* [patch] trace: find the correct ftrace event
@ 2010-03-20 13:19 Dan Carpenter
2010-03-20 13:37 ` Steven Rostedt
0 siblings, 1 reply; 8+ messages in thread
From: Dan Carpenter @ 2010-03-20 13:19 UTC (permalink / raw)
To: Ingo Molnar
Cc: Frederic Weisbecker, Steven Rostedt, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
The original code doesn't work because "call" is never NULL there.
Signed-off-by: Dan Carpenter <error27@gmail.com>
---
My code should work, but it seems like there should but it seems like
there should be a more elegant way to do this?
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 4615f62..6070c70 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
struct event_filter *filter;
struct filter_parse_state *ps;
struct ftrace_event_call *call = NULL;
+ int found = 0;
mutex_lock(&event_mutex);
list_for_each_entry(call, &ftrace_events, list) {
- if (call->id == event_id)
+ if (call->id == event_id) {
+ found = 1;
break;
+ }
}
err = -EINVAL;
- if (!call)
+ if (!found)
goto out_unlock;
err = -EEXIST;
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [patch] trace: find the correct ftrace event
2010-03-20 13:19 [patch] trace: find the correct ftrace event Dan Carpenter
@ 2010-03-20 13:37 ` Steven Rostedt
2010-03-20 13:56 ` Dan Carpenter
0 siblings, 1 reply; 8+ messages in thread
From: Steven Rostedt @ 2010-03-20 13:37 UTC (permalink / raw)
To: Dan Carpenter
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
On Sat, 2010-03-20 at 16:19 +0300, Dan Carpenter wrote:
> The original code doesn't work because "call" is never NULL there.
A one line change would have done the same ;-)
> Signed-off-by: Dan Carpenter <error27@gmail.com>
> ---
> My code should work, but it seems like there should but it seems like
> there should be a more elegant way to do this?
>
> diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> index 4615f62..6070c70 100644
> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
> struct event_filter *filter;
> struct filter_parse_state *ps;
> struct ftrace_event_call *call = NULL;
> + int found = 0;
>
> mutex_lock(&event_mutex);
>
> list_for_each_entry(call, &ftrace_events, list) {
> - if (call->id == event_id)
> + if (call->id == event_id) {
> + found = 1;
> break;
> + }
> }
>
> err = -EINVAL;
> - if (!call)
if (call == &ftrace_events)
-- Steve
> + if (!found)
> goto out_unlock;
>
> err = -EEXIST;
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [patch] trace: find the correct ftrace event
2010-03-20 13:37 ` Steven Rostedt
@ 2010-03-20 13:56 ` Dan Carpenter
2010-03-20 14:07 ` Steven Rostedt
0 siblings, 1 reply; 8+ messages in thread
From: Dan Carpenter @ 2010-03-20 13:56 UTC (permalink / raw)
To: Steven Rostedt
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
On Sat, Mar 20, 2010 at 09:37:13AM -0400, Steven Rostedt wrote:
> On Sat, 2010-03-20 at 16:19 +0300, Dan Carpenter wrote:
> > The original code doesn't work because "call" is never NULL there.
>
> A one line change would have done the same ;-)
>
> > Signed-off-by: Dan Carpenter <error27@gmail.com>
> > ---
> > My code should work, but it seems like there should but it seems like
> > there should be a more elegant way to do this?
> >
> > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> > index 4615f62..6070c70 100644
> > --- a/kernel/trace/trace_events_filter.c
> > +++ b/kernel/trace/trace_events_filter.c
> > @@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
> > struct event_filter *filter;
> > struct filter_parse_state *ps;
> > struct ftrace_event_call *call = NULL;
> > + int found = 0;
> >
> > mutex_lock(&event_mutex);
> >
> > list_for_each_entry(call, &ftrace_events, list) {
> > - if (call->id == event_id)
> > + if (call->id == event_id) {
> > + found = 1;
> > break;
> > + }
> > }
> >
> > err = -EINVAL;
> > - if (!call)
>
> if (call == &ftrace_events)
>
Man... That makes my head hurt. It only works because ->list is the
first element in the struct.
We'd need a cast.
