[PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[Gustavo A. R. Silva]

Notice that the use of the bitwise OR operator '|' always leads to
true in this particular case, which seems a bit suspicious due to
the context in which this expression is being used.

Fix this by using bitwise AND operator '&' instead.

This bug was detected with the help of Coccinelle.

Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---

NOTE: Notice that this code has been there since 2012. So, it would
      be helpful if someone can double-check this. Thanks.

 tools/perf/tests/evsel-tp-sched.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/evsel-tp-sched.c b/tools/perf/tests/evsel-tp-sched.c
index 5f8501c68da4..5cbba70bcdd0 100644
--- a/tools/perf/tests/evsel-tp-sched.c
+++ b/tools/perf/tests/evsel-tp-sched.c
@@ -17,7 +17,7 @@ static int perf_evsel__test_field(struct perf_evsel *evsel, const char *name,
 		return -1;
 	}
 
-	is_signed = !!(field->flags | TEP_FIELD_IS_SIGNED);
+	is_signed = !!(field->flags & TEP_FIELD_IS_SIGNED);
 	if (should_be_signed && !is_signed) {
 		pr_debug("%s: \"%s\" signedness(%d) is wrong, should be %d\n",
 			 evsel->name, name, is_signed, should_be_signed);
-- 
2.20.1

Re: [PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[Jiri Olsa]

On Tue, Jan 22, 2019 at 05:34:39PM -0600, Gustavo A. R. Silva wrote:
> Notice that the use of the bitwise OR operator '|' always leads to
> true in this particular case, which seems a bit suspicious due to
> the context in which this expression is being used.
> 
> Fix this by using bitwise AND operator '&' instead.
> 
> This bug was detected with the help of Coccinelle.
> 
> Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
> Cc: stable@vger.kernel.org
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

nice catch

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka


> ---
> 
> NOTE: Notice that this code has been there since 2012. So, it would
>       be helpful if someone can double-check this. Thanks.
> 
>  tools/perf/tests/evsel-tp-sched.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/tests/evsel-tp-sched.c b/tools/perf/tests/evsel-tp-sched.c
> index 5f8501c68da4..5cbba70bcdd0 100644
> --- a/tools/perf/tests/evsel-tp-sched.c
> +++ b/tools/perf/tests/evsel-tp-sched.c
> @@ -17,7 +17,7 @@ static int perf_evsel__test_field(struct perf_evsel *evsel, const char *name,
>  		return -1;
>  	}
>  
> -	is_signed = !!(field->flags | TEP_FIELD_IS_SIGNED);
> +	is_signed = !!(field->flags & TEP_FIELD_IS_SIGNED);
>  	if (should_be_signed && !is_signed) {
>  		pr_debug("%s: \"%s\" signedness(%d) is wrong, should be %d\n",
>  			 evsel->name, name, is_signed, should_be_signed);
> -- 
> 2.20.1
> 

Re: [PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[Gustavo A. R. Silva]

On 1/23/19 2:33 AM, Jiri Olsa wrote:
> On Tue, Jan 22, 2019 at 05:34:39PM -0600, Gustavo A. R. Silva wrote:
>> Notice that the use of the bitwise OR operator '|' always leads to
>> true in this particular case, which seems a bit suspicious due to
>> the context in which this expression is being used.
>>
>> Fix this by using bitwise AND operator '&' instead.
>>
>> This bug was detected with the help of Coccinelle.
>>
>> Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> 
> nice catch
> 

Glad to help. :)

> Acked-by: Jiri Olsa <jolsa@kernel.org>
> 

Thanks
--
Gustavo

> thanks,
> jirka
> 
> 
>> ---
>>
>> NOTE: Notice that this code has been there since 2012. So, it would
>>       be helpful if someone can double-check this. Thanks.
>>
>>  tools/perf/tests/evsel-tp-sched.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/tools/perf/tests/evsel-tp-sched.c b/tools/perf/tests/evsel-tp-sched.c
>> index 5f8501c68da4..5cbba70bcdd0 100644
>> --- a/tools/perf/tests/evsel-tp-sched.c
>> +++ b/tools/perf/tests/evsel-tp-sched.c
>> @@ -17,7 +17,7 @@ static int perf_evsel__test_field(struct perf_evsel *evsel, const char *name,
>>  		return -1;
>>  	}
>>  
>> -	is_signed = !!(field->flags | TEP_FIELD_IS_SIGNED);
>> +	is_signed = !!(field->flags & TEP_FIELD_IS_SIGNED);
>>  	if (should_be_signed && !is_signed) {
>>  		pr_debug("%s: \"%s\" signedness(%d) is wrong, should be %d\n",
>>  			 evsel->name, name, is_signed, should_be_signed);
>> -- 
>> 2.20.1
>>

Re: [PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[Gustavo A. R. Silva]

Hi all,

Friendly ping:

Who can take this?

