![Mike Rapoport](/assets/img/avatar_default.png)
Currently, selftest for userfaultfd is compiled three times: for anonymous, shared and hugetlb memory. Let's combine all the cases into a single executable which will have a command line option for selection of the test type. Link: http://lkml.kernel.org/r/1490869741-5913-1-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1059 lines
27 KiB
C
1059 lines
27 KiB
C
/*
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* Stress userfaultfd syscall.
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*
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* Copyright (C) 2015 Red Hat, Inc.
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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* This test allocates two virtual areas and bounces the physical
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* memory across the two virtual areas (from area_src to area_dst)
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* using userfaultfd.
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*
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* There are three threads running per CPU:
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*
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* 1) one per-CPU thread takes a per-page pthread_mutex in a random
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* page of the area_dst (while the physical page may still be in
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* area_src), and increments a per-page counter in the same page,
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* and checks its value against a verification region.
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*
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* 2) another per-CPU thread handles the userfaults generated by
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* thread 1 above. userfaultfd blocking reads or poll() modes are
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* exercised interleaved.
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*
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* 3) one last per-CPU thread transfers the memory in the background
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* at maximum bandwidth (if not already transferred by thread
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* 2). Each cpu thread takes cares of transferring a portion of the
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* area.
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*
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* When all threads of type 3 completed the transfer, one bounce is
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* complete. area_src and area_dst are then swapped. All threads are
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* respawned and so the bounce is immediately restarted in the
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* opposite direction.
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*
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* per-CPU threads 1 by triggering userfaults inside
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* pthread_mutex_lock will also verify the atomicity of the memory
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* transfer (UFFDIO_COPY).
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*
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* The program takes two parameters: the amounts of physical memory in
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* megabytes (MiB) of the area and the number of bounces to execute.
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*
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* # 100MiB 99999 bounces
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* ./userfaultfd 100 99999
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*
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* # 1GiB 99 bounces
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* ./userfaultfd 1000 99
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*
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* # 10MiB-~6GiB 999 bounces, continue forever unless an error triggers
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* while ./userfaultfd $[RANDOM % 6000 + 10] 999; do true; done
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*/
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#define _GNU_SOURCE
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#include <stdio.h>
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#include <errno.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <time.h>
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#include <signal.h>
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#include <poll.h>
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#include <string.h>
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#include <sys/mman.h>
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#include <sys/syscall.h>
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#include <sys/ioctl.h>
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#include <sys/wait.h>
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#include <pthread.h>
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#include <linux/userfaultfd.h>
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#ifdef __NR_userfaultfd
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static unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size;
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#define BOUNCE_RANDOM (1<<0)
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#define BOUNCE_RACINGFAULTS (1<<1)
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#define BOUNCE_VERIFY (1<<2)
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#define BOUNCE_POLL (1<<3)
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static int bounces;
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#define TEST_ANON 1
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#define TEST_HUGETLB 2
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#define TEST_SHMEM 3
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static int test_type;
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static int huge_fd;
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static char *huge_fd_off0;
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static unsigned long long *count_verify;
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static int uffd, uffd_flags, finished, *pipefd;
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static char *area_src, *area_dst;
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static char *zeropage;
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pthread_attr_t attr;
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/* pthread_mutex_t starts at page offset 0 */
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#define area_mutex(___area, ___nr) \
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((pthread_mutex_t *) ((___area) + (___nr)*page_size))
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/*
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* count is placed in the page after pthread_mutex_t naturally aligned
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* to avoid non alignment faults on non-x86 archs.
