diff options
| author | Namhyung Kim <namhyung@kernel.org> | 2014-06-11 17:06:54 +0900 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-07-01 07:13:41 -0400 |
| commit | ef2fbe16ac176c21e3b3013c169e6fdb71ec56c7 (patch) | |
| tree | 8344a51e21bb16d6823a94c769290bfc6645385e /kernel | |
| parent | 1f61be007e16a5d60b1cf868aa30d87f181e8e14 (diff) | |
| download | op-kernel-dev-ef2fbe16ac176c21e3b3013c169e6fdb71ec56c7.zip op-kernel-dev-ef2fbe16ac176c21e3b3013c169e6fdb71ec56c7.tar.gz | |
ftrace: Do not copy hash if O_TRUNC is set
When a filter file is open for writing and O_TRUNC is set, there's no
need to copy and free the filter entries.
Link: http://lkml.kernel.org/p/1402474014-28655-2-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/ftrace.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e14ff4c..232b898 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3010,7 +3010,13 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, hash = ops->filter_hash; if (file->f_mode & FMODE_WRITE) { - iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); + const int size_bits = FTRACE_HASH_DEFAULT_BITS; + + if (file->f_flags & O_TRUNC) + iter->hash = alloc_ftrace_hash(size_bits); + else + iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); + if (!iter->hash) { trace_parser_put(&iter->parser); kfree(iter); @@ -3019,10 +3025,6 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, } } - if ((file->f_mode & FMODE_WRITE) && - (file->f_flags & O_TRUNC)) - ftrace_filter_reset(iter->hash); - if (file->f_mode & FMODE_READ) { iter->pg = ftrace_pages_start; |
