Re: [PATCH] perf stat: Fix error return code in bperf__load()

["yukuai (C)" <yukuai3@huawei.com>]

On 2021/06/01 21:55, Arnaldo Carvalho de Melo wrote:
> Em Tue, Jun 01, 2021 at 10:52:42AM -0300, Arnaldo Carvalho de Melo escreveu:
>> Em Mon, May 17, 2021 at 04:12:54PM +0800, Yu Kuai escreveu:
>>> Fix to return a negative error code from the error handling
>>> case instead of 0, as done elsewhere in this function.
>>>
>>> Reported-by: Hulk Robot <hulkci@huawei.com>
>>> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
>>
>> Applied, but I had to add Song to the CC list and also add this line:
>>
>> Fixes: 7fac83aaf2eecc9e ("perf stat: Introduce 'bperf' to share hardware PMCs with BPF")
>>
>> So that the stable@kernel.org folks can get this auto-collected.
>>
>> Perhaps you guys can make Hulk do that as well? :-)
>>
>> Thanks,
> 
> Something else to teach Hulk:
> 
> util/bpf_counter.c: In function ‘bperf__load’:
> util/bpf_counter.c:523:9: error: this ‘if’ clause does not guard... [-Werror=misleading-indentation]
>    523 |         if (evsel->bperf_leader_link_fd < 0 &&
>        |         ^~
> util/bpf_counter.c:526:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
>    526 |                 goto out;
>        |                 ^~~~
> cc1: all warnings being treated as errors
> 
> I'm adding the missing {} for the now multiline if block.
Sorry for the mistake, and similar errors will be checked in the future.

Thanks
Yu Kuai
> 
> - Arnaldo
>>
>>> ---
>>>   tools/perf/util/bpf_counter.c | 2 ++
>>>   1 file changed, 2 insertions(+)
>>>
>>> diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
>>> index ddb52f748c8e..843b20aa6688 100644
>>> --- a/tools/perf/util/bpf_counter.c
>>> +++ b/tools/perf/util/bpf_counter.c
>>> @@ -522,6 +522,7 @@ static int bperf__load(struct evsel *evsel, struct target *target)
>>>   	evsel->bperf_leader_link_fd = bpf_link_get_fd_by_id(entry.link_id);
>>>   	if (evsel->bperf_leader_link_fd < 0 &&
>>>   	    bperf_reload_leader_program(evsel, attr_map_fd, &entry))
>>> +		err = -1;
>>>   		goto out;
>>>   
>>>   	/*
>>> @@ -550,6 +551,7 @@ static int bperf__load(struct evsel *evsel, struct target *target)
>>>   	/* Step 2: load the follower skeleton */
>>>   	evsel->follower_skel = bperf_follower_bpf__open();
>>>   	if (!evsel->follower_skel) {
>>> +		err = -1;
>>>   		pr_err("Failed to open follower skeleton\n");
>>>   		goto out;
>>>   	}
>>> -- 
>>> 2.25.4
>>>
>>
>> -- 
>>
>> - Arnaldo
>