| Age | Commit message (Collapse) | Author |
|---|
|
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv fixes from Wei Liu:
- Fix an error handling issue in DRM driver (Christophe JAILLET)
- Fix some issues in framebuffer driver (Vitaly Kuznetsov)
- Two typo fixes (Jason Wang, Shaomin Deng)
- Drop unnecessary casting in kvp tool (Zhou Jie)
* tag 'hyperv-fixes-signed-20220912' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
Drivers: hv: Never allocate anything besides framebuffer from framebuffer memory region
Drivers: hv: Always reserve framebuffer region for Gen1 VMs
PCI: Move PCI_VENDOR_ID_MICROSOFT/PCI_DEVICE_ID_HYPERV_VIDEO definitions to pci_ids.h
tools: hv: kvp: remove unnecessary (void*) conversions
Drivers: hv: remove duplicate word in a comment
tools: hv: Remove an extraneous "the"
drm/hyperv: Fix an error handling path in hyperv_vmbus_probe()
|
|
We disable PTM during suspend because that allows some Root Ports to enter
lower-power PM states, which means we also need to disable PTM for all
downstream devices. Add pci_suspend_ptm() and pci_resume_ptm() for this
purpose.
pci_enable_ptm() and pci_disable_ptm() are for drivers to use to enable or
disable PTM. They use dev->ptm_enabled to keep track of whether PTM should
be enabled.
pci_suspend_ptm() and pci_resume_ptm() are PCI core-internal functions to
temporarily disable PTM during suspend and (depending on dev->ptm_enabled)
re-enable PTM during resume.
Enable/disable/suspend/resume all use internal __pci_enable_ptm() and
__pci_disable_ptm() functions that only update the PTM Control register.
Outline:
pci_enable_ptm(struct pci_dev *dev)
{
__pci_enable_ptm(dev);
dev->ptm_enabled = 1;
pci_ptm_info(dev);
}
pci_disable_ptm(struct pci_dev *dev)
{
if (dev->ptm_enabled) {
__pci_disable_ptm(dev);
dev->ptm_enabled = 0;
}
}
pci_suspend_ptm(struct pci_dev *dev)
{
if (dev->ptm_enabled)
__pci_disable_ptm(dev);
}
pci_resume_ptm(struct pci_dev *dev)
{
if (dev->ptm_enabled)
__pci_enable_ptm(dev);
}
Nothing currently calls pci_resume_ptm(); the suspend path saves the PTM
state before disabling PTM, so the PTM state restore in the resume path
implicitly re-enables it. A future change will use pci_resume_ptm() to fix
some problems with this approach.
Link: https://lore.kernel.org/r/20220909202505.314195-5-helgaas@kernel.org
Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
|
|
Cache the PTM Capability offset instead of searching for it every time we
enable/disable PTM or save/restore PTM state. No functional change
intended.
Link: https://lore.kernel.org/r/20220909202505.314195-2-helgaas@kernel.org
Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
|
|
https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux into arm/dt
Samsung DTS ARM64 changes for v6.0
1. Add binding headers for several Exynos850 and ExynosAutov9 clocks.
2. ExynosAutov9: Add FSYS clock controller nodes.
3. ExynosAutov9: Document serial compatible (used in DTS).
4. Exynos850: Add Audio, IS, MFC clock controllers. Add IOMMU nodes.
* tag 'samsung-dt64-6.1' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux:
dt-bindings: serial: samsung: add exynosautov9-uart compatible
arm64: dts: exynos: Add SysMMU nodes for Exynos850
arm64: dts: exynos: Add CMU_AUD, CMU_IS and CMU_MFCMSCL for Exynos850
arm64: dts: exynosautov9: add fsys0/1 clock DT nodes
dt-bindings: clock: exynos850: Add Exynos850 CMU_MFCMSCL
dt-bindings: clock: exynos850: Add Exynos850 CMU_IS
dt-bindings: clock: exynos850: Add Exynos850 CMU_AUD
dt-bindings: clock: exynosautov9: add schema for cmu_fsys0/1
dt-bindings: clock: exynosautov9: add fsys1 clock definitions
dt-bindings: clock: exynosautov9: add fys0 clock definitions
dt-bindings: clock: exynosautov9: correct clock numbering of peric0/c1
Link: https://lore.kernel.org/r/20220909150849.820523-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into arm/drivers
Powerdomain drivers for rv1126 and rk3588 socs, keep current state of
power-domains instead of always enabling when adding them, add rv1126
io domains and add binding for another "general register files" syscon.
* tag 'v6.1-rockchip-drivers1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip:
soc: rockchip: power-domain: add power domain support for rk3588
soc: rockchip: power-domain: do not enable domain when adding it
dt-bindings: power: rockchip: Add bindings for rk3588
dt-bindings: arm: rockchip: add rk5388 compatible string to pmu.yaml
dt-bindings: power: add power-domain header for rk3588
soc: rockchip: io-domain: Add RV1126 IO domains
dt-bindings: power: rockchip: Document RV1126 PMU IO domains
soc: rockchip: power-domain: Add RV1126 power domains
dt-bindings: power: rockchip: Document RV1126 power-controller
dt-bindings: power: Add power-domain header for RV1126
dt-bindings: soc: grf: add pcie30-{phy,pipe}-grf
Link: https://lore.kernel.org/r/2252399.ElGaqSPkdT@phil
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl into arm/drivers
Memory controller drivers for v6.1 - MediaTek
Add support for the mt8188 SMI memory controller.
