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-rw-r--r--tools/testing/selftests/Makefile1
-rw-r--r--tools/testing/selftests/cgroup/.gitignore1
-rw-r--r--tools/testing/selftests/cgroup/Makefile2
-rw-r--r--tools/testing/selftests/cgroup/cgroup_util.c2
-rw-r--r--tools/testing/selftests/cgroup/test_kmem.c382
-rw-r--r--tools/testing/selftests/mincore/.gitignore2
-rw-r--r--tools/testing/selftests/mincore/Makefile6
-rw-r--r--tools/testing/selftests/mincore/mincore_selftest.c361
8 files changed, 756 insertions, 1 deletions
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index e03bc15ce731..9018f45d631d 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -32,6 +32,7 @@ TARGETS += lkdtm
TARGETS += membarrier
TARGETS += memfd
TARGETS += memory-hotplug
+TARGETS += mincore
TARGETS += mount
TARGETS += mqueue
TARGETS += net
diff --git a/tools/testing/selftests/cgroup/.gitignore b/tools/testing/selftests/cgroup/.gitignore
index aa6de65b0838..84cfcabea838 100644
--- a/tools/testing/selftests/cgroup/.gitignore
+++ b/tools/testing/selftests/cgroup/.gitignore
@@ -2,3 +2,4 @@
test_memcontrol
test_core
test_freezer
+test_kmem \ No newline at end of file
diff --git a/tools/testing/selftests/cgroup/Makefile b/tools/testing/selftests/cgroup/Makefile
index 967f268fde74..f027d933595b 100644
--- a/tools/testing/selftests/cgroup/Makefile
+++ b/tools/testing/selftests/cgroup/Makefile
@@ -6,11 +6,13 @@ all:
TEST_FILES := with_stress.sh
TEST_PROGS := test_stress.sh
TEST_GEN_PROGS = test_memcontrol
+TEST_GEN_PROGS += test_kmem
TEST_GEN_PROGS += test_core
TEST_GEN_PROGS += test_freezer
include ../lib.mk
$(OUTPUT)/test_memcontrol: cgroup_util.c ../clone3/clone3_selftests.h
+$(OUTPUT)/test_kmem: cgroup_util.c ../clone3/clone3_selftests.h
$(OUTPUT)/test_core: cgroup_util.c ../clone3/clone3_selftests.h
$(OUTPUT)/test_freezer: cgroup_util.c ../clone3/clone3_selftests.h
diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c
index 8a637ca7d73a..05853b0b8831 100644
--- a/tools/testing/selftests/cgroup/cgroup_util.c
+++ b/tools/testing/selftests/cgroup/cgroup_util.c
@@ -106,7 +106,7 @@ int cg_read_strcmp(const char *cgroup, const char *control,
/* Handle the case of comparing against empty string */
if (!expected)
- size = 32;
+ return -1;
else
size = strlen(expected) + 1;
diff --git a/tools/testing/selftests/cgroup/test_kmem.c b/tools/testing/selftests/cgroup/test_kmem.c
new file mode 100644
index 000000000000..5224dae216e5
--- /dev/null
+++ b/tools/testing/selftests/cgroup/test_kmem.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+
+#include <linux/limits.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <sys/sysinfo.h>
+#include <pthread.h>
+
+#include "../kselftest.h"
+#include "cgroup_util.h"
+
+
+static int alloc_dcache(const char *cgroup, void *arg)
+{
+ unsigned long i;
+ struct stat st;
+ char buf[128];
+
+ for (i = 0; i < (unsigned long)arg; i++) {
+ snprintf(buf, sizeof(buf),
+ "/something-non-existent-with-a-long-name-%64lu-%d",
+ i, getpid());
+ stat(buf, &st);
+ }
+
+ return 0;
+}
+
+/*
+ * This test allocates 100000 of negative dentries with long names.
+ * Then it checks that "slab" in memory.stat is larger than 1M.
+ * Then it sets memory.high to 1M and checks that at least 1/2
+ * of slab memory has been reclaimed.
