The patch titled
Subject: selftests/vm: dedup THP helpers
has been added to the -mm mm-unstable branch. Its filename is
selftests-vm-dedup-thp-helpers.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-vm-dedup-thp-helpers.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Zach O'Keefe" <zokeefe@xxxxxxxxxx>
Subject: selftests/vm: dedup THP helpers
Date: Thu, 22 Sep 2022 15:40:41 -0700
These files:
tools/testing/selftests/vm/vm_util.c
tools/testing/selftests/vm/khugepaged.c
Both contain logic to:
1) Determine hugepage size on current system
2) Read /proc/self/smaps to determine number of THPs at an address
Refactor selftests/vm/khugepaged.c to use the vm_util common helpers and
add it as a build dependency.
Since selftests/vm/khugepaged.c is the largest user of check_huge(),
change the signature of check_huge() to match selftests/vm/khugepaged.c's
useage: take an expected number of hugepages, and return a bool indicating
if the correct number of hugepages were found. Add a wrapper,
check_huge_anon(), in anticipation of checking smaps for file and shmem
hugepages.
Update existing callsites to use the new pattern / function.
Likewise, check_for_pattern() was duplicated, and it's a general enough
helper to include in vm_util helpers as well.
Link: https://lkml.kernel.org/r/20220907144521.3115321-6-zokeefe@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20220922224046.1143204-6-zokeefe@xxxxxxxxxx
Signed-off-by: Zach O'Keefe <zokeefe@xxxxxxxxxx>
Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx>
Cc: Chris Kennelly <ckennelly@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: James Houghton <jthoughton@xxxxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Rongwei Wang <rongwei.wang@xxxxxxxxxxxxxxxxx>
Cc: SeongJae Park <sj@xxxxxxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/tools/testing/selftests/vm/khugepaged.c~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/khugepaged.c
@@ -12,6 +12,8 @@
#include <sys/mman.h>
#include <sys/wait.h>
+#include "vm_util.h"
+
#ifndef MADV_PAGEOUT
#define MADV_PAGEOUT 21
#endif
@@ -352,64 +354,12 @@ static void save_settings(void)
signal(SIGQUIT, restore_settings);
}
-#define MAX_LINE_LENGTH 500
-
-static bool check_for_pattern(FILE *fp, char *pattern, char *buf)
-{
- while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) {
- if (!strncmp(buf, pattern, strlen(pattern)))
- return true;
- }
- return false;
-}
-
static bool check_huge(void *addr, int nr_hpages)
{
- bool thp = false;
- int ret;
- FILE *fp;
- char buffer[MAX_LINE_LENGTH];
- char addr_pattern[MAX_LINE_LENGTH];
-
- ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
- (unsigned long) addr);
- if (ret >= MAX_LINE_LENGTH) {
- printf("%s: Pattern is too long\n", __func__);
- exit(EXIT_FAILURE);
- }
-
-
- fp = fopen(PID_SMAPS, "r");
- if (!fp) {
- printf("%s: Failed to open file %s\n", __func__, PID_SMAPS);
- exit(EXIT_FAILURE);
- }
- if (!check_for_pattern(fp, addr_pattern, buffer))
- goto err_out;
-
- ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "AnonHugePages:%10ld kB",
- nr_hpages * (hpage_pmd_size >> 10));
- if (ret >= MAX_LINE_LENGTH) {
- printf("%s: Pattern is too long\n", __func__);
- exit(EXIT_FAILURE);
- }
- /*
- * Fetch the AnonHugePages: in the same block and check whether it got
- * the expected number of hugeepages next.
- */
- if (!check_for_pattern(fp, "AnonHugePages:", buffer))
- goto err_out;
-
- if (strncmp(buffer, addr_pattern, strlen(addr_pattern)))
- goto err_out;
-
- thp = true;
-err_out:
- fclose(fp);
- return thp;
+ return check_huge_anon(addr, nr_hpages, hpage_pmd_size);
}
-
+#define MAX_LINE_LENGTH 500
static bool check_swap(void *addr, unsigned long size)
{
bool swap = false;
@@ -431,7 +381,7 @@ static bool check_swap(void *addr, unsig
printf("%s: Failed to open file %s\n", __func__, PID_SMAPS);
exit(EXIT_FAILURE);
}
- if (!check_for_pattern(fp, addr_pattern, buffer))
+ if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
goto err_out;
ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "Swap:%19ld kB",
@@ -444,7 +394,7 @@ static bool check_swap(void *addr, unsig
* Fetch the Swap: in the same block and check whether it got
* the expected number of hugeepages next.
