linux/include
Eric Dumazet fc66f95c68 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>
2010-10-11 13:06:53 -07:00
..
acpi ACPI: Fix typos 2010-09-28 21:38:19 -04:00
asm-generic gpio: doc updates 2010-09-09 18:57:24 -07:00
crypto
drm drm: Hold the mutex when dropping the last GEM reference (v2) 2010-10-01 21:08:45 +10:00
keys
linux neigh: speedup neigh_hh_init() 2010-10-11 09:16:57 -07:00
math-emu
media
mtd
net net dst: use a percpu_counter to track entries 2010-10-11 13:06:53 -07:00
pcmcia
rdma
rxrpc
scsi
sound ALSA: emu10k1 - delay the PCM interrupts (add pcm_irq_delay parameter) 2010-08-18 15:10:59 +02:00
trace Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-24 12:21:49 -07:00
video include: replace unifdef-y with header-y 2010-08-14 22:26:51 +02:00
xen xen: pvhvm: make it clearer that XEN_UNPLUG_* define bits in a bitfield 2010-08-23 12:01:35 +01:00
Kbuild