Julian Anastasov bcbde4c0a7 ipvs: make the service replacement more robust ... commit 578bc3ef1e ("ipvs: reorganize dest trash") added IP_VS_DEST_STATE_REMOVING flag and RCU callback named ip_vs_dest_wait_readers() to keep dests and services after removal for at least a RCU grace period. But we have the following corner cases: - we can not reuse the same dest if its service is removed while IP_VS_DEST_STATE_REMOVING is still set because another dest removal in the first grace period can not extend this period. It can happen when ipvsadm -C && ipvsadm -R is used. - dest->svc can be replaced but ip_vs_in_stats() and ip_vs_out_stats() have no explicit read memory barriers when accessing dest->svc. It can happen that dest->svc was just freed (replaced) while we use it to update the stats. We solve the problems as follows: - IP_VS_DEST_STATE_REMOVING is removed and we ensure a fixed idle period for the dest (IP_VS_DEST_TRASH_PERIOD). idle_start will remember when for first time after deletion we noticed dest->refcnt=0. Later, the connections can grab a reference while in RCU grace period but if refcnt becomes 0 we can safely free the dest and its svc. - dest->svc becomes RCU pointer. As result, we add explicit RCU locking in ip_vs_in_stats() and ip_vs_out_stats(). - __ip_vs_unbind_svc is renamed to __ip_vs_svc_put(), it now can free the service immediately or after a RCU grace period. dest->svc is not set to NULL anymore. As result, unlinked dests and their services are freed always after IP_VS_DEST_TRASH_PERIOD period, unused services are freed after a RCU grace period. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Simon Horman <horms@verge.net.au>		2013-09-18 14:39:03 -05:00
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acpi
asm-generic	Merge branch 'for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping	2013-09-09 10:26:33 -07:00
clocksource	ARM: SoC cleanups for 3.12	2013-09-06 13:21:16 -07:00
crypto
drm	Merge tag 'drm-intel-fixes-2013-09-06' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes	2013-09-10 12:36:55 +10:00
dt-bindings	Device tree core updates for v3.12	2013-09-10 13:53:52 -07:00
keys
kvm
linux	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf	2013-09-17 20:22:53 -04:00
math-emu
media	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2013-09-05 14:54:29 -07:00
memory
misc
net	ipvs: make the service replacement more robust	2013-09-18 14:39:03 -05:00
pcmcia
ras
rdma	Merge branches 'cxgb4', 'flowsteer', 'ipoib', 'iser', 'mlx4', 'ocrdma' and 'qib' into for-next	2013-09-03 09:01:08 -07:00
rxrpc
scsi
sound	Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media	2013-09-05 11:55:59 -07:00
target
trace	mm/page_alloc.c: fix the value of fallback_migratetype in alloc_extfrag tracepoint()	2013-09-11 15:57:19 -07:00
uapi	Add the ability to collect I/O statistics on user-defined regions of a	2013-09-10 13:06:15 -07:00
video	fbdev changes for 3.12:	2013-09-05 09:49:32 -07:00
xen	Features:	2013-09-04 17:45:39 -07:00
Kbuild