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*/
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#define area_count(___area, ___nr) \
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((volatile unsigned long long *) ((unsigned long) \
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((___area) + (___nr)*page_size + \
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sizeof(pthread_mutex_t) + \
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sizeof(unsigned long long) - 1) & \
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~(unsigned long)(sizeof(unsigned long long) \
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- 1)))
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static int anon_release_pages(char *rel_area)
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{
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int ret = 0;
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if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED)) {
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perror("madvise");
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ret = 1;
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}
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return ret;
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}
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static void anon_allocate_area(void **alloc_area)
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{
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if (posix_memalign(alloc_area, page_size, nr_pages * page_size)) {
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fprintf(stderr, "out of memory\n");
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*alloc_area = NULL;
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}
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}
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/* HugeTLB memory */
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static int hugetlb_release_pages(char *rel_area)
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{
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int ret = 0;
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if (fallocate(huge_fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
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rel_area == huge_fd_off0 ? 0 :
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nr_pages * page_size,
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nr_pages * page_size)) {
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perror("fallocate");
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ret = 1;
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}
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return ret;
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}
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static void hugetlb_allocate_area(void **alloc_area)
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{
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*alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
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MAP_PRIVATE | MAP_HUGETLB, huge_fd,
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*alloc_area == area_src ? 0 :
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nr_pages * page_size);
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if (*alloc_area == MAP_FAILED) {
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fprintf(stderr, "mmap of hugetlbfs file failed\n");
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*alloc_area = NULL;
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}
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if (*alloc_area == area_src)
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huge_fd_off0 = *alloc_area;
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}
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/* Shared memory */
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static int shmem_release_pages(char *rel_area)
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{
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int ret = 0;
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if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE)) {
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perror("madvise");
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ret = 1;
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}
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return ret;
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}
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static void shmem_allocate_area(void **alloc_area)
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{
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*alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
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MAP_ANONYMOUS | MAP_SHARED, -1, 0);
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if (*alloc_area == MAP_FAILED) {
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fprintf(stderr, "shared memory mmap failed\n");
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*alloc_area = NULL;
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}
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}
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struct uffd_test_ops {
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unsigned long expected_ioctls;
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void (*allocate_area)(void **alloc_area);
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int (*release_pages)(char *rel_area);
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};
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#define ANON_EXPECTED_IOCTLS ((1 << _UFFDIO_WAKE) | \
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(1 << _UFFDIO_COPY) | \
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(1 << _UFFDIO_ZEROPAGE))
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static struct uffd_test_ops anon_uffd_test_ops = {
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.expected_ioctls = ANON_EXPECTED_IOCTLS,
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.allocate_area = anon_allocate_area,
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.release_pages = anon_release_pages,
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};
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static struct uffd_test_ops shmem_uffd_test_ops = {
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.expected_ioctls = UFFD_API_RANGE_IOCTLS_BASIC,
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.allocate_area = shmem_allocate_area,
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.release_pages = shmem_release_pages,
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};
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static struct uffd_test_ops hugetlb_uffd_test_ops = {
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.expected_ioctls = UFFD_API_RANGE_IOCTLS_BASIC,
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.allocate_area = hugetlb_allocate_area,
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.release_pages = hugetlb_release_pages,
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};
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static struct uffd_test_ops *uffd_test_ops;
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static int my_bcmp(char *str1, char *str2, size_t n)
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{
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unsigned long i;
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for (i = 0; i < n; i++)
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if (str1[i] != str2[i])
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return 1;
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return 0;
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}
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static void *locking_thread(void *arg)
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{
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unsigned long cpu = (unsigned long) arg;
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struct random_data rand;
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unsigned long page_nr = *(&(page_nr)); /* uninitialized warning */
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int32_t rand_nr;
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unsigned long long count;
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char randstate[64];
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unsigned int seed;
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time_t start;
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if (bounces & BOUNCE_RANDOM) {
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seed = (unsigned int) time(NULL) - bounces;
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if (!(bounces & BOUNCE_RACINGFAULTS))
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seed += cpu;
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bzero(&rand, sizeof(rand));
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bzero(&randstate, sizeof(randstate));
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if (initstate_r(seed, randstate, sizeof(randstate), &rand))
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fprintf(stderr, "srandom_r error\n"), exit(1);
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} else {
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page_nr = -bounces;
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if (!(bounces & BOUNCE_RACINGFAULTS))
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page_nr += cpu * nr_pages_per_cpu;
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}
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while (!finished) {
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if (bounces & BOUNCE_RANDOM) {
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if (random_r(&rand, &rand_nr))
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fprintf(stderr, "random_r 1 error\n"), exit(1);
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page_nr = rand_nr;
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if (sizeof(page_nr) > sizeof(rand_nr)) {
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if (random_r(&rand, &rand_nr))
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fprintf(stderr, "random_r 2 error\n"), exit(1);
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page_nr |= (((unsigned long) rand_nr) << 16) <<
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16;
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}
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} else
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page_nr += 1;
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page_nr %= nr_pages;
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start = time(NULL);
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if (bounces & BOUNCE_VERIFY) {
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count = *area_count(area_dst, page_nr);
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if (!count)
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fprintf(stderr,
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"page_nr %lu wrong count %Lu %Lu\n",
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page_nr, count,
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count_verify[page_nr]), exit(1);
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/*
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* We can't use bcmp (or memcmp) because that
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* returns 0 erroneously if the memory is
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* changing under it (even if the end of the
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* page is never changing and always
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* different).
