diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-02-22 12:03:30 +0100 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2012-04-13 11:01:52 -0500 |
| commit | e15ffe4a7a13065eb2bafa7e262b169d2b2600c2 (patch) | |
| tree | 9022fc356feefdcdcf429862e8fc1b55922708ab /include/net | |
| parent | b3b33f1273dd90754c0a1592bfe4d95f7eeaaaa9 (diff) | |
seqlock: Prevent rt starvation
If a low prio writer gets preempted while holding the seqlock write
locked, a high prio reader spins forever on RT.
To prevent this let the reader grab the spinlock, so it blocks and
eventually boosts the writer. This way the writer can proceed and
endless spinning is prevented.
For seqcount writers we disable preemption over the update code
path. Thaanks to Al Viro for distangling some VFS code to make that
possible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable-rt@vger.kernel.org
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/neighbour.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/neighbour.h b/include/net/neighbour.h index 34c996f46181..8e626fa6ccde 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -394,7 +394,7 @@ struct neighbour_cb { #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb) -static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n, +static inline void neigh_ha_snapshot(char *dst, struct neighbour *n, const struct net_device *dev) { unsigned int seq; |