aboutsummaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/vm/compaction_test.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-29 09:11:10 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-29 09:11:10 -0700
commitd93a74a91b847b8098ebae749891c6f4fe563da0 (patch)
treefb1ef1b9f496a3ad492ce076ae8f41d716964c63 /tools/testing/selftests/vm/compaction_test.c
parentMerge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu (diff)
parentselftests: add quicktest support (diff)
downloadlinux-dev-d93a74a91b847b8098ebae749891c6f4fe563da0.tar.xz
linux-dev-d93a74a91b847b8098ebae749891c6f4fe563da0.zip
Merge tag 'linux-kselftest-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest update from Shuah Khan: "This update adds two new test suites: futex and seccomp. In addition, it includes fixes for bugs in timers, other tests, and compile framework. It introduces new quicktest feature to enable users to choose to run tests that complete in a short time" * tag 'linux-kselftest-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests: add quicktest support selftests: add seccomp suite selftest, x86: fix incorrect comment tools selftests: Fix 'clean' target with make 3.81 selftests/futex: Add .gitignore kselftest: Add exit code defines selftests: Add futex tests to the top-level Makefile selftests/futex: Increment ksft pass and fail counters selftests/futex: Update Makefile to use lib.mk selftests: Add futex functional tests kselftests: timers: Check _ALARM clockids are supported before suspending kselftests: timers: Ease alarmtimer-suspend unreasonable latency value kselftests: timers: Increase delay between suspends in alarmtimer-suspend selftests/exec: do not install subdir as it is already created selftests/ftrace: install test.d selftests: copy TEST_DIRS to INSTALL_PATH Test compaction of mlocked memory selftests/mount: output WARN messages when mount test skipped selftests/timers: Make git ignore all binaries in timers test suite
Diffstat (limited to 'tools/testing/selftests/vm/compaction_test.c')
-rw-r--r--tools/testing/selftests/vm/compaction_test.c225
1 files changed, 225 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/compaction_test.c b/tools/testing/selftests/vm/compaction_test.c
new file mode 100644
index 000000000000..932ff577ffc0
--- /dev/null
+++ b/tools/testing/selftests/vm/compaction_test.c
@@ -0,0 +1,225 @@
+/*
+ *
+ * A test for the patch "Allow compaction of unevictable pages".
+ * With this patch we should be able to allocate at least 1/4
+ * of RAM in huge pages. Without the patch much less is
+ * allocated.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+
+#define MAP_SIZE 1048576
+
+struct map_list {
+ void *map;
+ struct map_list *next;
+};
+
+int read_memory_info(unsigned long *memfree, unsigned long *hugepagesize)
+{
+ char buffer[256] = {0};
+ char *cmd = "cat /proc/meminfo | grep -i memfree | grep -o '[0-9]*'";
+ FILE *cmdfile = popen(cmd, "r");
+
+ if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
+ perror("Failed to read meminfo\n");
+ return -1;
+ }
+
+ pclose(cmdfile);
+
+ *memfree = atoll(buffer);
+ cmd = "cat /proc/meminfo | grep -i hugepagesize | grep -o '[0-9]*'";
+ cmdfile = popen(cmd, "r");
+
+ if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
+ perror("Failed to read meminfo\n");
+ return -1;
+ }
+
+ pclose(cmdfile);
+ *hugepagesize = atoll(buffer);
+
+ return 0;
+}
+
+int prereq(void)
+{
+ char allowed;
+ int fd;
+
+ fd = open("/proc/sys/vm/compact_unevictable_allowed",
+ O_RDONLY | O_NONBLOCK);
+ if (fd < 0) {
+ perror("Failed to open\n"
+ "/proc/sys/vm/compact_unevictable_allowed\n");
+ return -1;
+ }
+
+ if (read(fd, &allowed, sizeof(char)) != sizeof(char)) {
+ perror("Failed to read from\n"
