Merge changes related to system sleep and runtime PM framework for
6.18-rc1:
- Annotate loops walking device links in the power management core
code as _srcu and add macros for walking device links to reduce the
likelihood of coding mistakes related to them (Rafael Wysocki)
- Document time units for *_time functions in the runtime PM API (Brian
Norris)
- Clear power.must_resume in noirq suspend error path to avoid resuming
a dependant device under a suspended parent or supplier (Rafael
Wysocki)
- Fix GFP mask handling during hybrid suspend and make the amdgpu
driver handle hybrid suspend correctly (Mario Limonciello, Rafael
Wysocki)
- Fix GFP mask handling after aborted hibernation in platform mode and
combine exit paths in power_down() to avoid code duplication (Rafael
Wysocki)
- Use vmalloc_array() and vcalloc() in the hibernation core to avoid
open-coded size computations (Qianfeng Rong)
- Fix typo in hibernation core code comment (Li Jun)
- Call pm_wakeup_clear() in the same place where other functions that do
bookkeeping prior to suspend_prepare() are called (Samuel Wu)
* pm-core:
PM: core: Add two macros for walking device links
PM: core: Annotate loops walking device links as _srcu
* pm-runtime:
PM: runtime: Documentation: ABI: Document time units for *_time
* pm-sleep:
PM: hibernate: Combine return paths in power_down()
PM: hibernate: Restrict GFP mask in power_down()
PM: hibernate: Fix pm_hibernation_mode_is_suspend() build breakage
drm/amd: Fix hybrid sleep
PM: hibernate: Add pm_hibernation_mode_is_suspend()
PM: hibernate: Fix hybrid-sleep
PM: sleep: core: Clear power.must_resume in noirq suspend error path
PM: sleep: Make pm_wakeup_clear() call more clear
PM: hibernate: Fix typo in memory bitmaps description comment
PM: hibernate: Use vmalloc_array() and vcalloc() to improve code
Merge cpuidle and power capping changes for 6.18-rc1:
- Fail cpuidle device registration if there is one already to avoid
sysfs-related issues (Rafael Wysocki)
- Use sysfs_emit()/sysfs_emit_at() instead of sprintf()/scnprintf() in
cpuidle (Vivek Yadav)
- Fix device and OF node leaks at probe in the qcom-spm cpuidle driver
and drop unnecessary initialisations from it (Johan Hovold)
- Remove unnecessary address-of operators from the intel_idle cpuidle
driver (Kaushlendra Kumar)
- Rearrange main loop in menu_select() to make the code in that funtion
easier to follow (Rafael Wysocki)
- Convert values in microseconds to ktime using us_to_ktime() where
applicable in the intel_idle power capping driver (Xichao Zhao)
* pm-cpuidle:
cpuidle: Fail cpuidle device registration if there is one already
cpuidle: sysfs: Use sysfs_emit()/sysfs_emit_at() instead of sprintf()/scnprintf()
cpuidle: qcom-spm: drop unnecessary initialisations
cpuidle: qcom-spm: fix device and OF node leaks at probe
intel_idle: Remove unnecessary address-of operators
cpuidle: governors: menu: Rearrange main loop in menu_select()
* pm-powercap:
powercap: idle_inject: use us_to_ktime() where appropriate
Merge energy model management, OPP (operating performance points) and
devfreq updates for 6.18-rc1:
- Prevent CPU capacity updates after registering a perf domain from
failing on a first CPU that is not present (Christian Loehle)
- Add support for the cases in which frequency alone is not sufficient
to uniquely identify an OPP (Krishna Chaitanya Chundru)
- Use to_result() for OPP error handling in Rust (Onur Özkan)
- Add support for LPDDR5 on Rockhip RK3588 SoC to rockchip-dfi devfreq
driver (Nicolas Frattaroli)
- Fix an issue where DDR cycle counts on RK3588/RK3528 with LPDDR4(X)
are reported as half by adding a cycle multiplier to the DFI driver
in rockchip-dfi devfreq-event driver (Nicolas Frattaroli)
- Fix missing error pointer dereference check of regulator instance in
the mtk-cci devfreq driver probe and remove a redundant condition from
an if () statement in that driver (Dan Carpenter, Liao Yuanhong)
* pm-em:
PM: EM: Fix late boot with holes in CPU topology
* pm-opp:
OPP: Add support to find OPP for a set of keys
rust: opp: use to_result for error handling
* pm-devfreq:
PM / devfreq: rockchip-dfi: add support for LPDDR5
PM / devfreq: rockchip-dfi: double count on RK3588
PM / devfreq: mtk-cci: avoid redundant conditions
PM / devfreq: mtk-cci: Fix potential error pointer dereference in probe()
During initialization, the EDVD_COREx_VOLT_FREQ registers for some cores
are still at reset values and not reflecting the actual frequency. This
causes get calls to fail. Set all cores to their respective max
frequency during probe to initialize the registers to working values.
Suggested-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The original commit set all cores in a cluster to a shared policy, but
did not update set_target to apply a frequency change to all cores for
the policy. This caused most cores to remain stuck at their boot
frequency.
Fixes: be4ae8c194 ("cpufreq: tegra186: Share policy per cluster")
Signed-off-by: Aaron Kling <webgeek1234@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Remove local variables from find_supply_names() and use .and_then() with
the more concise kernel::kvec![] macro, instead of KVec::with_capacity()
followed by .push() and Some().
