Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756403Ab3DLPxy (ORCPT ); Fri, 12 Apr 2013 11:53:54 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:21104 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753193Ab3DLPxx (ORCPT ); Fri, 12 Apr 2013 11:53:53 -0400 Message-ID: <51682E08.9050107@parallels.com> Date: Fri, 12 Apr 2013 19:53:44 +0400 From: Pavel Emelyanov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Andrew Morton , Linux MM , Linux Kernel Mailing List Subject: [PATCH 6/5] selftest: Add simple test for soft-dirty bit References: <51669E5F.4000801@parallels.com> <51669EB8.2020102@parallels.com> In-Reply-To: <51669EB8.2020102@parallels.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3737 Lines: 160 It creates a mapping of 3 pages and checks that reads, writes and clear-refs result in present and soft-dirt bits reported from pagemap2 set as expected. Signed-off-by: Pavel Emelyanov --- diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 575ef80..827f2c0 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -6,6 +6,7 @@ TARGETS += cpu-hotplug TARGETS += memory-hotplug TARGETS += efivarfs TARGETS += ptrace +TARGETS += soft-dirty all: for TARGET in $(TARGETS); do \ diff --git a/tools/testing/selftests/soft-dirty/Makefile b/tools/testing/selftests/soft-dirty/Makefile new file mode 100644 index 0000000..a9cdc82 --- /dev/null +++ b/tools/testing/selftests/soft-dirty/Makefile @@ -0,0 +1,10 @@ +CFLAGS += -iquote../../../../include/uapi -Wall +soft-dirty: soft-dirty.c + +all: soft-dirty + +clean: + rm -f soft-dirty + +run_tests: all + @./soft-dirty || echo "soft-dirty selftests: [FAIL]" diff --git a/tools/testing/selftests/soft-dirty/soft-dirty.c b/tools/testing/selftests/soft-dirty/soft-dirty.c new file mode 100644 index 0000000..aba4f87 --- /dev/null +++ b/tools/testing/selftests/soft-dirty/soft-dirty.c @@ -0,0 +1,114 @@ +#include +#include +#include +#include +#include +#include + +typedef unsigned long long u64; + +#define PME_PRESENT (1ULL << 63) +#define PME_SOFT_DIRTY (1Ull << 55) + +#define PAGES_TO_TEST 3 +#ifndef PAGE_SIZE +#define PAGE_SIZE 4096 +#endif + +static void get_pagemap2(char *mem, u64 *map) +{ + int fd; + + fd = open("/proc/self/pagemap2", O_RDONLY); + if (fd < 0) { + perror("Can't open pagemap2"); + exit(1); + } + + lseek(fd, (unsigned long)mem / PAGE_SIZE * sizeof(u64), SEEK_SET); + read(fd, map, sizeof(u64) * PAGES_TO_TEST); + close(fd); +} + +static inline char map_p(u64 map) +{ + return map & PME_PRESENT ? 'p' : '-'; +} + +static inline char map_sd(u64 map) +{ + return map & PME_SOFT_DIRTY ? 'd' : '-'; +} + +static int check_pte(int step, int page, u64 *map, u64 want) +{ + if ((map[page] & want) != want) { + printf("Step %d Page %d has %c%c, want %c%c\n", + step, page, + map_p(map[page]), map_sd(map[page]), + map_p(want), map_sd(want)); + return 1; + } + + return 0; +} + +static void clear_refs(void) +{ + int fd; + char *v = "4"; + + fd = open("/proc/self/clear_refs", O_WRONLY); + if (write(fd, v, 3) < 3) { + perror("Can't clear soft-dirty bit"); + exit(1); + } + close(fd); +} + +int main(void) +{ + char *mem, x; + u64 map[PAGES_TO_TEST]; + + mem = mmap(NULL, PAGES_TO_TEST * PAGE_SIZE, + PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, 0, 0); + + x = mem[0]; + mem[2 * PAGE_SIZE] = 'c'; + get_pagemap2(mem, map); + + if (check_pte(1, 0, map, PME_PRESENT)) + return 1; + if (check_pte(1, 1, map, 0)) + return 1; + if (check_pte(1, 2, map, PME_PRESENT | PME_SOFT_DIRTY)) + return 1; + + clear_refs(); + get_pagemap2(mem, map); + + if (check_pte(2, 0, map, PME_PRESENT)) + return 1; + if (check_pte(2, 1, map, 0)) + return 1; + if (check_pte(2, 2, map, PME_PRESENT)) + return 1; + + mem[0] = 'a'; + mem[PAGE_SIZE] = 'b'; + x = mem[2 * PAGE_SIZE]; + get_pagemap2(mem, map); + + if (check_pte(3, 0, map, PME_PRESENT | PME_SOFT_DIRTY)) + return 1; + if (check_pte(3, 1, map, PME_PRESENT | PME_SOFT_DIRTY)) + return 1; + if (check_pte(3, 2, map, PME_PRESENT)) + return 1; + + (void)x; /* gcc warn */ + + printf("PASS\n"); + return 0; +} -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/