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Subject: Re: [PATCH 1/2] kernel-shark-qt: Deal with the "no tasks" case in
 kshark_get_task_pids()
From: "Yordan Karadzhov (VMware)" <y.karadz@gmail.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-trace-devel@vger.kernel.org
References: <20180711133709.26788-1-y.karadz@gmail.com>
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 <87c21cdd-b259-2be3-9fdb-9f471fc37cb5@gmail.com>
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Date: Fri, 3 Aug 2018 16:06:24 +0300
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Hi Steven,
Should I send this patch again?

Thanks!
Yordan


On 11.07.2018 17:08, Yordan Karadzhov (VMware) wrote:
>>
>> What about doing it this way:
>>
>> diff --git a/kernel-shark-qt/src/libkshark.c 
>> b/kernel-shark-qt/src/libkshark.c
>> index 668b6df8..34daa25e 100644
>> --- a/kernel-shark-qt/src/libkshark.c
>> +++ b/kernel-shark-qt/src/libkshark.c
>> @@ -303,12 +303,17 @@ ssize_t kshark_get_task_pids(struct 
>> kshark_context *kshark_ctx, int **pids)
>>           }
>>       }
>> -    temp_pids = realloc(*pids, pid_count * sizeof(int));
>> -    if (!temp_pids)
>> -        goto fail;
>> +    if (pid_count) {
>> +        temp_pids = realloc(*pids, pid_count * sizeof(int));
>> +        if (!temp_pids)
>> +            goto fail;
>> -    /* Paranoid: In the unlikely case of shrinking *pids, realloc 
>> moves it */
>> -    *pids = temp_pids;
>> +        /* Paranoid: In the unlikely case of shrinking *pids, realloc 
>> moves it */
>> +        *pids = temp_pids;
>> +    } else {
>> +        free(*pids);
>> +        *pids = NULL;
>> +    }
>>       return pid_count;
> 
> Yes, this way is better.
> 
> Thanks!
> Yordan
> 
> 
>>
>> ?
>>
>> -- Steve