From: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Subject: userfaultfd: hugetlbfs: add userfaultfd_hugetlb test Test userfaultfd hugetlb functionality by using the existing testing method (in userfaultfd.c). Instead of an anonymous memeory, a hugetlbfs file is mmap'ed private. In this way fallocate hole punch can be used to release pages. This is because madvise(MADV_DONTNEED) is not supported for huge pages. Use the same file, but create wrappers for allocating ranges and releasing pages. Compile userfaultfd.c with HUGETLB_TEST defined to produce an executable to test userfaultfd hugetlb functionality. Link: http://lkml.kernel.org/r/20161216144821.5183-23-aarcange@xxxxxxxxxx Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: "Dr. David Alan Gilbert" <dgilbert@xxxxxxxxxx> Cc: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx> Cc: Michael Rapoport <RAPOPORT@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/Makefile | 4 tools/testing/selftests/vm/run_vmtests | 13 + tools/testing/selftests/vm/userfaultfd.c | 161 ++++++++++++++++++--- 3 files changed, 161 insertions(+), 17 deletions(-) diff -puN tools/testing/selftests/vm/Makefile~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test tools/testing/selftests/vm/Makefile --- a/tools/testing/selftests/vm/Makefile~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test +++ a/tools/testing/selftests/vm/Makefile @@ -10,6 +10,7 @@ BINARIES += on-fault-limit BINARIES += thuge-gen BINARIES += transhuge-stress BINARIES += userfaultfd +BINARIES += userfaultfd_hugetlb BINARIES += mlock-random-test all: $(BINARIES) @@ -18,6 +19,9 @@ all: $(BINARIES) userfaultfd: userfaultfd.c ../../../../usr/include/linux/kernel.h $(CC) $(CFLAGS) -O2 -o $@ $< -lpthread +userfaultfd_hugetlb: userfaultfd.c ../../../../usr/include/linux/kernel.h + $(CC) $(CFLAGS) -DHUGETLB_TEST -O2 -o $@ $< -lpthread + mlock-random-test: mlock-random-test.c $(CC) $(CFLAGS) -o $@ $< -lcap diff -puN tools/testing/selftests/vm/run_vmtests~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test tools/testing/selftests/vm/run_vmtests --- a/tools/testing/selftests/vm/run_vmtests~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test +++ a/tools/testing/selftests/vm/run_vmtests @@ -103,6 +103,19 @@ else echo "[PASS]" fi +echo "----------------------------" +echo "running userfaultfd_hugetlb" +echo "----------------------------" +# 258MB total huge pages == 128MB src and 128MB dst +./userfaultfd_hugetlb 128 32 $mnt/ufd_test_file +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi +rm -f $mnt/ufd_test_file + #cleanup umount $mnt rm -rf $mnt diff -puN tools/testing/selftests/vm/userfaultfd.c~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test tools/testing/selftests/vm/userfaultfd.c --- a/tools/testing/selftests/vm/userfaultfd.c~userfaultfd-hugetlbfs-add-userfaultfd_hugetlb-test +++ a/tools/testing/selftests/vm/userfaultfd.c @@ -76,6 +76,10 @@ static unsigned long nr_cpus, nr_pages, #define BOUNCE_POLL (1<<3) static int bounces; +#ifdef HUGETLB_TEST +static int huge_fd; +static char *huge_fd_off0; +#endif static unsigned long long *count_verify; static int uffd, finished, *pipefd; static char *area_src, *area_dst; @@ -97,6 +101,69 @@ pthread_attr_t attr; ~(unsigned long)(sizeof(unsigned long long) \ - 1))) +#ifndef HUGETLB_TEST + +#define EXPECTED_IOCTLS ((1 << _UFFDIO_WAKE) | \ + (1 << _UFFDIO_COPY) | \ + (1 << _UFFDIO_ZEROPAGE)) + +static int release_pages(char *rel_area) +{ + int ret = 0; + + if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED)) { + perror("madvise"); + ret = 1; + } + + return ret; +} + +static void allocate_area(void **alloc_area) +{ + if (posix_memalign(alloc_area, page_size, nr_pages * page_size)) { + fprintf(stderr, "out of memory\n"); + *alloc_area = NULL; + } +} + +#else /* HUGETLB_TEST */ + +#define EXPECTED_IOCTLS UFFD_API_RANGE_IOCTLS_HPAGE + +static int release_pages(char *rel_area) +{ + int ret = 0; + + if (fallocate(huge_fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + rel_area == huge_fd_off0 ? 