From: "Steven Rostedt (Red Hat)" <[email protected]> Commit fcc742eaad7c "ring-buffer: Add event descriptor to simplify passing data" added a descriptor that holds various data instead of passing around several variables through parameters. The problem was that one of the parameters was modified in a function and the code was designed not to have an effect on that modified parameter. Now that the parameter is a descriptor and any modifications to it are non-volatile, the size of the data could be unnecessarily expanded.
Remove the extra space added if a timestamp was added and the event went across the page. Cc: [email protected] # 4.3+ Fixes: fcc742eaad7c "ring-buffer: Add event descriptor to simplify passing data" Signed-off-by: Steven Rostedt <[email protected]> --- kernel/trace/ring_buffer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 4dd6d5bc4e11..9c6045a27ba3 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2797,8 +2797,11 @@ rb_reserve_next_event(struct ring_buffer *buffer, event = __rb_reserve_next(cpu_buffer, &info); - if (unlikely(PTR_ERR(event) == -EAGAIN)) + if (unlikely(PTR_ERR(event) == -EAGAIN)) { + if (info.add_timestamp) + info.length -= RB_LEN_TIME_EXTEND; goto again; + } if (!event) goto out_fail; -- 2.6.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
