Linus Torvalds 9226b5b440 vfs: avoid non-forwarding large load after small store in path lookup ... The performance regression that Josef Bacik reported in the pathname lookup (see commit 99d263d4c5 "vfs: fix bad hashing of dentries") made me look at performance stability of the dcache code, just to verify that the problem was actually fixed. That turned up a few other problems in this area. There are a few cases where we exit RCU lookup mode and go to the slow serializing case when we shouldn't, Al has fixed those and they'll come in with the next VFS pull. But my performance verification also shows that link_path_walk() turns out to have a very unfortunate 32-bit store of the length and hash of the name we look up, followed by a 64-bit read of the combined hash_len field. That screws up the processor store to load forwarding, causing an unnecessary hickup in this critical routine. It's caused by the ugly calling convention for the "hash_name()" function, and easily fixed by just making hash_name() fill in the whole 'struct qstr' rather than passing it a pointer to just the hash value. With that, the profile for this function looks much smoother. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-09-14 17:28:32 -07:00
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acpi	ACPI / scan: not cache _SUN value in struct acpi_device_pnp	2014-09-03 22:41:14 +02:00
asm-generic
clocksource
crypto
drm
dt-bindings
keys
kvm
linux	vfs: avoid non-forwarding large load after small store in path lookup	2014-09-14 17:28:32 -07:00
math-emu
media
memory
misc
net	Merge tag 'master-2014-09-04' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless	2014-09-07 16:11:10 -07:00
pcmcia
ras
rdma
rxrpc
scsi
soc/tegra
sound
target
trace	net: treewide: Fix typo found in DocBook/networking.xml	2014-09-05 17:35:28 -07:00
uapi	USB fixes for 3.17-rc5	2014-09-12 11:59:10 -07:00
video
xen	xen/arm: introduce XENFEAT_grant_map_identity	2014-09-11 18:11:52 +00:00
Kbuild