linux-uconsole/include
Peter Zijlstra 38ff667b32 perf_counter: fix update_userpage()
It just occured to me it is possible to have multiple contending
updates of the userpage (mmap information vs overflow vs counter).
This would break the seqlock logic.

It appear the arch code uses this from NMI context, so we cannot
possibly serialize its use, therefore separate the data_head update
from it and let it return to its original use.

The arch code needs to make sure there are no contending callers by
disabling the counter before using it -- powerpc appears to do this
nicely.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Orig-LKML-Reference: <20090330171023.241410660@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-06 09:30:37 +02:00
..
acpi ACPI: support acpi_device_ops .notify methods 2009-04-05 02:25:07 -04:00
asm-arm
asm-frv Merge branch 'tracing/core-v2' into tracing-for-linus 2009-04-02 00:49:02 +02:00
asm-generic Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
asm-h8300
asm-m32r Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
asm-mn10300 Merge branch 'tracing/core-v2' into tracing-for-linus 2009-04-02 00:49:02 +02:00
crypto
drm drm: remove unused "can_grow" parameter from drm_crtc_helper_initial_config 2009-04-03 10:21:44 +10:00
keys
linux perf_counter: fix update_userpage() 2009-04-06 09:30:37 +02:00
math-emu
media V4L/DVB (11313): v4l2-subdev: add enum_framesizes and enum_frameintervals. 2009-03-30 12:43:49 -03:00
mtd
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2009-04-02 21:05:30 -07:00
pcmcia
rdma
rxrpc
scsi
sound V4L/DVB (10771): tea575x-tuner: convert it to V4L2 API 2009-03-30 12:43:02 -03:00
trace tracing, net: fix net tree and tracing tree merge interaction 2009-04-02 00:50:30 +02:00
video fbdev: update s1d13xxxfb to differ between revisions and production ids 2009-04-01 08:59:32 -07:00
xen
Kbuild