linux/drivers
Venki Pallipadi bde6f5f59c x86: voluntary leave_mm before entering ACPI C3
Aviod TLB flush IPIs during C3 states by voluntary leave_mm()
before entering C3.

The performance impact of TLB flush on C3 should not be significant with
respect to C3 wakeup latency. Also, CPUs tend to flush TLB in hardware while in
C3 anyways.

On a 8 logical CPU system, running make -j2, the number of tlbflush IPIs goes
down from 40 per second to ~ 0. Total number of interrupts during the run
of this workload was ~1200 per second, which makes it ~3% savings in wakeups.

There was no measurable performance or power impact however.

[ akpm@linux-foundation.org: symbol export fixes. ]

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:32:01 +01:00
..
acorn/char
acpi x86: voluntary leave_mm before entering ACPI C3 2008-01-30 13:32:01 +01:00
amba
ata
atm
auxdisplay
base
block cciss: fix bug in overriding ->data_len before completion 2008-01-29 21:55:18 +01:00
bluetooth
cdrom
char x86: clean up drivers/char/rtc.c 2008-01-30 13:31:09 +01:00
clocksource
connector
cpufreq
cpuidle
crypto
dca
dio
dma
edac
eisa
firewire
firmware x86: fix DMI out of memory problems 2008-01-30 13:31:59 +01:00
hid
hwmon
i2c
ide
ieee1394
infiniband Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.25 2008-01-29 22:54:01 +11:00
input x86: replace outb_p() with udelay(2) in drivers/input/mouse/pc110pad.c 2008-01-30 13:31:24 +01:00
isdn
kvm x86: get rid of _MASK flags 2008-01-30 13:31:27 +01:00
leds
lguest x86: use generic register name in the thread and tss structures 2008-01-30 13:31:02 +01:00
macintosh
mca
md
media
message
mfd
misc
mmc
mtd
net Mostly revert "e1000/e1000e: Move PCI-Express device IDs over to e1000e" 2008-01-30 09:54:54 +11:00
nubus
of
oprofile
parisc
parport
pci
pcmcia
pnp
power
ps3
rapidio
rtc
s390
sbus
scsi
serial
sh
sn
spi
ssb
tc
telephony
uio
usb
video
virtio
w1
watchdog
xen
zorro
Kconfig
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