Introduce light versions of u64_stats helpers for context where
either preempt or IRQs are disabled. This way we can make this library
usable by scheduler irqtime accounting which currenty implement its
ad-hoc version.
Cc: Rik van Riel <r...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: Wanpeng Li <wanpeng...@hotmail.com>
Cc: Mike Galbraith <efa...@gmx.de>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Eric Dumazet <eric.duma...@gmail.com>
Signed-off-by: Frederic Weisbecker <fweis...@gmail.com>
---
include/linux/u64_stats_sync.h | 51 ++++++++++++++++++++++--------------------
1 file changed, 27 insertions(+), 24 deletions(-)
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h
index d3a2bb7..650f3dd 100644
--- a/include/linux/u64_stats_sync.h
+++ b/include/linux/u64_stats_sync.h
@@ -103,29 +103,40 @@ static inline void u64_stats_update_end_raw(struct
u64_stats_sync *syncp)
#endif
}
+static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync
*syncp)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+ return read_seqcount_begin(&syncp->seq);
+#else
+ return 0;
+#endif
+}
+
static inline unsigned int u64_stats_fetch_begin(const struct u64_stats_sync
*syncp)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
- return read_seqcount_begin(&syncp->seq);
-#else
-#if BITS_PER_LONG==32
+#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
preempt_disable();
#endif
- return 0;
+ return __u64_stats_fetch_begin(syncp);
+}
+
+static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
+ unsigned int start)
+{
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
+ return read_seqcount_retry(&syncp->seq, start);
+#else
+ return false;
#endif
}
static inline bool u64_stats_fetch_retry(const struct u64_stats_sync *syncp,
unsigned int start)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
- return read_seqcount_retry(&syncp->seq, start);
-#else
-#if BITS_PER_LONG==32
+#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
preempt_enable();
#endif
- return false;
-#endif
+ return __u64_stats_fetch_retry(syncp, start);
}
/*
@@ -136,27 +147,19 @@ static inline bool u64_stats_fetch_retry(const struct
u64_stats_sync *syncp,
*/
static inline unsigned int u64_stats_fetch_begin_irq(const struct
u64_stats_sync *syncp)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
- return read_seqcount_begin(&syncp->seq);
-#else
-#if BITS_PER_LONG==32
+#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
local_irq_disable();
#endif
- return 0;
-#endif
+ return __u64_stats_fetch_begin(syncp);
}
static inline bool u64_stats_fetch_retry_irq(const struct u64_stats_sync
*syncp,
- unsigned int start)
+ unsigned int start)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
- return read_seqcount_retry(&syncp->seq, start);
-#else
-#if BITS_PER_LONG==32
+#if BITS_PER_LONG==32 && !defined(CONFIG_SMP)
local_irq_enable();
#endif
- return false;
-#endif
+ return __u64_stats_fetch_retry(syncp, start);
}
#endif /* _LINUX_U64_STATS_SYNC_H */
--
2.7.4
