From 9baf7235fb05803c64a707dbc410e0767c72a171 Mon Sep 17 00:00:00 2001 From: Anders Roxell Date: Mon, 27 May 2019 09:51:54 +0200 Subject: [PATCH] seqlock: mark raw_read_seqcount and read_seqcount_retry as __always_inline If CONFIG_FUNCTION_GRAPH_TRACER is enabled function sched_clock() in kernel/time/sched_clock.c is marked as notrace. However, functions raw_read_seqcount and read_seqcount_retry are marked as inline. If CONFIG_OPTIMIZE_INLINING is set that will make the two functions tracable which they shouldn't. Since that means that they will end up in a recursion due to the tracing code, i.e., we read the time when processing an ftrace event, and an out of line seqlock in the time handling code calls into ftrace. Rework so that functions raw_read_seqcount and read_seqcount_retry are marked with __always_inline so they will be inlined even if CONFIG_OPTIMIZE_INLINING is turned on. Signed-off-by: Anders Roxell --- include/linux/seqlock.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index bcf4cf26b8c8..1b18e3df186e 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -127,7 +127,7 @@ static inline unsigned __read_seqcount_begin(const seqcount_t *s) * seqcount without any lockdep checking and without checking or * masking the LSB. Calling code is responsible for handling that. */ -static inline unsigned raw_read_seqcount(const seqcount_t *s) +static __always_inline unsigned raw_read_seqcount(const seqcount_t *s) { unsigned ret = READ_ONCE(s->sequence); smp_rmb(); @@ -215,7 +215,8 @@ static inline int __read_seqcount_retry(const seqcount_t *s, unsigned start) * If the critical section was invalid, it must be ignored (and typically * retried). */ -static inline int read_seqcount_retry(const seqcount_t *s, unsigned start) +static +__always_inline int read_seqcount_retry(const seqcount_t *s, unsigned start) { smp_rmb(); return __read_seqcount_retry(s, start); -- 2.20.1