* [PATCH v2] trace-cmd record: Fix syntax in make_pid_filter
[not found] <CADx9qWjVny-+Sct2-pmHmZ73ohCu_6ay67-GBYP5w_gjvG0TDQ () mail ! gmail ! com>
@ 2017-10-13 18:40 ` Will Hawkins
2017-10-23 20:41 ` Will Hawkins
0 siblings, 1 reply; 3+ messages in thread
From: Will Hawkins @ 2017-10-13 18:40 UTC (permalink / raw)
To: linux-kernel, hawkinsw, rostedt; +Cc: Will Hawkins
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 <hawkinsw@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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v2] trace-cmd record: Fix syntax in make_pid_filter
2017-10-13 18:40 ` [PATCH v2] trace-cmd record: Fix syntax in make_pid_filter Will Hawkins
@ 2017-10-23 20:41 ` Will Hawkins
2017-10-31 16:17 ` Steven Rostedt
0 siblings, 1 reply; 3+ messages in thread
From: Will Hawkins @ 2017-10-23 20:41 UTC (permalink / raw)
To: linux-kernel, Will Hawkins, Steven Rostedt; +Cc: Will Hawkins
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 <hawkinsw@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 <hawkinsw@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
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v2] trace-cmd record: Fix syntax in make_pid_filter
2017-10-23 20:41 ` Will Hawkins
@ 2017-10-31 16:17 ` Steven Rostedt
0 siblings, 0 replies; 3+ messages in thread
From: Steven Rostedt @ 2017-10-31 16:17 UTC (permalink / raw)
To: Will Hawkins; +Cc: linux-kernel, Will Hawkins
On Mon, 23 Oct 2017 16:41:22 -0400
Will Hawkins <hawkinsw@borlaugic.com> wrote:
> 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 already applied this (not sure I pushed it out yet). But forgot to
tell you that I have.
Thanks!
-- Steve
^ permalink raw reply [flat|nested] 3+ messages in thread
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2017-10-13 18:40 ` [PATCH v2] trace-cmd record: Fix syntax in make_pid_filter Will Hawkins
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