During the static checks nr_states has been mentioned by the kernel test
robot. Fix the warning in those 2 places.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
NVIDIA's upcoming Grace Hopper Superchip provides a PCI-like device
for the on-chip GPU that is the logical OS representation of the
internal proprietary chip-to-chip cache coherent interconnect.
The device is peculiar compared to a real PCI device in that whilst
there is a real 64b PCI BAR1 (comprising region 2 & region 3) on the
device, it is not used to access device memory once the faster
chip-to-chip interconnect is initialized (occurs at the time of host
system boot). The device memory is accessed instead using the chip-to-chip
interconnect that is exposed as a contiguous physically addressable
region on the host. This device memory aperture can be obtained from host
ACPI table using device_property_read_u64(), according to the FW
specification. Since the device memory is cache coherent with the CPU,
it can be mmap into the user VMA with a cacheable mapping using
remap_pfn_range() and used like a regular RAM. The device memory
is not added to the host kernel, but mapped directly as this reduces
memory wastage due to struct pages.
There is also a requirement of a minimum reserved 1G uncached region
(termed as resmem) to support the Multi-Instance GPU (MIG) feature [1].
This is to work around a HW defect. Based on [2], the requisite properties
(uncached, unaligned access) can be achieved through a VM mapping (S1)
of NORMAL_NC and host (S2) mapping with MemAttr[2:0]=0b101. To provide
a different non-cached property to the reserved 1G region, it needs to
be carved out from the device memory and mapped as a separate region
in Qemu VMA with pgprot_writecombine(). pgprot_writecombine() sets the
Qemu VMA page properties (pgprot) as NORMAL_NC.
Provide a VFIO PCI variant driver that adapts the unique device memory
representation into a more standard PCI representation facing userspace.
The variant driver exposes these two regions - the non-cached reserved
(resmem) and the cached rest of the device memory (termed as usemem) as
separate VFIO 64b BAR regions. This is divergent from the baremetal
approach, where the device memory is exposed as a device memory region.
The decision for a different approach was taken in view of the fact that
it would necessiate additional code in Qemu to discover and insert those
regions in the VM IPA, along with the additional VM ACPI DSDT changes to
communicate the device memory region IPA to the VM workloads. Moreover,
this behavior would have to be added to a variety of emulators (beyond
top of tree Qemu) out there desiring grace hopper support.
Since the device implements 64-bit BAR0, the VFIO PCI variant driver
maps the uncached carved out region to the next available PCI BAR (i.e.
comprising of region 2 and 3). The cached device memory aperture is
assigned BAR region 4 and 5. Qemu will then naturally generate a PCI
device in the VM with the uncached aperture reported as BAR2 region,
the cacheable as BAR4. The variant driver provides emulation for these
fake BARs' PCI config space offset registers.
The hardware ensures that the system does not crash when the memory
is accessed with the memory enable turned off. It synthesis ~0 reads
and dropped writes on such access. So there is no need to support the
disablement/enablement of BAR through PCI_COMMAND config space register.
The memory layout on the host looks like the following:
devmem (memlength)
|--------------------------------------------------|
|-------------cached------------------------|--NC--|
| |
usemem.memphys resmem.memphys
PCI BARs need to be aligned to the power-of-2, but the actual memory on the
device may not. A read or write access to the physical address from the
last device PFN up to the next power-of-2 aligned physical address
results in reading ~0 and dropped writes. Note that the GPU device
driver [6] is capable of knowing the exact device memory size through
separate means. The device memory size is primarily kept in the system
ACPI tables for use by the VFIO PCI variant module.
Note that the usemem memory is added by the VM Nvidia device driver [5]
to the VM kernel as memblocks. Hence make the usable memory size memblock
(MEMBLK_SIZE) aligned. This is a hardwired ABI value between the GPU FW and
VFIO driver. The VM device driver make use of the same value for its
calculation to determine USEMEM size.
Currently there is no provision in KVM for a S2 mapping with
MemAttr[2:0]=0b101, but there is an ongoing effort to provide the same [3].
