Soft offlining a HugeTLB page reduces the HugeTLB page pool.
Commit 56374430c5dfc ("mm/memory-failure: userspace controls soft-offlining pages")
introduced the following sysctl interface to control soft offline:
/proc/sys/vm/enable_soft_offline
The interface does not distinguish between page types:
0 - Soft offline is disabled
1 - Soft offline is enabled
Convert enable_soft_offline to a bitmask and support disabling soft
offline for HugeTLB pages:
Bits:
0 - Enable soft offline
1 - Disable soft offline for HugeTLB pages
Supported values:
0 - Soft offline is disabled
1 - Soft offline is enabled
3 - Soft offline is enabled (disabled for HugeTLB pages)
Existing behavior is preserved.
Update documentation and HugeTLB soft offline self tests.
Reported-by: Shawn Fan <shawn.fan(a)intel.com>
Suggested-by: Tony Luck <tony.luck(a)intel.com>
Signed-off-by: Kyle Meyer <kyle.meyer(a)hpe.com>
---
Tony's patch:
* https://lore.kernel.org/all/20250904155720.22149-1-tony.luck@intel.com
v1:
* https://lore.kernel.org/all/aMGkAI3zKlVsO0S2@hpe.com
v1 -> v2:
* Make the interface extensible, as suggested by David.
* Preserve existing behavior, as suggested by Jiaqi and David.
Why clear errno in self tests?
madvise() does not set errno when it's successful and errno is set by madvise()
during test_soft_offline_common(3) causing test_soft_offline_common(1) to fail:
# Test soft-offline when enabled_soft_offline=1
# Hugepagesize is 1048576kB
# enable_soft_offline => 1
# Before MADV_SOFT_OFFLINE nr_hugepages=7
# Allocated 0x80000000 bytes of hugetlb pages
# MADV_SOFT_OFFLINE 0x7fd600000000 ret=0, errno=95
# MADV_SOFT_OFFLINE should ret 0
# After MADV_SOFT_OFFLINE nr_hugepages=6
not ok 2 Test soft-offline when enabled_soft_offline=1
---
.../ABI/testing/sysfs-memory-page-offline | 3 ++
Documentation/admin-guide/sysctl/vm.rst | 28 ++++++++++++++++---
mm/memory-failure.c | 17 +++++++++--
.../selftests/mm/hugetlb-soft-offline.c | 19 ++++++++++---
4 files changed, 56 insertions(+), 11 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-memory-page-offline b/Documentation/ABI/testing/sysfs-memory-page-offline
index 00f4e35f916f..d3f05ed6605e 100644
--- a/Documentation/ABI/testing/sysfs-memory-page-offline
+++ b/Documentation/ABI/testing/sysfs-memory-page-offline
@@ -20,6 +20,9 @@ Description:
number, or a error when the offlining failed. Reading
the file is not allowed.
+ Soft-offline can be controlled via sysctl, see:
+ Documentation/admin-guide/sysctl/vm.rst
+
What: /sys/devices/system/memory/hard_offline_page
Date: Sep 2009
KernelVersion: 2.6.33
diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst
index 4d71211fdad8..ace73480eb9d 100644
--- a/Documentation/admin-guide/sysctl/vm.rst
+++ b/Documentation/admin-guide/sysctl/vm.rst
@@ -309,19 +309,39 @@ physical memory) vs performance / capacity implications in transparent and
HugeTLB cases.
For all architectures, enable_soft_offline controls whether to soft offline
-memory pages. When set to 1, kernel attempts to soft offline the pages
-whenever it thinks needed. When set to 0, kernel returns EOPNOTSUPP to
-the request to soft offline the pages. Its default value is 1.
+memory pages.
+
+enable_soft_offline is a bitmask:
+
+Bits::
+
+ 0 - Enable soft offline
+ 1 - Disable soft offline for HugeTLB pages
+
+Supported values::
+
+ 0 - Soft offline is disabled
+ 1 - Soft offline is enabled
+ 3 - Soft offline is enabled (disabled for HugeTLB pages)
+
+The default value is 1.
+
+If soft offline is disabled for the requested page type, EOPNOTSUPP is returned.
It is worth mentioning that after setting enable_soft_offline to 0, the
following requests to soft offline pages will not be performed:
+- Request to soft offline from sysfs (soft_offline_page).
+
- Request to soft offline pages from RAS Correctable Errors Collector.
-- On ARM, the request to soft offline pages from GHES driver.
+- On ARM and X86, the request to soft offline pages from GHES driver.