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*/
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#if 1
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if (!my_bcmp(area_dst + page_nr * page_size, zeropage,
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page_size))
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fprintf(stderr,
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"my_bcmp page_nr %lu wrong count %Lu %Lu\n",
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page_nr, count,
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count_verify[page_nr]), exit(1);
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#else
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unsigned long loops;
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loops = 0;
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/* uncomment the below line to test with mutex */
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/* pthread_mutex_lock(area_mutex(area_dst, page_nr)); */
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while (!bcmp(area_dst + page_nr * page_size, zeropage,
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page_size)) {
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loops += 1;
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if (loops > 10)
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break;
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}
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/* uncomment below line to test with mutex */
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/* pthread_mutex_unlock(area_mutex(area_dst, page_nr)); */
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if (loops) {
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fprintf(stderr,
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"page_nr %lu all zero thread %lu %p %lu\n",
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page_nr, cpu, area_dst + page_nr * page_size,
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loops);
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if (loops > 10)
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exit(1);
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}
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#endif
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}
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pthread_mutex_lock(area_mutex(area_dst, page_nr));
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count = *area_count(area_dst, page_nr);
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if (count != count_verify[page_nr]) {
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fprintf(stderr,
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"page_nr %lu memory corruption %Lu %Lu\n",
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page_nr, count,
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count_verify[page_nr]), exit(1);
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}
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count++;
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*area_count(area_dst, page_nr) = count_verify[page_nr] = count;
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pthread_mutex_unlock(area_mutex(area_dst, page_nr));
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if (time(NULL) - start > 1)
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fprintf(stderr,
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"userfault too slow %ld "
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"possible false positive with overcommit\n",
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time(NULL) - start);
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}
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return NULL;
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}
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static int copy_page(int ufd, unsigned long offset)
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{
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struct uffdio_copy uffdio_copy;
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if (offset >= nr_pages * page_size)
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fprintf(stderr, "unexpected offset %lu\n",
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offset), exit(1);
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uffdio_copy.dst = (unsigned long) area_dst + offset;
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uffdio_copy.src = (unsigned long) area_src + offset;
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uffdio_copy.len = page_size;
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uffdio_copy.mode = 0;
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uffdio_copy.copy = 0;
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if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) {
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/* real retval in ufdio_copy.copy */
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if (uffdio_copy.copy != -EEXIST)
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fprintf(stderr, "UFFDIO_COPY error %Ld\n",
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uffdio_copy.copy), exit(1);
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} else if (uffdio_copy.copy != page_size) {
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fprintf(stderr, "UFFDIO_COPY unexpected copy %Ld\n",
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uffdio_copy.copy), exit(1);
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} else
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return 1;
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return 0;
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}
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static void *uffd_poll_thread(void *arg)
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{
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unsigned long cpu = (unsigned long) arg;
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struct pollfd pollfd[2];
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struct uffd_msg msg;
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struct uffdio_register uffd_reg;
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int ret;
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unsigned long offset;
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char tmp_chr;
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unsigned long userfaults = 0;
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pollfd[0].fd = uffd;
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pollfd[0].events = POLLIN;
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pollfd[1].fd = pipefd[cpu*2];
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pollfd[1].events = POLLIN;
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for (;;) {
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ret = poll(pollfd, 2, -1);
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if (!ret)
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fprintf(stderr, "poll error %d\n", ret), exit(1);
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if (ret < 0)
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perror("poll"), exit(1);
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if (pollfd[1].revents & POLLIN) {
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if (read(pollfd[1].fd, &tmp_chr, 1) != 1)
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fprintf(stderr, "read pipefd error\n"),
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exit(1);
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break;
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}
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if (!(pollfd[0].revents & POLLIN))
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fprintf(stderr, "pollfd[0].revents %d\n",
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pollfd[0].revents), exit(1);
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ret = read(uffd, &msg, sizeof(msg));