+ */
+static int test_kmem_basic(const char *root)
+{
+ int ret = KSFT_FAIL;
+ char *cg = NULL;
+ long slab0, slab1, current;
+
+ cg = cg_name(root, "kmem_basic_test");
+ if (!cg)
+ goto cleanup;
+
+ if (cg_create(cg))
+ goto cleanup;
+
+ if (cg_run(cg, alloc_dcache, (void *)100000))
+ goto cleanup;
+
+ slab0 = cg_read_key_long(cg, "memory.stat", "slab ");
+ if (slab0 < (1 << 20))
+ goto cleanup;
+
+ cg_write(cg, "memory.high", "1M");
+ slab1 = cg_read_key_long(cg, "memory.stat", "slab ");
+ if (slab1 <= 0)
+ goto cleanup;
+
+ current = cg_read_long(cg, "memory.current");
+ if (current <= 0)
+ goto cleanup;
+
+ if (slab1 < slab0 / 2 && current < slab0 / 2)
+ ret = KSFT_PASS;
+cleanup:
+ cg_destroy(cg);
+ free(cg);
+
+ return ret;
+}
+
+static void *alloc_kmem_fn(void *arg)
+{
+ alloc_dcache(NULL, (void *)100);
+ return NULL;
+}
+
+static int alloc_kmem_smp(const char *cgroup, void *arg)
+{
+ int nr_threads = 2 * get_nprocs();
+ pthread_t *tinfo;
+ unsigned long i;
+ int ret = -1;
+
+ tinfo = calloc(nr_threads, sizeof(pthread_t));
+ if (tinfo == NULL)
+ return -1;
+
+ for (i = 0; i < nr_threads; i++) {
+ if (pthread_create(&tinfo[i], NULL, &alloc_kmem_fn,
+ (void *)i)) {
+ free(tinfo);
+ return -1;
+ }
+ }
+
+ for (i = 0; i < nr_threads; i++) {
+ ret = pthread_join(tinfo[i], NULL);
+ if (ret)
+ break;
+ }
+
+ free(tinfo);
+ return ret;
+}
+
+static int cg_run_in_subcgroups(const char *parent,
+ int (*fn)(const char *cgroup, void *arg),
+ void *arg, int times)
+{
+ char *child;
+ int i;
+
+ for (i = 0; i < times; i++) {
+ child = cg_name_indexed(parent, "child", i);
+ if (!child)
+ return -1;
+
+ if (cg_create(child)) {
+ cg_destroy(child);
+ free(child);
+ return -1;
+ }
+
+ if (cg_run(child, fn, NULL)) {
+ cg_destroy(child);
+ free(child);
+ return -1;
+ }
+
+ cg_destroy(child);
+ free(child);
+ }
+
+ return 0;
+}
+
+/*
+ * The test creates and destroys a large number of cgroups. In each cgroup it
+ * allocates some slab memory (mostly negative dentries) using 2 * NR_CPUS
+ * threads. Then it checks the sanity of numbers on the parent level:
+ * the total size of the cgroups should be roughly equal to
+ * anon + file + slab + kernel_stack.
+ */
+static int test_kmem_memcg_deletion(const char *root)
+{
+ long current, slab, anon, file, kernel_stack, sum;
+ int ret = KSFT_FAIL;
+ char *parent;
+
+ parent = cg_name(root, "kmem_memcg_deletion_test");
+ if (!parent)
+ goto cleanup;
+
+ if (cg_create(parent))
+ goto cleanup;
+
+ if (cg_write(parent, "cgroup.subtree_control", "+memory"))
+ goto cleanup;
+
+ if (cg_run_in_subcgroups(parent, alloc_kmem_smp, NULL, 100))
+ goto cleanup;
+
+ current = cg_read_long(parent, "memory.current");
+ slab = cg_read_key_long(parent, "memory.stat", "slab ");
+ anon = cg_read_key_long(parent, "memory.stat", "anon ");
+ file = cg_read_key_long(parent, "memory.stat", "file ");
+ kernel_stack = cg_read_key_long(parent, "memory.stat", "kernel_stack ");
+ if (current < 0 || slab < 0 || anon < 0 || file < 0 ||
+ kernel_stack < 0)
+ goto cleanup;
+
+ sum = slab + anon + file + kernel_stack;
+ if (abs(sum - current) < 4096 * 32 * 2 * get_nprocs()) {
+ ret = KSFT_PASS;
+ } else {
+ printf("memory.current = %ld\n", current);
+ printf("slab + anon + file + kernel_stack = %ld\n", sum);
+ printf("slab = %ld\n", slab);
+ printf("anon = %ld\n", anon);
+ printf("file = %ld\n", file);
+ printf("kernel_stack = %ld\n", kernel_stack);
+ }
+
+cleanup:
+ cg_destroy(parent);
+ free(parent);
+
+ return ret;
+}
+
+/*
+ * The test reads the entire /proc/kpagecgroup. If the operation went
+ * successfully (and the kernel didn't panic), the test is treated as passed.
