Mr. Rostedt,
Just wanted to make sure there was nothing else you thought I should
modify for this patch. If there is, please let me know. I am eager to
fix anything that you think could make it better!
I hope that you had a great weekend!
Will
On Fri, Oct 13, 2017 at 2:40 PM, Will Hawkins <hawki...@borlaugic.com> wrote:
> In older versions of the kernel, event filtering by
> pid does not use the set_event_pid file. Instead,
> ftrace uses a common filter (created in make_pid_filter)
> to filter events based on PID.
>
> The syntax of the filter generated by this function is
> overly permissive. When filtering by pid, || is used
> where && should be (in certain cases) which means that
> unrelated events are captured.
>
> Signed-off-by: Will Hawkins <hawki...@borlaugic.com>
> ---
> trace-record.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/trace-record.c b/trace-record.c
> index a0b6541..741fe53 100644
> --- a/trace-record.c
> +++ b/trace-record.c
> @@ -935,14 +935,16 @@ static char *make_pid_filter(char *curr_filter, const
> char *field)
> str = filter + curr_len;
>
> for (p = filter_pids; p; p = p->next) {
> - if (p == filter_pids)
> - orit = "";
> - else
> - orit = "||";
> - if (p->exclude)
> + if (p->exclude) {
> match = "!=";
> - else
> + orit = "&&";
> + } else {
> match = "==";
> + orit = "||";
> + }
> + if (p == filter_pids)
> + orit = "";
> +
> len = sprintf(str, "%s(%s%s%d)", orit, field, match, p->pid);
> str += len;
> }
> --
> 2.7.4
>