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if (ret < 0) {
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if (errno == EAGAIN)
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continue;
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perror("nonblocking read error"), exit(1);
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}
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switch (msg.event) {
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default:
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fprintf(stderr, "unexpected msg event %u\n",
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msg.event), exit(1);
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break;
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case UFFD_EVENT_PAGEFAULT:
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if (msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
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fprintf(stderr, "unexpected write fault\n"), exit(1);
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offset = (char *)(unsigned long)msg.arg.pagefault.address -
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area_dst;
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offset &= ~(page_size-1);
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if (copy_page(uffd, offset))
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userfaults++;
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break;
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case UFFD_EVENT_FORK:
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uffd = msg.arg.fork.ufd;
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pollfd[0].fd = uffd;
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break;
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case UFFD_EVENT_REMOVE:
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uffd_reg.range.start = msg.arg.remove.start;
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uffd_reg.range.len = msg.arg.remove.end -
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msg.arg.remove.start;
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if (ioctl(uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
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fprintf(stderr, "remove failure\n"), exit(1);
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break;
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case UFFD_EVENT_REMAP:
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area_dst = (char *)(unsigned long)msg.arg.remap.to;
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break;
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}
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}
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return (void *)userfaults;
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}
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pthread_mutex_t uffd_read_mutex = PTHREAD_MUTEX_INITIALIZER;
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static void *uffd_read_thread(void *arg)
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{
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unsigned long *this_cpu_userfaults;
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struct uffd_msg msg;
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unsigned long offset;
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int ret;
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this_cpu_userfaults = (unsigned long *) arg;
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*this_cpu_userfaults = 0;
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pthread_mutex_unlock(&uffd_read_mutex);
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/* from here cancellation is ok */
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for (;;) {
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ret = read(uffd, &msg, sizeof(msg));
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if (ret != sizeof(msg)) {
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if (ret < 0)
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perror("blocking read error"), exit(1);
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else
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fprintf(stderr, "short read\n"), exit(1);
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}
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if (msg.event != UFFD_EVENT_PAGEFAULT)
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fprintf(stderr, "unexpected msg event %u\n",
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msg.event), exit(1);
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if (bounces & BOUNCE_VERIFY &&
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msg.arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
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fprintf(stderr, "unexpected write fault\n"), exit(1);
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offset = (char *)(unsigned long)msg.arg.pagefault.address -
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area_dst;
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offset &= ~(page_size-1);
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if (copy_page(uffd, offset))
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(*this_cpu_userfaults)++;
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}
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return (void *)NULL;
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}
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static void *background_thread(void *arg)
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{
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unsigned long cpu = (unsigned long) arg;
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unsigned long page_nr;
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for (page_nr = cpu * nr_pages_per_cpu;
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page_nr < (cpu+1) * nr_pages_per_cpu;
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page_nr++)
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copy_page(uffd, page_nr * page_size);
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return NULL;
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}
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static int stress(unsigned long *userfaults)
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{
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unsigned long cpu;
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pthread_t locking_threads[nr_cpus];
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pthread_t uffd_threads[nr_cpus];
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pthread_t background_threads[nr_cpus];
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void **_userfaults = (void **) userfaults;
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|
|
finished = 0;
|
|
for (cpu = 0; cpu < nr_cpus; cpu++) {
|
|
if (pthread_create(&locking_threads[cpu], &attr,
|
|
locking_thread, (void *)cpu))
|
|
return 1;
|
|
if (bounces & BOUNCE_POLL) {
|
|
if (pthread_create(&uffd_threads[cpu], &attr,
|
|
uffd_poll_thread, (void *)cpu))
|
|
return 1;
|
|
} else {
|
|
if (pthread_create(&uffd_threads[cpu], &attr,
|
|
uffd_read_thread,
|
|
&_userfaults[cpu]))
|
|
return 1;
|
|
pthread_mutex_lock(&uffd_read_mutex);
|
|
}
|
|
if (pthread_create(&background_threads[cpu], &attr,
|
|
background_thread, (void *)cpu))
|
|
return 1;
|
|
}
|
|
for (cpu = 0; cpu < nr_cpus; cpu++)
|
|
if (pthread_join(background_threads[cpu], NULL))
|
|
return 1;
|
|
|
|
/*
|
|
* Be strict and immediately zap area_src, the whole area has
|
|
* been transferred already by the background treads. The
|
|
* area_src could then be faulted in in a racy way by still
|
|
* running uffdio_threads reading zeropages after we zapped
|
|
* area_src (but they're guaranteed to get -EEXIST from
|
|
* UFFDIO_COPY without writing zero pages into area_dst
|
|
* because the background threads already completed).
