The patch titled
Subject: selftests/mm/cow: generalize do_run_with_thp() helper
has been added to the -mm mm-unstable branch. Its filename is
selftests-mm-cow-generalize-do_run_with_thp-helper.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-cow-generalize-do_run_with_thp-helper.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: Ryan Roberts <ryan.roberts@xxxxxxx>
Subject: selftests/mm/cow: generalize do_run_with_thp() helper
Date: Fri, 29 Sep 2023 12:44:19 +0100
do_run_with_thp() prepares (PMD-sized) THP memory into different states
before running tests. With the introduction of THP orders that are
smaller than PMD_ORDER, we would like to reuse this logic to also test
those smaller orders. So let's add a size parameter which tells the
function what size THP it should operate on.
No functional change intended here, but a separate commit will add new
tests for smaller order THP, where available.
Link: https://lkml.kernel.org/r/20230929114421.3761121-9-ryan.roberts@xxxxxxx
Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Itaru Kitayama <itaru.kitayama@xxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Yin Fengwei <fengwei.yin@xxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/mm/cow.c | 151 ++++++++++++++++-------------
1 file changed, 84 insertions(+), 67 deletions(-)
--- a/tools/testing/selftests/mm/cow.c~selftests-mm-cow-generalize-do_run_with_thp-helper
+++ a/tools/testing/selftests/mm/cow.c
@@ -32,7 +32,7 @@
static size_t pagesize;
static int pagemap_fd;
-static size_t thpsize;
+static size_t pmdsize;
static int nr_hugetlbsizes;
static size_t hugetlbsizes[10];
static int gup_fd;
@@ -734,14 +734,14 @@ enum thp_run {
THP_RUN_PARTIAL_SHARED,
};
-static void do_run_with_thp(test_fn fn, enum thp_run thp_run)
+static void do_run_with_thp(test_fn fn, enum thp_run thp_run, size_t size)
{
char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED;
- size_t size, mmap_size, mremap_size;
+ size_t mmap_size, mremap_size;
int ret;
- /* For alignment purposes, we need twice the thp size. */
- mmap_size = 2 * thpsize;
+ /* For alignment purposes, we need twice the requested size. */
+ mmap_size = 2 * size;
mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (mmap_mem == MAP_FAILED) {
@@ -749,36 +749,40 @@ static void do_run_with_thp(test_fn fn,
return;
}
- /* We need a THP-aligned memory area. */
- mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1));
+ /* We need to naturally align the memory area. */
+ mem = (char *)(((uintptr_t)mmap_mem + size) & ~(size - 1));
- ret = madvise(mem, thpsize, MADV_HUGEPAGE);
+ ret = madvise(mem, size, MADV_HUGEPAGE);
if (ret) {
ksft_test_result_fail("MADV_HUGEPAGE failed\n");
goto munmap;
}
/*
- * Try to populate a THP. Touch the first sub-page and test if we get
- * another sub-page populated automatically.
+ * Try to populate a THP. Touch the first sub-page and test if
+ * we get the last sub-page populated automatically.
*/
mem[0] = 0;
- if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) {
+ if (!pagemap_is_populated(pagemap_fd, mem + size - pagesize)) {
ksft_test_result_skip("Did not get a THP populated\n");
goto munmap;
}
- memset(mem, 0, thpsize);
+ memset(mem, 0, size);
- size = thpsize;
switch (thp_run) {
case THP_RUN_PMD:
case THP_RUN_PMD_SWAPOUT:
+ if (size != pmdsize) {
+ ksft_test_result_fail("test bug: can't PMD-map size\n");
+ goto munmap;
+ }
break;
case THP_RUN_PTE:
case THP_RUN_PTE_SWAPOUT:
/*
* Trigger PTE-mapping the THP by temporarily mapping a single
- * subpage R/O.
+ * subpage R/O. This is a noop if the THP is not pmdsize (and
+ * therefore already PTE-mapped).
*/
ret = mprotect(mem + pagesize, pagesize, PROT_READ);
if (ret) {
@@ -797,7 +801,7 @@ static void do_run_with_thp(test_fn fn,
* Discard all but a single subpage of that PTE-mapped THP. What
* remains is a single PTE mapping a single subpage.
*/
- ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED);
+ ret = madvise(mem + pagesize, size - pagesize, MADV_DONTNEED);
if (ret) {
ksft_test_result_fail("MADV_DONTNEED failed\n");
goto munmap;
@@ -809,7 +813,7 @@ static void do_run_with_thp(test_fn fn,
* Remap half of the THP. We need some new memory location
* for that.