- On PARISC, the request to soft offline pages from Page Deallocation Table.
+Note:
+ Soft offlining a HugeTLB page reduces the HugeTLB page pool.
+
extfrag_threshold
=================
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index fc30ca4804bf..0ad9ae11d9e8 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -64,11 +64,14 @@
#include "internal.h"
#include "ras/ras_event.h"
+#define SOFT_OFFLINE_ENABLED BIT(0)
+#define SOFT_OFFLINE_SKIP_HUGETLB BIT(1)
+
static int sysctl_memory_failure_early_kill __read_mostly;
static int sysctl_memory_failure_recovery __read_mostly = 1;
-static int sysctl_enable_soft_offline __read_mostly = 1;
+static int sysctl_enable_soft_offline __read_mostly = SOFT_OFFLINE_ENABLED;
atomic_long_t num_poisoned_pages __read_mostly = ATOMIC_LONG_INIT(0);
@@ -150,7 +153,7 @@ static const struct ctl_table memory_failure_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_ZERO,
- .extra2 = SYSCTL_ONE,
+ .extra2 = SYSCTL_THREE,
}
};
@@ -2799,12 +2802,20 @@ int soft_offline_page(unsigned long pfn, int flags)
return -EIO;
}
- if (!sysctl_enable_soft_offline) {
+ if (!(sysctl_enable_soft_offline & SOFT_OFFLINE_ENABLED)) {
pr_info_once("disabled by /proc/sys/vm/enable_soft_offline\n");
put_ref_page(pfn, flags);
return -EOPNOTSUPP;
}
+ if (sysctl_enable_soft_offline & SOFT_OFFLINE_SKIP_HUGETLB) {
+ if (folio_test_hugetlb(pfn_folio(pfn))) {
+ pr_info_once("disabled for HugeTLB pages by /proc/sys/vm/enable_soft_offline\n");
+ put_ref_page(pfn, flags);
+ return -EOPNOTSUPP;
+ }
+ }
+
mutex_lock(&mf_mutex);
if (PageHWPoison(page)) {
diff --git a/tools/testing/selftests/mm/hugetlb-soft-offline.c b/tools/testing/selftests/mm/hugetlb-soft-offline.c
index f086f0e04756..b87c8778cadf 100644
--- a/tools/testing/selftests/mm/hugetlb-soft-offline.c
+++ b/tools/testing/selftests/mm/hugetlb-soft-offline.c
@@ -5,6 +5,8 @@
* offlining failed with EOPNOTSUPP.
* - if enable_soft_offline = 1, a hugepage should be dissolved and
* nr_hugepages/free_hugepages should be reduced by 1.
+ * - if enable_soft_offline = 3, hugepages should stay intact and soft
+ * offlining failed with EOPNOTSUPP.
*
* Before running, make sure more than 2 hugepages of default_hugepagesz
* are allocated. For example, if /proc/meminfo/Hugepagesize is 2048kB:
@@ -32,6 +34,9 @@
#define EPREFIX " !!! "
+#define SOFT_OFFLINE_ENABLED (1 << 0)
+#define SOFT_OFFLINE_SKIP_HUGETLB (1 << 1)
+
static int do_soft_offline(int fd, size_t len, int expect_errno)
{
char *filemap = NULL;
@@ -56,6 +61,7 @@ static int do_soft_offline(int fd, size_t len, int expect_errno)
ksft_print_msg("Allocated %#lx bytes of hugetlb pages\n", len);
hwp_addr = filemap + len / 2;
+ errno = 0;
ret = madvise(hwp_addr, pagesize, MADV_SOFT_OFFLINE);
ksft_print_msg("MADV_SOFT_OFFLINE %p ret=%d, errno=%d\n",
hwp_addr, ret, errno);
@@ -83,7 +89,7 @@ static int set_enable_soft_offline(int value)
char cmd[256] = {0};
FILE *cmdfile = NULL;
- if (value != 0 && value != 1)
+ if (value < 0 || value > 3)
return -EINVAL;
sprintf(cmd, "echo %d > /proc/sys/vm/enable_soft_offline", value);
@@ -155,13 +161,17 @@ static int create_hugetlbfs_file(struct statfs *file_stat)
static void test_soft_offline_common(int enable_soft_offline)
{
int fd;
- int expect_errno = enable_soft_offline ? 0 : EOPNOTSUPP;
+ int expect_errno = 0;
struct statfs file_stat;
unsigned long hugepagesize_kb = 0;
unsigned long nr_hugepages_before = 0;
unsigned long nr_hugepages_after = 0;
int ret;
+ if (!(enable_soft_offline & SOFT_OFFLINE_ENABLED) ||
+ (enable_soft_offline & SOFT_OFFLINE_SKIP_HUGETLB))
+ expect_errno = EOPNOTSUPP;
+
ksft_print_msg("Test soft-offline when enabled_soft_offline=%d\n",
enable_soft_offline);
@@ -198,7 +208,7 @@ static void test_soft_offline_common(int enable_soft_offline)
// No need for the hugetlbfs file from now on.
