[PATCH RT 18/25][RFC 3.0.23-rt39-rc1] net: u64_stat: Protect seqcount
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2012-03-06 16:21:59
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Thomas Gleixner <redacted> On RT we must prevent that the writer gets preempted inside the write section. Otherwise a preempting reader might spin forever. Signed-off-by: Thomas Gleixner <redacted> Cc: stable-rt@vger.kernel.org Signed-off-by: Steven Rostedt <rostedt@goodmis.org> --- include/linux/u64_stats_sync.h | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h
index 8da8c4e..b39549f 100644
--- a/include/linux/u64_stats_sync.h
+++ b/include/linux/u64_stats_sync.h@@ -70,6 +70,7 @@ struct u64_stats_sync { static inline void u64_stats_update_begin(struct u64_stats_sync *syncp) { #if BITS_PER_LONG==32 && defined(CONFIG_SMP) + preempt_disable_rt(); write_seqcount_begin(&syncp->seq); #endif }
@@ -78,6 +79,7 @@ static inline void u64_stats_update_end(struct u64_stats_sync *syncp) { #if BITS_PER_LONG==32 && defined(CONFIG_SMP) write_seqcount_end(&syncp->seq); + preempt_enable_rt(); #endif }
--
1.7.8.3