James Wang 6460495709 Fix loop device flush before configure v3 ... While installing SLES-12 (based on v4.4), I found that the installer will stall for 60+ seconds during LVM disk scan. The root cause was determined to be the removal of a bound device check in loop_flush() by commit b5dd2f6047 ("block: loop: improve performance via blk-mq"). Restoring this check, examining ->lo_state as set by loop_set_fd() eliminates the bad behavior. Test method: modprobe loop max_loop=64 dd if=/dev/zero of=disk bs=512 count=200K for((i=0;i<4;i++))do losetup -f disk; done mkfs.ext4 -F /dev/loop0 for((i=0;i<4;i++))do mkdir t$i; mount /dev/loop$i t$i;done for f in `ls /dev/loop[0-9]*|sort`; do \ echo $f; dd if=$f of=/dev/null bs=512 count=1; \ done Test output: stock patched /dev/loop0 18.1217e-05 8.3842e-05 /dev/loop1 6.1114e-05 0.000147979 /dev/loop10 0.414701 0.000116564 /dev/loop11 0.7474 6.7942e-05 /dev/loop12 0.747986 8.9082e-05 /dev/loop13 0.746532 7.4799e-05 /dev/loop14 0.480041 9.3926e-05 /dev/loop15 1.26453 7.2522e-05 Note that from loop10 onward, the device is not mounted, yet the stock kernel consumes several orders of magnitude more wall time than it does for a mounted device. (Thanks for Mike Galbraith <efault@gmx.de>, give a changelog review.) Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: James Wang <jnwang@suse.com> Fixes: b5dd2f6047 ("block: loop: improve performance via blk-mq") Signed-off-by: Jens Axboe <axboe@fb.com>		2017-06-08 08:04:18 -06:00
..
aoe
drbd	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2017-05-20 16:12:30 -07:00
mtip32xx	mtip32xx: convert internal commands to regular block infrastructure	2017-05-03 08:09:19 -06:00
paride	pd: don't check blk_execute_rq return value.	2017-04-20 12:16:10 -06:00
rsxx
xen-blkback	block: xen-blkback: add null check to avoid null pointer dereference	2017-05-15 17:14:28 -04:00
zram	zram: reduce load operation in page_same_filled	2017-05-03 15:52:11 -07:00
amiflop.c
ataflop.c	ataflop: switch from req->errors to req->error_count	2017-04-20 12:16:10 -06:00
brd.c	libnvdimm for 4.12	2017-05-05 18:49:20 -07:00
cciss_cmd.h
cciss_scsi.c
cciss_scsi.h
cciss.c	scsi: introduce a result field in struct scsi_request	2017-04-20 12:16:10 -06:00
cciss.h
cryptoloop.c
DAC960.c
DAC960.h
floppy.c	floppy: switch from req->errors to req->error_count	2017-04-20 12:16:10 -06:00
Kconfig	libnvdimm for 4.12	2017-05-05 18:49:20 -07:00
loop.c	Fix loop device flush before configure v3	2017-06-08 08:04:18 -06:00
loop.h	loop: zero-fill bio on the submitting cpu	2017-04-20 12:16:10 -06:00
Makefile
nbd.c	nbd: don't leak nbd_config	2017-05-30 08:15:08 -06:00
null_blk.c	blk-mq: remove the error argument to blk_mq_complete_request	2017-04-20 12:16:10 -06:00
pktcdvd.c	scsi: introduce a result field in struct scsi_request	2017-04-20 12:16:10 -06:00
ps3disk.c
ps3vram.c
rbd_types.h
rbd.c	rbd: implement REQ_OP_WRITE_ZEROES	2017-05-29 11:18:01 +02:00
skd_main.c
skd_s1120.h
smart1,2.h
sunvdc.c
swim3.c	swim3: remove (commented out) printing of req->errors	2017-04-20 12:16:10 -06:00
swim_asm.S
swim.c
sx8.c
umem.c
umem.h
virtio_blk.c	virtio: fixes, cleanups, performance	2017-05-10 11:33:08 -07:00
xen-blkfront.c	blk-mq: remove the error argument to blk_mq_complete_request	2017-04-20 12:16:10 -06:00
xsysace.c
z2ram.c