* tag 'memory-controller-drv-mediatek-6.1' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl:
memory: mtk-smi: mt8188: Add SMI Support
memory: mtk-smi: Add enable IOMMU SMC command for MM master
memory: mtk-smi: Add return value for configure port function
dt-bindings: memory: mediatek: Add mt8188 smi binding
Link: https://lore.kernel.org/r/20220909153037.824092-4-krzysztof.kozlowski@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
We need the driver core and debugfs changes in this branch.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
1. Retrieve extended operational memory physical pointers from the
auxiliary device info.
2. Setup memory registers.
3. Notify firmware that the memory is ready by sending the memory
ready command.
4. Disable PXP device if GSC is not in PXP mode.
CC: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907215113.1596567-12-tomas.winkler@intel.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
|
|
Add slow_firmware flag to the mei auxiliary device info
to inform the mei driver about slow underlying firmware.
Such firmware will require to use larger operation timeouts.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907215113.1596567-4-tomas.winkler@intel.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
|
|
struct mei_aux_device is an interface structure
requires proper documenation.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907215113.1596567-3-tomas.winkler@intel.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
|
|
https://gitlab.freedesktop.org/agd5f/linux into drm-next
amd-drm-next-6.1-2022-09-08:
amdgpu:
- Mode2 reset for RDNA2
- Lots of new DC documentation
- Add documentation about different asic families
- DSC improvements
- Aldebaran fixes
- Misc spelling and grammar fixes
- GFXOFF stats support for vangogh
- DC frame size fixes
- NBIO 7.7 updates
- DCN 3.2 updates
- DCN 3.1.4 Updates
- SMU 13.x updates
- Misc bug fixes
- Rework DC register offset handling
- GC 11.x updates
- PSP 13.x updates
- SDMA 6.x updates
- GMC 11.x updates
- SR-IOV updates
- PSP fixes for TA unloading
- DSC passthrough support
- Misc code cleanups
amdkfd:
- ISA fixes for some GC 10.3 IPs
- Misc code cleanups
radeon:
- Delayed work flush fix
- Use time_after for some jiffies calculations
drm:
- DSC passthrough aux support
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908155202.57862-1-alexander.deucher@amd.com
|
|
Add drm_fb_build_fourcc_list() function that builds a list of supported
formats from native and emulated ones. Helpful for all drivers that do
format conversion as part of their plane updates. Update current caller.
v3:
* improve warnings on ignored formats (Sam)
v2:
* use u32 instead of uint32_t (Sam)
* print a warning if output array is too small (Sam)
* comment fixes (Sam)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-5-tzimmermann@suse.de
|
|
The macro DRM_MODE_INIT() initializes an instance of
struct drm_display_mode with typical parameters. Convert simpledrm
and also update the macro DRM_SIMPLE_MODE().
v3:
* fix DRM_MODE_INIT() docs (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-4-tzimmermann@suse.de
|
|
Add drm_crtc_helper_mode_valid_fixed(), which validates a given mode
against a display hardware's mode. Convert simpledrm and use it in a
few other drivers with static modes.
v4:
* remove empty line after opening brace
v2:
* rename 'static' and 'hw' to 'fixed' everywhere
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-3-tzimmermann@suse.de
|
|
Add drm_connector_helper_get_modes_fixed(), which duplicates a single
display mode for a connector. Convert drivers.
v2:
* rename 'static' and 'hw' to 'fixed' everywhere
* fix typo 'there' to 'their' (Sam)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-2-tzimmermann@suse.de
|
|
Test scripts:
cd /sys/fs/cgroup/blkio/
echo "8:0 1024" > blkio.throttle.write_bps_device
echo $$ > cgroup.procs
dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct &
dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct &
Test result:
10240 bytes (10 kB, 10 KiB) copied, 10.0134 s, 1.0 kB/s
10240 bytes (10 kB, 10 KiB) copied, 10.0135 s, 1.0 kB/s
The problem is that the second bio is finished after 10s instead of 20s.
Root cause:
1) second bio will be flagged:
__blk_throtl_bio
while (true) {
...
if (sq->nr_queued[rw]) -> some bio is throttled already
break
};
bio_set_flag(bio, BIO_THROTTLED); -> flag the bio
2) flagged bio will be dispatched without waiting:
throtl_dispatch_tg
tg_may_dispatch
tg_with_in_bps_limit
if (bps_limit == U64_MAX || bio_flagged(bio, BIO_THROTTLED))
*wait = 0; -> wait time is zero
return true;
commit 9f5ede3c01f9 ("block: throttle split bio in case of iops limit")
support to count split bios for iops limit, thus it adds flagged bio
checking in tg_with_in_bps_limit() so that split bios will only count
once for bps limit, however, it introduce a new problem that io throttle
won't work if multiple bios are throttled.
In order to fix the problem, handle iops/bps limit in different ways:
1) for iops limit, there is no flag to record if the bio is throttled,
and iops is always applied.
2) for bps limit, original bio will be flagged with BIO_BPS_THROTTLED,
and io throttle will ignore bio with the flag.
Noted this patch also remove the code to set flag in __bio_clone(), it's
introduced in commit 111be8839817 ("block-throttle: avoid double
charge"), and author thinks split bio can be resubmited and throttled
again, which is wrong because split bio will continue to dispatch from
caller.
