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author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2017-04-20 17:59:18 +0200 |
---|---|---|
committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2017-04-21 04:06:49 +0200 |
commit | dcc19d28091a86d5baf78e3fbb32e3fc3de524be (patch) | |
tree | 1b0675f001e161897b22acf17f1a10b53343a476 | |
parent | tracing/ftrace: Allow for the traceonoff probe be unique to instances (diff) | |
download | linux-dcc19d28091a86d5baf78e3fbb32e3fc3de524be.tar.xz linux-dcc19d28091a86d5baf78e3fbb32e3fc3de524be.zip |
tracing/ftrace: Allow for instances to trigger their own stacktrace probes
Have the stacktrace function trigger probe trigger stack traces within the
instance that they were added to in the set_ftrace_filter.
># cd /sys/kernel/debug/tracing
># mkdir instances/foo
># cd instances/foo
># echo schedule:stacktrace:1 > set_ftrace_filter
># cat trace
# tracer: nop
#
# entries-in-buffer/entries-written: 1/1 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
<idle>-0 [001] .N.2 202.585010: <stack trace>
=>
=> schedule
=> schedule_preempt_disabled
=> do_idle
=> cpu_startup_entry
=> start_secondary
=> verify_cpu
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-rw-r--r-- | kernel/trace/trace_functions.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 8c30ca733a5c..a3bddbfd0874 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -375,12 +375,23 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip, */ #define STACK_SKIP 4 +static __always_inline void trace_stack(struct trace_array *tr) +{ + unsigned long flags; + int pc; + + local_save_flags(flags); + pc = preempt_count(); + + __trace_stack(tr, flags, STACK_SKIP, pc); +} + static void ftrace_stacktrace(unsigned long ip, unsigned long parent_ip, struct trace_array *tr, struct ftrace_probe_ops *ops, void *data) { - trace_dump_stack(STACK_SKIP); + trace_stack(tr); } static void @@ -398,7 +409,7 @@ ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip, /* unlimited? */ if (!mapper) { - trace_dump_stack(STACK_SKIP); + trace_stack(tr); return; } @@ -417,7 +428,7 @@ ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip, new_count = old_count - 1; new_count = cmpxchg(count, old_count, new_count); if (new_count == old_count) - trace_dump_stack(STACK_SKIP); + trace_stack(tr); if (!tracing_is_on()) return; |