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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2010-10-08 06:37:34 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-10-11 13:06:53 -0700 |
| commit | fc66f95c68b6d4535a0ea2ea15d5cf626e310956 (patch) | |
| tree | ac3a7f08ad741a67ff683bf93e5669ddcae95ed7 /net/ipv4/xfrm4_policy.c | |
| parent | 0ed8ddf4045fcfcac36bad753dc4046118c603ec (diff) | |
| download | linux-fc66f95c68b6d4535a0ea2ea15d5cf626e310956.tar.bz2 | |
net dst: use a percpu_counter to track entries
struct dst_ops tracks number of allocated dst in an atomic_t field,
subject to high cache line contention in stress workload.
Switch to a percpu_counter, to reduce number of time we need to dirty a
central location. Place it on a separate cache line to avoid dirtying
read only fields.
Stress test :
(Sending 160.000.000 UDP frames,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_TRIE, SLUB/NUMA)
Before:
real 0m51.179s
user 0m15.329s
sys 10m15.942s
After:
real 0m45.570s
user 0m15.525s
sys 9m56.669s
With a small reordering of struct neighbour fields, subject of a
following patch, (to separate refcnt from other read mostly fields)
real 0m41.841s
user 0m15.261s
sys 8m45.949s
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/xfrm4_policy.c')
| -rw-r--r-- | net/ipv4/xfrm4_policy.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index a580349f0b8a..4464f3bff6a7 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -174,7 +174,7 @@ static inline int xfrm4_garbage_collect(struct dst_ops *ops) struct net *net = container_of(ops, struct net, xfrm.xfrm4_dst_ops); xfrm4_policy_afinfo.garbage_collect(net); - return (atomic_read(&ops->entries) > ops->gc_thresh * 2); + return (dst_entries_get_slow(ops) > ops->gc_thresh * 2); } static void xfrm4_update_pmtu(struct dst_entry *dst, u32 mtu) @@ -232,7 +232,6 @@ static struct dst_ops xfrm4_dst_ops = { .ifdown = xfrm4_dst_ifdown, .local_out = __ip_local_out, .gc_thresh = 1024, - .entries = ATOMIC_INIT(0), }; static struct xfrm_policy_afinfo xfrm4_policy_afinfo = { @@ -288,6 +287,7 @@ void __init xfrm4_init(int rt_max_size) * and start cleaning when were 1/2 full */ xfrm4_dst_ops.gc_thresh = rt_max_size/2; + dst_entries_init(&xfrm4_dst_ops); xfrm4_state_init(); xfrm4_policy_init(); |