Thanks
--
Gustavo

On 1/23/19 2:40 AM, Gustavo A. R. Silva wrote:
> 
> 
> On 1/23/19 2:33 AM, Jiri Olsa wrote:
>> On Tue, Jan 22, 2019 at 05:34:39PM -0600, Gustavo A. R. Silva wrote:
>>> Notice that the use of the bitwise OR operator '|' always leads to
>>> true in this particular case, which seems a bit suspicious due to
>>> the context in which this expression is being used.
>>>
>>> Fix this by using bitwise AND operator '&' instead.
>>>
>>> This bug was detected with the help of Coccinelle.
>>>
>>> Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
>>> Cc: stable@vger.kernel.org
>>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
>>
>> nice catch
>>
> 
> Glad to help. :)
> 
>> Acked-by: Jiri Olsa <jolsa@kernel.org>
>>
> 
> Thanks
> --
> Gustavo
> 
>> thanks,
>> jirka
>>
>>
>>> ---
>>>
>>> NOTE: Notice that this code has been there since 2012. So, it would
>>>       be helpful if someone can double-check this. Thanks.
>>>
>>>  tools/perf/tests/evsel-tp-sched.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/tools/perf/tests/evsel-tp-sched.c b/tools/perf/tests/evsel-tp-sched.c
>>> index 5f8501c68da4..5cbba70bcdd0 100644
>>> --- a/tools/perf/tests/evsel-tp-sched.c
>>> +++ b/tools/perf/tests/evsel-tp-sched.c
>>> @@ -17,7 +17,7 @@ static int perf_evsel__test_field(struct perf_evsel *evsel, const char *name,
>>>  		return -1;
>>>  	}
>>>  
>>> -	is_signed = !!(field->flags | TEP_FIELD_IS_SIGNED);
>>> +	is_signed = !!(field->flags & TEP_FIELD_IS_SIGNED);
>>>  	if (should_be_signed && !is_signed) {
>>>  		pr_debug("%s: \"%s\" signedness(%d) is wrong, should be %d\n",
>>>  			 evsel->name, name, is_signed, should_be_signed);
>>> -- 
>>> 2.20.1
>>>

Re: [PATCH] perf tests: evsel-tp-sched: Fix bitwise operator

[Arnaldo Carvalho de Melo]

Em Wed, Jan 23, 2019 at 09:33:38AM +0100, Jiri Olsa escreveu:
> On Tue, Jan 22, 2019 at 05:34:39PM -0600, Gustavo A. R. Silva wrote:
> > Notice that the use of the bitwise OR operator '|' always leads to
> > true in this particular case, which seems a bit suspicious due to
> > the context in which this expression is being used.
> > 
> > Fix this by using bitwise AND operator '&' instead.
> > 
> > This bug was detected with the help of Coccinelle.
> > 
> > Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> 
> nice catch
> 
> Acked-by: Jiri Olsa <jolsa@kernel.org>

Argh, applied, and looking for an old brown paper bag...

- Arnaldo

[tip:perf/urgent] perf tests evsel-tp-sched: Fix bitwise operator

[tip-bot for Gustavo A. R. Silva]

Commit-ID:  489338a717a0dfbbd5a3fabccf172b78f0ac9015
Gitweb:     https://git.kernel.org/tip/489338a717a0dfbbd5a3fabccf172b78f0ac9015
Author:     Gustavo A. R. Silva <gustavo@embeddedor.com>
AuthorDate: Tue, 22 Jan 2019 17:34:39 -0600
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Mon, 4 Feb 2019 11:32:14 -0300

perf tests evsel-tp-sched: Fix bitwise operator

Notice that the use of the bitwise OR operator '|' always leads to true
in this particular case, which seems a bit suspicious due to the context
in which this expression is being used.

Fix this by using bitwise AND operator '&' instead.

This bug was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields")
Link: http://lkml.kernel.org/r/20190122233439.GA5868@embeddedor
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/tests/evsel-tp-sched.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/evsel-tp-sched.c b/tools/perf/tests/evsel-tp-sched.c
index 5f8501c68da4..5cbba70bcdd0 100644
--- a/tools/perf/tests/evsel-tp-sched.c
+++ b/tools/perf/tests/evsel-tp-sched.c
@@ -17,7 +17,7 @@ static int perf_evsel__test_field(struct perf_evsel *evsel, const char *name,
 		return -1;
 	}
 
-	is_signed = !!(field->flags | TEP_FIELD_IS_SIGNED);
+	is_signed = !!(field->flags & TEP_FIELD_IS_SIGNED);
 	if (should_be_signed && !is_signed) {
 		pr_debug("%s: \"%s\" signedness(%d) is wrong, should be %d\n",
 			 evsel->name, name, is_signed, should_be_signed);