|
|
*/
|
|
if (uffd_test_ops->release_pages(area_src))
|
|
return 1;
|
|
|
|
for (cpu = 0; cpu < nr_cpus; cpu++) {
|
|
char c;
|
|
if (bounces & BOUNCE_POLL) {
|
|
if (write(pipefd[cpu*2+1], &c, 1) != 1) {
|
|
fprintf(stderr, "pipefd write error\n");
|
|
return 1;
|
|
}
|
|
if (pthread_join(uffd_threads[cpu], &_userfaults[cpu]))
|
|
return 1;
|
|
} else {
|
|
if (pthread_cancel(uffd_threads[cpu]))
|
|
return 1;
|
|
if (pthread_join(uffd_threads[cpu], NULL))
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
finished = 1;
|
|
for (cpu = 0; cpu < nr_cpus; cpu++)
|
|
if (pthread_join(locking_threads[cpu], NULL))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int userfaultfd_open(int features)
|
|
{
|
|
struct uffdio_api uffdio_api;
|
|
|
|
uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
|
|
if (uffd < 0) {
|
|
fprintf(stderr,
|
|
"userfaultfd syscall not available in this kernel\n");
|
|
return 1;
|
|
}
|
|
uffd_flags = fcntl(uffd, F_GETFD, NULL);
|
|
|
|
uffdio_api.api = UFFD_API;
|
|
uffdio_api.features = features;
|
|
if (ioctl(uffd, UFFDIO_API, &uffdio_api)) {
|
|
fprintf(stderr, "UFFDIO_API\n");
|
|
return 1;
|
|
}
|
|
if (uffdio_api.api != UFFD_API) {
|
|
fprintf(stderr, "UFFDIO_API error %Lu\n", uffdio_api.api);
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* For non-cooperative userfaultfd test we fork() a process that will
|
|
* generate pagefaults, will mremap the area monitored by the
|
|
* userfaultfd and at last this process will release the monitored
|
|
* area.
|
|
* For the anonymous and shared memory the area is divided into two
|
|
* parts, the first part is accessed before mremap, and the second
|
|
* part is accessed after mremap. Since hugetlbfs does not support
|
|
* mremap, the entire monitored area is accessed in a single pass for
|
|
* HUGETLB_TEST.
|
|
* The release of the pages currently generates event for shmem and
|
|
* anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
|
|
* for hugetlb.
|
|
*/
|
|
static int faulting_process(void)
|
|
{
|
|
unsigned long nr;
|
|
unsigned long long count;
|
|
unsigned long split_nr_pages;
|
|
|
|
if (test_type != TEST_HUGETLB)
|
|
split_nr_pages = (nr_pages + 1) / 2;
|
|
else
|
|
split_nr_pages = nr_pages;
|
|
|
|
for (nr = 0; nr < split_nr_pages; nr++) {
|
|
count = *area_count(area_dst, nr);
|
|
if (count != count_verify[nr]) {
|
|
fprintf(stderr,
|
|
"nr %lu memory corruption %Lu %Lu\n",
|
|
nr, count,
|
|
count_verify[nr]), exit(1);
|
|
}
|
|
}
|
|
|
|
if (test_type == TEST_HUGETLB)
|
|
return 0;
|
|
|
|
area_dst = mremap(area_dst, nr_pages * page_size, nr_pages * page_size,
|
|
MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
|
|
if (area_dst == MAP_FAILED)
|
|
perror("mremap"), exit(1);
|
|
|
|
for (; nr < nr_pages; nr++) {
|
|
count = *area_count(area_dst, nr);
|
|
if (count != count_verify[nr]) {
|
|
fprintf(stderr,
|
|
"nr %lu memory corruption %Lu %Lu\n",
|
|
nr, count,
|
|
count_verify[nr]), exit(1);
|
|
}
|
|
}
|
|
|
|
if (uffd_test_ops->release_pages(area_dst))
|
|
return 1;
|
|
|
|
for (nr = 0; nr < nr_pages; nr++) {
|
|
if (my_bcmp(area_dst + nr * page_size, zeropage, page_size))
|
|
fprintf(stderr, "nr %lu is not zero\n", nr), exit(1);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int uffdio_zeropage(int ufd, unsigned long offset)
|
|
{
|
|
struct uffdio_zeropage uffdio_zeropage;
|
|
int ret;
|
|
unsigned long has_zeropage;
|
|
|
|
has_zeropage = uffd_test_ops->expected_ioctls & (1 << _UFFDIO_ZEROPAGE);
|
|
|
|
if (offset >= nr_pages * page_size)
|
|
fprintf(stderr, "unexpected offset %lu\n",
|
|
offset), exit(1);
|
|
uffdio_zeropage.range.start = (unsigned long) area_dst + offset;
