On 2024/6/12 5:55, Jiaqi Yan wrote: > Add regression and new tests when hugepage has correctable memory > errors, and how userspace wants to deal with it: > * if enable_soft_offline=0, mapped hugepage is soft offlined > * if enable_soft_offline=1, mapped hugepage is intact This shoule be something like below ? if enable_soft_offline=0, mapped hugepage is intact if enable_soft_offline=1, mapped hugepage is soft offlined > > Free hugepages case is not explicitly covered by the tests. > > Hugepage having corrected memory errors is emulated with > MADV_SOFT_OFFLINE. > > Signed-off-by: Jiaqi Yan <jiaqiyan@xxxxxxxxxx> > --- > tools/testing/selftests/mm/.gitignore | 1 + > tools/testing/selftests/mm/Makefile | 1 + > .../selftests/mm/hugetlb-soft-offline.c | 258 ++++++++++++++++++ > tools/testing/selftests/mm/run_vmtests.sh | 4 + > 4 files changed, 264 insertions(+) > create mode 100644 tools/testing/selftests/mm/hugetlb-soft-offline.c > > diff --git a/tools/testing/selftests/mm/.gitignore b/tools/testing/selftests/mm/.gitignore > index 0b9ab987601c..064e7b125643 100644 > --- a/tools/testing/selftests/mm/.gitignore > +++ b/tools/testing/selftests/mm/.gitignore > @@ -6,6 +6,7 @@ hugepage-shm > hugepage-vmemmap > hugetlb-madvise > hugetlb-read-hwpoison > +hugetlb-soft-offline > khugepaged > map_hugetlb > map_populate > diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile > index 3b49bc3d0a3b..d166067d75ef 100644 > --- a/tools/testing/selftests/mm/Makefile > +++ b/tools/testing/selftests/mm/Makefile > @@ -42,6 +42,7 @@ TEST_GEN_FILES += gup_test > TEST_GEN_FILES += hmm-tests > TEST_GEN_FILES += hugetlb-madvise > TEST_GEN_FILES += hugetlb-read-hwpoison > +TEST_GEN_FILES += hugetlb-soft-offline > TEST_GEN_FILES += hugepage-mmap > TEST_GEN_FILES += hugepage-mremap > TEST_GEN_FILES += hugepage-shm > diff --git a/tools/testing/selftests/mm/hugetlb-soft-offline.c b/tools/testing/selftests/mm/hugetlb-soft-offline.c > new file mode 100644 > index 000000000000..d37d68a433e7 > --- /dev/null > +++ b/tools/testing/selftests/mm/hugetlb-soft-offline.c > @@ -0,0 +1,258 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Test soft offline behavior for HugeTLB pages: > + * - if enable_soft_offline = 0, hugepages should stay intact and soft > + * offlining failed with EINVAL. > + * - if enable_soft_offline = 1, a hugepage should be dissolved and > + * nr_hugepages/free_hugepages should be reduced by 1. > + * > + * Before running, make sure more than 2 hugepages of default_hugepagesz > + * are allocated. For example, if /proc/meminfo/Hugepagesize is 2048kB: > + * echo 8 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages > + */ > + > +#define _GNU_SOURCE > +#include <errno.h> > +#include <stdlib.h> > +#include <stdio.h> > +#include <string.h> > +#include <unistd.h> > + > +#include <linux/magic.h> > +#include <linux/memfd.h> > +#include <sys/mman.h> > +#include <sys/statfs.h> > +#include <sys/types.h> > + > +#ifndef MADV_SOFT_OFFLINE > +#define MADV_SOFT_OFFLINE 101 > +#endif > + > +#define PREFIX " ... " > +#define EPREFIX " !!! " > + > +enum test_status { > + TEST_PASS = 0, > + TEST_FAILED = 1, > + // From ${ksft_skip} in run_vmtests.sh. > + TEST_SKIPPED = 4, > +}; > + > +static enum test_status do_soft_offline(int fd, size_t len, int expect_ret) > +{ > + char *filemap = NULL; > + char *hwp_addr = NULL; > + const unsigned long pagesize = getpagesize(); > + int ret = 0; > + enum test_status status = TEST_SKIPPED; > + > + if (ftruncate(fd, len) < 0) { > + perror(EPREFIX "ftruncate to len failed"); > + return status; > + } > + > + filemap = mmap(NULL, len, PROT_READ | PROT_WRITE, > + MAP_SHARED | MAP_POPULATE, fd, 0); > + if (filemap == MAP_FAILED) { > + perror(EPREFIX "mmap failed"); > + goto untruncate; > + } > + > + memset(filemap, 0xab, len); > + printf(PREFIX "Allocated %#lx bytes of hugetlb pages\n", len); > + > + hwp_addr = filemap + len / 2; > + ret = madvise(hwp_addr, pagesize, MADV_SOFT_OFFLINE); > + printf(PREFIX "MADV_SOFT_OFFLINE %p ret=%d, errno=%d\n", > + hwp_addr, ret, errno); > + if (ret != 0) > + perror(EPREFIX "madvise failed"); > + > + if (errno == expect_ret) > + status = TEST_PASS; > + else { > + printf(EPREFIX "MADV_SOFT_OFFLINE should ret %d\n", expect_ret); > + status = TEST_FAILED; > + } > + > + munmap(filemap, len); > +untruncate: > + if (ftruncate(fd, 0) < 0) > + perror(EPREFIX "ftruncate back to 0 failed"); > + > + return status; > +} > + > +static