Nick Piggin 35a82d1a53 [PATCH] optimise loop driver a bit ... Looks like locking can be optimised quite a lot. Increase lock widths slightly so lo_lock is taken fewer times per request. Also it was quite trivial to cover lo_pending with that lock, and remove the atomic requirement. This also makes memory ordering explicitly correct, which is nice (not that I particularly saw any mem ordering bugs). Test was reading 4 250MB files in parallel on ext2-on-tmpfs filesystem (1K block size, 4K page size). System is 2 socket Xeon with HT (4 thread). intel:/home/npiggin# umount /dev/loop0 ; mount /dev/loop0 /mnt/loop ; /usr/bin/time ./mtloop.sh Before: 0.24user 5.51system 0:02.84elapsed 202%CPU (0avgtext+0avgdata 0maxresident)k 0.19user 5.52system 0:02.88elapsed 198%CPU (0avgtext+0avgdata 0maxresident)k 0.19user 5.57system 0:02.89elapsed 198%CPU (0avgtext+0avgdata 0maxresident)k 0.22user 5.51system 0:02.90elapsed 197%CPU (0avgtext+0avgdata 0maxresident)k 0.19user 5.44system 0:02.91elapsed 193%CPU (0avgtext+0avgdata 0maxresident)k After: 0.07user 2.34system 0:01.68elapsed 143%CPU (0avgtext+0avgdata 0maxresident)k 0.06user 2.37system 0:01.68elapsed 144%CPU (0avgtext+0avgdata 0maxresident)k 0.06user 2.39system 0:01.68elapsed 145%CPU (0avgtext+0avgdata 0maxresident)k 0.06user 2.36system 0:01.68elapsed 144%CPU (0avgtext+0avgdata 0maxresident)k 0.06user 2.42system 0:01.68elapsed 147%CPU (0avgtext+0avgdata 0maxresident)k Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>		2005-06-23 09:45:18 -07:00
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acorn
acpi
atm
base	[PATCH] driver core: Fix up the device_attach() error handling in bus_add_device()	2005-06-22 23:01:10 -07:00
block	[PATCH] optimise loop driver a bit	2005-06-23 09:45:18 -07:00
bluetooth
cdrom
char
cpufreq
crypto
dio
eisa
fc4
firmware
i2c	[PATCH] I2C: fix ds1374 build	2005-06-21 21:55:00 -07:00
ide	[PATCH] NUMA aware block device control structure allocation	2005-06-23 09:45:09 -07:00
ieee1394
infiniband
input
isdn
macintosh
mca
md	[PATCH] create a kstrdup library function	2005-06-23 09:45:18 -07:00
media
message
misc
mmc
mtd
net	Merge 'misc-fixes' branch of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6	2005-06-23 09:25:04 -07:00
nubus
oprofile
parisc
parport	[PATCH] create a kstrdup library function	2005-06-23 09:45:18 -07:00
pci
pcmcia
pnp
s390
sbus
scsi
serial
sh
sn
tc
telephony
usb	[PATCH] USB: fix hid core to return proper error code from probe	2005-06-22 23:01:09 -07:00
video
w1
zorro
Kconfig
Makefile