|
|
uffdio_zeropage.range.len = page_size;
|
|
uffdio_zeropage.mode = 0;
|
|
ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
|
|
if (ret) {
|
|
/* real retval in ufdio_zeropage.zeropage */
|
|
if (has_zeropage) {
|
|
if (uffdio_zeropage.zeropage == -EEXIST)
|
|
fprintf(stderr, "UFFDIO_ZEROPAGE -EEXIST\n"),
|
|
exit(1);
|
|
else
|
|
fprintf(stderr, "UFFDIO_ZEROPAGE error %Ld\n",
|
|
uffdio_zeropage.zeropage), exit(1);
|
|
} else {
|
|
if (uffdio_zeropage.zeropage != -EINVAL)
|
|
fprintf(stderr,
|
|
"UFFDIO_ZEROPAGE not -EINVAL %Ld\n",
|
|
uffdio_zeropage.zeropage), exit(1);
|
|
}
|
|
} else if (has_zeropage) {
|
|
if (uffdio_zeropage.zeropage != page_size) {
|
|
fprintf(stderr, "UFFDIO_ZEROPAGE unexpected %Ld\n",
|
|
uffdio_zeropage.zeropage), exit(1);
|
|
} else
|
|
return 1;
|
|
} else {
|
|
fprintf(stderr,
|
|
"UFFDIO_ZEROPAGE succeeded %Ld\n",
|
|
uffdio_zeropage.zeropage), exit(1);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* exercise UFFDIO_ZEROPAGE */
|
|
static int userfaultfd_zeropage_test(void)
|
|
{
|
|
struct uffdio_register uffdio_register;
|
|
unsigned long expected_ioctls;
|
|
|
|
printf("testing UFFDIO_ZEROPAGE: ");
|
|
fflush(stdout);
|
|
|
|
if (uffd_test_ops->release_pages(area_dst))
|
|
return 1;
|
|
|
|
if (userfaultfd_open(0) < 0)
|
|
return 1;
|
|
uffdio_register.range.start = (unsigned long) area_dst;
|
|
uffdio_register.range.len = nr_pages * page_size;
|
|
uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
|
|
if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
|
|
fprintf(stderr, "register failure\n"), exit(1);
|
|
|
|
expected_ioctls = uffd_test_ops->expected_ioctls;
|
|
if ((uffdio_register.ioctls & expected_ioctls) !=
|
|
expected_ioctls)
|
|
fprintf(stderr,
|
|
"unexpected missing ioctl for anon memory\n"),
|
|
exit(1);
|
|
|
|
if (uffdio_zeropage(uffd, 0)) {
|
|
if (my_bcmp(area_dst, zeropage, page_size))
|
|
fprintf(stderr, "zeropage is not zero\n"), exit(1);
|
|
}
|
|
|
|
close(uffd);
|
|
printf("done.\n");
|
|
return 0;
|
|
}
|
|
|
|
static int userfaultfd_events_test(void)
|
|
{
|
|
struct uffdio_register uffdio_register;
|
|
unsigned long expected_ioctls;
|
|
unsigned long userfaults;
|
|
pthread_t uffd_mon;
|
|
int err, features;
|
|
pid_t pid;
|
|
char c;
|
|
|
|
printf("testing events (fork, remap, remove): ");
|
|
fflush(stdout);
|
|
|
|
if (uffd_test_ops->release_pages(area_dst))
|
|
return 1;
|
|
|
|
features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP |
|
|
UFFD_FEATURE_EVENT_REMOVE;
|
|
if (userfaultfd_open(features) < 0)
|
|
return 1;
|
|
fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
|
|
|
|
uffdio_register.range.start = (unsigned long) area_dst;
|
|
uffdio_register.range.len = nr_pages * page_size;
|
|
uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
|
|
if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
|
|
fprintf(stderr, "register failure\n"), exit(1);
|
|
|
|
expected_ioctls = uffd_test_ops->expected_ioctls;
|
|
if ((uffdio_register.ioctls & expected_ioctls) !=
|
|
expected_ioctls)
|
|
fprintf(stderr,
|
|
"unexpected missing ioctl for anon memory\n"),
|
|
exit(1);
|
|
|
|
if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, NULL))
|
|
perror("uffd_poll_thread create"), exit(1);
|
|
|
|
pid = fork();
|
|
if (pid < 0)
|
|
perror("fork"), exit(1);
|
|
|
|
if (!pid)
|
|
return faulting_process();
|
|
|
|
waitpid(pid, &err, 0);
|
|
if (err)
|
|
fprintf(stderr, "faulting process failed\n"), exit(1);
|
|
|
|
if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
|
|
perror("pipe write"), exit(1);
|
|
if (pthread_join(uffd_mon, (void **)&userfaults))
|
|
return 1;
|
|
|
|
