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| author | Namhyung Kim <namhyung@kernel.org> | 2015-04-06 14:36:16 +0900 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-04-08 09:07:09 -0300 |
| commit | 3201f0dc42f7fad9387afc4692cea3d0c730cba2 (patch) | |
| tree | 571296cc0ee74dff4bf2b8dae460c9e27d4472f8 /tools/lib | |
| parent | ba92732e9808df679ddf75c5ea1c0caae6d7dce2 (diff) | |
| download | linux-3201f0dc42f7fad9387afc4692cea3d0c730cba2.tar.bz2 | |
tools lib traceevent: Honor operator priority
Currently it ignores operator priority and just sets processed args as a
right operand. But it could result in priority inversion in case that
the right operand is also a operator arg and its priority is lower.
For example, following print format is from new kmem events.
"page=%p", REC->pfn != -1UL ? (((struct page *)(0xffffea0000000000UL)) + (REC->pfn)) : ((void *)0)
But this was treated as below:
REC->pfn != ((null - 1UL) ? ((struct page *)0xffffea0000000000UL + REC->pfn) : (void *) 0)
In this case, the right arg was '?' operator which has lower priority.
But it just sets the whole arg so making the output confusing - page was
always 0 or 1 since that's the result of logical operation.
With this patch, it can handle it properly like following:
((REC->pfn != (null - 1UL)) ? ((struct page *)0xffffea0000000000UL + REC->pfn) : (void *) 0)
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1428298576-9785-10-git-send-email-namhyung@kernel.org
[ Replaced 'swap' with 'rotate' in a comment as requested by Steve and agreed by Namhyung ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/traceevent/event-parse.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c index 6d31b6419d37..12a7e2a40c89 100644 --- a/tools/lib/traceevent/event-parse.c +++ b/tools/lib/traceevent/event-parse.c @@ -1939,7 +1939,22 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok) goto out_warn_free; type = process_arg_token(event, right, tok, type); - arg->op.right = right; + + if (right->type == PRINT_OP && + get_op_prio(arg->op.op) < get_op_prio(right->op.op)) { + struct print_arg tmp; + + /* rotate ops according to the priority */ + arg->op.right = right->op.left; + + tmp = *arg; + *arg = *right; + *right = tmp; + + arg->op.left = right; + } else { + arg->op.right = right; + } } else if (strcmp(token, "[") == 0) { |