kernel_optimize_test/drivers/s390
Rusty Russell 7b21e34fd1 virtio: harsher barriers for rpmsg.
We were cheating with our barriers; using the smp ones rather than the
real device ones.  That was fine, until rpmsg came along, which is
used to talk to a real device (a non-SMP CPU).

Unfortunately, just putting back the real barriers (reverting
d57ed95d) causes a performance regression on virtio-pci.  In
particular, Amos reports netbench's TCP_RR over virtio_net CPU
utilization increased up to 35% while throughput went down by up to
14%.

By comparison, this branch is in the noise.

Reference: https://lkml.org/lkml/2011/12/11/22

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-12 15:44:42 +10:30
..
block Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-01-09 08:11:13 -08:00
char Merge branch 'char-misc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc 2012-01-09 12:08:59 -08:00
cio [S390] qdio: fix kernel panic for zfcp 31-bit 2011-12-27 11:27:14 +01:00
crypto [S390] zcrypt: Fix error return codes. 2011-12-27 11:27:13 +01:00
kvm virtio: harsher barriers for rpmsg. 2012-01-12 15:44:42 +10:30
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-01-09 08:11:13 -08:00
scsi [SCSI] zfcp: return early from slave_destroy if slave_alloc returned early 2011-12-14 15:40:43 +04:00
Makefile [S390] split/move machine check handler code 2009-03-26 15:24:10 +01:00