Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-26 06:02:05 +00:00
Code Issues Packages Projects Releases Wiki Activity

selftests: vm: add KSM huge pages merging time test

Browse Source 
Add test case of KSM merging time using mostly huge pages

Link: https://lkml.kernel.org/r/20211013044045.360251-1-pedrodemargomes@gmail.com
Signed-off-by: Pedro Demarchi Gomes <pedrodemargomes@gmail.com>
Cc: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pedro Demarchi Gomes 2021-11-05 13:43:56 -07:00 committed by Linus Torvalds
parent e3820ab252
commit 3252548996
1 changed files with 124 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

125
tools/testing/selftests/vm/ksm_tests.c
View File

@ -5,6 +5,10 @@
#include <time.h>
#include <string.h>
#include <numa.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdint.h>
#include <err.h>
#include "../kselftest.h"
#include "../../../../include/vdso/time64.h"
@ -18,6 +22,15 @@
#define KSM_MERGE_ACROSS_NODES_DEFAULT true
#define MB (1ul << 20)
#define PAGE_SHIFT 12
#define HPAGE_SHIFT 21
#define PAGE_SIZE (1 << PAGE_SHIFT)
#define HPAGE_SIZE (1 << HPAGE_SHIFT)
#define PAGEMAP_PRESENT(ent) (((ent) & (1ull << 63)) != 0)
#define PAGEMAP_PFN(ent) ((ent) & ((1ull << 55) - 1))
struct ksm_sysfs {
unsigned long max_page_sharing;
unsigned long merge_across_nodes;
@ -34,6 +47,7 @@ enum ksm_test_name {
CHECK_KSM_ZERO_PAGE_MERGE,
CHECK_KSM_NUMA_MERGE,
KSM_MERGE_TIME,
KSM_MERGE_TIME_HUGE_PAGES,
KSM_COW_TIME
};
@ -99,6 +113,9 @@ static void print_help(void)
" -U (page unmerging)\n"
" -P evaluate merging time and speed.\n"
" For this test, the size of duplicated memory area (in MiB)\n"
" must be provided using -s option\n"
" -H evaluate merging time and speed of area allocated mostly with huge pages\n"
" For this test, the size of duplicated memory area (in MiB)\n"
" must be provided using -s option\n"
" -C evaluate the time required to break COW of merged pages.\n\n");
@ -439,6 +456,101 @@ err_out:
return KSFT_FAIL;
}
int64_t allocate_transhuge(void *ptr, int pagemap_fd)
{
uint64_t ent[2];
/* drop pmd */
if (mmap(ptr, HPAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_FIXED | MAP_ANONYMOUS |
MAP_NORESERVE | MAP_PRIVATE, -1, 0) != ptr)
errx(2, "mmap transhuge");
if (madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE))
err(2, "MADV_HUGEPAGE");
/* allocate transparent huge page */
*(volatile void **)ptr = ptr;
if (pread(pagemap_fd, ent, sizeof(ent),
(uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent))
err(2, "read pagemap");
if (PAGEMAP_PRESENT(ent[0]) && PAGEMAP_PRESENT(ent[1]) &&
PAGEMAP_PFN(ent[0]) + 1 == PAGEMAP_PFN(ent[1]) &&
!(PAGEMAP_PFN(ent[0]) & ((1 << (HPAGE_SHIFT - PAGE_SHIFT)) - 1)))
return PAGEMAP_PFN(ent[0]);
return -1;
}
static int ksm_merge_hugepages_time(int mapping, int prot, int timeout, size_t map_size)
{
void *map_ptr, *map_ptr_orig;
struct timespec start_time, end_time;
unsigned long scan_time_ns;
int pagemap_fd, n_normal_pages, n_huge_pages;
map_size *= MB;
size_t len = map_size;
len -= len % HPAGE_SIZE;
map_ptr_orig = mmap(NULL, len + HPAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE, -1, 0);
map_ptr = map_ptr_orig + HPAGE_SIZE - (uintptr_t)map_ptr_orig % HPAGE_SIZE;
if (map_ptr_orig == MAP_FAILED)
err(2, "initial mmap");
if (madvise(map_ptr, len + HPAGE_SIZE, MADV_HUGEPAGE))
err(2, "MADV_HUGEPAGE");
pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
if (pagemap_fd < 0)
err(2, "open pagemap");
n_normal_pages = 0;
n_huge_pages = 0;
for (void *p = map_ptr; p < map_ptr + len; p += HPAGE_SIZE) {
if (allocate_transhuge(p, pagemap_fd) < 0)
n_normal_pages++;
else
n_huge_pages++;
}
printf("Number of normal pages: %d\n", n_normal_pages);
printf("Number of huge pages: %d\n", n_huge_pages);
memset(map_ptr, '*', len);
if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
perror("clock_gettime");
goto err_out;
}
if (ksm_merge_pages(map_ptr, map_size, start_time, timeout))
goto err_out;
if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
perror("clock_gettime");
goto err_out;
}
scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
(end_time.tv_nsec - start_time.tv_nsec);
printf("Total size: %lu MiB\n", map_size / MB);
printf("Total time: %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,
scan_time_ns % NSEC_PER_SEC);
printf("Average speed: %.3f MiB/s\n", (map_size / MB) /
((double)scan_time_ns / NSEC_PER_SEC));
munmap(map_ptr_orig, len + HPAGE_SIZE);
return KSFT_PASS;
err_out:
printf("Not OK\n");
munmap(map_ptr_orig, len + HPAGE_SIZE);
return KSFT_FAIL;
}
static int ksm_merge_time(int mapping, int prot, int timeout, size_t map_size)
{
void *map_ptr;
@ -564,7 +676,7 @@ int main(int argc, char *argv[])
bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT;
long size_MB = 0;
while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPC")) != -1) {
while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPCH")) != -1) {
switch (opt) {
case 'a':
prot = str_to_prot(optarg);
@ -618,6 +730,9 @@ int main(int argc, char *argv[])
case 'P':
test_name = KSM_MERGE_TIME;
break;
case 'H':
test_name = KSM_MERGE_TIME_HUGE_PAGES;
break;
case 'C':
test_name = KSM_COW_TIME;
break;
@ -670,6 +785,14 @@ int main(int argc, char *argv[])
ret = ksm_merge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
size_MB);
break;
case KSM_MERGE_TIME_HUGE_PAGES:
if (size_MB == 0) {
printf("Option '-s' is required.\n");
return KSFT_FAIL;
}
ret = ksm_merge_hugepages_time(MAP_PRIVATE | MAP_ANONYMOUS, prot,
ksm_scan_limit_sec, size_MB);
break;
case KSM_COW_TIME:
ret = ksm_cow_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
page_size);