Is that really cleaner?
regards,
dan carpenter
> -- Steve
>
> > + if (!found)
> > goto out_unlock;
> >
> > err = -EEXIST;
>
>
> --
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^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [patch] trace: find the correct ftrace event
2010-03-20 13:56 ` Dan Carpenter
@ 2010-03-20 14:07 ` Steven Rostedt
2010-03-20 14:31 ` Dan Carpenter
2010-03-20 14:39 ` [patch v2] " Dan Carpenter
0 siblings, 2 replies; 8+ messages in thread
From: Steven Rostedt @ 2010-03-20 14:07 UTC (permalink / raw)
To: Dan Carpenter
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
On Sat, 2010-03-20 at 16:56 +0300, Dan Carpenter wrote:
> > > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> > > index 4615f62..6070c70 100644
> > > --- a/kernel/trace/trace_events_filter.c
> > > +++ b/kernel/trace/trace_events_filter.c
> > > @@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
> > > struct event_filter *filter;
> > > struct filter_parse_state *ps;
> > > struct ftrace_event_call *call = NULL;
> > > + int found = 0;
> > >
> > > mutex_lock(&event_mutex);
> > >
> > > list_for_each_entry(call, &ftrace_events, list) {
> > > - if (call->id == event_id)
> > > + if (call->id == event_id) {
> > > + found = 1;
> > > break;
> > > + }
> > > }
> > >
> > > err = -EINVAL;
> > > - if (!call)
> >
> > if (call == &ftrace_events)
> >
>
> Man... That makes my head hurt. It only works because ->list is the
> first element in the struct.
>
> We'd need a cast.
Oops, I missed the fact that it was list_*_entry(). That should be:
if (call->list != &ftrace_events)
No cast needed.
>
> Is that really cleaner?
Perhaps not, but I think it is more elegant ;-)
-- Steve
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [patch] trace: find the correct ftrace event
2010-03-20 14:07 ` Steven Rostedt
@ 2010-03-20 14:31 ` Dan Carpenter
2010-03-20 14:39 ` [patch v2] " Dan Carpenter
1 sibling, 0 replies; 8+ messages in thread
From: Dan Carpenter @ 2010-03-20 14:31 UTC (permalink / raw)
To: Steven Rostedt
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
On Sat, Mar 20, 2010 at 10:07:16AM -0400, Steven Rostedt wrote:
> On Sat, 2010-03-20 at 16:56 +0300, Dan Carpenter wrote:
>
> > > > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> > > > index 4615f62..6070c70 100644
> > > > --- a/kernel/trace/trace_events_filter.c
> > > > +++ b/kernel/trace/trace_events_filter.c
> > > > @@ -1388,16 +1388,19 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
> > > > struct event_filter *filter;
> > > > struct filter_parse_state *ps;
> > > > struct ftrace_event_call *call = NULL;
> > > > + int found = 0;
> > > >
> > > > mutex_lock(&event_mutex);
> > > >
> > > > list_for_each_entry(call, &ftrace_events, list) {
> > > > - if (call->id == event_id)
> > > > + if (call->id == event_id) {
> > > > + found = 1;
> > > > break;
> > > > + }
> > > > }
> > > >
> > > > err = -EINVAL;
> > > > - if (!call)
> > >
> > > if (call == &ftrace_events)
> > >
> >
> > Man... That makes my head hurt. It only works because ->list is the
> > first element in the struct.
> >
> > We'd need a cast.
>
> Oops, I missed the fact that it was list_*_entry(). That should be:
>
> if (call->list != &ftrace_events)
>
> No cast needed.
>
Hm... "list" is a struct not a pointer to a struct.
So it would have to be:
if (&call->list == &ftrace_events)
goto out_unlock;
That's how the list_for_each_entry() determines the end of the list as
well.
I'll send a patch to do that.
regards,
dan carpenter
> >
> > Is that really cleaner?