+ "/proc/sys/vm/compact_unevictable_allowed\n");
+ close(fd);
+ return -1;
+ }
+
+ close(fd);
+ if (allowed == '1')
+ return 0;
+
+ return -1;
+}
+
+int check_compaction(unsigned long mem_free, unsigned int hugepage_size)
+{
+ int fd;
+ int compaction_index = 0;
+ char initial_nr_hugepages[10] = {0};
+ char nr_hugepages[10] = {0};
+
+ /* We want to test with 80% of available memory. Else, OOM killer comes
+ in to play */
+ mem_free = mem_free * 0.8;
+
+ fd = open("/proc/sys/vm/nr_hugepages", O_RDWR | O_NONBLOCK);
+ if (fd < 0) {
+ perror("Failed to open /proc/sys/vm/nr_hugepages");
+ return -1;
+ }
+
+ if (read(fd, initial_nr_hugepages, sizeof(initial_nr_hugepages)) <= 0) {
+ perror("Failed to read from /proc/sys/vm/nr_hugepages");
+ goto close_fd;
+ }
+
+ /* Start with the initial condition of 0 huge pages*/
+ if (write(fd, "0", sizeof(char)) != sizeof(char)) {
+ perror("Failed to write to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ lseek(fd, 0, SEEK_SET);
+
+ /* Request a large number of huge pages. The Kernel will allocate
+ as much as it can */
+ if (write(fd, "100000", (6*sizeof(char))) != (6*sizeof(char))) {
+ perror("Failed to write to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ lseek(fd, 0, SEEK_SET);
+
+ if (read(fd, nr_hugepages, sizeof(nr_hugepages)) <= 0) {
+ perror("Failed to read from /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ /* We should have been able to request at least 1/3 rd of the memory in
+ huge pages */
+ compaction_index = mem_free/(atoi(nr_hugepages) * hugepage_size);
+
+ if (compaction_index > 3) {
+ printf("No of huge pages allocated = %d\n",
+ (atoi(nr_hugepages)));
+ fprintf(stderr, "ERROR: Less that 1/%d of memory is available\n"
+ "as huge pages\n", compaction_index);
+ goto close_fd;
+ }
+
+ printf("No of huge pages allocated = %d\n",
+ (atoi(nr_hugepages)));
+
+ if (write(fd, initial_nr_hugepages, sizeof(initial_nr_hugepages))
+ != strlen(initial_nr_hugepages)) {
+ perror("Failed to write to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ close(fd);
+ return 0;
+
+ close_fd:
+ close(fd);
+ printf("Not OK. Compaction test failed.");
+ return -1;
+}
+
+
+int main(int argc, char **argv)
+{
+ struct rlimit lim;
+ struct map_list *list, *entry;
+ size_t page_size, i;
+ void *map = NULL;
+ unsigned long mem_free = 0;
+ unsigned long hugepage_size = 0;
+ unsigned long mem_fragmentable = 0;
+
+ if (prereq() != 0) {
+ printf("Either the sysctl compact_unevictable_allowed is not\n"
+ "set to 1 or couldn't read the proc file.\n"
+ "Skipping the test\n");
+ return 0;
+ }
+
+ lim.rlim_cur = RLIM_INFINITY;
+ lim.rlim_max = RLIM_INFINITY;
+ if (setrlimit(RLIMIT_MEMLOCK, &lim)) {
+ perror("Failed to set rlimit:\n");
+ return -1;
+ }
+
+ page_size = getpagesize();
+
+ list = NULL;
+
+ if (read_memory_info(&mem_free, &hugepage_size) != 0) {
+ printf("ERROR: Cannot read meminfo\n");
+ return -1;
+ }
+
+ mem_fragmentable = mem_free * 0.8 / 1024;
+
+ while (mem_fragmentable > 0) {
+ map = mmap(NULL, MAP_SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE | MAP_LOCKED, -1, 0);
+ if (map == MAP_FAILED)
+ break;
+
+ entry = malloc(sizeof(struct map_list));
+ if (!entry) {
+ munmap(map, MAP_SIZE);
+ break;
+ }
+ entry->map = map;
+ entry->next = list;
+ list = entry;
+
+ /* Write something (in this case the address of the map) to
+ * ensure that KSM can't merge the mapped pages
+ */
+ for (i = 0; i < MAP_SIZE; i += page_size)
+ *(unsigned long *)(map + i) = (unsigned long)map + i;
+
+ mem_fragmentable--;
+ }
+
+ for (entry = list; entry != NULL; entry = entry->next) {
+ munmap(entry->map, MAP_SIZE);
+ if (!entry->next)
+ break;
+ entry = entry->next;
+ }
+
+ if (check_compaction(mem_free, hugepage_size) == 0)
+ return 0;
+
+ return -1;
+}