As previously mentioned, resmem is mapped pgprot_writecombine(), that
sets the Qemu VMA page properties (pgprot) as NORMAL_NC. Using the
proposed changes in [3] and [4], KVM marks the region with
MemAttr[2:0]=0b101 in S2.
If the device memory properties are not present, the driver registers the
vfio-pci-core function pointers. Since there are no ACPI memory properties
generated for the VM, the variant driver inside the VM will only use
the vfio-pci-core ops and hence try to map the BARs as non cached. This
is not a problem as the CPUs have FWB enabled which blocks the VM
mapping's ability to override the cacheability set by the host mapping.
This goes along with a qemu series [6] to provides the necessary
implementation of the Grace Hopper Superchip firmware specification so
that the guest operating system can see the correct ACPI modeling for
the coherent GPU device. Verified with the CUDA workload in the VM.
[1] https://www.nvidia.com/en-in/technologies/multi-instance-gpu/
[2] section D8.5.5 of https://developer.arm.com/documentation/ddi0487/latest/
[3] https://lore.kernel.org/all/20240211174705.31992-1-ankita@nvidia.com/
[4] https://lore.kernel.org/all/20230907181459.18145-2-ankita@nvidia.com/
[5] https://github.com/NVIDIA/open-gpu-kernel-modules
[6] https://lore.kernel.org/all/20231203060245.31593-1-ankita@nvidia.com/
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Zhi Wang <zhi.wang.linux@gmail.com>
Signed-off-by: Aniket Agashe <aniketa@nvidia.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20240220115055.23546-4-ankita@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
range_intersect_range determines an overlap between two ranges. If an
overlap, the helper function returns the overlapping offset and size.
The VFIO PCI variant driver emulates the PCI config space BAR offset
registers. These offset may be accessed for read/write with a variety
of lengths including sub-word sizes from sub-word offsets. The driver
makes use of this helper function to read/write the targeted part of
the emulated register.
Make this a vfio_pci_core function, rename and export as GPL. Also
update references in virtio driver.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20240220115055.23546-3-ankita@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
do_io_rw() is used to read/write to the device MMIO. The grace hopper
VFIO PCI variant driver require this functionality to read/write to
its memory.
Rename this as vfio_pci_core functions and export as GPL.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20240220115055.23546-2-ankita@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that the driver core can properly handle constant struct bus_type,
move the mdev_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Link: https://lore.kernel.org/r/20240208-bus_cleanup-vfio-v1-1-ed5da3019949@marliere.net
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Let firmware knows upon leaving PRE_COPY back to RUNNING as of some
error in the target/migration cancellation.
This will let firmware cleaning its internal resources that were turned
on upon PRE_COPY.
The flow is based on the device specification in this area.
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20240205124828.232701-6-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Block incremental query which is state-dependent once the migration file
was previously marked with state error.
This may prevent redundant calls to firmware upon PRE_COPY which will
end-up with a failure and a syndrome printed in dmesg.
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20240205124828.232701-5-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The SAVE command uses the async command interface over the PF.
Upon a failure in the firmware -EREMOTEIO is returned.
In that case call mlx5_cmd_out_err() to let it print the command failure
details including the firmware syndrome.
Note:
The other commands in the driver use the sync command interface in a way
that a firmware syndrome is printed upon an error inside mlx5_core.
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20240205124828.232701-4-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add support for tracker object change event by referring to its
MLX5_EVENT_TYPE_OBJECT_CHANGE event when occurs.
This lets the driver recognize whether the firmware moved the tracker
object to an error state.
In that case, the driver will skip/block any usage of that object
including an early exit in case the object was previously marked with an
error.
This functionality also covers the case when no CQE is delivered as of
the error state.
The driver was adapted to the device specification to handle the above.
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20240205124828.232701-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add the IFC related bits for query tracker.
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Leon Romanovsky <leon@kernel.org>
Link: https://lore.kernel.org/r/20240205124828.232701-2-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
This is a blocking notifier callback, so errno isn't a proper return
value. Use WARN_ON to small allocation failures.
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Link: https://lore.kernel.org/r/20240115063434.20278-1-chentao@kylinos.cn
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
set_memory_ro() and set_memory_rw() can fail, leaving memory
unprotected.
