linux/include
Alexei Starovoitov cff82457c5 net_sched: act_bpf: remove spinlock in fast path
Similar to act_gact/act_mirred, act_bpf can be lockless in packet processing
with extra care taken to free bpf programs after rcu grace period.
Replacement of existing act_bpf (very rare) is done with synchronize_rcu()
and final destruction is done from tc_action_ops->cleanup() callback that is
called from tcf_exts_destroy()->tcf_action_destroy()->__tcf_hash_release() when
bind and refcnt reach zero which is only possible when classifier is destroyed.
Previous two patches fixed the last two classifiers (tcindex and rsvp) to
call tcf_exts_destroy() from rcu callback.

Similar to gact/mirred there is a race between prog->filter and
prog->tcf_action. Meaning that the program being replaced may use
previous default action if it happened to return TC_ACT_UNSPEC.
act_mirred race betwen tcf_action and tcfm_dev is similar.
In all cases the race is harmless.
Long term we may want to improve the situation by replacing the whole
tc_action->priv as single pointer instead of updating inner fields one by one.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-26 11:01:45 -07:00
..
acpi Additional ACPICA material for v4.2-rc1 2015-07-02 17:11:28 -07:00
asm-generic mm: clean up per architecture MM hook header files 2015-07-17 16:39:53 -07:00
clocksource
crypto crypto: rng - Do not free default RNG when it becomes unused 2015-06-22 15:49:18 +08:00
drm Merge tag 'topic/drm-fixes-2015-08-14' of git://anongit.freedesktop.org/drm-intel into drm-next 2015-08-15 14:52:12 +10:00
dt-bindings The changes to the common clock framework for 4.2 are dominated by new 2015-07-01 19:22:00 -07:00
keys
kvm
linux NFC 4.3 pull request 2015-08-23 20:42:57 -07:00
math-emu
media Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2015-07-01 19:09:11 -07:00
memory
misc
net net_sched: act_bpf: remove spinlock in fast path 2015-08-26 11:01:45 -07:00
pcmcia
ras tracing: add trace event for memory-failure 2015-06-24 17:49:43 -07:00
rdma IB: Add rdma_cap_ib_switch helper and use where appropriate 2015-07-14 13:20:08 -04:00
rxrpc
scsi Merge branch 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2015-08-17 16:20:45 -07:00
soc Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2015-06-26 12:20:00 -07:00
sound ASoC: topology: Add Kconfig option for topology 2015-08-17 22:45:47 -07:00
target iscsi-target: Fix iscsit_start_kthreads failure OOPs 2015-07-24 14:19:43 -07:00
trace Merge branch 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2015-06-30 20:07:45 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-08-21 11:44:04 -07:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
xen
Kbuild