Commit 1448d4d8 authored by Simon Guo's avatar Simon Guo Committed by Linus Torvalds
Browse files

selftests/vm: add test for mlock() when areas are intersected 

This patch adds mlock() test for multiple invocation on the same address
area, and verify it doesn't mess the rlimit mlock limitation.

Link: http://lkml.kernel.org/r/1472554781-9835-5-git-send-email-wei.guo.simon@gmail.com


Signed-off-by: default avatarSimon Guo <wei.guo.simon@gmail.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Eric B Munson <emunson@akamai.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Simon Guo <wei.guo.simon@gmail.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c7f032bb

tools/testing/selftests/vm/.gitignore

+1 −0
Original line number Diff line number Diff line
@@ -7,3 +7,4 @@ mlock2-tests 
on-fault-limit

transhuge-stress

userfaultfd

mlock-intersect-test

tools/testing/selftests/vm/Makefile

+4 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ BINARIES += on-fault-limit 
BINARIES += thuge-gen

BINARIES += transhuge-stress

BINARIES += userfaultfd

BINARIES += mlock-intersect-test



all: $(BINARIES)

%: %.c
@@ -17,6 +18,9 @@ all: $(BINARIES) 
userfaultfd: userfaultfd.c ../../../../usr/include/linux/kernel.h

	$(CC) $(CFLAGS) -O2 -o $@ $< -lpthread



mlock-intersect-test: mlock-intersect-test.c

	$(CC) $(CFLAGS) -o $@ $< -lcap



../../../../usr/include/linux/kernel.h:

	make -C ../../../.. headers_install

tools/testing/selftests/vm/mlock-intersect-test.c

0 → 100644
+76 −0
Original line number Diff line number Diff line 
/*

 * It tests the duplicate mlock result:

 * - the ulimit of lock page is 64k

 * - allocate address area 64k starting from p

 * - mlock   [p -- p + 30k]

 * - Then mlock address  [ p -- p + 40k ]

 *

 * It should succeed since totally we locked

 * 40k < 64k limitation.

 *

 * It should not be run with CAP_IPC_LOCK.

 */

#include <stdlib.h>

#include <stdio.h>

#include <unistd.h>

#include <sys/resource.h>

#include <sys/capability.h>

#include <sys/mman.h>

#include "mlock2.h"



int main(int argc, char **argv)

{

	struct rlimit new;

	char *p = NULL;

	cap_t cap = cap_init();

	int i;



	/* drop capabilities including CAP_IPC_LOCK */

	if (cap_set_proc(cap))

		return -1;



	/* set mlock limits to 64k */

	new.rlim_cur = 65536;

	new.rlim_max = 65536;

	setrlimit(RLIMIT_MEMLOCK, &new);



	/* test VM_LOCK */

	p = malloc(1024 * 64);

	if (mlock(p, 1024 * 30)) {

		printf("mlock() 30k return failure.\n");

		return -1;

	}

	for (i = 0; i < 10; i++) {

		if (mlock(p, 1024 * 40)) {

			printf("mlock() #%d 40k returns failure.\n", i);

			return -1;

		}

	}

	for (i = 0; i < 10; i++) {

		if (mlock2_(p, 1024 * 40, MLOCK_ONFAULT)) {

			printf("mlock2_() #%d 40k returns failure.\n", i);

			return -1;

		}

	}

	free(p);



	/* Test VM_LOCKONFAULT */

	p = malloc(1024 * 64);

	if (mlock2_(p, 1024 * 30, MLOCK_ONFAULT)) {

		printf("mlock2_() 30k return failure.\n");

		return -1;

	}

	for (i = 0; i < 10; i++) {

		if (mlock2_(p, 1024 * 40, MLOCK_ONFAULT)) {

			printf("mlock2_() #%d 40k returns failure.\n", i);

			return -1;

		}

	}

	for (i = 0; i < 10; i++) {

		if (mlock(p, 1024 * 40)) {

			printf("mlock() #%d 40k returns failure.\n", i);

			return -1;

		}

	}

	return 0;

}

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