Take the returned value into account and abort in case of
failure.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In struct pt_regs, member pstate is after member pc. Move offset macro
of pstate after offset macro of pc to improve readability a little.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20240130175504.106364-1-shikemeng@huaweicloud.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In function get_pkg_num() if fopen_or_die() succeeds it returns a file
pointer to be used. But fclose() is never called before returning from
the function.
Signed-off-by: Samasth Norway Ananda <samasth.norway.ananda@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently the default compression algorithm is selected based on
compile time options. Introduce a module parameter "hibernate.compressor"
to override this behaviour.
Different compression algorithms have different characteristics and
hibernation may benefit when it uses any of these algorithms, especially
when a secondary algorithm(LZ4) offers better decompression speeds over
a default algorithm(LZO), which in turn reduces hibernation image
restore time.
Users can override the default algorithm in two ways:
1) Passing "hibernate.compressor" as kernel command line parameter.
Usage:
LZO: hibernate.compressor=lzo
LZ4: hibernate.compressor=lz4
2) Specifying the algorithm at runtime.
Usage:
LZO: echo lzo > /sys/module/hibernate/parameters/compressor
LZ4: echo lz4 > /sys/module/hibernate/parameters/compressor
Currently LZO and LZ4 are the supported algorithms. LZO is the default
compression algorithm used with hibernation.
Signed-off-by: Nikhil V <quic_nprakash@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure. Ensure the allocation was successful
by checking the pointer validity.
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Link: https://lore.kernel.org/r/20240118100206.213928-1-chentao@kylinos.cn
Signed-off-by: Kees Cook <keescook@chromium.org>
The efi-pstore module parameter "pstore_disable" warrants that users
are able to deactivate such backend. There is also a Kconfig option
for the default value of this parameter. It was originally added due
to some bad UEFI FW implementations that could break with many variables
written.
Some distros (such as Arch Linux) set this in their config file still
nowadays. And once it is set, even being a writable module parameter,
there is effectively no way to make use of efi-pstore anymore.
If "pstore_disable" is set to true, the init function of the module exits
early and is never called again after the initcall processing.
Let's switch this module parameter to have a callback and perform the
pstore backend registration again each time it's set from Y->N (and
vice-versa). With this, the writable nature of the parameter starts to
make sense, given that users now can switch back to using efi-pstore
or not during runtime by writing into it.
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Link: https://lore.kernel.org/r/20240103184053.226203-1-gpiccoli@igalia.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Enable PSTORE_RAM, that is the ramoops driver, in the defconfig, to
allow logging and retrieving panics and oopses to/from RAM automatically
for platforms that have a ramoops reserved memory node in DT.
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: David Heidelberg <david@ixit.cz>
Link: https://lore.kernel.org/r/20240110210600.787703-3-nfraprado@collabora.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Register the compatible for this module on the module device table so
it can be automatically loaded when a matching DT node is present,
allowing logging of panics and oopses without any intervention.
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240110210600.787703-2-nfraprado@collabora.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Unloading a modular pstore backend with records in pstorefs would
trigger the dput() double-drop warning:
WARNING: CPU: 0 PID: 2569 at fs/dcache.c:762 dput.part.0+0x3f3/0x410
Using the combo of d_drop()/dput() (as mentioned in
Documentation/filesystems/vfs.rst) isn't the right approach here, and
leads to the reference counting problem seen above. Use d_invalidate()
and update the code to not bother checking for error codes that can
never happen.
Suggested-by: Alexander Viro <viro@zeniv.linux.org.uk>
Fixes: 609e28bb13 ("pstore: Remove filesystem records when backend is unregistered")
Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-hardening@vger.kernel.org
Currently zram allocates 2 physically contiguous pages per-CPU's
compression stream (we may have up to 4 streams per-CPU). Since those
buffers are per-CPU we allocate them from CPU hotplug path, which may have
higher risks of failed allocations on devices with fragmented memory.
Switch to virtually contiguous allocations - crypto comp does not seem
impose requirements on compression working buffers to be physically
contiguous.