+ */
+static int test_kmem_proc_kpagecgroup(const char *root)
+{
+ unsigned long buf[128];
+ int ret = KSFT_FAIL;
+ ssize_t len;
+ int fd;
+
+ fd = open("/proc/kpagecgroup", O_RDONLY);
+ if (fd < 0)
+ return ret;
+
+ do {
+ len = read(fd, buf, sizeof(buf));
+ } while (len > 0);
+
+ if (len == 0)
+ ret = KSFT_PASS;
+
+ close(fd);
+ return ret;
+}
+
+static void *pthread_wait_fn(void *arg)
+{
+ sleep(100);
+ return NULL;
+}
+
+static int spawn_1000_threads(const char *cgroup, void *arg)
+{
+ int nr_threads = 1000;
+ pthread_t *tinfo;
+ unsigned long i;
+ long stack;
+ int ret = -1;
+
+ tinfo = calloc(nr_threads, sizeof(pthread_t));
+ if (tinfo == NULL)
+ return -1;
+
+ for (i = 0; i < nr_threads; i++) {
+ if (pthread_create(&tinfo[i], NULL, &pthread_wait_fn,
+ (void *)i)) {
+ free(tinfo);
+ return(-1);
+ }
+ }
+
+ stack = cg_read_key_long(cgroup, "memory.stat", "kernel_stack ");
+ if (stack >= 4096 * 1000)
+ ret = 0;
+
+ free(tinfo);
+ return ret;
+}
+
+/*
+ * The test spawns a process, which spawns 1000 threads. Then it checks
+ * that memory.stat's kernel_stack is at least 1000 pages large.
+ */
+static int test_kmem_kernel_stacks(const char *root)
+{
+ int ret = KSFT_FAIL;
+ char *cg = NULL;
+
+ cg = cg_name(root, "kmem_kernel_stacks_test");
+ if (!cg)
+ goto cleanup;
+
+ if (cg_create(cg))
+ goto cleanup;
+
+ if (cg_run(cg, spawn_1000_threads, NULL))
+ goto cleanup;
+
+ ret = KSFT_PASS;
+cleanup:
+ cg_destroy(cg);
+ free(cg);
+
+ return ret;
+}
+
+/*
+ * This test sequentionally creates 30 child cgroups, allocates some
+ * kernel memory in each of them, and deletes them. Then it checks
+ * that the number of dying cgroups on the parent level is 0.
+ */
+static int test_kmem_dead_cgroups(const char *root)
+{
+ int ret = KSFT_FAIL;
+ char *parent;
+ long dead;
+ int i;
+
+ parent = cg_name(root, "kmem_dead_cgroups_test");
+ if (!parent)
+ goto cleanup;
+
+ if (cg_create(parent))
+ goto cleanup;
+
+ if (cg_write(parent, "cgroup.subtree_control", "+memory"))
+ goto cleanup;
+
+ if (cg_run_in_subcgroups(parent, alloc_dcache, (void *)100, 30))
+ goto cleanup;
+
+ for (i = 0; i < 5; i++) {
+ dead = cg_read_key_long(parent, "cgroup.stat",
+ "nr_dying_descendants ");
+ if (dead == 0) {
+ ret = KSFT_PASS;
+ break;
+ }
+ /*
+ * Reclaiming cgroups might take some time,
+ * let's wait a bit and repeat.
