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author | Eric Dumazet | 2016-04-01 17:52:12 +0200 |
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committer | David S. Miller | 2016-04-05 04:11:19 +0200 |
commit | a4298e4522d687a79af8f8fbb7eca68399ab2d81 (patch) | |
tree | d7a2c3d16b4659a7121b993f4ba690f20adc99fd /include/linux/udp.h | |
parent | Merge branch '10GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirshe... (diff) | |
download | kernel-qcow2-linux-a4298e4522d687a79af8f8fbb7eca68399ab2d81.tar.gz kernel-qcow2-linux-a4298e4522d687a79af8f8fbb7eca68399ab2d81.tar.xz kernel-qcow2-linux-a4298e4522d687a79af8f8fbb7eca68399ab2d81.zip |
net: add SOCK_RCU_FREE socket flag
We want a generic way to insert an RCU grace period before socket
freeing for cases where RCU_SLAB_DESTROY_BY_RCU is adding too
much overhead.
SLAB_DESTROY_BY_RCU strict rules force us to take a reference
on the socket sk_refcnt, and it is a performance problem for UDP
encapsulation, or TCP synflood behavior, as many CPUs might
attempt the atomic operations on a shared sk_refcnt
UDP sockets and TCP listeners can set SOCK_RCU_FREE so that their
lookup can use traditional RCU rules, without refcount changes.
They can set the flag only once hashed and visible by other cpus.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Tested-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/udp.h')
0 files changed, 0 insertions, 0 deletions