Link: https://lkml.kernel.org/r/20240213065400.6561-1-21cnbao@gmail.com
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All platforms could benefit from page order check against MAX_PAGE_ORDER
before allocating a CMA area for gigantic hugetlb pages. Let's move this
check from individual platforms to generic hugetlb.
Link: https://lkml.kernel.org/r/20240209054221.1403364-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The reclaimable number of anon pages used to set initial reclaim priority
is only based on get_swappiness(). Use can_reclaim_anon_pages() to
include NUMA node demotion.
Also move the swappiness handling of when !__GFP_IO in
try_to_shrink_lruvec() into isolate_folios().
Link: https://lkml.kernel.org/r/20240214060538.3524462-6-kinseyho@google.com
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename max_seq to seq in struct lru_gen_mm_walk to keep consistent with
struct lru_gen_mm_state. Note that seq is not always up to date with
max_seq from lru_gen_folio.
No functional changes.
Link: https://lkml.kernel.org/r/20240214060538.3524462-5-kinseyho@google.com
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
struct lruvec* is already a field of struct lru_gen_mm_walk. Remove the
parameter struct lruvec* into functions that already have access to struct
lru_gen_mm_walk*.
Also, we do not need to handle reset histogram stats when
!should_walk_mmu(). Remove the call to reset_mm_stats() in
iterate_mm_list_nowalk().
Link: https://lkml.kernel.org/r/20240214060538.3524462-4-kinseyho@google.com
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
scan_control *sc does not need to be passed into should_run_aging(), as it
provides only the reclaim priority. This can be moved to
get_nr_to_scan().
Refactor should_run_aging() and get_nr_to_scan() to improve code
readability. No functional changes.
Link: https://lkml.kernel.org/r/20240214060538.3524462-3-kinseyho@google.com
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/mglru: code cleanup and refactoring"
This provides MGLRU code cleanup and refactoring for better readability.
This patch (of 5):
struct scan_control *sc is currently passed into try_to_inc_max_seq() and
run_aging(). This parameter is not used.
Drop the unused parameter struct scan_control *sc. No functional change.
Link: https://lkml.kernel.org/r/20240214060538.3524462-1-kinseyho@google.com
Link: https://lkml.kernel.org/r/20240214060538.3524462-2-kinseyho@google.com
Signed-off-by: Kinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The out-of-bounds test allocates an object that is three bytes too short
in order to validate the bounds checking. Starting with gcc-14, this
causes a compile-time warning as gcc has grown smart enough to understand
the sizeof() logic:
mm/kasan/kasan_test.c: In function 'kmalloc_oob_16':
mm/kasan/kasan_test.c:443:14: error: allocation of insufficient size '13' for type 'struct <anonymous>' with size '16' [-Werror=alloc-size]
443 | ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
| ^
Hide the actual computation behind a RELOC_HIDE() that ensures
the compiler misses the intentional bug.
Link: https://lkml.kernel.org/r/20240212111609.869266-1-arnd@kernel.org
Fixes: 3f15801cdc ("lib: add kasan test module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The memalloc_noreclaim_save() function currently has no documentation
comment, so the implications of its usage are not obvious. Namely that it
not only prevents entering reclaim (as the name suggests), but also allows
using all memory reserves and thus should be only used in contexts that
are allocating memory to free memory. This may lead to new improper
usages being added.
Thus add a documenting comment, based on the description of
__GFP_MEMALLOC. While at it, also document memalloc_pin_save() so that
all the memalloc_ scopes are documented. For those already documented,
add missing Return: descriptions, and mark Context: description per
kernel-docs style guide.
In the comments describing the relevant PF_MEMALLOC flags, refer to their
scope setting functions.
[vbabka@suse.cz: fix issues that Mike pointed out]
Link: https://lkml.kernel.org/r/20240215095827.13756-2-vbabka@suse.cz
Link: https://lkml.kernel.org/r/20240212182950.32730-2-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We may encounter duplicate entry in the zswap_store():
1. swap slot that freed to per-cpu swap cache, doesn't invalidate
the zswap entry, then got reused. This has been fixed.
2. !exclusive load mode, swapin folio will leave its zswap entry
on the tree, then swapout again. This has been removed.