+ */
+ sleep(1);
+ }
+
+cleanup:
+ cg_destroy(parent);
+ free(parent);
+
+ return ret;
+}
+
+#define T(x) { x, #x }
+struct kmem_test {
+ int (*fn)(const char *root);
+ const char *name;
+} tests[] = {
+ T(test_kmem_basic),
+ T(test_kmem_memcg_deletion),
+ T(test_kmem_proc_kpagecgroup),
+ T(test_kmem_kernel_stacks),
+ T(test_kmem_dead_cgroups),
+};
+#undef T
+
+int main(int argc, char **argv)
+{
+ char root[PATH_MAX];
+ int i, ret = EXIT_SUCCESS;
+
+ if (cg_find_unified_root(root, sizeof(root)))
+ ksft_exit_skip("cgroup v2 isn't mounted\n");
+
+ /*
+ * Check that memory controller is available:
+ * memory is listed in cgroup.controllers
+ */
+ if (cg_read_strstr(root, "cgroup.controllers", "memory"))
+ ksft_exit_skip("memory controller isn't available\n");
+
+ if (cg_read_strstr(root, "cgroup.subtree_control", "memory"))
+ if (cg_write(root, "cgroup.subtree_control", "+memory"))
+ ksft_exit_skip("Failed to set memory controller\n");
+
+ for (i = 0; i < ARRAY_SIZE(tests); i++) {
+ switch (tests[i].fn(root)) {
+ case KSFT_PASS:
+ ksft_test_result_pass("%s\n", tests[i].name);
+ break;
+ case KSFT_SKIP:
+ ksft_test_result_skip("%s\n", tests[i].name);
+ break;
+ default:
+ ret = EXIT_FAILURE;
+ ksft_test_result_fail("%s\n", tests[i].name);
+ break;
+ }
+ }
+
+ return ret;
+}
diff --git a/tools/testing/selftests/mincore/.gitignore b/tools/testing/selftests/mincore/.gitignore
new file mode 100644
index 000000000000..15c4dfc2df00
--- /dev/null
+++ b/tools/testing/selftests/mincore/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0+
+mincore_selftest
diff --git a/tools/testing/selftests/mincore/Makefile b/tools/testing/selftests/mincore/Makefile
new file mode 100644
index 000000000000..38c7db1e8926
--- /dev/null
+++ b/tools/testing/selftests/mincore/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+CFLAGS += -Wall
+
+TEST_GEN_PROGS := mincore_selftest
+include ../lib.mk
diff --git a/tools/testing/selftests/mincore/mincore_selftest.c b/tools/testing/selftests/mincore/mincore_selftest.c
new file mode 100644
index 000000000000..5a1e85ff5d32
--- /dev/null
+++ b/tools/testing/selftests/mincore/mincore_selftest.c
@@ -0,0 +1,361 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * kselftest suite for mincore().
+ *
+ * Copyright (C) 2020 Collabora, Ltd.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include "../kselftest.h"
+#include "../kselftest_harness.h"
+
+/* Default test file size: 4MB */
+#define MB (1UL << 20)
+#define FILE_SIZE (4 * MB)
+
+
+/*
+ * Tests the user interface. This test triggers most of the documented
+ * error conditions in mincore().
+ */
+TEST(basic_interface)
+{
+ int retval;
+ int page_size;
+ unsigned char vec[1];
+ char *addr;
+
+ page_size = sysconf(_SC_PAGESIZE);
+
+ /* Query a 0 byte sized range */
+ retval = mincore(0, 0, vec);
+ EXPECT_EQ(0, retval);
+
+ /* Addresses in the specified range are invalid or unmapped */
+ errno = 0;
+ retval = mincore(NULL, page_size, vec);
+ EXPECT_EQ(-1, retval);
+ EXPECT_EQ(ENOMEM, errno);
+
+ errno = 0;
+ addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(MAP_FAILED, addr) {
+ TH_LOG("mmap error: %s", strerror(errno));
+ }
+
+ /* <addr> argument is not page-aligned */
+ errno = 0;
+ retval = mincore(addr + 1, page_size, vec);
+ EXPECT_EQ(-1, retval);
+ EXPECT_EQ(EINVAL, errno);
+
+ /* <length> argument is too large */
+ errno = 0;
+ retval = mincore(addr, -1, vec);
+ EXPECT_EQ(-1, retval);
+ EXPECT_EQ(ENOMEM, errno);
+
+ /* <vec> argument points to an illegal address */
+ errno = 0;
+ retval = mincore(addr, page_size, NULL);
+ EXPECT_EQ(-1, retval);
+ EXPECT_EQ(EFAULT, errno);
+ munmap(addr, page_size);
+}
+
+
+/*
+ * Test mincore() behavior on a private anonymous page mapping.
