[LTP] [PATCH] memcg_subgroup_charge: Remove memory limitation

[Joerg Vehlow]

Hi,

a little ping for this patch?
I recently updated the ltp suite for our tests to 20200930 and stumbled 
over this error again.
Any reason for not applying it?

Jörg

On 11/6/2019 7:18 AM, Joerg Vehlow wrote:
> From: Joerg Vehlow <joerg.vehlow@aox-tech.de>
>
> The test is supposed to verify, that memory used by a task
> is not migrated to a subgroup, when the task is migrated.
> In order to test this, it is not required, to limit
> the memory at all, because accounting is done anyway and
> the test checks the memory statistics.
>
> Therefore all memory limiting is removed. This also gets
> rid of a faulty assumption when writing the test:
> The test allocates 33 pages using mmap. It is expected,
> that it does not need more than 33 * pagesize of memory.
> But sometimes the kernel has to allocate new page tables.
> This is accounted as kmem AND user memory.
> (See kernel doc cgroup-v1/memory.txt section 2.7)
> If this happend, the test failed, if the system has no swap,
> because the oom killer kills the process.
>
> Signed-off-by: Joerg Vehlow <joerg.vehlow@aox-tech.de>
> ---
>   .../kernel/controllers/memcg/functional/memcg_lib.sh |  4 ----
>   .../memcg/functional/memcg_subgroup_charge.sh        | 12 +-----------
>   2 files changed, 1 insertion(+), 15 deletions(-)
>
> diff --git a/testcases/kernel/controllers/memcg/functional/memcg_lib.sh b/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
> index aadaae4d2..aec8a00ab 100755
> --- a/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
> +++ b/testcases/kernel/controllers/memcg/functional/memcg_lib.sh
> @@ -404,13 +404,9 @@ test_hugepage()
>   }
>   
>   # Test the memory charge won't move to subgroup
> -# $1 - memory.limit_in_bytes in parent group
> -# $2 - memory.limit_in_bytes in sub group
>   test_subgroup()
>   {
>   	mkdir subgroup
> -	echo $1 > memory.limit_in_bytes
> -	echo $2 > subgroup/memory.limit_in_bytes
>   
>   	tst_resm TINFO "Running memcg_process --mmap-anon -s $PAGESIZES"
>   	memcg_process --mmap-anon -s $PAGESIZES &
> diff --git a/testcases/kernel/controllers/memcg/functional/memcg_subgroup_charge.sh b/testcases/kernel/controllers/memcg/functional/memcg_subgroup_charge.sh
> index 9b11f7b58..98e5ad68d 100755
> --- a/testcases/kernel/controllers/memcg/functional/memcg_subgroup_charge.sh
> +++ b/testcases/kernel/controllers/memcg/functional/memcg_subgroup_charge.sh
> @@ -26,7 +26,7 @@
>   ################################################################################
>   
>   TCID="memcg_subgroup_charge"
> -TST_TOTAL=3
> +TST_TOTAL=1
>   
>   . memcg_lib.sh
>   
> @@ -36,15 +36,5 @@ testcase_1()
>   	test_subgroup $PAGESIZES $((2*PAGESIZES))
>   }
>   
> -testcase_2()
> -{
> -	test_subgroup $PAGESIZES $PAGESIZES
> -}
> -
> -testcase_3()
> -{
> -	test_subgroup $PAGESIZES 0
> -}
> -
>   run_tests
>   tst_exit