Commit 1defa8d2 authored Mar 14, 2024 by Ryan Roberts Committed by Kefeng Wang Mar 14, 2024

selftests/mm/kugepaged: restore thp settings at exit

mainline inclusion
from mainline-v6.8-rc1
commit b6aab3384cafba151c53d3b5f7e1f8d073aadf03
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I98AW9
CVE: NA

-------------------------------------------------

Previously, the saved thp settings would be restored upon a signal or at
the natural end of the test suite.  But there are some tests that directly
call exit() upon failure.  In this case, the thp settings were not being
restored, which could then influence other tests.

Fix this by installing an atexit() handler to do the actual restore.  The
signal handler can now just call exit() and the atexit handler is invoked.

Link: https://lkml.kernel.org/r/20231207161211.2374093-6-ryan.roberts@arm.com


Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Barry Song <v-songbaohua@oppo.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Itaru Kitayama <itaru.kitayama@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit b6aab3384cafba151c53d3b5f7e1f8d073aadf03)
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

parent ba572bea

tools/testing/selftests/mm/khugepaged.c

+11 −6

Original line number	Diff line number	Diff line
		@@ -374,18 +374,22 @@ static void pop_settings(void)
		write_settings(current_settings());
		}

		static void restore_settings(int sig)
		static void restore_settings_atexit(void)
		{
		if (skip_settings_restore)
		goto out;
		return;

		printf("Restore THP and khugepaged settings...");
		write_settings(&saved_settings);
		success("OK");
		if (sig)
		exit(EXIT_FAILURE);
		out:
		exit(exit_status);

		skip_settings_restore = true;
		}

		static void restore_settings(int sig)
		{
		/* exit() will invoke the restore_settings_atexit handler. */
		exit(sig ? EXIT_FAILURE : exit_status);
		}

		static void save_settings(void)
		@@ -415,6 +419,7 @@ static void save_settings(void)

		success("OK");

		atexit(restore_settings_atexit);
		signal(SIGTERM, restore_settings);
		signal(SIGINT, restore_settings);
		signal(SIGHUP, restore_settings);