Fixes: 9f5ede3c01f9 ("block: throttle split bio in case of iops limit")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220829022240.3348319-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
Batched completions can clear multiple bits, but we're only decrementing
the wait_cnt by one each time. This can cause waiters to never be woken,
stalling IO. Use the batched count instead.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215679
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220909184022.1709476-1-kbusch@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
There is a convention to use internal kernel types, so replace __u8 by u8.
Link: https://lkml.kernel.org/r/20220830172713.43686-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
set_mask_bits and bit_clear_unless. x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg (and
related move instruction in front of cmpxchg).
Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.
Link: https://lkml.kernel.org/r/20220822143851.3290-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Use atomic64_try_cmpxchg instead of
atomic64_cmpxchg (*ptr, old, new) == old in inode_set_max_iversion_raw,
inode_maybe_inc_version and inode_query_iversion. x86 CMPXCHG instruction
returns success in ZF flag, so this change saves a compare after cmpxchg
(and related move instruction in front of cmpxchg).
Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails, enabling further code simplifications.
The loop in inode_maybe_inc_iversion improves from:
5563: 48 89 ca mov %rcx,%rdx
5566: 48 89 c8 mov %rcx,%rax
5569: 48 83 e2 fe and $0xfffffffffffffffe,%rdx
556d: 48 83 c2 02 add $0x2,%rdx
5571: f0 48 0f b1 16 lock cmpxchg %rdx,(%rsi)
5576: 48 39 c1 cmp %rax,%rcx
5579: 0f 84 85 fc ff ff je 5204 <...>
557f: 48 89 c1 mov %rax,%rcx
5582: eb df jmp 5563 <...>
to:
5563: 48 89 c2 mov %rax,%rdx
5566: 48 83 e2 fe and $0xfffffffffffffffe,%rdx
556a: 48 83 c2 02 add $0x2,%rdx
556e: f0 48 0f b1 11 lock cmpxchg %rdx,(%rcx)
5573: 0f 84 8b fc ff ff je 5204 <...>
5579: eb e8 jmp 5563 <...>
Link: https://lkml.kernel.org/r/20220821193011.88208-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Only x86 has own release_thread(), introduce a new weak release_thread()
function to clean empty definitions in other ARCHs.
Link: https://lkml.kernel.org/r/20220819014406.32266-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Brian Cain <bcain@quicinc.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Acked-by: Stafford Horne <shorne@gmail.com> [openrisc]
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org> [LoongArch]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org> [csky]
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Xuerui Wang <kernel@xen0n.name>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "kexec, panic: Making crash_kexec() NMI safe", v4.
This patch (of 2):
Most acquistions of kexec_mutex are done via mutex_trylock() - those were
a direct "translation" from:
8c5a1cf0ad3a ("kexec: use a mutex for locking rather than xchg()")
there have however been two additions since then that use mutex_lock():
crash_get_memory_size() and crash_shrink_memory().
A later commit will replace said mutex with an atomic variable, and
locking operations will become atomic_cmpxchg(). Rather than having those
mutex_lock() become while (atomic_cmpxchg(&lock, 0, 1)), turn them into
trylocks that can return -EBUSY on acquisition failure.
This does halve the printable size of the crash kernel, but that's still
neighbouring 2G for 32bit kernels which should be ample enough.
Link: https://lkml.kernel.org/r/20220630223258.4144112-1-vschneid@redhat.com
Link: https://lkml.kernel.org/r/20220630223258.4144112-2-vschneid@redhat.com
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
commit 6c287605fd56 ("mm: remember exclusively mapped anonymous pages with
PG_anon_exclusive") made sure that when PageAnonExclusive() has to be
cleared during temporary unmapping of a page, that the PTE is
cleared/invalidated and that the TLB is flushed.
What we want to achieve in all cases is that we cannot end up with a pin on
an anonymous page that may be shared, because such pins would be
unreliable and could result in memory corruptions when the mapped page
and the pin go out of sync due to a write fault.
That TLB flush handling was inspired by an outdated comment in
mm/ksm.c:write_protect_page(), which similarly required the TLB flush in
the past to synchronize with GUP-fast. However, ever since general RCU GUP
fast was introduced in commit 2667f50e8b81 ("mm: introduce a general RCU
get_user_pages_fast()"), a TLB flush is no longer sufficient to handle
concurrent GUP-fast in all cases -- it only handles traditional IPI-based
GUP-fast correctly.
Peter Xu (thankfully) questioned whether that TLB flush is really
required. On architectures that send an IPI broadcast on TLB flush,
it works as expected. To synchronize with RCU GUP-fast properly, we're
conceptually fine, however, we have to enforce a certain memory order and
are missing memory barriers.
Let's document that, avoid the TLB flush where possible and use proper
explicit memory barriers where required. We shouldn't really care about the
additional memory barriers here, as we're not on extremely hot paths --
and we're getting rid of some TLB flushes.
We use a smp_mb() pair for handling concurrent pinning and a
smp_rmb()/smp_wmb() pair for handling the corner case of only temporary
PTE changes but permanent PageAnonExclusive changes.