*/
- if (!check_for_pattern(fp, "Swap:", buffer))
+ if (!check_for_pattern(fp, "Swap:", buffer, sizeof(buffer)))
goto err_out;
if (strncmp(buffer, addr_pattern, strlen(addr_pattern)))
@@ -1066,7 +1016,7 @@ int main(int argc, const char **argv)
setbuf(stdout, NULL);
page_size = getpagesize();
- hpage_pmd_size = read_num("hpage_pmd_size");
+ hpage_pmd_size = read_pmd_pagesize();
hpage_pmd_nr = hpage_pmd_size / page_size;
default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1;
--- a/tools/testing/selftests/vm/Makefile~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/Makefile
@@ -95,6 +95,7 @@ TEST_FILES += va_128TBswitch.sh
include ../lib.mk
+$(OUTPUT)/khugepaged: vm_util.c
$(OUTPUT)/madv_populate: vm_util.c
$(OUTPUT)/soft-dirty: vm_util.c
$(OUTPUT)/split_huge_page_test: vm_util.c
--- a/tools/testing/selftests/vm/soft-dirty.c~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/soft-dirty.c
@@ -91,7 +91,7 @@ static void test_hugepage(int pagemap_fd
for (i = 0; i < hpage_len; i++)
map[i] = (char)i;
- if (check_huge(map)) {
+ if (check_huge_anon(map, 1, hpage_len)) {
ksft_test_result_pass("Test %s huge page allocation\n", __func__);
clear_softdirty();
--- a/tools/testing/selftests/vm/split_huge_page_test.c~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/split_huge_page_test.c
@@ -92,7 +92,6 @@ void split_pmd_thp(void)
{
char *one_page;
size_t len = 4 * pmd_pagesize;
- uint64_t thp_size;
size_t i;
one_page = memalign(pmd_pagesize, len);
@@ -107,8 +106,7 @@ void split_pmd_thp(void)
for (i = 0; i < len; i++)
one_page[i] = (char)i;
- thp_size = check_huge(one_page);
- if (!thp_size) {
+ if (!check_huge_anon(one_page, 1, pmd_pagesize)) {
printf("No THP is allocated\n");
exit(EXIT_FAILURE);
}
@@ -124,9 +122,8 @@ void split_pmd_thp(void)
}
- thp_size = check_huge(one_page);
- if (thp_size) {
- printf("Still %ld kB AnonHugePages not split\n", thp_size);
+ if (check_huge_anon(one_page, 0, pmd_pagesize)) {
+ printf("Still AnonHugePages not split\n");
exit(EXIT_FAILURE);
}
@@ -172,8 +169,7 @@ void split_pte_mapped_thp(void)
for (i = 0; i < len; i++)
one_page[i] = (char)i;
- thp_size = check_huge(one_page);
- if (!thp_size) {
+ if (!check_huge_anon(one_page, 1, pmd_pagesize)) {
printf("No THP is allocated\n");
exit(EXIT_FAILURE);
}
--- a/tools/testing/selftests/vm/vm_util.c~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/vm_util.c
@@ -64,9 +64,9 @@ void clear_softdirty(void)
ksft_exit_fail_msg("writing clear_refs failed\n");
}
-static bool check_for_pattern(FILE *fp, const char *pattern, char *buf)
+bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len)
{
- while (fgets(buf, MAX_LINE_LENGTH, fp) != NULL) {
+ while (fgets(buf, len, fp)) {
if (!strncmp(buf, pattern, strlen(pattern)))
return true;
}
@@ -94,9 +94,10 @@ uint64_t read_pmd_pagesize(void)
return strtoul(buf, NULL, 10);
}
-uint64_t check_huge(void *addr)
+bool __check_huge(void *addr, char *pattern, int nr_hpages,
+ uint64_t hpage_size)
{
- uint64_t thp = 0;
+ uint64_t thp = -1;
int ret;
FILE *fp;
char buffer[MAX_LINE_LENGTH];
@@ -111,20 +112,27 @@ uint64_t check_huge(void *addr)
if (!fp)
ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, SMAP_FILE_PATH);
- if (!check_for_pattern(fp, addr_pattern, buffer))
+ if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
goto err_out;
/*
- * Fetch the AnonHugePages: in the same block and check the number of
+ * Fetch the pattern in the same block and check the number of
* hugepages.
*/
- if (!check_for_pattern(fp, "AnonHugePages:", buffer))
+ if (!check_for_pattern(fp, pattern, buffer, sizeof(buffer)))
goto err_out;
- if (sscanf(buffer, "AnonHugePages:%10ld kB", &thp) != 1)
+ snprintf(addr_pattern, MAX_LINE_LENGTH, "%s%%9ld kB", pattern);
+
+ if (sscanf(buffer, addr_pattern, &thp) != 1)
ksft_exit_fail_msg("Reading smap error\n");
err_out:
fclose(fp);
- return thp;
+ return thp == (nr_hpages * (hpage_size >> 10));
+}
+
+bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size)
+{
+ return __check_huge(addr, "AnonHugePages: ", nr_hpages, hpage_size);
}
--- a/tools/testing/selftests/vm/vm_util.h~selftests-vm-dedup-thp-helpers
+++ a/tools/testing/selftests/vm/vm_util.h
@@ -7,5 +7,6 @@ bool pagemap_is_softdirty(int fd, char *
bool pagemap_is_swapped(int fd, char *start);
bool pagemap_range_some_swapped(int fd, char *start, size_t len);
void clear_softdirty(void);
+bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len);
uint64_t read_pmd_pagesize(void);
-uint64_t check_huge(void *addr);
+bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size);
_
Patches currently in -mm which might be from zokeefe@xxxxxxxxxx are
mm-khugepaged-check-compound_order-in-collapse_pte_mapped_thp.patch
mm-madvise-madv_collapse-return-eagain-when-page-cannot-be-isolated.patch
selftests-vm-retry-on-eagain-for-madv_collapse-selftest.patch
mm-shmem-add-flag-to-enforce-shmem-thp-in-hugepage_vma_check.patch
mm-khugepaged-attempt-to-map-file-shmem-backed-pte-mapped-thps-by-pmds.patch
mm-madvise-add-file-and-shmem-support-to-madv_collapse.patch
mm-khugepaged-add-tracepoint-to-hpage_collapse_scan_file.patch
selftests-vm-dedup-thp-helpers.patch
selftests-vm-modularize-thp-collapse-memory-operations.patch
selftests-vm-add-thp-collapse-file-and-tmpfs-testing.patch
selftests-vm-add-thp-collapse-shmem-testing.patch
selftests-vm-add-file-shmem-madv_collapse-selftest-for-cleared-pmd.patch
selftests-vm-add-selftest-for-madv_collapse-of-uffd-minor-memory.patch