*/
- mremap_size = thpsize / 2;
+ mremap_size = size / 2;
mremap_mem = mmap(NULL, mremap_size, PROT_NONE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (mem == MAP_FAILED) {
@@ -830,7 +834,7 @@ static void do_run_with_thp(test_fn fn,
* child. This will result in some parts of the THP never
* have been shared.
*/
- ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK);
+ ret = madvise(mem + pagesize, size - pagesize, MADV_DONTFORK);
if (ret) {
ksft_test_result_fail("MADV_DONTFORK failed\n");
goto munmap;
@@ -844,7 +848,7 @@ static void do_run_with_thp(test_fn fn,
}
wait(&ret);
/* Allow for sharing all pages again. */
- ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK);
+ ret = madvise(mem + pagesize, size - pagesize, MADV_DOFORK);
if (ret) {
ksft_test_result_fail("MADV_DOFORK failed\n");
goto munmap;
@@ -875,52 +879,65 @@ munmap:
munmap(mremap_mem, mremap_size);
}
-static void run_with_thp(test_fn fn, const char *desc)
+static int sz2ord(size_t size)
+{
+ return __builtin_ctzll(size / pagesize);
+}
+
+static void run_with_thp(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PMD);
+ ksft_print_msg("[RUN] %s ... with order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PMD, size);
}
-static void run_with_thp_swap(test_fn fn, const char *desc)
+static void run_with_thp_swap(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT);
+ ksft_print_msg("[RUN] %s ... with swapped-out order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT, size);
}
-static void run_with_pte_mapped_thp(test_fn fn, const char *desc)
+static void run_with_pte_mapped_thp(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PTE);
+ ksft_print_msg("[RUN] %s ... with PTE-mapped order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PTE, size);
}
-static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc)
+static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT);
+ ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT, size);
}
-static void run_with_single_pte_of_thp(test_fn fn, const char *desc)
+static void run_with_single_pte_of_thp(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc);
- do_run_with_thp(fn, THP_RUN_SINGLE_PTE);
+ ksft_print_msg("[RUN] %s ... with single PTE of order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_SINGLE_PTE, size);
}
-static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc)
+static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc);
- do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT);
+ ksft_print_msg("[RUN] %s ... with single PTE of swapped-out order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT, size);
}
-static void run_with_partial_mremap_thp(test_fn fn, const char *desc)
+static void run_with_partial_mremap_thp(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP);
+ ksft_print_msg("[RUN] %s ... with partially mremap()'ed order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP, size);
}
-static void run_with_partial_shared_thp(test_fn fn, const char *desc)
+static void run_with_partial_shared_thp(test_fn fn, const char *desc, size_t size)
{
- ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc);
- do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED);
+ ksft_print_msg("[RUN] %s ... with partially shared order-%d THP\n",
+ desc, sz2ord(size));
+ do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED, size);
}
static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize)
@@ -1091,15 +1108,15 @@ static void run_anon_test_case(struct te
run_with_base_page(test_case->fn, test_case->desc);
run_with_base_page_swap(test_case->fn, test_case->desc);
- if (thpsize) {
- run_with_thp(test_case->fn, test_case->desc);
- run_with_thp_swap(test_case->fn, test_case->desc);
- run_with_pte_mapped_thp(test_case->fn, test_case->desc);
- run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc);
- run_with_single_pte_of_thp(test_case->fn, test_case->desc);
- run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc);
- run_with_partial_mremap_thp(test_case->fn, test_case->desc);
- run_with_partial_shared_thp(test_case->fn, test_case->desc);
+ if (pmdsize) {
+ run_with_thp(test_case->fn, test_case->desc, pmdsize);
