diff options
| author | Amos Kong <akong@redhat.com> | 2011-06-09 00:27:10 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-06-09 00:27:10 -0700 |
| commit | 61a5ff15ebdab87887861a6b128b108404e4706d (patch) | |
| tree | e439d62aa7299ad6644b37b3e569ca3de8c0f60b /tools/perf/scripts/python/failed-syscalls-by-pid.py | |
| parent | 6f7c156c08d5eaa9fff2bd062f0a2b9d09a1e7a9 (diff) | |
tun: do not put self in waitq if doing a nonblock read
Perf shows a relatively high rate (about 8%) race in
spin_lock_irqsave() when doing netperf between external host and
guest. It's mainly becuase the lock contention between the
tun_do_read() and tun_xmit_skb(), so this patch do not put self into
waitqueue to reduce this kind of race. After this patch, it drops to
4%.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/perf/scripts/python/failed-syscalls-by-pid.py')
0 files changed, 0 insertions, 0 deletions