From: Simon Guo <wei.guo.simon@xxxxxxxxx> Subject: 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@xxxxxxxxx Signed-off-by: Simon Guo <wei.guo.simon@xxxxxxxxx> Cc: Alexey Klimov <klimov.linux@xxxxxxxxx> Cc: Eric B Munson <emunson@xxxxxxxxxx> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Simon Guo <wei.guo.simon@xxxxxxxxx> Cc: Thierry Reding <treding@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/.gitignore | 1 tools/testing/selftests/vm/Makefile | 4 tools/testing/selftests/vm/mlock-intersect-test.c | 76 ++++++++++++ 3 files changed, 81 insertions(+) diff -puN tools/testing/selftests/vm/.gitignore~selftests-vm-add-test-for-mlock-when-areas-are-intersected tools/testing/selftests/vm/.gitignore --- a/tools/testing/selftests/vm/.gitignore~selftests-vm-add-test-for-mlock-when-areas-are-intersected +++ a/tools/testing/selftests/vm/.gitignore @@ -7,3 +7,4 @@ mlock2-tests on-fault-limit transhuge-stress userfaultfd +mlock-intersect-test diff -puN tools/testing/selftests/vm/Makefile~selftests-vm-add-test-for-mlock-when-areas-are-intersected tools/testing/selftests/vm/Makefile --- a/tools/testing/selftests/vm/Makefile~selftests-vm-add-test-for-mlock-when-areas-are-intersected +++ a/tools/testing/selftests/vm/Makefile @@ -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 diff -puN /dev/null tools/testing/selftests/vm/mlock-intersect-test.c --- /dev/null +++ a/tools/testing/selftests/vm/mlock-intersect-test.c @@ -0,0 +1,76 @@ +/* + * 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; +} _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