One extreme example, whereby GUP-fast takes a R/O pin and KSM wants to
convert an exclusive anonymous page to a KSM page, and that page is already
mapped write-protected (-> no PTE change) would be:
Thread 0 (KSM) Thread 1 (GUP-fast)
(B1) Read the PTE
# (B2) skipped without FOLL_WRITE
(A1) Clear PTE
smp_mb()
(A2) Check pinned
(B3) Pin the mapped page
smp_mb()
(A3) Clear PageAnonExclusive
smp_wmb()
(A4) Restore PTE
(B4) Check if the PTE changed
smp_rmb()
(B5) Check PageAnonExclusive
Thread 1 will properly detect that PageAnonExclusive was cleared and
back off.
Note that we don't need a memory barrier between checking if the page is
pinned and clearing PageAnonExclusive, because stores are not
speculated.
The possible issues due to reordering are of theoretical nature so far
and attempts to reproduce the race failed.
Especially the "no PTE change" case isn't the common case, because we'd
need an exclusive anonymous page that's mapped R/O and the PTE is clean
in KSM code -- and using KSM with page pinning isn't extremely common.
Further, the clear+TLB flush we used for now implies a memory barrier.
So the problematic missing part should be the missing memory barrier
after pinning but before checking if the PTE changed.
Link: https://lkml.kernel.org/r/20220901083559.67446-1-david@redhat.com
Fixes: 6c287605fd56 ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Christoph von Recklinghausen <crecklin@redhat.com>
Cc: Don Dutile <ddutile@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "A few cleanup patches for hugetlb", v2.
This series contains a few cleanup patches to use helper functions to
simplify the codes, remove unneeded nid parameter and so on. More
details can be found in the respective changelogs.
This patch (of 10):
Make hugetlb_cma_check() static as it's only used inside mm/hugetlb.c.
Link: https://lkml.kernel.org/r/20220901120030.63318-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220901120030.63318-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
bh_submit_read() has no user anymore, just remove it.
Link: https://lkml.kernel.org/r/20220901133505.2510834-15-yi.zhang@huawei.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Now that all ll_rw_block() users has been replaced to new safe helpers,
we just remove it here.
Link: https://lkml.kernel.org/r/20220901133505.2510834-13-yi.zhang@huawei.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Current ll_rw_block() helper is fragile because it assumes that locked
buffer means it's under IO which is submitted by some other who holds
the lock, it skip buffer if it failed to get the lock, so it's only
safe on the readahead path. Unfortunately, now that most filesystems
still use this helper mistakenly on the sync metadata read path. There
is no guarantee that the one who holds the buffer lock always submit IO
(e.g. buffer_migrate_folio_norefs() after commit 88dbcbb3a484 ("blkdev:
avoid migration stalls for blkdev pages"), it could lead to false
positive -EIO when submitting reading IO.
This patch add some friendly buffer read helpers to prepare replacing
ll_rw_block() and similar calls. We can only call bh_readahead_[]
helpers for the readahead paths.
Link: https://lkml.kernel.org/r/20220901133505.2510834-3-yi.zhang@huawei.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "fs/buffer: remove ll_rw_block()", v2.
ll_rw_block() will skip locked buffer before submitting IO, it assumes
that locked buffer means it is under IO. This assumption is not always
true because we cannot guarantee every buffer lock path would submit IO.
After commit 88dbcbb3a484 ("blkdev: avoid migration stalls for blkdev
pages"), buffer_migrate_folio_norefs() becomes one exceptional case, and
there may be others. So ll_rw_block() is not safe on the sync read path,
we could get false positive EIO return value when filesystem reading
metadata. It seems that it could be only used on the readahead path.
Unfortunately, many filesystem misuse the ll_rw_block() on the sync read
path. This patch set just remove ll_rw_block() and add new friendly
helpers, which could prevent false positive EIO on the read metadata path.
Thanks for the suggestion from Jan, the original discussion is at [1].
patch 1: remove unused helpers in fs/buffer.c
patch 2: add new bh_read_[*] helpers
patch 3-11: remove all ll_rw_block() calls in filesystems
patch 12-14: do some leftover cleanups.
[1]. https://lore.kernel.org/linux-mm/20220825080146.2021641-1-chengzhihao1@huawei.com/
This patch (of 14):
No one use __breadahead_gfp() and sb_breadahead_unmovable() any more,
remove them.
Link: https://lkml.kernel.org/r/20220901133505.2510834-1-yi.zhang@huawei.com
Link: https://lkml.kernel.org/r/20220901133505.2510834-2-yi.zhang@huawei.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Heming Zhao <ocfs2-devel@oss.oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Simplify code by removing redundant CONFIG_TRANSPARENT_HUGEPAGE judgment.
No functional change.
Link: https://lkml.kernel.org/r/20220829095125.3284567-1-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Simplify code of has_transparent_hugepage define by using IS_BUILTIN.
No functional change.
Link: https://lkml.kernel.org/r/20220829095709.3287462-1-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
kswapd_run/stop() will set pgdat->kswapd to NULL, which could race with
kswapd_is_running() in kcompactd(),
kswapd_run/stop() kcompactd()
kswapd_is_running()
pgdat->kswapd // error or nomal ptr
verify pgdat->kswapd
// load non-NULL
pgdat->kswapd
pgdat->kswapd = NULL
task_is_running(pgdat->kswapd)
// Null pointer derefence
KASAN reports the null-ptr-deref shown below,
vmscan: Failed to start kswapd on node 0
...
