-03-31 5:41 ` Neil Brown
2010-04-01 15:23 ` Markus Hochholdinger
2012-03-24 20:47 ` Markus Hochholdinger
2012-03-25 22:15 ` NeilBrown
2021-11-10 13:09 ` Markus Hochholdinger
2021-11-10 17:51 ` Markus Hochholdinger
2021-11-11 13:10 ` Markus Hochholdinger
2021-11-11 15:09 ` Markus Hochholdinger
2021-11-12 1:22 ` Guoqing Jiang
2021-11-12 14:31 ` Markus Hochholdinger
2008-06-27 6:51 ` [PATCH 019 of 29] md: md: kill STRIPE_OP_MOD_DMA in raid5 offload NeilBrown
2008-06-27 6:51 ` [PATCH 020 of 29] md: md: kill STRIPE_OP_IO flag NeilBrown
2008-06-27 6:51 ` [PATCH 021 of 29] md: md: use stripe_head_state in ops_run_io() NeilBrown
2008-06-27 6:51 ` [PATCH 022 of 29] md: md: unify raid5/6 i/o submission NeilBrown
2008-06-27 6:51 ` [PATCH 023 of 29] md: md: replace STRIPE_OP_CHECK with 'check_states' NeilBrown
2008-06-27 6:51 ` [PATCH 024 of 29] md: md: replace STRIPE_OP_BIOFILL with STRIPE_BIOFILL_RUN NeilBrown
2008-06-27 6:52 ` [PATCH 025 of 29] md: md: replace STRIPE_OP_COMPUTE_BLK with STRIPE_COMPUTE_RUN NeilBrown
2008-06-27 6:52 ` [PATCH 026 of 29] md: md: replace STRIPE_OP_{BIODRAIN,PREXOR,POSTXOR} with 'reconstruct_states' NeilBrown
2008-06-27 6:52 ` NeilBrown [this message]
2008-06-27 6:52 ` [PATCH 028 of 29] md: md: handle operation chaining in raid5_run_ops NeilBrown
2008-06-27 6:52 ` [PATCH 029 of 29] md: md: rationalize raid5 function names NeilBrown
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