The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Thanks, Sasha
------------------ original commit in Linus's tree ------------------
From 6c34df6f350df9579ce99d887a2b5fa14cc13b32 Mon Sep 17 00:00:00 2001
From: Pingfan Liu kernelfans@gmail.com Date: Sat, 14 Aug 2021 11:45:38 +0800 Subject: [PATCH] tracing: Apply trace filters on all output channels
The event filters are not applied on all of the output, which results in the flood of printk when using tp_printk. Unfolding event_trigger_unlock_commit_regs() into trace_event_buffer_commit(), so the filters can be applied on every output.
Link: https://lkml.kernel.org/r/20210814034538.8428-1-kernelfans@gmail.com
Cc: stable@vger.kernel.org Fixes: 0daa2302968c1 ("tracing: Add tp_printk cmdline to have tracepoints go to printk()") Signed-off-by: Pingfan Liu kernelfans@gmail.com Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org --- kernel/trace/trace.c | 18 +++++++++++++++--- kernel/trace/trace.h | 32 -------------------------------- 2 files changed, 15 insertions(+), 35 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 33899a71fdc1..a1adb29ef5c1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2897,14 +2897,26 @@ int tracepoint_printk_sysctl(struct ctl_table *table, int write,
void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) { + enum event_trigger_type tt = ETT_NONE; + struct trace_event_file *file = fbuffer->trace_file; + + if (__event_trigger_test_discard(file, fbuffer->buffer, fbuffer->event, + fbuffer->entry, &tt)) + goto discard; + if (static_key_false(&tracepoint_printk_key.key)) output_printk(fbuffer);
if (static_branch_unlikely(&trace_event_exports_enabled)) ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT); - event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer, - fbuffer->event, fbuffer->entry, - fbuffer->trace_ctx, fbuffer->regs); + + trace_buffer_unlock_commit_regs(file->tr, fbuffer->buffer, + fbuffer->event, fbuffer->trace_ctx, fbuffer->regs); + +discard: + if (tt) + event_triggers_post_call(file, tt); + } EXPORT_SYMBOL_GPL(trace_event_buffer_commit);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index a180abf76d4e..4a0e693000c6 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1389,38 +1389,6 @@ event_trigger_unlock_commit(struct trace_event_file *file, event_triggers_post_call(file, tt); }
-/** - * event_trigger_unlock_commit_regs - handle triggers and finish event commit - * @file: The file pointer associated with the event - * @buffer: The ring buffer that the event is being written to - * @event: The event meta data in the ring buffer - * @entry: The event itself - * @trace_ctx: The tracing context flags. - * - * This is a helper function to handle triggers that require data - * from the event itself. It also tests the event against filters and - * if the event is soft disabled and should be discarded. - * - * Same as event_trigger_unlock_commit() but calls - * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). - */ -static inline void -event_trigger_unlock_commit_regs(struct trace_event_file *file, - struct trace_buffer *buffer, - struct ring_buffer_event *event, - void *entry, unsigned int trace_ctx, - struct pt_regs *regs) -{ - enum event_trigger_type tt = ETT_NONE; - - if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) - trace_buffer_unlock_commit_regs(file->tr, buffer, event, - trace_ctx, regs); - - if (tt) - event_triggers_post_call(file, tt); -} - #define FILTER_PRED_INVALID ((unsigned short)-1) #define FILTER_PRED_IS_RIGHT (1 << 15) #define FILTER_PRED_FOLD (1 << 15)