close(fd);
- if (enable_soft_offline) {
+ if (expect_errno == 0) {
if (nr_hugepages_before != nr_hugepages_after + 1) {
ksft_test_result_fail("MADV_SOFT_OFFLINE should reduced 1 hugepage\n");
return;
@@ -219,8 +229,9 @@ static void test_soft_offline_common(int enable_soft_offline)
int main(int argc, char **argv)
{
ksft_print_header();
- ksft_set_plan(2);
+ ksft_set_plan(3);
+ test_soft_offline_common(3);
test_soft_offline_common(1);
test_soft_offline_common(0);
--
2.51.0
With the current Makefile, if the user tries something like
make TARGETS="bpf mm"
only mm is run and bpf is skipped, which is not intentional.
`bpf` and `sched_ext` are always filtered out even when TARGETS is set
explicitly due to how SKIP_TARGETS is implemented.
This default skip exists because these tests require newer LLVM/Clang
versions that may not be available on all systems.
Fix the SKIP_TARGETS logic so that bpf and sched_ext remain
skipped when TARGETS is taken from the Makefile but are included when
the user specifies them explicitly.
Signed-off-by: I Viswanath <viswanathiyyappan(a)gmail.com>
---
make --silent summary=1 TARGETS="bpf size" kselftest
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/bpf'
Auto-detecting system features:
... llvm: [ OFF ]
Makefile:127: tools/build/Makefile.feature: No such file or directory
make[4]: *** No rule to make target 'tools/build/Makefile.feature'. Stop.
make[3]: *** [Makefile:344: /home/user/kernel-dev/linux-next/tools/testing/selftests/bpf/tools/sbin/bpftool] Error 2
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/bpf'
make[3]: Nothing to be done for 'all'.
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/bpf'
Auto-detecting system features:
... llvm: [ OFF ]
Makefile:127: tools/build/Makefile.feature: No such file or directory
make[4]: *** No rule to make target 'tools/build/Makefile.feature'. Stop.
make[3]: *** [Makefile:344: /home/user/kernel-dev/linux-next/tools/testing/selftests/bpf/tools/sbin/bpftool] Error 2
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/bpf'
TAP version 13
1..1
# selftests: size: get_size
ok 1 selftests: size: get_size
make --silent summary=1 kselftest (bpf is between arm64 and breakpoints in TARGETS)
make[3]: Nothing to be done for 'all'.
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/alsa'
make[3]: Nothing to be done for 'all'.
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/alsa'
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/amd-pstate'
make[3]: Nothing to be done for 'all'.
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/amd-pstate'
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/arm64'
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/arm64'
make[3]: Entering directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/breakpoints'
make[3]: Nothing to be done for 'all'.
make[3]: Leaving directory '/home/user/kernel-dev/linux-next/tools/testing/selftests/breakpoints'
make[3]: Nothing to be done for 'all'.
tools/testing/selftests/Makefile | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index babed7b1c2d1..c6cedb09c372 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -145,7 +145,10 @@ endif
# User can optionally provide a TARGETS skiplist. By default we skip
# targets using BPF since it has cutting edge build time dependencies
# which require more effort to install.
-SKIP_TARGETS ?= bpf sched_ext
+ifeq ($(origin TARGETS), file)
+ SKIP_TARGETS ?= bpf sched_ext
+endif
+
ifneq ($(SKIP_TARGETS),)
TMP := $(filter-out $(SKIP_TARGETS), $(TARGETS))
override TARGETS := $(TMP)
--
2.47.3
Now that the 'flags' attribute is used, it seems interesting to add one
flag for 'server-side', a boolean value.
Here are a few patches related to the 'server-side' attribute:
- Patch 1: only announce this attribute on the server side.
- Patch 2: announce the 'server-side' flag when this is the case.
- Patch 3: deprecate the 'server-side' attribute.
- Patch 4: use the 'server-side' flag in the selftests.
- Patches 5, 6: small cleanups when working on code around.
