From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Andreas Gruenbacher <agruenba@redhat.com>,
Barry Marson <bmarson@redhat.com>,
Mike Snitzer <snitzer@redhat.com>
Subject: [PATCH 5.6 27/29] Revert "dm: always call blk_queue_split() in dm_process_bio()"
Date: Tue, 7 Apr 2020 12:22:24 +0200 [thread overview]
Message-ID: <20200407101455.421449589@linuxfoundation.org> (raw)
In-Reply-To: <20200407101452.046058399@linuxfoundation.org>
From: Mike Snitzer <snitzer@redhat.com>
commit 120c9257f5f19e5d1e87efcbb5531b7cd81b7d74 upstream.
This reverts commit effd58c95f277744f75d6e08819ac859dbcbd351.
blk_queue_split() is causing excessive IO splitting -- because
blk_max_size_offset() depends on 'chunk_sectors' limit being set and
if it isn't (as is the case for DM targets!) it falls back to
splitting on a 'max_sectors' boundary regardless of offset.
"Fix" this by reverting back to _not_ using blk_queue_split() in
dm_process_bio() for normal IO (reads and writes). Long-term fix is
still TBD but it should focus on training blk_max_size_offset() to
call into a DM provided hook (to call DM's max_io_len()).
Test results from simple misaligned IO test on 4-way dm-striped device
with chunksize of 128K and stripesize of 512K:
xfs_io -d -c 'pread -b 2m 224s 4072s' /dev/mapper/stripe_dev
before this revert:
253,0 21 1 0.000000000 2206 Q R 224 + 4072 [xfs_io]
253,0 21 2 0.000008267 2206 X R 224 / 480 [xfs_io]
253,0 21 3 0.000010530 2206 X R 224 / 256 [xfs_io]
253,0 21 4 0.000027022 2206 X R 480 / 736 [xfs_io]
253,0 21 5 0.000028751 2206 X R 480 / 512 [xfs_io]
253,0 21 6 0.000033323 2206 X R 736 / 992 [xfs_io]
253,0 21 7 0.000035130 2206 X R 736 / 768 [xfs_io]
253,0 21 8 0.000039146 2206 X R 992 / 1248 [xfs_io]
253,0 21 9 0.000040734 2206 X R 992 / 1024 [xfs_io]
253,0 21 10 0.000044694 2206 X R 1248 / 1504 [xfs_io]
253,0 21 11 0.000046422 2206 X R 1248 / 1280 [xfs_io]
253,0 21 12 0.000050376 2206 X R 1504 / 1760 [xfs_io]
253,0 21 13 0.000051974 2206 X R 1504 / 1536 [xfs_io]
253,0 21 14 0.000055881 2206 X R 1760 / 2016 [xfs_io]
253,0 21 15 0.000057462 2206 X R 1760 / 1792 [xfs_io]
253,0 21 16 0.000060999 2206 X R 2016 / 2272 [xfs_io]
253,0 21 17 0.000062489 2206 X R 2016 / 2048 [xfs_io]
253,0 21 18 0.000066133 2206 X R 2272 / 2528 [xfs_io]
253,0 21 19 0.000067507 2206 X R 2272 / 2304 [xfs_io]
253,0 21 20 0.000071136 2206 X R 2528 / 2784 [xfs_io]
253,0 21 21 0.000072764 2206 X R 2528 / 2560 [xfs_io]
253,0 21 22 0.000076185 2206 X R 2784 / 3040 [xfs_io]
253,0 21 23 0.000077486 2206 X R 2784 / 2816 [xfs_io]
253,0 21 24 0.000080885 2206 X R 3040 / 3296 [xfs_io]
253,0 21 25 0.000082316 2206 X R 3040 / 3072 [xfs_io]
253,0 21 26 0.000085788 2206 X R 3296 / 3552 [xfs_io]
253,0 21 27 0.000087096 2206 X R 3296 / 3328 [xfs_io]
253,0 21 28 0.000093469 2206 X R 3552 / 3808 [xfs_io]
253,0 21 29 0.000095186 2206 X R 3552 / 3584 [xfs_io]
253,0 21 30 0.000099228 2206 X R 3808 / 4064 [xfs_io]
253,0 21 31 0.000101062 2206 X R 3808 / 3840 [xfs_io]
253,0 21 32 0.000104956 2206 X R 4064 / 4096 [xfs_io]
253,0 21 33 0.001138823 0 C R 4096 + 200 [0]
after this revert:
253,0 18 1 0.000000000 4430 Q R 224 + 3896 [xfs_io]
253,0 18 2 0.000018359 4430 X R 224 / 256 [xfs_io]
253,0 18 3 0.000028898 4430 X R 256 / 512 [xfs_io]
253,0 18 4 0.000033535 4430 X R 512 / 768 [xfs_io]
253,0 18 5 0.000065684 4430 X R 768 / 1024 [xfs_io]
253,0 18 6 0.000091695 4430 X R 1024 / 1280 [xfs_io]
253,0 18 7 0.000098494 4430 X R 1280 / 1536 [xfs_io]
253,0 18 8 0.000114069 4430 X R 1536 / 1792 [xfs_io]
253,0 18 9 0.000129483 4430 X R 1792 / 2048 [xfs_io]
253,0 18 10 0.000136759 4430 X R 2048 / 2304 [xfs_io]
253,0 18 11 0.000152412 4430 X R 2304 / 2560 [xfs_io]
253,0 18 12 0.000160758 4430 X R 2560 / 2816 [xfs_io]
253,0 18 13 0.000183385 4430 X R 2816 / 3072 [xfs_io]
253,0 18 14 0.000190797 4430 X R 3072 / 3328 [xfs_io]
253,0 18 15 0.000197667 4430 X R 3328 / 3584 [xfs_io]
253,0 18 16 0.000218751 4430 X R 3584 / 3840 [xfs_io]
253,0 18 17 0.000226005 4430 X R 3840 / 4096 [xfs_io]
253,0 18 18 0.000250404 4430 Q R 4120 + 176 [xfs_io]
253,0 18 19 0.000847708 0 C R 4096 + 24 [0]
253,0 18 20 0.000855783 0 C R 4120 + 176 [0]
Fixes: effd58c95f27774 ("dm: always call blk_queue_split() in dm_process_bio()")
Cc: stable@vger.kernel.org
Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Tested-by: Barry Marson <bmarson@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/md/dm.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1739,8 +1739,9 @@ static blk_qc_t dm_process_bio(struct ma
* won't be imposed.
*/
if (current->bio_list) {
- blk_queue_split(md->queue, &bio);
- if (!is_abnormal_io(bio))
+ if (is_abnormal_io(bio))
+ blk_queue_split(md->queue, &bio);
+ else
dm_queue_split(md, ti, &bio);
}
next prev parent reply other threads:[~2020-04-07 10:27 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-07 10:21 [PATCH 5.6 00/29] 5.6.3-rc1 review Greg Kroah-Hartman
2020-04-07 10:21 ` [PATCH 5.6 01/29] ipv4: fix a RCU-list lock in fib_triestat_seq_show Greg Kroah-Hartman
2020-04-07 10:21 ` [PATCH 5.6 02/29] net: dsa: ksz: Select KSZ protocol tag Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 03/29] net, ip_tunnel: fix interface lookup with no key Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 04/29] sctp: fix possibly using a bad saddr with a given dst Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 05/29] sctp: fix refcount bug in sctp_wfree Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 06/29] net: macb: Fix handling of fixed-link node Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 07/29] net: fix fraglist segmentation reference count leak Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 08/29] udp: initialize is_flist with 0 in udp_gro_receive Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 09/29] padata: fix uninitialized return value in padata_replace() Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 10/29] brcmfmac: abort and release host after error Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 11/29] bpf: Fix tnum constraints for 32-bit comparisons Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 12/29] XArray: Fix xa_find_next for large multi-index entries Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 13/29] drm/bridge: analogix-anx6345: Avoid duplicate -supply suffix Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 14/29] drm/i915/display: Fix mode private_flags comparison at atomic_check Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 15/29] misc: rtsx: set correct pcr_ops for rts522A Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 16/29] misc: pci_endpoint_test: Fix to support > 10 pci-endpoint-test devices Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 17/29] misc: pci_endpoint_test: Avoid using module parameter to determine irqtype Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 18/29] PCI: sysfs: Revert "rescan" file renames Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 19/29] coresight: do not use the BIT() macro in the UAPI header Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 20/29] mei: me: add cedar fork device ids Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 21/29] nvmem: release the write-protect pin Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 22/29] nvmem: check for NULL reg_read and reg_write before dereferencing Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 23/29] nvmem: sprd: Fix the block lock operation Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 24/29] extcon: axp288: Add wakeup support Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 25/29] power: supply: axp288_charger: Add special handling for HP Pavilion x2 10 Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 26/29] Revert "ALSA: uapi: Drop asound.h inclusion from asoc.h" Greg Kroah-Hartman
2020-04-07 10:22 ` Greg Kroah-Hartman [this message]
2020-04-07 10:22 ` [PATCH 5.6 28/29] ALSA: hda/ca0132 - Add Recon3Di quirk to handle integrated sound on EVGA X99 Classified motherboard Greg Kroah-Hartman
2020-04-07 10:22 ` [PATCH 5.6 29/29] soc: mediatek: knows_txdone needs to be set in Mediatek CMDQ helper Greg Kroah-Hartman
2020-04-07 12:37 ` [PATCH 5.6 00/29] 5.6.3-rc1 review Jon Hunter
2020-04-07 12:37 ` Jon Hunter
[not found] ` <dd65ddb4-478c-c022-542c-5e0b44ab8962-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
2020-04-07 14:49 ` Greg Kroah-Hartman
2020-04-07 14:49 ` Greg Kroah-Hartman
2020-04-07 13:51 ` Daniel Díaz
2020-04-07 14:43 ` Greg Kroah-Hartman
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