diff options
| author |   Jakob Koschel <jakobkoschel@gmail.com> | 2022-04-27 19:07:31 +0200 |
|---|---|---|
| committer |   Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-04-27 17:19:30 -0400 |
| commit | 1da27a25054f7660f7bb27ad4ccf036ee6ba51e9 (patch) | |
| tree | 4a6558827f209b645cbcc68cf79cb3155b80390f | |
| parent | tracing: Add documentation for trace clock tai (diff) | |
| download | linux-dev-1da27a25054f7660f7bb27ad4ccf036ee6ba51e9.tar.xz linux-dev-1da27a25054f7660f7bb27ad4ccf036ee6ba51e9.zip | |
tracing: Remove usage of list iterator after the loop body
In preparation to limit the scope of the list iterator variable to the
traversal loop, use a dedicated pointer to point to the found element
[1].
Before, the code implicitly used the head when no element was found
when using &pos->list. Since the new variable is only set if an
element was found, the head needs to be used explicitly if the
variable is NULL.
Link: https://lkml.kernel.org/r/20220427170734.819891-2-jakobkoschel@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/trace_output.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index d89e3f7e26eb..67f47ea27921 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -692,7 +692,7 @@ static LIST_HEAD(ftrace_event_list); static int trace_search_list(struct list_head **list) { - struct trace_event *e; + struct trace_event *e = NULL, *iter; int next = __TRACE_LAST_TYPE; if (list_empty(&ftrace_event_list)) { @@ -704,9 +704,11 @@ static int trace_search_list(struct list_head **list) * We used up all possible max events, * lets see if somebody freed one. */ - list_for_each_entry(e, &ftrace_event_list, list) { - if (e->type != next) + list_for_each_entry(iter, &ftrace_event_list, list) { + if (iter->type != next) { + e = iter; break; + } next++; } @@ -714,7 +716,10 @@ static int trace_search_list(struct list_head **list) if (next > TRACE_EVENT_TYPE_MAX) return 0; - *list = &e->list; + if (e) + *list = &e->list; + else + *list = &ftrace_event_list; return next; } |