BUG: KASAN: null-ptr-deref in kcompactd+0x440/0x504
Read of size 8 at addr 0000000000000024 by task kcompactd0/37
CPU: 0 PID: 37 Comm: kcompactd0 Kdump: loaded Tainted: G OE 5.10.60 #1
Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
Call trace:
dump_backtrace+0x0/0x394
show_stack+0x34/0x4c
dump_stack+0x158/0x1e4
__kasan_report+0x138/0x140
kasan_report+0x44/0xdc
__asan_load8+0x94/0xd0
kcompactd+0x440/0x504
kthread+0x1a4/0x1f0
ret_from_fork+0x10/0x18
At present kswapd/kcompactd_run() and kswapd/kcompactd_stop() are protected
by mem_hotplug_begin/done(), but without kcompactd(). There is no need to
involve memory hotplug lock in kcompactd(), so let's add a new mutex to
protect pgdat->kswapd accesses.
Also, because the kcompactd task will check the state of kswapd task, it's
better to call kcompactd_stop() before kswapd_stop() to reduce lock
conflicts.
[akpm@linux-foundation.org: add comments]
Link: https://lkml.kernel.org/r/20220827111959.186838-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Directly check state of struct memory_block, no need a single function.
Link: https://lkml.kernel.org/r/20220827112043.187028-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
All callers of find_get_pages_contig() have been removed, so it is no
longer needed.
Link: https://lkml.kernel.org/r/20220824004023.77310-8-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <clm@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: David Sterba <dsterb@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "Convert to filemap_get_folios_contig()", v3.
This patch series replaces find_get_pages_contig() with
filemap_get_folios_contig().
This patch (of 7):
This function is meant to replace find_get_pages_contig().
Unlike find_get_pages_contig(), filemap_get_folios_contig() no longer
takes in a target number of pages to find - It returns up to 15 contiguous
folios.
To be more consistent with filemap_get_folios(),
filemap_get_folios_contig() now also updates the start index passed in,
and takes an end index.
Link: https://lkml.kernel.org/r/20220824004023.77310-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20220824004023.77310-2-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Sterba <dsterb@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In commit 2f1ee0913ce5 ("Revert "mm: use early_pfn_to_nid in
page_ext_init""), we call page_ext_init() after page_alloc_init_late() to
avoid some panic problem. It seems that we cannot track early page
allocations in current kernel even if page structure has been initialized
early.
This patch introduces a new boot parameter 'early_page_ext' to resolve
this problem. If we pass it to the kernel, page_ext_init() will be moved
up and the feature 'deferred initialization of struct pages' will be
disabled to initialize the page allocator early and prevent the panic
problem above. It can help us to catch early page allocations. This is
useful especially when we find that the free memory value is not the same
right after different kernel booting.
[akpm@linux-foundation.org: fix section issue by removing __meminitdata]
Link: https://lkml.kernel.org/r/20220825102714.669-1-lizhe.67@bytedance.com
Signed-off-by: Li Zhe <lizhe.67@bytedance.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
For several years, MEMCG_CHARGE_BATCH was kept at 32 but with bigger
machines and the network intensive workloads requiring througput in Gbps,
32 is too small and makes the memcg charging path a bottleneck. For now,
increase it to 64 for easy acceptance to 6.0. We will need to revisit
this in future for ever increasing demand of higher performance.
Please note that the memcg charge path drain the per-cpu memcg charge
stock, so there should not be any oom behavior change. Though it does
have impact on rstat flushing and high limit reclaim backoff.
To evaluate the impact of this optimization, on a 72 CPUs machine, we
ran the following workload in a three level of cgroup hierarchy.
$ netserver -6
# 36 instances of netperf with following params
$ netperf -6 -H ::1 -l 60 -t TCP_SENDFILE -- -m 10K
Results (average throughput of netperf):
Without (6.0-rc1) 10482.7 Mbps
With patch 17064.7 Mbps (62.7% improvement)
With the patch, the throughput improved by 62.7%.
Link: https://lkml.kernel.org/r/20220825000506.239406-4-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Feng Tang <feng.tang@intel.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Michal Koutný" <mkoutny@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
With memcg v2 enabled, memcg->memory.usage is a very hot member for the
workloads doing memcg charging on multiple CPUs concurrently.
Particularly the network intensive workloads. In addition, there is a
false cache sharing between memory.usage and memory.high on the charge
path. This patch moves the usage into a separate cacheline and move all
the read most fields into separate cacheline.
To evaluate the impact of this optimization, on a 72 CPUs machine, we ran
the following workload in a three level of cgroup hierarchy.
$ netserver -6
# 36 instances of netperf with following params
$ netperf -6 -H ::1 -l 60 -t TCP_SENDFILE -- -m 10K
Results (average throughput of netperf):
Without (6.0-rc1) 10482.7 Mbps
With patch 12413.7 Mbps (18.4% improvement)
With the patch, the throughput improved by 18.4%.
One side-effect of this patch is the increase in the size of struct
mem_cgroup. For example with this patch on 64 bit build, the size of
struct mem_cgroup increased from 4032 bytes to 4416 bytes. However for
the performance improvement, this additional size is worth it. In
addition there are opportunities to reduce the size of struct mem_cgroup
like deprecation of kmem and tcpmem page counters and better packing.
Link: https://lkml.kernel.org/r/20220825000506.239406-3-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Feng Tang <feng.tang@intel.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Empty PTEs are passed to the pte_entry callback, not to pte_hole.
