From ce33c845b030c9cf768370c951bc699470b09fa7 Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Sun, 20 Feb 2022 23:49:57 +0100 Subject: tracing: Dump stacktrace trigger to the corresponding instance The stacktrace event trigger is not dumping the stacktrace to the instance where it was enabled, but to the global "instance." Use the private_data, pointing to the trigger file, to figure out the corresponding trace instance, and use it in the trigger action, like snapshot_trigger does. Link: https://lkml.kernel.org/r/afbb0b4f18ba92c276865bc97204d438473f4ebc.1645396236.git.bristot@kernel.org Cc: stable@vger.kernel.org Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables") Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_trigger.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'kernel/trace/trace_events_trigger.c') diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index d00fee705f9c..e0d50c9577f3 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1540,7 +1540,12 @@ stacktrace_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event) { - trace_dump_stack(STACK_SKIP); + struct trace_event_file *file = data->private_data; + + if (file) + __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP); + else + trace_dump_stack(STACK_SKIP); } static void -- cgit v1.2.3 From 302e9edd54985f584cfc180098f3554774126969 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Wed, 23 Feb 2022 22:38:37 -0500 Subject: tracing: Have traceon and traceoff trigger honor the instance If a trigger is set on an event to disable or enable tracing within an instance, then tracing should be disabled or enabled in the instance and not at the top level, which is confusing to users. Link: https://lkml.kernel.org/r/20220223223837.14f94ec3@rorschach.local.home Cc: stable@vger.kernel.org Fixes: ae63b31e4d0e2 ("tracing: Separate out trace events from global variables") Tested-by: Daniel Bristot de Oliveira Reviewed-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_trigger.c | 52 ++++++++++++++++++++++++++++++++----- 1 file changed, 46 insertions(+), 6 deletions(-) (limited to 'kernel/trace/trace_events_trigger.c') diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index e0d50c9577f3..efe563140f27 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1295,6 +1295,16 @@ traceon_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event) { + struct trace_event_file *file = data->private_data; + + if (file) { + if (tracer_tracing_is_on(file->tr)) + return; + + tracer_tracing_on(file->tr); + return; + } + if (tracing_is_on()) return; @@ -1306,8 +1316,15 @@ traceon_count_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event) { - if (tracing_is_on()) - return; + struct trace_event_file *file = data->private_data; + + if (file) { + if (tracer_tracing_is_on(file->tr)) + return; + } else { + if (tracing_is_on()) + return; + } if (!data->count) return; @@ -1315,7 +1332,10 @@ traceon_count_trigger(struct event_trigger_data *data, if (data->count != -1) (data->count)--; - tracing_on(); + if (file) + tracer_tracing_on(file->tr); + else + tracing_on(); } static void @@ -1323,6 +1343,16 @@ traceoff_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event) { + struct trace_event_file *file = data->private_data; + + if (file) { + if (!tracer_tracing_is_on(file->tr)) + return; + + tracer_tracing_off(file->tr); + return; + } + if (!tracing_is_on()) return; @@ -1334,8 +1364,15 @@ traceoff_count_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event) { - if (!tracing_is_on()) - return; + struct trace_event_file *file = data->private_data; + + if (file) { + if (!tracer_tracing_is_on(file->tr)) + return; + } else { + if (!tracing_is_on()) + return; + } if (!data->count) return; @@ -1343,7 +1380,10 @@ traceoff_count_trigger(struct event_trigger_data *data, if (data->count != -1) (data->count)--; - tracing_off(); + if (file) + tracer_tracing_off(file->tr); + else + tracing_off(); } static int -- cgit v1.2.3 From bc82c38a6933aab308387d4aca47e0a05de7b553 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 11 Feb 2022 08:10:18 +0100 Subject: tracing: Uninline trace_trigger_soft_disabled() partly On a powerpc32 build with CONFIG_CC_OPTIMISE_FOR_SIZE, the inline keyword is not honored and trace_trigger_soft_disabled() appears approx 50 times in vmlinux. Adding -Winline to the build, the following message appears: ./include/linux/trace_events.h:712:1: error: inlining failed