Commit d6c27897 authored by Chaitanya S Prakash's avatar Chaitanya S Prakash Committed by Andrew Morton
Browse files

selftests/mm: set overcommit_policy as OVERCOMMIT_ALWAYS 

The kernel's default behaviour is to obstruct the allocation of high
virtual address as it handles memory overcommit in a heuristic manner. 
Setting the parameter as OVERCOMMIT_ALWAYS, ensures kernel isn't
susceptible to the availability of a platform's physical memory when
denying a memory allocation request.

Link: https://lkml.kernel.org/r/20230323060121.1175830-4-chaitanyas.prakash@arm.com


Signed-off-by: default avatarChaitanya S Prakash <chaitanyas.prakash@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 3f9bea2b

tools/testing/selftests/mm/run_vmtests.sh

+8 −0
Original line number Diff line number Diff line
@@ -220,7 +220,15 @@ CATEGORY="mremap" run_test ./mremap_test 
CATEGORY="hugetlb" run_test ./thuge-gen



if [ $VADDR64 -ne 0 ]; then



	# set overcommit_policy as OVERCOMMIT_ALWAYS so that kernel

	# allows high virtual address allocation requests independent

	# of platform's physical memory.



	prev_policy=$(cat /proc/sys/vm/overcommit_memory)

	echo 1 > /proc/sys/vm/overcommit_memory

	CATEGORY="hugevm" run_test ./virtual_address_range

	echo $prev_policy > /proc/sys/vm/overcommit_memory



	# virtual address 128TB switch test

	CATEGORY="hugevm" run_test ./va_128TBswitch.sh