Link: https://lkml.kernel.org/r/3695521.kQq0lBPeGt@devpool047
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The below is one path where race between page_ext and offline of the
respective memory blocks will cause use-after-free on the access of
page_ext structure.
process1 process2
--------- ---------
a)doing /proc/page_owner doing memory offline
through offline_pages.
b) PageBuddy check is failed
thus proceed to get the
page_owner information
through page_ext access.
page_ext = lookup_page_ext(page);
migrate_pages();
.................
Since all pages are successfully
migrated as part of the offline
operation,send MEM_OFFLINE notification
where for page_ext it calls:
offline_page_ext()-->
__free_page_ext()-->
free_page_ext()-->
vfree(ms->page_ext)
mem_section->page_ext = NULL
c) Check for the PAGE_EXT
flags in the page_ext->flags
access results into the
use-after-free (leading to
the translation faults).
As mentioned above, there is really no synchronization between page_ext
access and its freeing in the memory_offline.
The memory offline steps(roughly) on a memory block is as below:
1) Isolate all the pages
2) while(1)
try free the pages to buddy.(->free_list[MIGRATE_ISOLATE])
3) delete the pages from this buddy list.
4) Then free page_ext.(Note: The struct page is still alive as it is
freed only during hot remove of the memory which frees the memmap,
which steps the user might not perform).
This design leads to the state where struct page is alive but the struct
page_ext is freed, where the later is ideally part of the former which
just representing the page_flags (check [3] for why this design is
chosen).
The abovementioned race is just one example __but the problem persists in
the other paths too involving page_ext->flags access(eg:
page_is_idle())__.
Fix all the paths where offline races with page_ext access by maintaining
synchronization with rcu lock and is achieved in 3 steps:
1) Invalidate all the page_ext's of the sections of a memory block by
storing a flag in the LSB of mem_section->page_ext.
2) Wait until all the existing readers to finish working with the
->page_ext's with synchronize_rcu(). Any parallel process that starts
after this call will not get page_ext, through lookup_page_ext(), for
the block parallel offline operation is being performed.
3) Now safely free all sections ->page_ext's of the block on which
offline operation is being performed.
Note: If synchronize_rcu() takes time then optimizations can be done in
this path through call_rcu()[2].
Thanks to David Hildenbrand for his views/suggestions on the initial
discussion[1] and Pavan kondeti for various inputs on this patch.
[1] https://lore.kernel.org/linux-mm/59edde13-4167-8550-86f0-11fc67882107@quicinc.com/
[2] https://lore.kernel.org/all/a26ce299-aed1-b8ad-711e-a49e82bdd180@quicinc.com/T/#u
[3] https://lore.kernel.org/all/6fa6b7aa-731e-891c-3efb-a03d6a700efa@redhat.com/
[quic_charante@quicinc.com: rename label `loop' to `ext_put_continue' per David]
Link: https://lkml.kernel.org/r/1661496993-11473-1-git-send-email-quic_charante@quicinc.com
Link: https://lkml.kernel.org/r/1660830600-9068-1-git-send-email-quic_charante@quicinc.com
Signed-off-by: Charan Teja Kalla <quic_charante@quicinc.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Fernand Sieber <sieberf@amazon.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pavan Kondeti <quic_pkondeti@quicinc.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
find_min_pfn_with_active_regions() is only called from free_area_init().
Open-code the PHYS_PFN(memblock_start_of_DRAM()) into free_area_init(),
and kill find_min_pfn_with_active_regions().
Link: https://lkml.kernel.org/r/20220815111017.39341-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
This Kconfig option is used by individual arch to set its desired
MAX_ORDER. Rename it to reflect its actual use.
Link: https://lkml.kernel.org/r/20220815143959.1511278-1-zi.yan@sent.com
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org> [LoongArch]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Qin Jian <qinjian@cqplus1.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The promotion hot threshold is workload and system configuration
dependent. So in this patch, a method to adjust the hot threshold
automatically is implemented. The basic idea is to control the number of
the candidate promotion pages to match the promotion rate limit. If the
hint page fault latency of a page is less than the hot threshold, we will
try to promote the page, and the page is called the candidate promotion
page.
If the number of the candidate promotion pages in the statistics interval
is much more than the promotion rate limit, the hot threshold will be
decreased to reduce the number of the candidate promotion pages.
Otherwise, the hot threshold will be increased to increase the number of
the candidate promotion pages.
To make the above method works, in each statistics interval, the total
number of the pages to check (on which the hint page faults occur) and the
hot/cold distribution need to be stable. Because the page tables are
scanned linearly in NUMA balancing, but the hot/cold distribution isn't
uniform along the address usually, the statistics interval should be
larger than the NUMA balancing scan period. So in the patch, the max scan
period is used as statistics interval and it works well in our tests.
Link: https://lkml.kernel.org/r/20220713083954.34196-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: osalvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zhong Jiang <zhongjiang-ali@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In NUMA balancing memory tiering mode, if there are hot pages in slow
memory node and cold pages in fast memory node, we need to promote/demote
hot/cold pages between the fast and cold memory nodes.
A choice is to promote/demote as fast as possible. But the CPU cycles and
memory bandwidth consumed by the high promoting/demoting throughput will
hurt the latency of some workload because of accessing inflating and slow
memory bandwidth contention.
A way to resolve this issue is to restrict the max promoting/demoting
throughput. It will take longer to finish the promoting/demoting. But
the workload latency will be better. This is implemented in this patch as
the page promotion rate limit mechanism.