0 : + nr_pages * page_size, + nr_pages * page_size)) { + perror("fallocate"); + ret = 1; + } + + return ret; +} + + +static void allocate_area(void **alloc_area) +{ + *alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_HUGETLB, huge_fd, + *alloc_area == area_src ? 0 : + nr_pages * page_size); + if (*alloc_area == MAP_FAILED) { + fprintf(stderr, "mmap of hugetlbfs file failed\n"); + *alloc_area = NULL; + } + + if (*alloc_area == area_src) + huge_fd_off0 = *alloc_area; +} + +#endif /* HUGETLB_TEST */ + static int my_bcmp(char *str1, char *str2, size_t n) { unsigned long i; @@ -384,10 +451,8 @@ static int stress(unsigned long *userfau * UFFDIO_COPY without writing zero pages into area_dst * because the background threads already completed). */ - if (madvise(area_src, nr_pages * page_size, MADV_DONTNEED)) { - perror("madvise"); + if (release_pages(area_src)) return 1; - } for (cpu = 0; cpu < nr_cpus; cpu++) { char c; @@ -425,16 +490,12 @@ static int userfaultfd_stress(void) int uffd_flags, err; unsigned long userfaults[nr_cpus]; - if (posix_memalign(&area, page_size, nr_pages * page_size)) { - fprintf(stderr, "out of memory\n"); + allocate_area((void **)&area_src); + if (!area_src) return 1; - } - area_src = area; - if (posix_memalign(&area, page_size, nr_pages * page_size)) { - fprintf(stderr, "out of memory\n"); + allocate_area((void **)&area_dst); + if (!area_dst) return 1; - } - area_dst = area; uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); if (uffd < 0) { @@ -528,9 +589,7 @@ static int userfaultfd_stress(void) fprintf(stderr, "register failure\n"); return 1; } - expected_ioctls = (1 << _UFFDIO_WAKE) | - (1 << _UFFDIO_COPY) | - (1 << _UFFDIO_ZEROPAGE); + expected_ioctls = EXPECTED_IOCTLS; if ((uffdio_register.ioctls & expected_ioctls) != expected_ioctls) { fprintf(stderr, @@ -562,10 +621,8 @@ static int userfaultfd_stress(void) * MADV_DONTNEED only after the UFFDIO_REGISTER, so it's * required to MADV_DONTNEED here. */ - if (madvise(area_dst, nr_pages * page_size, MADV_DONTNEED)) { - perror("madvise 2"); + if (release_pages(area_dst)) return 1; - } /* bounce pass */ if (stress(userfaults)) @@ -606,6 +663,8 @@ static int userfaultfd_stress(void) return err; } +#ifndef HUGETLB_TEST + int main(int argc, char **argv) { if (argc < 3) @@ -632,6 +691,74 @@ int main(int argc, char **argv) return userfaultfd_stress(); } +#else /* HUGETLB_TEST */ + +/* + * 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; +} + +int main(int argc, char **argv) +{ + if (argc < 4) + fprintf(stderr, "Usage: <MiB> <bounces> <hugetlbfs_file>\n"), + exit(1); + nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); + page_size = default_huge_page_size(); + if (!page_size) + fprintf(stderr, "Unable to determine huge page size\n"), + exit(2); + if ((unsigned long) area_count(NULL, 0) + sizeof(unsigned long long) * 2 + > page_size) + fprintf(stderr, "Impossible to run this test\n"), exit(2); + nr_pages_per_cpu = atol(argv[1]) * 1024*1024 / page_size / + nr_cpus; + if (!nr_pages_per_cpu) { + fprintf(stderr, "invalid MiB\n"); + fprintf(stderr, "Usage: <MiB> <bounces>\n"), exit(1); + } + bounces = atoi(argv[2]); + if (bounces <= 0) { + fprintf(stderr, "invalid bounces\n"); + fprintf(stderr, "Usage: <MiB> <bounces>\n"), exit(1); + } + nr_pages = nr_pages_per_cpu * nr_cpus; + huge_fd = open(argv[3], O_CREAT | O_RDWR, 0755); + if (huge_fd < 0) { + fprintf(stderr, "Open of %s failed", argv[3]); + perror("open"); + exit(1); + } + if (ftruncate(huge_fd, 0)) { + fprintf(stderr, "ftruncate %s to size 0 failed", argv[3]); + perror("ftruncate"); + exit(1); + } + printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n", + nr_pages, nr_pages_per_cpu); + return userfaultfd_stress(); +} + +#endif #else /* __NR_userfaultfd */ #warning "missing __NR_userfaultfd definition" _ -- 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
