[LTP] [PATCH RFC 1/3] min_free_kbytes: Fix child exit status check conditions

[Jan Stancek <jstancek@redhat.com>]

----- Original Message -----
> From: Vipin K Parashar <vipin@linux.vnet.ibm.com>
> 
> Fixes: #349
> 
> min_free_kbytes test has badly formed if conditions in mem_tune()
> for child exit status check. 

Can you please elaborate what's wrong about it?

> This is causing test to declare as FAILED
> despite that not being the case.

Why? Shouldn't mmap succeed with overcommit == 1?

> Fix child exit status check conditions.
> 
> ---ERROR LOG---
> <..snip..>
> mem.c:839: INFO: set overcommit_memory to 1
> mem.c:839: INFO: set min_free_kbytes to 11580
> memfree is 6974720 kB before eatup mem
> memfree is 15488 kB after eatup mem
> min_free_kbytes.c:135: FAIL: child unexpectedly failed: 0
> mem.c:839: INFO: set min_free_kbytes to 23160
> memfree is 7104128 kB before eatup mem
> memfree is 26560 kB after eatup mem
> min_free_kbytes.c:135: FAIL: child unexpectedly failed: 0
> mem.c:839: INFO: set min_free_kbytes to 145812
> memfree is 7101504 kB before eatup mem
> memfree is 215872 kB after eatup mem
> min_free_kbytes.c:135: FAIL: child unexpectedly failed: 0
> min_free_kbytes.c:81: PASS: min_free_kbytes test pass
> mem.c:839: INFO: set min_free_kbytes to 11580
> ---------------
> 
> Signed-off-by: Vipin K Parashar <vipin@linux.vnet.ibm.com>
> Signed-off-by: Li Wang <liwang@redhat.com>
> Cc: Jan Stancek <jstancek@redhat.com>
> ---
>  .../kernel/mem/tunable/min_free_kbytes.c      | 40 +++++--------------
>  1 file changed, 11 insertions(+), 29 deletions(-)
> 
> diff --git a/testcases/kernel/mem/tunable/min_free_kbytes.c
> b/testcases/kernel/mem/tunable/min_free_kbytes.c
> index f114dc493..d2378a700 100644
> --- a/testcases/kernel/mem/tunable/min_free_kbytes.c
> +++ b/testcases/kernel/mem/tunable/min_free_kbytes.c
> @@ -119,39 +119,21 @@ static void test_tune(unsigned long overcommit_policy)
>  
>  		SAFE_WAITPID(pid[i], &status, WUNTRACED | WCONTINUED);
>  
> -		if (overcommit_policy == 2) {
> -			if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
> -				tst_res(TFAIL,
> -					 "child unexpectedly failed: %d",
> -					 status);
> -		} else if (overcommit_policy == 1) {
> -			if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGKILL)
> +		if (WIFEXITED(status) && WEXITSTATUS(status) != 0) {
> +			tst_res(TFAIL,
> +				"child unexpectedly failed: %d", status);
> +		} else if (WIFSIGNALED(status) && WTERMSIG(status) != SIGKILL) {
>  #if __WORDSIZE == 32
> -			{
> -				if (total_mem < 3145728UL)
> +			if (total_mem < 3145728UL)
>  #endif
> -					tst_res(TFAIL,
> -						 "child unexpectedly failed: %d",
> -						 status);
> +				tst_res(TFAIL,
> +					"child unexpectedly failed: %d", status);
>  #if __WORDSIZE == 32
> -				/* in 32-bit system, a process allocate about 3Gb memory at most */
> -				else
> -					tst_res(TINFO, "Child can't allocate "
> -						 ">3Gb memory in 32bit system");
> -			}
> +			/* in 32-bit system, a process allocate about 3Gb memory at most */
> +			else
> +				tst_res(TINFO, "Child can't allocate "
> +					">3Gb memory in 32bit system");
>  #endif
> -		} else {
> -			if (WIFEXITED(status)) {
> -				if (WEXITSTATUS(status) != 0) {
> -					tst_res(TFAIL, "child unexpectedly "
> -						 "failed: %d", status);
> -				}
> -			} else if (!WIFSIGNALED(status) ||
> -				   WTERMSIG(status) != SIGKILL) {
> -				tst_res(TFAIL,
> -					 "child unexpectedly failed: %d",
> -					 status);
> -			}
>  		}
>  	}
>  }
> --
> 2.20.1
> 
>