From dc7305606d480f34d9ed960fcaceac81d0f38436 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 12 Jan 2023 20:43:47 +0100 Subject: tracing: Remove trace_hardirqs_{on,off}_caller() Per commit 56e62a737028 ("s390: convert to generic entry") the last and only callers of trace_hardirqs_{on,off}_caller() went away, clean up. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230112195541.355283994@infradead.org --- kernel/trace/trace_preemptirq.c | 29 ----------------------------- 1 file changed, 29 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c index 1e130da1b742..629f2854e12b 100644 --- a/kernel/trace/trace_preemptirq.c +++ b/kernel/trace/trace_preemptirq.c @@ -84,35 +84,6 @@ void trace_hardirqs_off(void) } EXPORT_SYMBOL(trace_hardirqs_off); NOKPROBE_SYMBOL(trace_hardirqs_off); - -__visible void trace_hardirqs_on_caller(unsigned long caller_addr) -{ - if (this_cpu_read(tracing_irq_cpu)) { - if (!in_nmi()) - trace_irq_enable_rcuidle(CALLER_ADDR0, caller_addr); - tracer_hardirqs_on(CALLER_ADDR0, caller_addr); - this_cpu_write(tracing_irq_cpu, 0); - } - - lockdep_hardirqs_on_prepare(); - lockdep_hardirqs_on(caller_addr); -} -EXPORT_SYMBOL(trace_hardirqs_on_caller); -NOKPROBE_SYMBOL(trace_hardirqs_on_caller); - -__visible void trace_hardirqs_off_caller(unsigned long caller_addr) -{ - lockdep_hardirqs_off(caller_addr); - - if (!this_cpu_read(tracing_irq_cpu)) { - this_cpu_write(tracing_irq_cpu, 1); - tracer_hardirqs_off(CALLER_ADDR0, caller_addr); - if (!in_nmi()) - trace_irq_disable_rcuidle(CALLER_ADDR0, caller_addr); - } -} -EXPORT_SYMBOL(trace_hardirqs_off_caller); -NOKPROBE_SYMBOL(trace_hardirqs_off_caller); #endif /* CONFIG_TRACE_IRQFLAGS */ #ifdef CONFIG_TRACE_PREEMPT_TOGGLE -- cgit v1.2.3 From 408b961146be4c1a776ce285c3c289afab15298a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 12 Jan 2023 20:43:48 +0100 Subject: 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) Signed-off-by: Ingo Molnar Tested-by: Tony Lindgren Tested-by: Ulf Hansson Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Link: https://lore.kernel.org/r/20230112195541.416110581@infradead.org --- kernel/trace/trace.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/trace') 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 -- cgit v1.2.3 From 9aedeaed6fc6fe8452b9b8225e95cc2b8631ff91 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 12 Jan 2023 20:43:49 +0100 Subject: tracing, hardirq: No moar _rcuidle() tracing Robot reported that trace_hardirqs_{on,off}() tickle the forbidden _rcuidle() tracepoint through local_irq_{en,dis}able(). For 'sane' configs, these calls will only happen with RCU enabled and as such can use the regular tracepoint. This also means it's possible to trace them from NMI context again. Reported-by: kernel test robot Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230112195541.477416709@infradead.org --- kernel/trace/trace_preemptirq.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c index 629f2854e12b..f992444a0b1f 100644 --- a/kernel/trace/trace_preemptirq.c +++ b/kernel/trace/trace_preemptirq.c @@ -19,6 +19,20 @@ /* Per-cpu variable to prevent redundant calls when IRQs already off */ static DEFINE_PER_CPU(int, tracing_irq_cpu); +/* + * Use regular trace points on architectures that implement noinstr + * tooling: these calls will only happen with RCU enabled, which can + * use a regular tracepoint. + * + * On older architectures, use the rcuidle tracing methods (which + * aren't NMI-safe - so exclude NMI contexts): + */ +#ifdef CONFIG_ARCH_WANTS_NO_INSTR +#define trace(point) trace_##point +#else +#define trace(point) if (!in_nmi()) trace_##point##_rcuidle +#endif + /* * Like trace_hardirqs_on() but without the lockdep invocation. This is * used in the low level entry code where the ordering vs. RCU is important @@ -28,8 +42,7 @@ static DEFINE_PER_CPU(int, tracing_irq_cpu); void trace_hardirqs_on_prepare(void) { if (this_cpu_read(tracing_irq_cpu)) { - if (!in_nmi()) - trace_irq_enable(CALLER_ADDR0, CALLER_ADDR1); + trace(irq_enable)(CALLER_ADDR0, CALLER_ADDR1); tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1); this_cpu_write(tracing_irq_cpu, 0); } @@ -40,8 +53,7 @@ NOKPROBE_SYMBOL(trace_hardirqs_on_prepare); void trace_hardirqs_on(void) { if (this_cpu_read(tracing_irq_cpu)) { - if (!in_nmi()) - trace_irq_enable_rcuidle(CALLER_ADDR0, CALLER_ADDR1); + trace(irq_enable)(CALLER_ADDR0, CALLER_ADDR1); tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1); this_cpu_write(tracing_irq_cpu, 0); } @@ -63,8 +75,7 @@ void trace_hardirqs_off_finish(void) if (!this_cpu_read(tracing_irq_cpu)) { this_cpu_write(tracing_irq_cpu, 1); tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1); - if (!in_nmi()) - trace_irq_disable(CALLER_ADDR0, CALLER_ADDR1); + trace(irq_disable)(CALLER_ADDR0, CALLER_ADDR1); } } @@ -78,8 +89,7 @@ void trace_hardirqs_off(void) if (!this_cpu_read(tracing_irq_cpu)) { this_cpu_write(tracing_irq_cpu, 1); tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1); - if (!in_nmi()) - trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1); + trace(irq_disable)(CALLER_ADDR0, CALLER_ADDR1); } } EXPORT_SYMBOL(trace_hardirqs_off); -- cgit v1.2.3 From 3017ba4b831bc7fd67cc82e744116b6e45e259a4 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 31 Jan 2023 09:50:36 +0100 Subject: cpuidle: tracing, preempt: Squash _rcuidle tracing Extend/fix commit: 9aedeaed6fc6 ("tracing, hardirq: No moar _rcuidle() tracing") ... to also cover trace_preempt_{on,off}() which were mysteriously untouched. Fixes: 9aedeaed6fc6 ("tracing, hardirq: No moar _rcuidle() tracing") Reported-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Tested-by: Mark Rutland Link: https://lkml.kernel.org/r/Y9D5AfnOukWNOZ5q@hirez.programming.kicks-ass.net Link: https://lore.kernel.org/r/Y9jWXKgkxY5EZVwW@hirez.programming.kicks-ass.net --- kernel/trace/trace_preemptirq.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c index f992444a0b1f..e37446f7916e 100644 --- a/kernel/trace/trace_preemptirq.c +++ b/kernel/trace/trace_preemptirq.c @@ -15,10 +15,6 @@ #define CREATE_TRACE_POINTS #include -#ifdef CONFIG_TRACE_IRQFLAGS -/* Per-cpu variable to prevent redundant calls when IRQs already off */ -static DEFINE_PER_CPU(int, tracing_irq_cpu); - /* * Use regular trace points on architectures that implement noinstr * tooling: these calls will only happen with RCU enabled, which can @@ -33,6 +29,10 @@ static DEFINE_PER_CPU(int, tracing_irq_cpu); #define trace(point) if (!in_nmi()) trace_##point##_rcuidle #endif +#ifdef CONFIG_TRACE_IRQFLAGS +/* Per-cpu variable to prevent redundant calls when IRQs already off */ +static DEFINE_PER_CPU(int, tracing_irq_cpu); + /* * Like trace_hardirqs_on() but without the lockdep invocation. This is * used in the low level entry code where the ordering vs. RCU is important @@ -100,15 +100,13 @@ NOKPROBE_SYMBOL(trace_hardirqs_off); void trace_preempt_on(unsigned long a0, unsigned long a1) { - if (!in_nmi()) - trace_preempt_enable_rcuidle(a0, a1); + trace(preempt_enable)(a0, a1); tracer_preempt_on(a0, a1); } void trace_preempt_off(unsigned long a0, unsigned long a1) { - if (!in_nmi()) - trace_preempt_disable_rcuidle(a0, a1); + trace(preempt_disable)(a0, a1); tracer_preempt_off(a0, a1); } #endif -- cgit v1.2.3