ftrace: do not process freed records

Impact: keep from converting freed records

When the tracer is started or stopped, it converts all code pointed
to by the saved records into callers to ftrace or nops. When modules
are unloaded, their records are freed, but they still exist within
the record pages.

This patch changes the code to skip over freed records.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Steven Rostedt 2008-11-14 16:21:19 -08:00 committed by Ingo Molnar
parent b17e8a37a1
commit 918c115410
1 changed files with 6 additions and 2 deletions

View File

@ -488,8 +488,12 @@ static void ftrace_replace_code(int enable)
for (i = 0; i < pg->index; i++) {
rec = &pg->records[i];
/* don't modify code that has already faulted */
if (rec->flags & FTRACE_FL_FAILED)
/*
* Skip over free records and records that have
* failed.
*/
if (rec->flags & FTRACE_FL_FREE ||
rec->flags & FTRACE_FL_FAILED)
continue;
/* ignore updates to this record's mcount site */