The patch titled
Subject: selftests/mm: support multi-size THP interface in thp_settings
has been added to the -mm mm-unstable branch. Its filename is
selftests-mm-support-multi-size-thp-interface-in-thp_settings.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-support-multi-size-thp-interface-in-thp_settings.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: support multi-size THP interface in thp_settings
Date: Thu, 7 Dec 2023 16:12:08 +0000
Save and restore the new per-size hugepage enabled setting, if available
on the running kernel.
Since the number of per-size directories is not fixed, solve this as
simply as possible by catering for a maximum number in the thp_settings
struct (20). Each array index is the order. The value of THP_NEVER is
changed to 0 so that all of these new settings default to THP_NEVER and
the user only needs to fill in the ones they want to enable.
Link: https://lkml.kernel.org/r/20231207161211.2374093-8-ryan.roberts@xxxxxxx
Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Tested-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Tested-by: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Barry Song <v-songbaohua@xxxxxxxx>
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: 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/khugepaged.c | 3 +
tools/testing/selftests/mm/thp_settings.c | 55 +++++++++++++++++++-
tools/testing/selftests/mm/thp_settings.h | 11 +++-
3 files changed, 67 insertions(+), 2 deletions(-)
--- a/tools/testing/selftests/mm/khugepaged.c~selftests-mm-support-multi-size-thp-interface-in-thp_settings
+++ a/tools/testing/selftests/mm/khugepaged.c
@@ -1141,6 +1141,7 @@ static void parse_test_type(int argc, co
int main(int argc, const char **argv)
{
+ int hpage_pmd_order;
struct thp_settings default_settings = {
.thp_enabled = THP_MADVISE,
.thp_defrag = THP_DEFRAG_ALWAYS,
@@ -1175,11 +1176,13 @@ int main(int argc, const char **argv)
exit(EXIT_FAILURE);
}
hpage_pmd_nr = hpage_pmd_size / page_size;
+ hpage_pmd_order = __builtin_ctz(hpage_pmd_nr);
default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1;
default_settings.khugepaged.max_ptes_swap = hpage_pmd_nr / 8;
default_settings.khugepaged.max_ptes_shared = hpage_pmd_nr / 2;
default_settings.khugepaged.pages_to_scan = hpage_pmd_nr * 8;
+ default_settings.hugepages[hpage_pmd_order].enabled = THP_INHERIT;
save_settings();
thp_push_settings(&default_settings);
--- a/tools/testing/selftests/mm/thp_settings.c~selftests-mm-support-multi-size-thp-interface-in-thp_settings
+++ a/tools/testing/selftests/mm/thp_settings.c
@@ -16,9 +16,10 @@ static struct thp_settings saved_setting
static char dev_queue_read_ahead_path[PATH_MAX];
static const char * const thp_enabled_strings[] = {
+ "never",
"always",
+ "inherit",
"madvise",
- "never",
NULL
};
@@ -198,6 +199,10 @@ void thp_write_num(const char *name, uns
void thp_read_settings(struct thp_settings *settings)
{
+ unsigned long orders = thp_supported_orders();
+ char path[PATH_MAX];
+ int i;
+
*settings = (struct thp_settings) {
.thp_enabled = thp_read_string("enabled", thp_enabled_strings),
.thp_defrag = thp_read_string("defrag", thp_defrag_strings),
@@ -218,11 +223,26 @@ void thp_read_settings(struct thp_settin
};
if (dev_queue_read_ahead_path[0])
settings->read_ahead_kb = read_num(dev_queue_read_ahead_path);
+
