diff options
| -rw-r--r-- | mm/Kconfig | 9 | ||||
| -rw-r--r-- | mm/Makefile | 1 | ||||
| -rw-r--r-- | mm/gup_benchmark.c | 100 | ||||
| -rw-r--r-- | tools/testing/selftests/vm/Makefile | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/vm/gup_benchmark.c | 91 |
5 files changed, 202 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 9c4bdddd80c2..03ff7703d322 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -756,3 +756,12 @@ config PERCPU_STATS This feature collects and exposes statistics via debugfs. The information includes global and per chunk statistics, which can be used to help understand percpu memory usage. + +config GUP_BENCHMARK + bool "Enable infrastructure for get_user_pages_fast() benchmarking" + default n + help + Provides /sys/kernel/debug/gup_benchmark that helps with testing + performance of get_user_pages_fast(). + + See tools/testing/selftests/vm/gup_benchmark.c diff --git a/mm/Makefile b/mm/Makefile index e7ebd176fb93..e669f02c5a54 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -80,6 +80,7 @@ obj-$(CONFIG_PAGE_COUNTER) += page_counter.o obj-$(CONFIG_MEMCG) += memcontrol.o vmpressure.o obj-$(CONFIG_MEMCG_SWAP) += swap_cgroup.o obj-$(CONFIG_CGROUP_HUGETLB) += hugetlb_cgroup.o +obj-$(CONFIG_GUP_BENCHMARK) += gup_benchmark.o obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c new file mode 100644 index 000000000000..5c8e2abeaa15 --- /dev/null +++ b/mm/gup_benchmark.c @@ -0,0 +1,100 @@ +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/ktime.h> +#include <linux/debugfs.h> + +#define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) + +struct gup_benchmark { + __u64 delta_usec; + __u64 addr; + __u64 size; + __u32 nr_pages_per_call; + __u32 flags; +}; + +static int __gup_benchmark_ioctl(unsigned int cmd, + struct gup_benchmark *gup) +{ + ktime_t start_time, end_time; + unsigned long i, nr, nr_pages, addr, next; + struct page **pages; + + nr_pages = gup->size / PAGE_SIZE; + pages = kvmalloc(sizeof(void *) * nr_pages, GFP_KERNEL); + if (!pages) + return -ENOMEM; + + i = 0; + nr = gup->nr_pages_per_call; + start_time = ktime_get(); + for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) { + if (nr != gup->nr_pages_per_call) + break; + + next = addr + nr * PAGE_SIZE; + if (next > gup->addr + gup->size) { + next = gup->addr + gup->size; + nr = (next - addr) / PAGE_SIZE; + } + + nr = get_user_pages_fast(addr, nr, gup->flags & 1, pages + i); + i += nr; + } + end_time = ktime_get(); + + gup->delta_usec = ktime_us_delta(end_time, start_time); + gup->size = addr - gup->addr; + + for (i = 0; i < nr_pages; i++) { + if (!pages[i]) + break; + put_page(pages[i]); + } + + kvfree(pages); + return 0; +} + +static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd, + unsigned long arg) +{ + struct gup_benchmark gup; + int ret; + + if (cmd != GUP_FAST_BENCHMARK) + return -EINVAL; + + if (copy_from_user(&gup, (void __user *)arg, sizeof(gup))) + return -EFAULT; + + ret = __gup_benchmark_ioctl(cmd, &gup); + if (ret) + return ret; + + if (copy_to_user((void __user *)arg, &gup, sizeof(gup))) + return -EFAULT; + + return 0; +} + +static const struct file_operations gup_benchmark_fops = { + .open = nonseekable_open, + .unlocked_ioctl = gup_benchmark_ioctl, +}; + +static int gup_benchmark_init(void) +{ + void *ret; + + ret = debugfs_create_file_unsafe("gup_benchmark", 0600, NULL, NULL, + &gup_benchmark_fops); + if (!ret) + pr_warn("Failed to create gup_benchmark in debugfs"); + + return 0; +} + +late_initcall(gup_benchmark_init); diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index e49eca1915f8..7f45806bd863 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -18,6 +18,7 @@ TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd TEST_GEN_FILES += mlock-random-test TEST_GEN_FILES += virtual_address_range +TEST_GEN_FILES += gup_benchmark TEST_PROGS := run_vmtests diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c new file mode 100644 index 000000000000..36df55132036 --- /dev/null +++ b/tools/testing/selftests/vm/gup_benchmark.c @@ -0,0 +1,91 @@ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/prctl.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include <linux/types.h> + +#define MB (1UL << 20) +#define PAGE_SIZE sysconf(_SC_PAGESIZE) + +#define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) + +struct gup_benchmark { + __u64 delta_usec; + __u64 addr; + __u64 size; + __u32 nr_pages_per_call; + __u32 flags; +}; + +int main(int argc, char **argv) +{ + struct gup_benchmark gup; + unsigned long size = 128 * MB; + int i, fd, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0; + char *p; + + while ((opt = getopt(argc, argv, "m:r:n:tT")) != -1) { + switch (opt) { + case 'm': + size = atoi(optarg) * MB; + break; + case 'r': + repeats = atoi(optarg); + break; + case 'n': + nr_pages = atoi(optarg); + break; + case 't': + thp = 1; + break; + case 'T': + thp = 0; + break; + case 'w': + write = 1; + default: + return -1; + } + } + + gup.nr_pages_per_call = nr_pages; + gup.flags = write; + + fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR); + if (fd == -1) + perror("open"), exit(1); + + p = mmap(NULL, size, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (p == MAP_FAILED) + perror("mmap"), exit(1); + gup.addr = (unsigned long)p; + + if (thp == 1) + madvise(p, size, MADV_HUGEPAGE); + else if (thp == 0) + madvise(p, size, MADV_NOHUGEPAGE); + + for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE) + p[0] = 0; + + for (i = 0; i < repeats; i++) { + gup.size = size; + if (ioctl(fd, GUP_FAST_BENCHMARK, &gup)) + perror("ioctl"), exit(1); + + printf("Time: %lld us", gup.delta_usec); + if (gup.size != size) + printf(", truncated (size: %lld)", gup.size); + printf("\n"); + } + + return 0; +} |