diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2023-01-12 22:43:48 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-01-13 13:48:16 +0300 |
| commit | 408b961146be4c1a776ce285c3c289afab15298a (patch) | |
| tree | 0640bf27ac8c20c5b50c2e75474d1337e3732df3 | |
| parent | dc7305606d480f34d9ed960fcaceac81d0f38436 (diff) | |
| download | linux-408b961146be4c1a776ce285c3c289afab15298a.tar.xz | |
tracing: WARN on rcuidle
ARCH_WANTS_NO_INSTR (a superset of CONFIG_GENERIC_ENTRY) disallows any
and all tracing when RCU isn't enabled.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195541.416110581@infradead.org
| -rw-r--r-- | include/linux/tracepoint.h | 15 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 3 |
2 files changed, 16 insertions, 2 deletions
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 4b33b95eb8be..552f80b8362f 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -178,6 +178,17 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) #endif /* CONFIG_HAVE_STATIC_CALL */ /* + * ARCH_WANTS_NO_INSTR archs are expected to have sanitized entry and idle + * code that disallow any/all tracing/instrumentation when RCU isn't watching. + */ +#ifdef CONFIG_ARCH_WANTS_NO_INSTR +#define RCUIDLE_COND(rcuidle) (rcuidle) +#else +/* srcu can't be used from NMI */ +#define RCUIDLE_COND(rcuidle) (rcuidle && in_nmi()) +#endif + +/* * it_func[0] is never NULL because there is at least one element in the array * when the array itself is non NULL. */ @@ -188,8 +199,8 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) if (!(cond)) \ return; \ \ - /* srcu can't be used from NMI */ \ - WARN_ON_ONCE(rcuidle && in_nmi()); \ + if (WARN_ON_ONCE(RCUIDLE_COND(rcuidle))) \ + return; \ \ /* keep srcu and sched-rcu usage consistent */ \ preempt_disable_notrace(); \ diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a555a861b978..54ec1592ac79 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3128,6 +3128,9 @@ void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, return; } + if (WARN_ON_ONCE(IS_ENABLED(CONFIG_GENERIC_ENTRY))) + return; + /* * When an NMI triggers, RCU is enabled via ct_nmi_enter(), * but if the above rcu_is_watching() failed, then the NMI |