int set_enable_soft_offline(int value) > +{ > + char cmd[256] = {0}; > + FILE *cmdfile = NULL; > + > + if (value != 0 && value != 1) > + return -EINVAL; > + > + sprintf(cmd, "echo %d > /proc/sys/vm/enable_soft_offline", value); > + cmdfile = popen(cmd, "r"); > + > + if (cmdfile == NULL) > + perror(EPREFIX "failed to set enable_soft_offline"); If fails to set enable_soft_offline, should we return errno here? > + else > + printf(PREFIX "enable_soft_offline => %d\n", value); > + > + pclose(cmdfile); > + return 0; > +} > + > +static int read_nr_hugepages(unsigned long hugepage_size, > + unsigned long *nr_hugepages) > +{ > + char buffer[256] = {0}; > + char cmd[256] = {0}; > + > + sprintf(cmd, "cat /sys/kernel/mm/hugepages/hugepages-%ldkB/nr_hugepages", > + hugepage_size); > + FILE *cmdfile = popen(cmd, "r"); Check cmdfile against NULL? > + > + if (!fgets(buffer, sizeof(buffer), cmdfile)) { > + perror(EPREFIX "failed to read nr_hugepages"); > + pclose(cmdfile); > + return -1; > + } > + > + *nr_hugepages = atoll(buffer); > + pclose(cmdfile); > + return 0; > +} > + > +static int create_hugetlbfs_file(struct statfs *file_stat) > +{ > + int fd; > + > + fd = memfd_create("hugetlb_tmp", MFD_HUGETLB); > + if (fd < 0) { > + perror(EPREFIX "could not open hugetlbfs file"); > + return -1; > + } > + > + memset(file_stat, 0, sizeof(*file_stat)); > + if (fstatfs(fd, file_stat)) { > + perror(EPREFIX "fstatfs failed"); > + goto close; > + } > + if (file_stat->f_type != HUGETLBFS_MAGIC) { > + printf(EPREFIX "not hugetlbfs file\n"); > + goto close; > + } > + > + return fd; > +close: > + close(fd); > + return -1; > +} > + > +static enum test_status test_soft_offline(void) > +{ > + int fd; > + struct statfs file_stat; > + unsigned long hugepagesize_kb = 0; > + unsigned long nr_hugepages_before = 0; > + unsigned long nr_hugepages_after = 0; > + enum test_status status = TEST_SKIPPED; > + > + printf("Test Soft Offline When softoffline_corrected_errors=1\n"); > + > + fd = create_hugetlbfs_file(&file_stat); > + if (fd < 0) { > + printf(EPREFIX "Failed to create hugetlbfs file\n"); > + return status; > + } > + > + hugepagesize_kb = file_stat.f_bsize / 1024; > + printf(PREFIX "Hugepagesize is %ldkB\n", hugepagesize_kb); > + > + if (set_enable_soft_offline(1)) > + return TEST_FAILED; > + > + if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_before) != 0) > + return TEST_FAILED; > + > + printf(PREFIX "Before MADV_SOFT_OFFLINE nr_hugepages=%ld\n", > + nr_hugepages_before); > + > + status = do_soft_offline(fd, 2 * file_stat.f_bsize, /*expect_ret=*/0); > + > + if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_after) != 0) > + return TEST_FAILED; > + > + printf(PREFIX "After MADV_SOFT_OFFLINE nr_hugepages=%ld\n", > + nr_hugepages_after); > + > + if (nr_hugepages_before != nr_hugepages_after + 1) { > + printf(EPREFIX "MADV_SOFT_OFFLINE should reduced 1 hugepage\n"); > + return TEST_FAILED; > + } > + > + return status; > +} > + > +static enum test_status test_disable_soft_offline(void) > +{ > + int fd; > + struct statfs file_stat; > + unsigned long hugepagesize_kb = 0; > + unsigned long nr_hugepages_before = 0; > + unsigned long nr_hugepages_after = 0; > + enum test_status status = TEST_SKIPPED; > + > + printf("Test Soft Offline When softoffline_corrected_errors=0\n"); > + > + fd = create_hugetlbfs_file(&file_stat); > + if (fd < 0) { > + printf(EPREFIX "Failed to create hugetlbfs file\n"); > + return status; > + } > + > + hugepagesize_kb = file_stat.f_bsize / 1024; > + printf(PREFIX "Hugepagesize is %ldkB\n", hugepagesize_kb); > + > + if (set_enable_soft_offline(0)) > + return TEST_FAILED; > + > + if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_before) != 0) > + return TEST_FAILED; > + > + printf(PREFIX "Before MADV_SOFT_OFFLINE nr_hugepages=%ld\n", > + nr_hugepages_before); > + > + status = do_soft_offline(fd, 2 * file_stat.f_bsize, /*expect_ret=*/EINVAL); > + > + if (read_nr_hugepages(hugepagesize_kb, &nr_hugepages_after) != 0) > + return TEST_FAILED; > + > + printf(PREFIX "After MADV_SOFT_OFFLINE nr_hugepages=%ld\n", > + nr_hugepages_after); > + > + if (nr_hugepages_before != nr_hugepages_after) { > + printf(EPREFIX "MADV_SOFT_OFFLINE reduced %lu hugepages\n", > + nr_hugepages_before - nr_hugepages_after); > + return TEST_FAILED; > + } > + > + return status; > +} test_disable_soft_offline is almost same with test_soft_offline. Shall we extract the common pattern? Thanks. .