3. one folio can be dirtied again after zswap_store(), so need to
zswap_store() again. This should be handled correctly.
So we must invalidate the old duplicate entry before inserting the
new one, which actually doesn't have to be done at the beginning
of zswap_store().
The good point is that we don't need to lock the tree twice in the normal
store success path. And cleanup the loop as we are here.
Note we still need to invalidate the old duplicate entry when store failed
or zswap is disabled , otherwise the new data in swapfile could be
overwrite by the old data in zswap pool when lru writeback.
Link: https://lkml.kernel.org/r/20240209044112.3883835-1-chengming.zhou@linux.dev
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Every test result report in the compaction test prints a distinct log
messae, and some of the reports print a name that varies at runtime. This
causes problems for automation since a lot of automation software uses the
printed string as the name of the test, if the name varies from run to run
and from pass to fail then the automation software can't identify that a
test changed result or that the same tests are being run.
Refactor the logging to use a consistent name when printing the result of
the test, printing the existing messages as diagnostic information instead
so they are still available for people trying to interpret the results.
Link: https://lkml.kernel.org/r/20240209-kselftest-mm-cleanup-v1-2-a3c0386496b5@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "selftests/mm: Output cleanups for the compaction test".
A couple of small updates for the check_compaction selftest which make
it play more nicely with test automation systems.
This patch (of 2):
When the compaction test is run it checks to make sure that prerequistives
the test requires are available and skips the tests if not. When this
happens we log the test as a pass rather than a skip, log as a skip so
that the distinction is clear and automation can see unexpected skips.
Link: https://lkml.kernel.org/r/20240209-kselftest-mm-cleanup-v1-0-a3c0386496b5@kernel.org
Link: https://lkml.kernel.org/r/20240209-kselftest-mm-cleanup-v1-1-a3c0386496b5@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Refactor compact_node() to handle both proactive and synchronous compact
memory, which cleanups code a bit.
Link: https://lkml.kernel.org/r/20240208013607.1731817-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This adds the following new sysfs file tracking the number of successfully
released pages from a given CMA heap area. This file will be available
via CONFIG_CMA_SYSFS and help in determining active CMA pages available on
the CMA heap area. This adds a new 'nr_pages_released' (CONFIG_CMA_SYSFS)
into 'struct cma' which gets updated during cma_release().
/sys/kernel/mm/cma/<cma-heap-area>/release_pages_success
After this change, an user will be able to find active CMA pages available
in a given CMA heap area via the following method.
Active pages = alloc_pages_success - release_pages_success
That's valuable information for both software designers, and system admins
as it allows them to tune the number of CMA pages available in the system.
This increases user visibility for allocated CMA area and its
utilization.
Link: https://lkml.kernel.org/r/20240206045731.472759-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON debugfs selftests dependency checker assumes debugfs would be
mounted at /sys/kernel/debug. That would be ok for many cases, but some
systems might mounted the file system on some different places. Parse the
real mount point using /proc/mounts file.
Link: https://lkml.kernel.org/r/20240207203134.69976-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Commit ebb3f994dd ("mm/damon/dbgfs: fix 'struct pid' leaks in
'dbgfs_target_ids_write()'") fixes a pid leak bug in DAMON debugfs
interface, namely dbgfs_target_ids_write() function. Add a selftest for
the issue to prevent the problem from mistakenly recurring.
Link: https://lkml.kernel.org/r/20240207203134.69976-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
commit 3479641796 ("mm/damon/dbgfs: protect targets destructions with
kdamond_lock") fixed a race of DAMON debugfs interface. Specifically, the
race was happening between target_ids_read() and dbgfs_before_terminate().
Add a test for the issue to prevent the problem from accidentally
recurring.
Link: https://lkml.kernel.org/r/20240207203134.69976-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a selftest for DAMOS apply intervals. It runs two schemes having
different apply interval agains an artificial memory access workload, and
check if the scheme with smaller apply interval was applied more
frequently.
