linux_dsm_epyc7002/include
Michal Kubeček 2ac3ac8f86 ipv6: prevent fib6_run_gc() contention
On a high-traffic router with many processors and many IPv6 dst
entries, soft lockup in fib6_run_gc() can occur when number of
entries reaches gc_thresh.

This happens because fib6_run_gc() uses fib6_gc_lock to allow
only one thread to run the garbage collector but ip6_dst_gc()
doesn't update net->ipv6.ip6_rt_last_gc until fib6_run_gc()
returns. On a system with many entries, this can take some time
so that in the meantime, other threads pass the tests in
ip6_dst_gc() (ip6_rt_last_gc is still not updated) and wait for
the lock. They then have to run the garbage collector one after
another which blocks them for quite long.

Resolve this by replacing special value ~0UL of expire parameter
to fib6_run_gc() by explicit "force" parameter to choose between
spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with
force=false if gc_thresh is reached but not max_size.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01 14:16:20 -07:00
..
acpi Revert "ACPI / video / i915: No ACPI backlight if firmware expects Windows 8" 2013-07-26 14:59:20 +02:00
asm-generic Merge branch 'cpuinit-delete' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2013-07-07 11:01:19 -07:00
clocksource
crypto
drm drm/cma: remove GEM CMA specific dma_buf functionality 2013-07-05 15:44:54 +10:00
dt-bindings Pin control fixes for the v3.11 series: 2013-07-28 18:19:27 -07:00
keys
kvm ARM: KVM: Allow host virt timer irq to be different from guest timer virt irq 2013-06-26 10:50:02 -07:00
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-07-31 12:56:18 -07:00
math-emu
media [media] exynos4-is: Correct colorspace handling at FIMC-LITE 2013-06-28 15:33:27 -03:00
memory
misc
net ipv6: prevent fib6_run_gc() contention 2013-08-01 14:16:20 -07:00
pcmcia
ras
rdma Merge branches 'af_ib', 'cxgb4', 'misc', 'mlx5', 'ocrdma', 'qib' and 'srp' into for-next 2013-07-08 11:22:11 -07:00
rxrpc
scsi [SCSI] libiscsi: Added new boot entries in the session sysfs 2013-06-26 18:04:11 -07:00
sound ASoC: More updates for v3.11 2013-06-28 13:36:22 +02:00
target target: make queue_tm_rsp() return void 2013-07-07 18:36:53 -07:00
trace This contains fixes, optimizations and some clean ups 2013-07-22 19:07:24 -07:00
uapi Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem 2013-08-01 14:30:59 -04:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-07-09 16:04:31 -07:00
xen Merge branch 'for-3.11/drivers' of git://git.kernel.dk/linux-block 2013-07-22 19:02:52 -07:00
Kbuild