Commit 9c54c522 authored by Muchun Song's avatar Muchun Song Committed by Andrew Morton
Browse files

mm: hugetlb_vmemmap: use kstrtobool for hugetlb_vmemmap param parsing 

Use kstrtobool rather than open coding "on" and "off" parsing in
mm/hugetlb_vmemmap.c, which is more powerful to handle all kinds of
parameters like 'Yy1Nn0' or [oO][NnFf] for "on" and "off".

Link: https://lkml.kernel.org/r/20220512041142.39501-4-songmuchun@bytedance.com


Signed-off-by: default avatarMuchun Song <songmuchun@bytedance.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 6e02c46b

Documentation/admin-guide/kernel-parameters.txt

+3 −3
Original line number Diff line number Diff line
@@ -1664,10 +1664,10 @@ 
			enabled.

			Allows heavy hugetlb users to free up some more

			memory (7 * PAGE_SIZE for each 2MB hugetlb page).

			Format: { on | off (default) }

			Format: { [oO][Nn]/Y/y/1 | [oO][Ff]/N/n/0 (default) }



			on:  enable the feature

			off: disable the feature

			[oO][Nn]/Y/y/1: enable the feature

			[oO][Ff]/N/n/0: disable the feature



			Built with CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON=y,

			the default is on.

mm/hugetlb_vmemmap.c

+5 −5
Original line number Diff line number Diff line
@@ -28,15 +28,15 @@ EXPORT_SYMBOL(hugetlb_optimize_vmemmap_key); 


static int __init hugetlb_vmemmap_early_param(char *buf)

{

	if (!buf)

	bool enable;



	if (kstrtobool(buf, &enable))

		return -EINVAL;



	if (!strcmp(buf, "on"))

	if (enable)

		static_branch_enable(&hugetlb_optimize_vmemmap_key);

	else if (!strcmp(buf, "off"))

		static_branch_disable(&hugetlb_optimize_vmemmap_key);

	else

		return -EINVAL;

		static_branch_disable(&hugetlb_optimize_vmemmap_key);



	return 0;

}