Link: https://lkml.kernel.org/r/20240207203134.69976-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a selftest for verifying the DAMOS quota feature. The test is very
similar to sysfs_update_schemes_tried_regions_wss_estimation.py. It
starts an artificial workload of 20 MiB working set, run DAMON to find the
working set size, but with 1 MiB/100 ms size quota. Then, it collect the
DAMON-found working set size every 100 ms and check if the quota was
always applied as expected. For the confirmation, the tests shows the
stat-applied region size and the qt_exceeds stat.
Link: https://lkml.kernel.org/r/20240207203134.69976-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Update the test-purpose DAMON sysfs control Python module to support DAMOS
apply interval.
Link: https://lkml.kernel.org/r/20240207203134.69976-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Update the test-purpose DAMON sysfs control Python module to support DAMOS
stats.
Link: https://lkml.kernel.org/r/20240207203134.69976-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "selftests/damon: add more tests for core functionalities and
corner cases".
Continue DAMON selftests' test coverage improvement works with a trivial
improvement of the test code itself. The sequence of the patches in
patchset is as follows.
The first five patches add two DAMON core functionalities tests. Those
begins with three patches (patches 1-3) that update the test-purpose DAMON
sysfs interface wrapper to support DAMOS quota, stats, and apply interval
features, respectively. The fourth patch implements and adds a selftest
for DAMOS quota feature, using the DAMON sysfs interface wrapper's newly
added support of the quota and the stats feature. The fifth patch further
implements and adds a selftest for DAMOS apply interval using the DAMON
sysfs interface wrapper's newly added support of the apply interval and
the stats feature.
Two patches (patches 6 and 7) for implementing and adding two corner cases
handling selftests follow. Those try to avoid two previously fixed bugs
from recurring.
Finally, a patch for making DAMON debugfs selftests dependency checker to
use /proc/mounts instead of the hard-coded mount point assumption follows.
This patch (of 8):
Update the test-purpose DAMON sysfs control Python module to support DAMOS
quota.
Link: https://lkml.kernel.org/r/20240207203134.69976-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20240207203134.69976-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Some architectures, such as arm, have implemented optimized copy_page for
full page copying.
Replace the full page memcpy with copy_page to take advantage of the
optimization.
Link: https://lkml.kernel.org/r/20231007070554.8657-1-mark-pk.tsai@mediatek.com
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: YJ Chiang <yj.chiang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently, when a demotion occurs, it will prioritize selecting a node
from the preferred targets as the destination node for the demotion. If
the preferred node does not meet the requirements, it will try from all
the lower memory tier nodes until it finds a suitable demotion destination
node or ultimately fails.
However, the demotion target information isn't exposed to the users,
especially the preferred target information, which relies on more factors.
This makes it hard for users to understand the exact demotion behavior.
Rather than having a new sysfs interface to expose this information,
printing directly to kernel messages, just like the current page
allocation fallback order does.
A dmesg example with this patch is as follows:
[ 0.704860] Demotion targets for Node 0: null
[ 0.705456] Demotion targets for Node 1: null
// node 2 is onlined
[ 32.259775] Demotion targets for Node 0: perferred: 2, fallback: 2
[ 32.261290] Demotion targets for Node 1: perferred: 2, fallback: 2
[ 32.262726] Demotion targets for Node 2: null
// node 3 is onlined
[ 42.448809] Demotion targets for Node 0: perferred: 2, fallback: 2-3
[ 42.450704] Demotion targets for Node 1: perferred: 2, fallback: 2-3
[ 42.452556] Demotion targets for Node 2: perferred: 3, fallback: 3
[ 42.454136] Demotion targets for Node 3: null
// node 4 is onlined
[ 52.676833] Demotion targets for Node 0: perferred: 2, fallback: 2-4
[ 52.678735] Demotion targets for Node 1: perferred: 2, fallback: 2-4
[ 52.680493] Demotion targets for Node 2: perferred: 4, fallback: 3-4
[ 52.682154] Demotion targets for Node 3: null
[ 52.683405] Demotion targets for Node 4: null
// node 5 is onlined
[ 62.931902] Demotion targets for Node 0: perferred: 2, fallback: 2-5
[ 62.938266] Demotion targets for Node 1: perferred: 5, fallback: 2-5
[ 62.943515] Demotion targets for Node 2: perferred: 4, fallback: 3-4
[ 62.947471] Demotion targets for Node 3: null
[ 62.949908] Demotion targets for Node 4: null
[ 62.952137] Demotion targets for Node 5: perferred: 3, fallback: 3-4
Regarding this requirement, we have previously discussed [1]. The initial
proposal involved introducing a new sysfs interface. However, due to
concerns about potential changes and compatibility issues with the
interface in the future, a consensus was not reached with the community.