+ * Check that the page is not loaded into memory right after the mapping
+ * but after accessing it (on-demand allocation).
+ * Then free the page and check that it's not memory-resident.
+ */
+TEST(check_anonymous_locked_pages)
+{
+ unsigned char vec[1];
+ char *addr;
+ int retval;
+ int page_size;
+
+ page_size = sysconf(_SC_PAGESIZE);
+
+ /* Map one page and check it's not memory-resident */
+ errno = 0;
+ addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(MAP_FAILED, addr) {
+ TH_LOG("mmap error: %s", strerror(errno));
+ }
+ retval = mincore(addr, page_size, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(0, vec[0]) {
+ TH_LOG("Page found in memory before use");
+ }
+
+ /* Touch the page and check again. It should now be in memory */
+ addr[0] = 1;
+ mlock(addr, page_size);
+ retval = mincore(addr, page_size, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(1, vec[0]) {
+ TH_LOG("Page not found in memory after use");
+ }
+
+ /*
+ * It shouldn't be memory-resident after unlocking it and
+ * marking it as unneeded.
+ */
+ munlock(addr, page_size);
+ madvise(addr, page_size, MADV_DONTNEED);
+ retval = mincore(addr, page_size, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(0, vec[0]) {
+ TH_LOG("Page in memory after being zapped");
+ }
+ munmap(addr, page_size);
+}
+
+
+/*
+ * Check mincore() behavior on huge pages.
+ * This test will be skipped if the mapping fails (ie. if there are no
+ * huge pages available).
+ *
+ * Make sure the system has at least one free huge page, check
+ * "HugePages_Free" in /proc/meminfo.
+ * Increment /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages if
+ * needed.
+ */
+TEST(check_huge_pages)
+{
+ unsigned char vec[1];
+ char *addr;
+ int retval;
+ int page_size;
+
+ page_size = sysconf(_SC_PAGESIZE);
+
+ errno = 0;
+ addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (addr == MAP_FAILED) {
+ if (errno == ENOMEM)
+ SKIP(return, "No huge pages available.");
+ else
+ TH_LOG("mmap error: %s", strerror(errno));
+ }
+ retval = mincore(addr, page_size, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(0, vec[0]) {
+ TH_LOG("Page found in memory before use");
+ }
+
+ addr[0] = 1;
+ mlock(addr, page_size);
+ retval = mincore(addr, page_size, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(1, vec[0]) {
+ TH_LOG("Page not found in memory after use");
+ }
+
+ munlock(addr, page_size);
+ munmap(addr, page_size);
+}
+
+
+/*
+ * Test mincore() behavior on a file-backed page.
+ * No pages should be loaded into memory right after the mapping. Then,
+ * accessing any address in the mapping range should load the page
+ * containing the address and a number of subsequent pages (readahead).
+ *
+ * The actual readahead settings depend on the test environment, so we
+ * can't make a lot of assumptions about that. This test covers the most
+ * general cases.
+ */
+TEST(check_file_mmap)
+{
+ unsigned char *vec;
+ int vec_size;
+ char *addr;
+ int retval;
+ int page_size;
+ int fd;
+ int i;
+ int ra_pages = 0;
+
+ page_size = sysconf(_SC_PAGESIZE);
+ vec_size = FILE_SIZE / page_size;
+ if (FILE_SIZE % page_size)
+ vec_size++;
+
+ vec = calloc(vec_size, sizeof(unsigned char));
+ ASSERT_NE(NULL, vec) {
+ TH_LOG("Can't allocate array");
+ }
+
+ errno = 0;
+ fd = open(".", O_TMPFILE | O_RDWR, 0600);
+ ASSERT_NE(-1, fd) {
+ TH_LOG("Can't create temporary file: %s",
+ strerror(errno));
+ }
+ errno = 0;
+ retval = fallocate(fd, 0, 0, FILE_SIZE);
+ ASSERT_EQ(0, retval) {
+ TH_LOG("Error allocating space for the temporary file: %s",
+ strerror(errno));
+ }
+
+ /*
+ * Map the whole file, the pages shouldn't be fetched yet.