The number of the candidate pages to be promoted to the fast memory node
via NUMA balancing is counted, if the count exceeds the limit specified by
the users, the NUMA balancing promotion will be stopped until the next
second.
A new sysctl knob kernel.numa_balancing_promote_rate_limit_MBps is added
for the users to specify the limit.
Link: https://lkml.kernel.org/r/20220713083954.34196-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: osalvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zhong Jiang <zhongjiang-ali@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "memory tiering: hot page selection", v4.
To optimize page placement in a memory tiering system with NUMA balancing,
the hot pages in the slow memory nodes need to be identified.
Essentially, the original NUMA balancing implementation selects the mostly
recently accessed (MRU) pages to promote. But this isn't a perfect
algorithm to identify the hot pages. Because the pages with quite low
access frequency may be accessed eventually given the NUMA balancing page
table scanning period could be quite long (e.g. 60 seconds). So in this
patchset, we implement a new hot page identification algorithm based on
the latency between NUMA balancing page table scanning and hint page
fault. Which is a kind of mostly frequently accessed (MFU) algorithm.
In NUMA balancing memory tiering mode, if there are hot pages in slow
memory node and cold pages in fast memory node, we need to promote/demote
hot/cold pages between the fast and cold memory nodes.
A choice is to promote/demote as fast as possible. But the CPU cycles and
memory bandwidth consumed by the high promoting/demoting throughput will
hurt the latency of some workload because of accessing inflating and slow
memory bandwidth contention.
A way to resolve this issue is to restrict the max promoting/demoting
throughput. It will take longer to finish the promoting/demoting. But
the workload latency will be better. This is implemented in this patchset
as the page promotion rate limit mechanism.
The promotion hot threshold is workload and system configuration
dependent. So in this patchset, a method to adjust the hot threshold
automatically is implemented. The basic idea is to control the number of
the candidate promotion pages to match the promotion rate limit.
We used the pmbench memory accessing benchmark tested the patchset on a
2-socket server system with DRAM and PMEM installed. The test results are
as follows,
pmbench score promote rate
(accesses/s) MB/s
------------- ------------
base 146887704.1 725.6
hot selection 165695601.2 544.0
rate limit 162814569.8 165.2
auto adjustment 170495294.0 136.9
From the results above,
With hot page selection patch [1/3], the pmbench score increases about
12.8%, and promote rate (overhead) decreases about 25.0%, compared with
base kernel.
With rate limit patch [2/3], pmbench score decreases about 1.7%, and
promote rate decreases about 69.6%, compared with hot page selection
patch.
With threshold auto adjustment patch [3/3], pmbench score increases about
4.7%, and promote rate decrease about 17.1%, compared with rate limit
patch.
Baolin helped to test the patchset with MySQL on a machine which contains
1 DRAM node (30G) and 1 PMEM node (126G).
sysbench /usr/share/sysbench/oltp_read_write.lua \
......
--tables=200 \
--table-size=1000000 \
--report-interval=10 \
--threads=16 \
--time=120
The tps can be improved about 5%.
This patch (of 3):
To optimize page placement in a memory tiering system with NUMA balancing,
the hot pages in the slow memory node need to be identified. Essentially,
the original NUMA balancing implementation selects the mostly recently
accessed (MRU) pages to promote. But this isn't a perfect algorithm to
identify the hot pages. Because the pages with quite low access frequency
may be accessed eventually given the NUMA balancing page table scanning
period could be quite long (e.g. 60 seconds). The most frequently
accessed (MFU) algorithm is better.
So, in this patch we implemented a better hot page selection algorithm.
Which is based on NUMA balancing page table scanning and hint page fault
as follows,
- When the page tables of the processes are scanned to change PTE/PMD
to be PROT_NONE, the current time is recorded in struct page as scan
time.
- When the page is accessed, hint page fault will occur. The scan
time is gotten from the struct page. And The hint page fault
latency is defined as
hint page fault time - scan time
The shorter the hint page fault latency of a page is, the higher the
probability of their access frequency to be higher. So the hint page
fault latency is a better estimation of the page hot/cold.
It's hard to find some extra space in struct page to hold the scan time.
Fortunately, we can reuse some bits used by the original NUMA balancing.
NUMA balancing uses some bits in struct page to store the page accessing
CPU and PID (referring to page_cpupid_xchg_last()). Which is used by the
multi-stage node selection algorithm to avoid to migrate pages shared
accessed by the NUMA nodes back and forth. But for pages in the slow
memory node, even if they are shared accessed by multiple NUMA nodes, as
long as the pages are hot, they need to be promoted to the fast memory
node. So the accessing CPU and PID information are unnecessary for the
slow memory pages. We can reuse these bits in struct page to record the
scan time. For the fast memory pages, these bits are used as before.
For the hot threshold, the default value is 1 second, which works well in
our performance test. All pages with hint page fault latency < hot
threshold will be considered hot.
It's hard for users to determine the hot threshold. So we don't provide a
kernel ABI to set it, just provide a debugfs interface for advanced users
to experiment. We will continue to work on a hot threshold automatic
adjustment mechanism.
The downside of the above method is that the response time to the workload
hot spot changing may be much longer. For example,
- A previous cold memory area becomes hot
- The hint page fault will be triggered. But the hint page fault
latency isn't shorter than the hot threshold. So the pages will
not be promoted.
- When the memory area is scanned again, maybe after a scan period,
the hint page fault latency measured will be shorter than the hot
threshold and the pages will be promoted.