>
> Perhaps not, but I think it is more elegant ;-)
>
> -- Steve
^ permalink raw reply [flat|nested] 8+ messages in thread* [patch v2] trace: find the correct ftrace event
2010-03-20 14:07 ` Steven Rostedt
2010-03-20 14:31 ` Dan Carpenter
@ 2010-03-20 14:39 ` Dan Carpenter
2010-03-21 1:09 ` Steven Rostedt
2010-05-07 18:40 ` [tip:perf/core] perf: Fix check at end of event search tip-bot for Dan Carpenter
1 sibling, 2 replies; 8+ messages in thread
From: Dan Carpenter @ 2010-03-20 14:39 UTC (permalink / raw)
To: Steven Rostedt
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
The original code doesn't work because "call" is never NULL there.
Signed-off-by: Dan Carpenter <error27@gmail.com>
---
The original patch was fine, but this version is more tasteful. ;)
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 4615f62..c1a263a 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1397,7 +1397,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
}
err = -EINVAL;
- if (!call)
+ if (&call->list == &ftrace_events)
goto out_unlock;
err = -EEXIST;
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [patch v2] trace: find the correct ftrace event
2010-03-20 14:39 ` [patch v2] " Dan Carpenter
@ 2010-03-21 1:09 ` Steven Rostedt
2010-05-07 18:40 ` [tip:perf/core] perf: Fix check at end of event search tip-bot for Dan Carpenter
1 sibling, 0 replies; 8+ messages in thread
From: Steven Rostedt @ 2010-03-21 1:09 UTC (permalink / raw)
To: Dan Carpenter
Cc: Ingo Molnar, Frederic Weisbecker, Li Zefan, Tom Zanussi,
linux-kernel, kernel-janitors
On Sat, 2010-03-20 at 17:39 +0300, Dan Carpenter wrote:
> The original code doesn't work because "call" is never NULL there.
>
> Signed-off-by: Dan Carpenter <error27@gmail.com>
Thanks, I'll apply and test this on Monday.
-- Steve
>
> ---
> The original patch was fine, but this version is more tasteful. ;)
>
> diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> index 4615f62..c1a263a 100644
> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -1397,7 +1397,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
> }
>
> err = -EINVAL;
> - if (!call)
> + if (&call->list == &ftrace_events)
> goto out_unlock;
>
> err = -EEXIST;
^ permalink raw reply [flat|nested] 8+ messages in thread
* [tip:perf/core] perf: Fix check at end of event search
2010-03-20 14:39 ` [patch v2] " Dan Carpenter
2010-03-21 1:09 ` Steven Rostedt
@ 2010-05-07 18:40 ` tip-bot for Dan Carpenter
1 sibling, 0 replies; 8+ messages in thread
From: tip-bot for Dan Carpenter @ 2010-05-07 18:40 UTC (permalink / raw)
To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, rostedt, error27, tglx
Commit-ID: d9f599e1e6d019968b35d2dc63074b9e8964fa69
Gitweb: http://git.kernel.org/tip/d9f599e1e6d019968b35d2dc63074b9e8964fa69
Author: Dan Carpenter <error27@gmail.com>
AuthorDate: Sat, 20 Mar 2010 17:39:11 +0300
Committer: Steven Rostedt <rostedt@goodmis.org>
CommitDate: Thu, 6 May 2010 19:49:52 -0400
perf: Fix check at end of event search
The original code doesn't work because "call" is never NULL there.
Signed-off-by: Dan Carpenter <error27@gmail.com>
LKML-Reference: <20100320143911.GF5331@bicker>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace_events_filter.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 88c0b6d..58092d8 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1398,7 +1398,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
}
err = -EINVAL;
- if (!call)
+ if (&call->list == &ftrace_events)
goto out_unlock;
err = -EEXIST;
^ permalink raw reply related [flat|nested] 8+ messages in thread
end of thread, other threads:[~2010-05-07 18:41 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
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2010-03-20 13:19 [patch] trace: find the correct ftrace event Dan Carpenter
2010-03-20 13:37 ` Steven Rostedt
2010-03-20 13:56 ` Dan Carpenter
2010-03-20 14:07 ` Steven Rostedt
2010-03-20 14:31 ` Dan Carpenter
2010-03-20 14:39 ` [patch v2] " Dan Carpenter
2010-03-21 1:09 ` Steven Rostedt
2010-05-07 18:40 ` [tip:perf/core] perf: Fix check at end of event search tip-bot for Dan Carpenter
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