+ run_with_thp_swap(test_case->fn, test_case->desc, pmdsize);
+ run_with_pte_mapped_thp(test_case->fn, test_case->desc, pmdsize);
+ run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc, pmdsize);
+ run_with_single_pte_of_thp(test_case->fn, test_case->desc, pmdsize);
+ run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc, pmdsize);
+ run_with_partial_mremap_thp(test_case->fn, test_case->desc, pmdsize);
+ run_with_partial_shared_thp(test_case->fn, test_case->desc, pmdsize);
}
for (i = 0; i < nr_hugetlbsizes; i++)
run_with_hugetlb(test_case->fn, test_case->desc,
@@ -1120,7 +1137,7 @@ static int tests_per_anon_test_case(void
{
int tests = 2 + nr_hugetlbsizes;
- if (thpsize)
+ if (pmdsize)
tests += 8;
return tests;
}
@@ -1329,7 +1346,7 @@ static void run_anon_thp_test_cases(void
{
int i;
- if (!thpsize)
+ if (!pmdsize)
return;
ksft_print_msg("[INFO] Anonymous THP tests\n");
@@ -1338,13 +1355,13 @@ static void run_anon_thp_test_cases(void
struct test_case const *test_case = &anon_thp_test_cases[i];
ksft_print_msg("[RUN] %s\n", test_case->desc);
- do_run_with_thp(test_case->fn, THP_RUN_PMD);
+ do_run_with_thp(test_case->fn, THP_RUN_PMD, pmdsize);
}
}
static int tests_per_anon_thp_test_case(void)
{
- return thpsize ? 1 : 0;
+ return pmdsize ? 1 : 0;
}
typedef void (*non_anon_test_fn)(char *mem, const char *smem, size_t size);
@@ -1419,7 +1436,7 @@ static void run_with_huge_zeropage(non_a
}
/* For alignment purposes, we need twice the thp size. */
- mmap_size = 2 * thpsize;
+ mmap_size = 2 * pmdsize;
mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (mmap_mem == MAP_FAILED) {
@@ -1434,11 +1451,11 @@ static void run_with_huge_zeropage(non_a
}
/* We need a THP-aligned memory area. */
- mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1));
- smem = (char *)(((uintptr_t)mmap_smem + thpsize) & ~(thpsize - 1));
+ mem = (char *)(((uintptr_t)mmap_mem + pmdsize) & ~(pmdsize - 1));
+ smem = (char *)(((uintptr_t)mmap_smem + pmdsize) & ~(pmdsize - 1));
- ret = madvise(mem, thpsize, MADV_HUGEPAGE);
- ret |= madvise(smem, thpsize, MADV_HUGEPAGE);
+ ret = madvise(mem, pmdsize, MADV_HUGEPAGE);
+ ret |= madvise(smem, pmdsize, MADV_HUGEPAGE);
if (ret) {
ksft_test_result_fail("MADV_HUGEPAGE failed\n");
goto munmap;
@@ -1457,7 +1474,7 @@ static void run_with_huge_zeropage(non_a
goto munmap;
}
- fn(mem, smem, thpsize);
+ fn(mem, smem, pmdsize);
munmap:
munmap(mmap_mem, mmap_size);
if (mmap_smem != MAP_FAILED)
@@ -1650,7 +1667,7 @@ static void run_non_anon_test_case(struc
run_with_zeropage(test_case->fn, test_case->desc);
run_with_memfd(test_case->fn, test_case->desc);
run_with_tmpfile(test_case->fn, test_case->desc);
- if (thpsize)
+ if (pmdsize)
run_with_huge_zeropage(test_case->fn, test_case->desc);
for (i = 0; i < nr_hugetlbsizes; i++)
run_with_memfd_hugetlb(test_case->fn, test_case->desc,
@@ -1671,7 +1688,7 @@ static int tests_per_non_anon_test_case(
{
int tests = 3 + nr_hugetlbsizes;
- if (thpsize)
+ if (pmdsize)
tests += 1;
return tests;
}
@@ -1681,10 +1698,10 @@ int main(int argc, char **argv)
int err;
pagesize = getpagesize();
- thpsize = read_pmd_pagesize();
- if (thpsize)
- ksft_print_msg("[INFO] detected THP size: %zu KiB\n",
- thpsize / 1024);
+ pmdsize = read_pmd_pagesize();
+ if (pmdsize)
+ ksft_print_msg("[INFO] detected PMD-mapped THP size: %zu KiB\n",
+ pmdsize / 1024);
nr_hugetlbsizes = detect_hugetlb_page_sizes(hugetlbsizes,
ARRAY_SIZE(hugetlbsizes));
detect_huge_zeropage();
_
Patches currently in -mm which might be from ryan.roberts@xxxxxxx are
mm-hugetlb-add-huge-page-size-param-to-set_huge_pte_at.patch
arm64-hugetlb-fix-set_huge_pte_at-to-work-with-all-swap-entries.patch
mm-allow-deferred-splitting-of-arbitrary-anon-large-folios.patch
mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.patch
mm-thp-account-pte-mapped-anonymous-thp-usage.patch
mm-thp-introduce-anon_orders-and-anon_always_mask-sysfs-files.patch
mm-thp-extend-thp-to-allocate-anonymous-large-folios.patch
mm-thp-add-recommend-option-for-anon_orders.patch
arm64-mm-override-arch_wants_pte_order.patch
selftests-mm-cow-generalize-do_run_with_thp-helper.patch
selftests-mm-cow-add-tests-for-small-order-anon-thp.patch