in call to 'trace_trigger_soft_disabled': call is unlikely and code size would grow [-Werror=inline] That function is rather big for an inlined function: c003df60 : c003df60: 94 21 ff f0 stwu r1,-16(r1) c003df64: 7c 08 02 a6 mflr r0 c003df68: 90 01 00 14 stw r0,20(r1) c003df6c: bf c1 00 08 stmw r30,8(r1) c003df70: 83 e3 00 24 lwz r31,36(r3) c003df74: 73 e9 01 00 andi. r9,r31,256 c003df78: 41 82 00 10 beq c003df88 c003df7c: 38 60 00 00 li r3,0 c003df80: 39 61 00 10 addi r11,r1,16 c003df84: 4b fd 60 ac b c0014030 <_rest32gpr_30_x> c003df88: 73 e9 00 80 andi. r9,r31,128 c003df8c: 7c 7e 1b 78 mr r30,r3 c003df90: 41 a2 00 14 beq c003dfa4 c003df94: 38 c0 00 00 li r6,0 c003df98: 38 a0 00 00 li r5,0 c003df9c: 38 80 00 00 li r4,0 c003dfa0: 48 05 c5 f1 bl c009a590 c003dfa4: 73 e9 00 40 andi. r9,r31,64 c003dfa8: 40 82 00 28 bne c003dfd0 c003dfac: 73 ff 02 00 andi. r31,r31,512 c003dfb0: 41 82 ff cc beq c003df7c c003dfb4: 80 01 00 14 lwz r0,20(r1) c003dfb8: 83 e1 00 0c lwz r31,12(r1) c003dfbc: 7f c3 f3 78 mr r3,r30 c003dfc0: 83 c1 00 08 lwz r30,8(r1) c003dfc4: 7c 08 03 a6 mtlr r0 c003dfc8: 38 21 00 10 addi r1,r1,16 c003dfcc: 48 05 6f 6c b c0094f38 c003dfd0: 38 60 00 01 li r3,1 c003dfd4: 4b ff ff ac b c003df80 However it is located in a hot path so inlining it is important. But forcing inlining of the entire function by using __always_inline leads to increasing the text size by approx 20 kbytes. Instead, split the fonction in two parts, one part with the likely fast path, flagged __always_inline, and a second part out of line. With this change, on a powerpc32 with CONFIG_CC_OPTIMISE_FOR_SIZE vmlinux text increases by only 1,4 kbytes, which is partly compensated by a decrease of vmlinux data by 7 kbytes. On ppc64_defconfig which has CONFIG_CC_OPTIMISE_FOR_SPEED, this change reduces vmlinux text by more than 30 kbytes. Link: https://lkml.kernel.org/r/69ce0986a52d026d381d612801d978aa4f977460.1644563295.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy Signed-off-by: Steven Rostedt (Google) --- include/linux/trace_events.h | 22 ++++++++++++---------- kernel/trace/trace_events_trigger.c | 14 ++++++++++++++ 2 files changed, 26 insertions(+), 10 deletions(-) (limited to 'kernel/trace/trace_events_trigger.c') diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 70c069aef02c..dcea51fb60e2 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -699,6 +699,8 @@ event_triggers_post_call(struct trace_event_file *file, bool trace_event_ignore_this_pid(struct trace_event_file *trace_file); +bool __trace_trigger_soft_disabled(struct trace_event_file *file); + /** * trace_trigger_soft_disabled - do triggers and test if soft disabled * @file: The file pointer of the event to test @@ -708,20 +710,20 @@ bool trace_event_ignore_this_pid(struct trace_event_file *trace_file); * triggers that require testing the fields, it will return true, * otherwise false. */ -static inline bool +static __always_inline bool trace_trigger_soft_disabled(struct trace_event_file *file) { unsigned long eflags = file->flags; - if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) { - if (eflags & EVENT_FILE_FL_TRIGGER_MODE) - event_triggers_call(file, NULL, NULL, NULL); - if (eflags & EVENT_FILE_FL_SOFT_DISABLED) - return true; - if (eflags & EVENT_FILE_FL_PID_FILTER) - return trace_event_ignore_this_pid(file); - } - return false; + if (likely(!(eflags & (EVENT_FILE_FL_TRIGGER_MODE | + EVENT_FILE_FL_SOFT_DISABLED | + EVENT_FILE_FL_PID_FILTER)))) + return false; + + if (likely(eflags & EVENT_FILE_FL_TRIGGER_COND)) + return false; + + return __trace_trigger_soft_disabled(file); } #ifdef CONFIG_BPF_EVENTS diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index efe563140f27..7eb9d04f1c2e 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -84,6 +84,20 @@ event_triggers_call(struct trace_event_file *file, } EXPORT_SYMBOL_GPL(event_triggers_call); +bool __trace_trigger_soft_disabled(struct trace_event_file *file) +{ + unsigned long eflags = file->flags; + + if (eflags & EVENT_FILE_FL_TRIGGER_MODE) + event_triggers_call(file, NULL, NULL, NULL); + if (eflags & EVENT_FILE_FL_SOFT_DISABLED) + return true; + if (eflags & EVENT_FILE_FL_PID_FILTER) + return trace_event_ignore_this_pid(file); + return false; +} +EXPORT_SYMBOL_GPL(__trace_trigger_soft_disabled); + /** * event_triggers_post_call - Call 'post_triggers' for a trace event * @file: The trace_event_file associated with the event -- cgit v1.2.3