Therefore, this time, we are directly printing out the information.
[1] https://lore.kernel.org/all/d1d5add8-8f4a-4578-8bf0-2cbe79b09989@fujitsu.com/
Link: https://lkml.kernel.org/r/20240206020151.605516-1-lizhijian@fujitsu.com
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON sysfs interface need to access kdamond-touching data for some of
kdamond user commands. It uses ->after_aggregation() kdamond callback to
safely access the data in the case. It had to use the aggregation
interval callback because that was the only callback that users can access
complete monitoring results.
Since patch series "mm/damon: provide pseudo-moving sum based access
rate", which starts from commit 78fbfb155d ("mm/damon/core: define and
use a dedicated function for region access rate update"), DAMON provides
good-to-use quality moitoring results for every sampling interval. It
aims to help users who need to quickly retrieve the monitoring results.
When the aggregation interval is set too long and therefore waiting for
the aggregation interval can degrade user experience, or when the access
pattern is expected to be significantly changed[1] could be such cases.
However, because DAMON sysfs interface is still handling the commands per
aggregation interval, the end user cannot get the benefit. Update DAMON
sysfs interface to handle kdamond commands for every sampling interval if
applicable. Specifically, all kdamond data accessing commands except
'commit' command are applicable.
[1] https://lore.kernel.org/r/20240129121316.GA9706@cuiyangpei
Link: https://lkml.kernel.org/r/20240206025158.203097-1-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: xiongping1 <xiongping1@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
alloc_and_dissolve_hugetlb_folio() preallocates a new hugetlb page before
it takes hugetlb_lock. In 3 out of 4 cases the page is not really used
and therefore the newly allocated page is just freed right away. This is
wasteful and it might cause pre-mature failures in those cases.
Address that by moving the allocation down to the only case (hugetlb page
is really in the free pages pool). We need to drop hugetlb_lock to do so
and therefore need to recheck the page state after regaining it.
The patch is more of a cleanup than an actual fix to an existing problem.
There are no known reports about pre-mature failures.
Link: https://lkml.kernel.org/r/62890fd60b1ecd5bf1cdc476c973f60fe37aa0cb.1707181934.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pte_mkdirty() sets both _PAGE_DIRTY and _PAGE_SOFT_DIRTY bits. The
_PAGE_SOFT_DIRTY can get set even if it wasn't set on original page before
migration. This makes non-soft-dirty pages soft-dirty just because of
migration/compaction. Clear the _PAGE_SOFT_DIRTY flag if it wasn't set on
original page.
By definition of soft-dirty feature, there can be spurious soft-dirty
pages because of kernel's internal activity such as VMA merging or
migration/compaction. This patch is eliminating the spurious soft-dirty
pages because of migration/compaction.
Link: https://lkml.kernel.org/r/20240206084838.34560-1-usama.anjum@collabora.com
Signed-off-by: Paul Gofman <pgofman@codeweavers.com>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Andrei Vagin <avagin@gmail.com>
Cc: Michał Mirosław <emmir@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since we don't need to leave zswap entry on the zswap tree anymore,
we should remove it from tree once we find it from the tree.
Then after using it, we can directly free it, no concurrent path
can find it from tree. Only the shrinker can see it from lru list,
which will also double check under tree lock, so no race problem.
So we don't need refcount in zswap entry anymore and don't need to
take the spinlock for the second time to invalidate it.
The side effect is that zswap_entry_free() maybe not happen in tree
spinlock, but it's ok since nothing need to be protected by the lock.
Link: https://lkml.kernel.org/r/20240201-b4-zswap-invalidate-entry-v2-6-99d4084260a0@bytedance.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
