From e57cbaf0eb006eaa207395f3bfd7ce52c1b5539c Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Thu, 3 Mar 2016 17:18:20 -0500 Subject: tracing: Do not have 'comm' filter override event 'comm' field Commit 9f61668073a8d "tracing: Allow triggers to filter for CPU ids and process names" added a 'comm' filter that will filter events based on the current tasks struct 'comm'. But this now hides the ability to filter events that have a 'comm' field too. For example, sched_migrate_task trace event. That has a 'comm' field of the task to be migrated. echo 'comm == "bash"' > events/sched_migrate_task/filter will now filter all sched_migrate_task events for tasks named "bash" that migrates other tasks (in interrupt context), instead of seeing when "bash" itself gets migrated. This fix requires a couple of changes. 1) Change the look up order for filter predicates to look at the events fields before looking at the generic filters. 2) Instead of basing the filter function off of the "comm" name, have the generic "comm" filter have its own filter_type (FILTER_COMM). Test against the type instead of the name to assign the filter function. 3) Add a new "COMM" filter that works just like "comm" but will filter based on the current task, even if the trace event contains a "comm" field. Do the same for "cpu" field, adding a FILTER_CPU and a filter "CPU". Cc: stable@vger.kernel.org # v4.3+ Fixes: 9f61668073a8d "tracing: Allow triggers to filter for CPU ids and process names" Reported-by: Matt Fleming Signed-off-by: Steven Rostedt --- include/linux/trace_events.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 429fdfc3baf5..925730bc9fc1 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -568,6 +568,8 @@ enum { FILTER_DYN_STRING, FILTER_PTR_STRING, FILTER_TRACE_FN, + FILTER_COMM, + FILTER_CPU, }; extern int trace_event_raw_init(struct trace_event_call *call); -- cgit v1.2.3