close(uffd);
|
|
printf("userfaults: %ld\n", userfaults);
|
|
|
|
return userfaults != nr_pages;
|
|
}
|
|
|
|
static int userfaultfd_stress(void)
|
|
{
|
|
void *area;
|
|
char *tmp_area;
|
|
unsigned long nr;
|
|
struct uffdio_register uffdio_register;
|
|
unsigned long cpu;
|
|
int err;
|
|
unsigned long userfaults[nr_cpus];
|
|
|
|
uffd_test_ops->allocate_area((void **)&area_src);
|
|
if (!area_src)
|
|
return 1;
|
|
uffd_test_ops->allocate_area((void **)&area_dst);
|
|
if (!area_dst)
|
|
return 1;
|
|
|
|
if (userfaultfd_open(0) < 0)
|
|
return 1;
|
|
|
|
count_verify = malloc(nr_pages * sizeof(unsigned long long));
|
|
if (!count_verify) {
|
|
perror("count_verify");
|
|
return 1;
|
|
}
|
|
|
|
for (nr = 0; nr < nr_pages; nr++) {
|
|
*area_mutex(area_src, nr) = (pthread_mutex_t)
|
|
PTHREAD_MUTEX_INITIALIZER;
|
|
count_verify[nr] = *area_count(area_src, nr) = 1;
|
|
/*
|
|
* In the transition between 255 to 256, powerpc will
|
|
* read out of order in my_bcmp and see both bytes as
|
|
* zero, so leave a placeholder below always non-zero
|
|
* after the count, to avoid my_bcmp to trigger false
|
|
* positives.
|
|
*/
|
|
*(area_count(area_src, nr) + 1) = 1;
|
|
}
|
|
|
|
pipefd = malloc(sizeof(int) * nr_cpus * 2);
|
|
if (!pipefd) {
|
|
perror("pipefd");
|
|
return 1;
|
|
}
|
|
for (cpu = 0; cpu < nr_cpus; cpu++) {
|
|
if (pipe2(&pipefd[cpu*2], O_CLOEXEC | O_NONBLOCK)) {
|
|
perror("pipe");
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
if (posix_memalign(&area, page_size, page_size)) {
|
|
fprintf(stderr, "out of memory\n");
|
|
return 1;
|
|
}
|
|
zeropage = area;
|
|
bzero(zeropage, page_size);
|
|
|
|
pthread_mutex_lock(&uffd_read_mutex);
|
|
|
|
pthread_attr_init(&attr);
|
|
pthread_attr_setstacksize(&attr, 16*1024*1024);
|
|
|
|
err = 0;
|
|
while (bounces--) {
|
|
unsigned long expected_ioctls;
|
|
|
|
printf("bounces: %d, mode:", bounces);
|
|
if (bounces & BOUNCE_RANDOM)
|
|
printf(" rnd");
|
|
if (bounces & BOUNCE_RACINGFAULTS)
|
|
printf(" racing");
|
|
if (bounces & BOUNCE_VERIFY)
|
|
printf(" ver");
|
|
if (bounces & BOUNCE_POLL)
|
|
printf(" poll");
|
|
printf(", ");
|
|
fflush(stdout);
|
|
|
|
if (bounces & BOUNCE_POLL)
|
|
fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
|
|
else
|
|
fcntl(uffd, F_SETFL, uffd_flags & ~O_NONBLOCK);
|
|
|
|
/* register */
|
|
uffdio_register.range.start = (unsigned long) area_dst;
|
|
uffdio_register.range.len = nr_pages * page_size;
|
|
uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
|
|
if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) {
|
|
fprintf(stderr, "register failure\n");
|
|
return 1;
|
|
}
|
|
expected_ioctls = uffd_test_ops->expected_ioctls;
|
|
if ((uffdio_register.ioctls & expected_ioctls) !=
|
|
expected_ioctls) {
|
|
fprintf(stderr,
|
|
"unexpected missing ioctl for anon memory\n");
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* The madvise done previously isn't enough: some
|
|
* uffd_thread could have read userfaults (one of
|
|
* those already resolved by the background thread)
|
|
* and it may be in the process of calling
|
|
* UFFDIO_COPY. UFFDIO_COPY will read the zapped
|
|
* area_src and it would map a zero page in it (of
|
|
* course such a UFFDIO_COPY is perfectly safe as it'd
|
|
* return -EEXIST). The problem comes at the next
|
|
* bounce though: that racing UFFDIO_COPY would
|
|
* generate zeropages in the area_src, so invalidating
|
|
* the previous MADV_DONTNEED. Without this additional
|
|
* MADV_DONTNEED those zeropages leftovers in the
|
|
* area_src would lead to -EEXIST failure during the
|
|
* next bounce, effectively leaving a zeropage in the
|
|
* area_dst.
