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ftrace: fix "notrace" filtering priority

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This is a fix to give notrace filter rules priority over "set_ftrace_filter"
rules.

This fix ensures that functions which are set to be filtered and are
concurrently marked as "notrace" don't get recorded. As of now, if
a record is marked as FTRACE_FL_FILTER and is enabled, then the notrace
flag is not checked. Tested on x86-32.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Abhishek Sagar
2008-06-14 11:59:39 +05:30
committed by Ingo Molnar
parent 20764ff1ef
commit a4500b84c5
1 changed files with 9 additions and 3 deletions
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12
kernel/trace/ftrace.c
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@@ -355,20 +355,26 @@ __ftrace_replace_code(struct dyn_ftrace *rec,
* If this record is set not to trace then * If this record is set not to trace then
* do nothing. * do nothing.
* *
* If this record is set not to trace and
* it is enabled then disable it.
*
* If this record is not set to be filtered and * If this record is not set to be filtered and
* it is enabled, disable it. * it is enabled, disable it.
*/ */
fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE |
FTRACE_FL_ENABLED);
if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) || if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) ||
(fl == 0) || (rec->flags & FTRACE_FL_NOTRACE)) (fl == (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE)) ||
!fl || (fl == FTRACE_FL_NOTRACE))
return 0; return 0;
/* /*
* If it is enabled disable it, * If it is enabled disable it,
* otherwise enable it! * otherwise enable it!
*/ */
if (fl == FTRACE_FL_ENABLED) { if (fl & FTRACE_FL_ENABLED) {
/* swap new and old */ /* swap new and old */
new = old; new = old;
old = ftrace_call_replace(ip, FTRACE_ADDR); old = ftrace_call_replace(ip, FTRACE_ADDR);