[PATCH v2 06/16] u64_stats: Mark the update helpers used by BPF notrace
flat view
WARM1d
From: Song Liu <song@kernel.org>
Date: 2026-10-23 01:11:28
Also in:
live-patching, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
bpf_prog_inc_misses_counter() is notrace because it runs when a BPF program was not run due to recursion. If it could call traced code, an fentry program attached to that code would recurse forever. It calls u64_stats_update_begin_irqsave(), u64_stats_inc() and u64_stats_update_end_irqrestore(). The BPF trampoline calls u64_stats_add() and u64_stats_inc() from __update_prog_stats() in the same way. These are plain inline helpers, so an out-of-line copy is untraced only because inline implies notrace. Mark these helpers, and the __u64_stats_*() helpers they call, notrace explicitly. No functional change. Assisted-by: Claude:claude-opus-5 Signed-off-by: Song Liu <song@kernel.org> --- include/linux/u64_stats_sync.h | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h
index f47cf4d78ad7..06e5bffd0287 100644
--- a/include/linux/u64_stats_sync.h
+++ b/include/linux/u64_stats_sync.h@@ -92,7 +92,7 @@ static inline void u64_stats_set(u64_stats_t *p, u64 val) local64_set(&p->v, val); } -static inline void u64_stats_add(u64_stats_t *p, unsigned long val) +static inline void notrace u64_stats_add(u64_stats_t *p, unsigned long val) { local64_add(val, &p->v); }
@@ -102,16 +102,16 @@ static inline void u64_stats_sub(u64_stats_t *p, s64 val) local64_sub(val, &p->v); } -static inline void u64_stats_inc(u64_stats_t *p) +static inline void notrace u64_stats_inc(u64_stats_t *p) { local64_inc(&p->v); } static inline void u64_stats_init(struct u64_stats_sync *syncp) { } -static inline void __u64_stats_update_begin(struct u64_stats_sync *syncp) { } -static inline void __u64_stats_update_end(struct u64_stats_sync *syncp) { } -static inline unsigned long __u64_stats_irqsave(void) { return 0; } -static inline void __u64_stats_irqrestore(unsigned long flags) { } +static inline void notrace __u64_stats_update_begin(struct u64_stats_sync *syncp) { } +static inline void notrace __u64_stats_update_end(struct u64_stats_sync *syncp) { } +static inline unsigned long notrace __u64_stats_irqsave(void) { return 0; } +static inline void notrace __u64_stats_irqrestore(unsigned long flags) { } static inline unsigned int __u64_stats_fetch_begin(const struct u64_stats_sync *syncp) { return 0;
@@ -145,7 +145,7 @@ static inline void u64_stats_set(u64_stats_t *p, u64 val) p->v = val; } -static inline void u64_stats_add(u64_stats_t *p, unsigned long val) +static inline void notrace u64_stats_add(u64_stats_t *p, unsigned long val) { p->v += val; }
@@ -155,7 +155,7 @@ static inline void u64_stats_sub(u64_stats_t *p, s64 val) p->v -= val; } -static inline void u64_stats_inc(u64_stats_t *p) +static inline void notrace u64_stats_inc(u64_stats_t *p) { p->v++; }
@@ -166,19 +166,19 @@ static inline void u64_stats_inc(u64_stats_t *p) seqcount_init(&__s->seq); \ } while (0) -static inline void __u64_stats_update_begin(struct u64_stats_sync *syncp) +static inline void notrace __u64_stats_update_begin(struct u64_stats_sync *syncp) { preempt_disable_nested(); write_seqcount_begin(&syncp->seq); } -static inline void __u64_stats_update_end(struct u64_stats_sync *syncp) +static inline void notrace __u64_stats_update_end(struct u64_stats_sync *syncp) { write_seqcount_end(&syncp->seq); preempt_enable_nested(); } -static inline unsigned long __u64_stats_irqsave(void) +static inline unsigned long notrace __u64_stats_irqsave(void) { unsigned long flags;
@@ -186,7 +186,7 @@ static inline unsigned long __u64_stats_irqsave(void) return flags; } -static inline void __u64_stats_irqrestore(unsigned long flags) +static inline void notrace __u64_stats_irqrestore(unsigned long flags) { local_irq_restore(flags); }
@@ -213,7 +213,7 @@ static inline void u64_stats_update_end(struct u64_stats_sync *syncp) __u64_stats_update_end(syncp); } -static inline unsigned long u64_stats_update_begin_irqsave(struct u64_stats_sync *syncp) +static inline unsigned long notrace u64_stats_update_begin_irqsave(struct u64_stats_sync *syncp) { unsigned long flags = __u64_stats_irqsave();
@@ -221,8 +221,8 @@ static inline unsigned long u64_stats_update_begin_irqsave(struct u64_stats_sync return flags; } -static inline void u64_stats_update_end_irqrestore(struct u64_stats_sync *syncp, - unsigned long flags) +static inline void notrace u64_stats_update_end_irqrestore(struct u64_stats_sync *syncp, + unsigned long flags) { __u64_stats_update_end(syncp); __u64_stats_irqrestore(flags);
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2.53.0-Meta