]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
x86_64: Calgary - tighten up the bitmap locking
authorMuli Ben-Yehuda <muli@il.ibm.com>
Sat, 21 Jul 2007 15:11:04 +0000 (17:11 +0200)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 22 Jul 2007 01:37:11 +0000 (18:37 -0700)
commit820a149705c2c2a37989554a4f4a34e3d0b0df1f
treed6f13abb1b2640b598907c00d8eb4d2c17743b68
parent7354b07595b2e43b75fe353fcf18e73eb0427c9b
x86_64: Calgary - tighten up the bitmap locking

Currently the IOMMU table's lock protects both the bitmap and access
to the hardware's TCE table. Access to the TCE table is synchronized
through the bitmap; therefore, only hold the lock while modifying the
bitmap. This gives a yummy 10-15% reduction in CPU utilization for
netperf on a large SMP machine.

Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86_64/kernel/pci-calgary.c