|
|
*
|
|
* Try to comment this out madvise to see the memory
|
|
* corruption being caught pretty quick.
|
|
*
|
|
* khugepaged is also inhibited to collapse THP after
|
|
* MADV_DONTNEED only after the UFFDIO_REGISTER, so it's
|
|
* required to MADV_DONTNEED here.
|
|
*/
|
|
if (uffd_test_ops->release_pages(area_dst))
|
|
return 1;
|
|
|
|
/* bounce pass */
|
|
if (stress(userfaults))
|
|
return 1;
|
|
|
|
/* unregister */
|
|
if (ioctl(uffd, UFFDIO_UNREGISTER, &uffdio_register.range)) {
|
|
fprintf(stderr, "register failure\n");
|
|
return 1;
|
|
}
|
|
|
|
/* verification */
|
|
if (bounces & BOUNCE_VERIFY) {
|
|
for (nr = 0; nr < nr_pages; nr++) {
|
|
if (*area_count(area_dst, nr) != count_verify[nr]) {
|
|
fprintf(stderr,
|
|
"error area_count %Lu %Lu %lu\n",
|
|
*area_count(area_src, nr),
|
|
count_verify[nr],
|
|
nr);
|
|
err = 1;
|
|
bounces = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* prepare next bounce */
|
|
tmp_area = area_src;
|
|
area_src = area_dst;
|
|
area_dst = tmp_area;
|
|
|
|
printf("userfaults:");
|
|
for (cpu = 0; cpu < nr_cpus; cpu++)
|
|
printf(" %lu", userfaults[cpu]);
|
|
printf("\n");
|
|
}
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
close(uffd);
|
|
return userfaultfd_zeropage_test() || userfaultfd_events_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;
|
|
}
|
|
|
|
static void set_test_type(const char *type)
|
|
{
|
|
if (!strcmp(type, "anon")) {
|
|
test_type = TEST_ANON;
|
|
uffd_test_ops = &anon_uffd_test_ops;
|
|
} else if (!strcmp(type, "hugetlb")) {
|
|
test_type = TEST_HUGETLB;
|
|
uffd_test_ops = &hugetlb_uffd_test_ops;
|
|
} else if (!strcmp(type, "shmem")) {
|
|
test_type = TEST_SHMEM;
|
|
uffd_test_ops = &shmem_uffd_test_ops;
|
|
} else {
|
|
fprintf(stderr, "Unknown test type: %s\n", type), exit(1);
|
|
}
|
|
|
|
if (test_type == TEST_HUGETLB)
|
|
page_size = default_huge_page_size();
|
|
else
|
|
page_size = sysconf(_SC_PAGE_SIZE);
|
|
|
|
if (!page_size)
|
|
fprintf(stderr, "Unable to determine 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);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
if (argc < 4)
|
|
fprintf(stderr, "Usage: <test type> <MiB> <bounces> [hugetlbfs_file]\n"),
|
|
exit(1);
|
|
|
|
set_test_type(argv[1]);
|
|
|
|
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
|
|
nr_pages_per_cpu = atol(argv[2]) * 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[3]);
|
|
if (bounces <= 0) {
|
|
fprintf(stderr, "invalid bounces\n");
|
|
fprintf(stderr, "Usage: <MiB> <bounces>\n"), exit(1);
|
|
}
|
|
nr_pages = nr_pages_per_cpu * nr_cpus;
|
|
|
|
if (test_type == TEST_HUGETLB) {
|
|
if (argc < 5)
|
|
fprintf(stderr, "Usage: hugetlb <MiB> <bounces> <hugetlbfs_file>\n"),
|
|
exit(1);
|
|
huge_fd = open(argv[4], 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();
|
|
}
|
|
|
|
#else /* __NR_userfaultfd */
|
|
|
|
#warning "missing __NR_userfaultfd definition"
|
|
|
|
int main(void)
|
|
{
|
|
printf("skip: Skipping userfaultfd test (missing __NR_userfaultfd)\n");
|
|
return 0;
|
|
}
|
|
|
|
#endif /* __NR_userfaultfd */
|