To mitigate this, if there are enough free space in the fast memory node,
the hot threshold will not be used, all pages will be promoted upon the
hint page fault for fast response.
Thanks Zhong Jiang reported and tested the fix for a bug when disabling
memory tiering mode dynamically.
Link: https://lkml.kernel.org/r/20220713083954.34196-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20220713083954.34196-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Wei Xu <weixugc@google.com>
Cc: osalvador <osalvador@suse.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Zhong Jiang <zhongjiang-ali@linux.alibaba.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
gfp_migratetype() also expects GFP_RECLAIMABLE and
GFP_MOVABLE|GFP_RECLAIMABLE to be shiftable into MIGRATE_* enum values, so
add some more BUILD_BUG_ONs to reflect this assumption.
Link: https://linux-review.googlesource.com/id/Iae64e2182f75c3aca776a486b71a72571d66d83e
Link: https://lkml.kernel.org/r/20220726230241.3770532-1-pcc@google.com
Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The return value of set_hugetlb_cgroup and set_hugetlb_cgroup_rsvd are
always ignored. Remove them to clean up the code.
Link: https://lkml.kernel.org/r/20220729080106.12752-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
By default kfence allocation can happen for any slab object, whose size is
up to PAGE_SIZE, as long as that allocation is the first allocation after
expiration of kfence sample interval. But in certain debugging scenarios
we may be interested in debugging corruptions involving some specific slub
objects like dentry or ext4_* etc. In such cases limiting kfence for
allocations involving only specific slub objects will increase the
probablity of catching the issue since kfence pool will not be consumed by
other slab objects.
This patch introduces a sysfs interface
'/sys/kernel/slab/<name>/skip_kfence' to disable kfence for specific
slabs. Having the interface work in this way does not impact
current/default behavior of kfence and allows us to use kfence for
specific slabs (when needed) as well. The decision to skip/use kfence is
taken depending on whether kmem_cache.flags has (newly introduced)
SLAB_SKIP_KFENCE flag set or not.
Link: https://lkml.kernel.org/r/20220814195353.2540848-1-imran.f.khan@oracle.com
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Muchun Song found that after MPOL_PREFERRED_MANY policy was introduced in
commit b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple
preferred nodes"), the policy_nodemask_current()'s semantics for this new
policy has been changed, which returns 'preferred' nodes instead of
'allowed' nodes.
With the changed semantic of policy_nodemask_current, a task with
MPOL_PREFERRED_MANY policy could fail to get its reservation even though
it can fall back to other nodes (either defined by cpusets or all online
nodes) for that reservation failing mmap calles unnecessarily early.
The fix is to not consider MPOL_PREFERRED_MANY for reservations at all
because they, unlike MPOL_MBIND, do not pose any actual hard constrain.
Michal suggested the policy_nodemask_current() is only used by hugetlb,
and could be moved to hugetlb code with more explicit name to enforce the
'allowed' semantics for which only MPOL_BIND policy matters.
apply_policy_zone() is made extern to be called in hugetlb code and its
return value is changed to bool.
[1]. https://lore.kernel.org/lkml/20220801084207.39086-1-songmuchun@bytedance.com/t/
Link: https://lkml.kernel.org/r/20220805005903.95563-1-feng.tang@intel.com
Fixes: b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple preferred nodes")
Signed-off-by: Feng Tang <feng.tang@intel.com>
Reported-by: Muchun Song <songmuchun@bytedance.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The magic number 0 and 1 are used in several places in vmscan.c.
Define macros for them to improve code readability.
Link: https://lkml.kernel.org/r/20220808005644.1721066-1-yang.yang29@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Historically, it has been shown that intercepting kernel faults with
userfaultfd (thereby forcing the kernel to wait for an arbitrary amount of
time) can be exploited, or at least can make some kinds of exploits
easier. So, in 37cd0575b8 "userfaultfd: add UFFD_USER_MODE_ONLY" we
changed things so, in order for kernel faults to be handled by
userfaultfd, either the process needs CAP_SYS_PTRACE, or this sysctl must
be configured so that any unprivileged user can do it.
In a typical implementation of a hypervisor with live migration (take
QEMU/KVM as one such example), we do indeed need to be able to handle
kernel faults. But, both options above are less than ideal:
- Toggling the sysctl increases attack surface by allowing any
unprivileged user to do it.
- Granting the live migration process CAP_SYS_PTRACE gives it this
ability, but *also* the ability to "observe and control the
execution of another process [...], and examine and change [its]
memory and registers" (from ptrace(2)). This isn't something we need
or want to be able to do, so granting this permission violates the
"principle of least privilege".
This is all a long winded way to say: we want a more fine-grained way to
grant access to userfaultfd, without granting other additional permissions
at the same time.
To achieve this, add a /dev/userfaultfd misc device. This device provides
an alternative to the userfaultfd(2) syscall for the creation of new
userfaultfds. The idea is, any userfaultfds created this way will be able
to handle kernel faults, without the caller having any special
capabilities. Access to this mechanism is instead restricted using e.g.
standard filesystem permissions.
[axelrasmussen@google.com: Handle misc_register() failure properly]
Link: https://lkml.kernel.org/r/20220819205201.658693-3-axelrasmussen@google.com
Link: https://lkml.kernel.org/r/20220808175614.3885028-3-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Nadav Amit <namit@vmware.com>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