+ */
+ errno = 0;
+ addr = mmap(NULL, FILE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ ASSERT_NE(MAP_FAILED, addr) {
+ TH_LOG("mmap error: %s", strerror(errno));
+ }
+ retval = mincore(addr, FILE_SIZE, vec);
+ ASSERT_EQ(0, retval);
+ for (i = 0; i < vec_size; i++) {
+ ASSERT_EQ(0, vec[i]) {
+ TH_LOG("Unexpected page in memory");
+ }
+ }
+
+ /*
+ * Touch a page in the middle of the mapping. We expect the next
+ * few pages (the readahead window) to be populated too.
+ */
+ addr[FILE_SIZE / 2] = 1;
+ retval = mincore(addr, FILE_SIZE, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(1, vec[FILE_SIZE / 2 / page_size]) {
+ TH_LOG("Page not found in memory after use");
+ }
+
+ i = FILE_SIZE / 2 / page_size + 1;
+ while (i < vec_size && vec[i]) {
+ ra_pages++;
+ i++;
+ }
+ EXPECT_GT(ra_pages, 0) {
+ TH_LOG("No read-ahead pages found in memory");
+ }
+
+ EXPECT_LT(i, vec_size) {
+ TH_LOG("Read-ahead pages reached the end of the file");
+ }
+ /*
+ * End of the readahead window. The rest of the pages shouldn't
+ * be in memory.
+ */
+ if (i < vec_size) {
+ while (i < vec_size && !vec[i])
+ i++;
+ EXPECT_EQ(vec_size, i) {
+ TH_LOG("Unexpected page in memory beyond readahead window");
+ }
+ }
+
+ munmap(addr, FILE_SIZE);
+ close(fd);
+ free(vec);
+}
+
+
+/*
+ * Test mincore() behavior on a page backed by a tmpfs file. This test
+ * performs the same steps as the previous one. However, we don't expect
+ * any readahead in this case.
+ */
+TEST(check_tmpfs_mmap)
+{
+ unsigned char *vec;
+ int vec_size;
+ char *addr;
+ int retval;
+ int page_size;
+ int fd;
+ int i;
+ int ra_pages = 0;
+
+ page_size = sysconf(_SC_PAGESIZE);
+ vec_size = FILE_SIZE / page_size;
+ if (FILE_SIZE % page_size)
+ vec_size++;
+
+ vec = calloc(vec_size, sizeof(unsigned char));
+ ASSERT_NE(NULL, vec) {
+ TH_LOG("Can't allocate array");
+ }
+
+ errno = 0;
+ fd = open("/dev/shm", O_TMPFILE | O_RDWR, 0600);
+ ASSERT_NE(-1, fd) {
+ TH_LOG("Can't create temporary file: %s",
+ strerror(errno));
+ }
+ errno = 0;
+ retval = fallocate(fd, 0, 0, FILE_SIZE);
+ ASSERT_EQ(0, retval) {
+ TH_LOG("Error allocating space for the temporary file: %s",
+ strerror(errno));
+ }
+
+ /*
+ * Map the whole file, the pages shouldn't be fetched yet.
+ */
+ errno = 0;
+ addr = mmap(NULL, FILE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ ASSERT_NE(MAP_FAILED, addr) {
+ TH_LOG("mmap error: %s", strerror(errno));
+ }
+ retval = mincore(addr, FILE_SIZE, vec);
+ ASSERT_EQ(0, retval);
+ for (i = 0; i < vec_size; i++) {
+ ASSERT_EQ(0, vec[i]) {
+ TH_LOG("Unexpected page in memory");
+ }
+ }
+
+ /*
+ * Touch a page in the middle of the mapping. We expect only
+ * that page to be fetched into memory.
+ */
+ addr[FILE_SIZE / 2] = 1;
+ retval = mincore(addr, FILE_SIZE, vec);
+ ASSERT_EQ(0, retval);
+ ASSERT_EQ(1, vec[FILE_SIZE / 2 / page_size]) {
+ TH_LOG("Page not found in memory after use");
+ }
+
+ i = FILE_SIZE / 2 / page_size + 1;
+ while (i < vec_size && vec[i]) {
+ ra_pages++;
+ i++;
+ }
+ ASSERT_EQ(ra_pages, 0) {
+ TH_LOG("Read-ahead pages found in memory");
+ }
+
+ munmap(addr, FILE_SIZE);
+ close(fd);
+ free(vec);
+}
+
+TEST_HARNESS_MAIN