+ for (i = 0; i < NR_ORDERS; i++) {
+ if (!((1 << i) & orders)) {
+ settings->hugepages[i].enabled = THP_NEVER;
+ continue;
+ }
+ snprintf(path, PATH_MAX, "hugepages-%ukB/enabled",
+ (getpagesize() >> 10) << i);
+ settings->hugepages[i].enabled =
+ thp_read_string(path, thp_enabled_strings);
+ }
}
void thp_write_settings(struct thp_settings *settings)
{
struct khugepaged_settings *khugepaged = &settings->khugepaged;
+ unsigned long orders = thp_supported_orders();
+ char path[PATH_MAX];
+ int enabled;
+ int i;
thp_write_string("enabled", thp_enabled_strings[settings->thp_enabled]);
thp_write_string("defrag", thp_defrag_strings[settings->thp_defrag]);
@@ -242,6 +262,15 @@ void thp_write_settings(struct thp_setti
if (dev_queue_read_ahead_path[0])
write_num(dev_queue_read_ahead_path, settings->read_ahead_kb);
+
+ for (i = 0; i < NR_ORDERS; i++) {
+ if (!((1 << i) & orders))
+ continue;
+ snprintf(path, PATH_MAX, "hugepages-%ukB/enabled",
+ (getpagesize() >> 10) << i);
+ enabled = settings->hugepages[i].enabled;
+ thp_write_string(path, thp_enabled_strings[enabled]);
+ }
}
struct thp_settings *thp_current_settings(void)
@@ -294,3 +323,27 @@ void thp_set_read_ahead_path(char *path)
sizeof(dev_queue_read_ahead_path));
dev_queue_read_ahead_path[sizeof(dev_queue_read_ahead_path) - 1] = '\0';
}
+
+unsigned long thp_supported_orders(void)
+{
+ unsigned long orders = 0;
+ char path[PATH_MAX];
+ char buf[256];
+ int ret;
+ int i;
+
+ for (i = 0; i < NR_ORDERS; i++) {
+ ret = snprintf(path, PATH_MAX, THP_SYSFS "hugepages-%ukB/enabled",
+ (getpagesize() >> 10) << i);
+ if (ret >= PATH_MAX) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+ ret = read_file(path, buf, sizeof(buf));
+ if (ret)
+ orders |= 1UL << i;
+ }
+
+ return orders;
+}
--- a/tools/testing/selftests/mm/thp_settings.h~selftests-mm-support-multi-size-thp-interface-in-thp_settings
+++ a/tools/testing/selftests/mm/thp_settings.h
@@ -7,9 +7,10 @@
#include <stdint.h>
enum thp_enabled {
+ THP_NEVER,
THP_ALWAYS,
+ THP_INHERIT,
THP_MADVISE,
- THP_NEVER,
};
enum thp_defrag {
@@ -29,6 +30,12 @@ enum shmem_enabled {
SHMEM_FORCE,
};
+#define NR_ORDERS 20
+
+struct hugepages_settings {
+ enum thp_enabled enabled;
+};
+
struct khugepaged_settings {
bool defrag;
unsigned int alloc_sleep_millisecs;
@@ -46,6 +53,7 @@ struct thp_settings {
bool use_zero_page;
struct khugepaged_settings khugepaged;
unsigned long read_ahead_kb;
+ struct hugepages_settings hugepages[NR_ORDERS];
};
int read_file(const char *path, char *buf, size_t buflen);
@@ -67,5 +75,6 @@ void thp_restore_settings(void);
void thp_save_settings(void);
void thp_set_read_ahead_path(char *path);
+unsigned long thp_supported_orders(void);
#endif /* __THP_SETTINGS_H__ */
_
Patches currently in -mm which might be from ryan.roberts@xxxxxxx are
mm-readahead-do-not-allow-order-1-folio.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-introduce-multi-size-thp-sysfs-interface.patch
mm-thp-support-allocation-of-anonymous-multi-size-thp.patch
selftests-mm-kugepaged-restore-thp-settings-at-exit.patch
selftests-mm-factor-out-thp-settings-management.patch
selftests-mm-support-multi-size-thp-interface-in-thp_settings.patch
selftests-mm-khugepaged-enlighten-for-multi-size-thp.patch
selftests-mm-cow-generalize-do_run_with_thp-helper.patch
selftests-mm-cow-add-tests-for-anonymous-multi-size-thp.patch
