[LTP] [PATCH v2] ltp-aiodio/dio_sparse: Fix usleep in read_sparse()

[Guangwen Feng]

Hi!

On 02/09/2017 05:35 PM, Cyril Hrubis wrote:
> Hi!
>> usleep(100000) sometimes leads to child process being too late
>> to do the read before being killed by parent process, tune it
>> to usleep(100) to make sure we do the real test in time.
>>
>> Signed-off-by: Guangwen Feng <fenggw-fnst@cn.fujitsu.com>
>> ---
>>  testcases/kernel/io/ltp-aiodio/common_sparse.h | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/testcases/kernel/io/ltp-aiodio/common_sparse.h b/testcases/kernel/io/ltp-aiodio/common_sparse.h
>> index f7f4ef4..7297319 100644
>> --- a/testcases/kernel/io/ltp-aiodio/common_sparse.h
>> +++ b/testcases/kernel/io/ltp-aiodio/common_sparse.h
>> @@ -113,7 +113,7 @@ static void read_sparse(char *filename, int filesize)
>>  	/*
>>  	 * Wait for the file to appear.
>>  	 */
>> -	for (i = 0; i < 10000; i++) {
>> +	for (i = 0; i < 10000000; i++) {
>>  		fd = open(filename, O_RDONLY);
>>  
>>  		if (fd != -1)
>> @@ -123,7 +123,7 @@ static void read_sparse(char *filename, int filesize)
>>  			fprintf(stderr, "Child %i waits for '%s' to appear\n",
>>  			        getpid(), filename);
>>  
>> -		usleep(100000);
>> +		usleep(100);
>>  	}
> 
> Looking at the code again, I see no reason why we can't open and
> truncate the file before we start the read_sparse() children, then we
> could drop this loop and just pass file descriptor to this function and
> to the dio_sparse() and aiodio_sparse() as well. Or did I miss
> something?

Yes, you are right, it is a thoroghly solution to this issue,
I will rewrite this according to your suggestion, thanks.

Best Regards,
Guangwen Feng