Now that MADV_DONTNEED support for hugetlb is enabled, add corresponding tests. MADV_REMOVE has been enabled for some time, but no tests exist so add them as well. Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + tools/testing/selftests/vm/hugetlb-madvise.c | 410 +++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 12 + 4 files changed, 424 insertions(+) create mode 100644 tools/testing/selftests/vm/hugetlb-madvise.c diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index 3b5faec3c04f..d7507f3c7c76 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -3,6 +3,7 @@ hugepage-mmap hugepage-mremap hugepage-shm hugepage-vmemmap +hugetlb-madvise khugepaged map_hugetlb map_populate diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index 96714d2d49dc..5e43f072f5b7 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -28,6 +28,7 @@ LDLIBS = -lrt -lpthread TEST_GEN_FILES = compaction_test TEST_GEN_FILES += gup_test TEST_GEN_FILES += hmm-tests +TEST_GEN_FILES += hugetlb-madvise TEST_GEN_FILES += hugepage-mmap TEST_GEN_FILES += hugepage-mremap TEST_GEN_FILES += hugepage-shm diff --git a/tools/testing/selftests/vm/hugetlb-madvise.c b/tools/testing/selftests/vm/hugetlb-madvise.c new file mode 100644 index 000000000000..6c6af40f5747 --- /dev/null +++ b/tools/testing/selftests/vm/hugetlb-madvise.c @@ -0,0 +1,410 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * hugepage-madvise: + * + * Basic functional testing of madvise MADV_DONTNEED and MADV_REMOVE + * on hugetlb mappings. + * + * Before running this test, make sure the administrator has pre-allocated + * at least MIN_FREE_PAGES hugetlb pages and they are free. In addition, + * the test takes an argument that is the path to a file in a hugetlbfs + * filesystem. Therefore, a hugetlbfs filesystem must be mounted on some + * directory. + */ + +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#define __USE_GNU +#include <fcntl.h> + +#define USAGE "USAGE: %s <hugepagefile_name>\n" +#define MIN_FREE_PAGES 20 +#define NR_HUGE_PAGES 10 /* common number of pages to map/allocate */ + +#define validate_free_pages(exp_free) \ + do { \ + int fhp = get_free_hugepages(); \ + if (fhp != (exp_free)) { \ + printf("Unexpected number of free huge " \ + "pages line %d\n", __LINE__); \ + exit(1); \ + } \ + } while (0) + +unsigned long huge_page_size; +unsigned long base_page_size; + +/* + * default_huge_page_size copied from mlock2-tests.c + */ +unsigned long default_huge_page_size(void) +{ + unsigned long hps = 0; + char *line = NULL; + size_t linelen = 0; + FILE *f = fopen("/proc/meminfo", "r"); + + if (!f) + return 0; + while (getline(&line, &linelen, f) > 0) { + if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) { + hps <<= 10; + break; + } + } + + free(line); + fclose(f); + return hps; +} + +unsigned long get_free_hugepages(void) +{ + unsigned long fhp = 0; + char *line = NULL; + size_t linelen = 0; + FILE *f = fopen("/proc/meminfo", "r"); + + if (!f) + return fhp; + while (getline(&line, &linelen, f) > 0) { + if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1) + break; + } + + free(line); + fclose(f); + return fhp; +} + +void write_fault_pages(void *addr, unsigned long nr_pages) +{ + unsigned long i; + + for (i = 0; i < nr_pages; i++) + *((unsigned long *)(addr + (i * huge_page_size))) = i; +} + +void read_fault_pages(void *addr, unsigned long nr_pages) +{ + unsigned long i, tmp; + + for (i = 0; i < nr_pages; i++) + tmp += *((unsigned long *)(addr + (i * huge_page_size))); +} + +int main(int argc, char **argv) +{ + unsigned long free_hugepages; + void *addr, *addr2; + int fd; + int ret; + + if (argc != 2) { + printf(USAGE, argv[0]); + exit(1); + } + + huge_page_size = default_huge_page_size(); + if (!huge_page_size) { + printf("Unable to determine huge page size, exiting!\n"); + exit(1); + } + base_page_size = sysconf(_SC_PAGE_SIZE); + if (!huge_page_size) { + printf("Unable to determine base page size, exiting!\n"); + exit(1); + } + + free_hugepages = get_free_hugepages(); + if (free_hugepages < MIN_FREE_PAGES) { + printf("Not enough free huge pages to test, exiting!\n"); + exit(1); + } + + fd = open(argv[1], O_CREAT | O_RDWR, 0755); + if (fd < 0) { + perror("Open failed"); + exit(1); + } + + /* + * Test validity of MADV_DONTNEED addr and length arguments. mmap + * size is NR_HUGE_PAGES + 2. One page at the beginning and end of + * the mapping will be unmapped so we KNOW there is nothing mapped + * there. + */ + addr = mmap(NULL, (NR_HUGE_PAGES + 2) * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, + -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + if (munmap(addr, huge_page_size) || + munmap(addr + (NR_HUGE_PAGES + 1) * huge_page_size, + huge_page_size)) { + perror("munmap"); + exit(1); + } + addr = addr + huge_page_size; + + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* addr before mapping should fail */ + ret = madvise(addr - base_page_size, NR_HUGE_PAGES * huge_page_size, + MADV_DONTNEED); + if (!ret) { + printf("Unexpected success of madvise call with invalid addr line %d\n", + __LINE__); + exit(1); + } + + /* addr + length after mapping should fail */ + ret = madvise(addr, (NR_HUGE_PAGES * huge_page_size) + base_page_size, + MADV_DONTNEED); + if (!ret) { + printf("Unexpected success of madvise call with invalid length line %d\n", + __LINE__); + exit(1); + } + + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + + /* + * Test alignment of MADV_DONTNEED addr and length arguments + */ + addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, + -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* addr is not huge page size aligned and should fail */ + ret = madvise(addr + base_page_size, + NR_HUGE_PAGES * huge_page_size - base_page_size, + MADV_DONTNEED); + if (!ret) { + printf("Unexpected success of madvise call with unaligned start address %d\n", + __LINE__); + exit(1); + } + + /* addr + length should be aligned up to huge page size */ + if (madvise(addr, + ((NR_HUGE_PAGES - 1) * huge_page_size) + base_page_size, + MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + + /* should free all pages in mapping */ + validate_free_pages(free_hugepages); + + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + + /* + * Test MADV_DONTNEED on anonymous private mapping + */ + addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, + -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + + /* should free all pages in mapping */ + validate_free_pages(free_hugepages); + + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + + /* + * Test MADV_DONTNEED on private mapping of hugetlb file + */ + if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) { + perror("fallocate"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE, fd, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + /* read should not consume any pages */ + read_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* madvise should not free any pages */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* writes should allocate private pages */ + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES)); + + /* madvise should free private pages */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* writes should allocate private pages */ + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES)); + + /* + * The fallocate below certainly should free the pages associated + * with the file. However, pages in the private mapping are also + * freed. This is not the 'correct' behavior, but is expected + * because this is how it has worked since the initial hugetlb + * implementation. + */ + if (fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + 0, NR_HUGE_PAGES * huge_page_size)) { + perror("fallocate"); + exit(1); + } + validate_free_pages(free_hugepages); + + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + + /* + * Test MADV_DONTNEED on shared mapping of hugetlb file + */ + if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) { + perror("fallocate"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + /* write should not consume any pages */ + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* madvise should not free any pages */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* + * Test MADV_REMOVE on shared mapping of hugetlb file + * + * madvise is same as hole punch and should free all pages. + */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_REMOVE)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages); + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + + /* + * Test MADV_REMOVE on shared and private mapping of hugetlb file + */ + if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) { + perror("fallocate"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + /* shared write should not consume any additional pages */ + write_fault_pages(addr, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + addr2 = mmap(NULL, NR_HUGE_PAGES * huge_page_size, + PROT_READ | PROT_WRITE, + MAP_PRIVATE, fd, 0); + if (addr2 == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + /* private read should not consume any pages */ + read_fault_pages(addr2, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* private write should consume additional pages */ + write_fault_pages(addr2, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES)); + + /* madvise of shared mapping should not free any pages */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES)); + + /* madvise of private mapping should free private pages */ + if (madvise(addr2, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages - NR_HUGE_PAGES); + + /* private write should consume additional pages again */ + write_fault_pages(addr2, NR_HUGE_PAGES); + validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES)); + + /* + * madvise should free both file and private pages although this is + * not correct. private pages should not be freed, but this is + * expected. See comment associated with FALLOC_FL_PUNCH_HOLE call. + */ + if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_REMOVE)) { + perror("madvise"); + exit(1); + } + validate_free_pages(free_hugepages); + + (void)munmap(addr, NR_HUGE_PAGES * huge_page_size); + (void)munmap(addr2, NR_HUGE_PAGES * huge_page_size); + + close(fd); + unlink(argv[1]); + return 0; +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index e10d50e0b8e8..1948098f431d 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -131,6 +131,18 @@ else echo "[PASS]" fi +echo "-----------------------" +echo "running hugetlb-madvise" +echo "-----------------------" +./hugetlb-madvise $mnt/madvise-test +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi +rm -f $mnt/madvise-test + echo "NOTE: The above hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" echo " hugetlb regression testing." -- 2.34.1