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
---
Matthieu Baerts (NGI0) (6):
mptcp: pm: netlink: only add server-side attr when true
mptcp: pm: netlink: announce server-side flag
mptcp: pm: netlink: deprecate server-side attribute
selftests: mptcp: pm: get server-side flag
mptcp: use _BITUL() instead of (1 << x)
mptcp: remove unused returned value of check_data_fin
Documentation/netlink/specs/mptcp_pm.yaml | 5 +++--
include/uapi/linux/mptcp.h | 11 ++++++-----
include/uapi/linux/mptcp_pm.h | 4 ++--
net/mptcp/pm_netlink.c | 9 +++++++--
net/mptcp/protocol.c | 5 +----
tools/testing/selftests/net/mptcp/pm_nl_ctl.c | 9 ++++++++-
tools/testing/selftests/net/mptcp/userspace_pm.sh | 2 +-
7 files changed, 28 insertions(+), 17 deletions(-)
---
base-commit: 315f423be0d1ebe720d8fd4fa6bed68586b13d34
change-id: 20250916-net-next-mptcp-server-side-flag-0f002418946d
Best regards,
--
Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
This series backports 15 patches to update minmax.h in the 6.6.y branch,
aligning it with v6.17-rc7.
The ultimate goal is to synchronize all longterm branches so that they
include the full set of minmax.h changes.
The key motivation is to bring in commit d03eba99f5bf ("minmax: allow
min()/max()/clamp() if the arguments have the same signedness"), which
is missing in older kernels.
In mainline, this change enables min()/max()/clamp() to accept mixed
argument types, provided both have the same signedness. Without it,
backported patches that use these forms may trigger compiler warnings,
which escalate to build failures when -Werror is enabled.
David Laight (7):
minmax.h: add whitespace around operators and after commas
minmax.h: update some comments
minmax.h: reduce the #define expansion of min(), max() and clamp()
minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
minmax.h: move all the clamp() definitions after the min/max() ones
minmax.h: simplify the variants of clamp()
minmax.h: remove some #defines that are only expanded once
Linus Torvalds (8):
minmax: avoid overly complicated constant expressions in VM code
minmax: simplify and clarify min_t()/max_t() implementation
minmax: add a few more MIN_T/MAX_T users
minmax: make generic MIN() and MAX() macros available everywhere
minmax: simplify min()/max()/clamp() implementation
minmax: don't use max() in situations that want a C constant
expression
minmax: improve macro expansion and type checking
minmax: fix up min3() and max3() too
arch/um/drivers/mconsole_user.c | 2 +
arch/x86/mm/pgtable.c | 2 +-
drivers/edac/sb_edac.c | 4 +-
drivers/edac/skx_common.h | 1 -
.../drm/amd/display/modules/hdcp/hdcp_ddc.c | 2 +
.../drm/amd/pm/powerplay/hwmgr/ppevvmath.h | 14 +-
drivers/gpu/drm/amd/pm/swsmu/smu_cmn.c | 2 +-
drivers/gpu/drm/drm_color_mgmt.c | 2 +-
drivers/gpu/drm/radeon/evergreen_cs.c | 2 +
drivers/hwmon/adt7475.c | 24 +-
drivers/input/touchscreen/cyttsp4_core.c | 2 +-
drivers/irqchip/irq-sun6i-r.c | 2 +-
drivers/md/dm-integrity.c | 6 +-
drivers/media/dvb-frontends/stv0367_priv.h | 3 +
.../net/can/usb/etas_es58x/es58x_devlink.c | 2 +-
.../net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
drivers/net/fjes/fjes_main.c | 4 +-
drivers/nfc/pn544/i2c.c | 2 -
drivers/platform/x86/sony-laptop.c | 1 -
drivers/scsi/isci/init.c | 6 +-
.../pci/hive_isp_css_include/math_support.h | 5 -
fs/btrfs/tree-checker.c | 2 +-
include/linux/compiler.h | 9 +
include/linux/minmax.h | 228 +++++++++++-------
include/linux/pageblock-flags.h | 2 +-
kernel/trace/preemptirq_delay_test.c | 2 -
lib/btree.c | 1 -
lib/decompress_unlzma.c | 2 +
lib/vsprintf.c | 2 +-
mm/zsmalloc.c | 2 -
net/ipv4/proc.c | 2 +-
net/ipv6/proc.c | 2 +-
tools/testing/selftests/mm/mremap_test.c | 2 +
tools/testing/selftests/seccomp/seccomp_bpf.c | 2 +
34 files changed, 202 insertions(+), 146 deletions(-)
--
2.47.3