No functional changes intended.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Merge cpupower utility updates for 6.18-rc1 from Shuah Khan:
"Fixes incorrect return vale in cpupower_write_sysfs() error path
and passing incorrect size to cpuidle_state_write_file() while
writing status to disable file in cpuidle_state_disable()."
* tag 'linux-cpupower-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux: (1125 commits)
tools/cpupower: Fix incorrect size in cpuidle_state_disable()
tools/cpupower: fix error return value in cpupower_write_sysfs()
Linux 6.17-rc6
MAINTAINERS: Input: Drop melfas-mip4 section
USB: core: remove the move buf action
MAINTAINERS: Update the DMA Rust entry
erofs: fix long xattr name prefix placement
Revert "net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups"
hsr: hold rcu and dev lock for hsr_get_port_ndev
hsr: use hsr_for_each_port_rtnl in hsr_port_get_hsr
hsr: use rtnl lock when iterating over ports
wifi: nl80211: completely disable per-link stats for now
net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups
net: ethtool: fix wrong type used in struct kernel_ethtool_ts_info
selftests/bpf: Skip timer cases when bpf_timer is not supported
bpf: Reject bpf_timer for PREEMPT_RT
libceph: fix invalid accesses to ceph_connection_v1_info
PM: hibernate: Restrict GFP mask in hibernation_snapshot()
MAINTAINERS: add Phil as netfilter reviewer
netfilter: nf_tables: restart set lookup on base_seq change
...
From the cover letter [1]:
This patch set introduces kmalloc_nolock() which is the next logical
step towards any context allocation necessary to remove bpf_mem_alloc
and get rid of preallocation requirement in BPF infrastructure.
In production BPF maps grew to gigabytes in size. Preallocation wastes
memory. Alloc from any context addresses this issue for BPF and other
subsystems that are forced to preallocate too.
This long task started with introduction of alloc_pages_nolock(), then
memcg and objcg were converted to operate from any context including
NMI, this set completes the task with kmalloc_nolock() that builds on
top of alloc_pages_nolock() and memcg changes.
After that BPF subsystem will gradually adopt it everywhere.
Link: https://lore.kernel.org/all/20250909010007.1660-1-alexei.starovoitov@gmail.com/ [1]
This series adds an opt-in percpu array-based caching layer to SLUB.
It has evolved to a state where kmem caches with sheaves are compatible
with all SLUB features (slub_debug, SLUB_TINY, NUMA locality
considerations). The plan is therefore that it will be later enabled for
all kmem caches and replace the complicated cpu (partial) slabs code.
Note the name "sheaf" was invented by Matthew Wilcox so we don't call
the arrays magazines like the original Bonwick paper. The per-NUMA-node
cache of sheaves is thus called "barn".
This caching may seem similar to the arrays we had in SLAB, but there
are some important differences:
- deals differently with NUMA locality of freed objects, thus there are
no per-node "shared" arrays (with possible lock contention) and no
"alien" arrays that would need periodical flushing
- instead, freeing remote objects (which is rare) bypasses the sheaves
- percpu sheaves thus contain only local objects (modulo rare races
and local node exhaustion)
- NUMA restricted allocations and strict_numa mode is still honoured
- improves kfree_rcu() handling by reusing whole sheaves
- there is an API for obtaining a preallocated sheaf that can be used
for guaranteed and efficient allocations in a restricted context, when
the upper bound for needed objects is known but rarely reached
- opt-in, not used for every cache (for now)
The motivation comes mainly from the ongoing work related to VMA locking
scalability and the related maple tree operations. This is why VMA and
maple nodes caches are sheaf-enabled in the patchset.
A sheaf-enabled cache has the following expected advantages:
- Cheaper fast paths. For allocations, instead of local double cmpxchg,
thanks to local_trylock() it becomes a preempt_disable() and no atomic
operations. Same for freeing, which is otherwise a local double cmpxchg
only for short term allocations (so the same slab is still active on the
same cpu when freeing the object) and a more costly locked double
cmpxchg otherwise.
- kfree_rcu() batching and recycling. kfree_rcu() will put objects to a
separate percpu sheaf and only submit the whole sheaf to call_rcu()
when full. After the grace period, the sheaf can be used for
allocations, which is more efficient than freeing and reallocating
individual slab objects (even with the batching done by kfree_rcu()
implementation itself). In case only some cpus are allowed to handle rcu
callbacks, the sheaf can still be made available to other cpus on the
same node via the shared barn. The maple_node cache uses kfree_rcu() and
thus can benefit from this.
Note: this path is currently limited to !PREEMPT_RT
- Preallocation support. A prefilled sheaf can be privately borrowed to
perform a short term operation that is not allowed to block in the
middle and may need to allocate some objects. If an upper bound (worst
case) for the number of allocations is known, but only much fewer
allocations actually needed on average, borrowing and returning a sheaf
is much more efficient then a bulk allocation for the worst case
followed by a bulk free of the many unused objects. Maple tree write
operations should benefit from this.
- Compatibility with slub_debug. When slub_debug is enabled for a cache,
we simply don't create the percpu sheaves so that the debugging hooks
(at the node partial list slowpaths) are reached as before. The same
thing is done for CONFIG_SLUB_TINY. Sheaf preallocation still works by
reusing the (ineffective) paths for requests exceeding the cache's
sheaf_capacity. This is in line with the existing approach where
debugging bypasses the fast paths and SLUB_TINY preferes memory
savings over performance.
The above is adapted from the cover letter [1], which contains also
in-kernel microbenchmark results showing the lower overhead of sheaves.
Results from Suren Baghdasaryan [2] using a mmap/munmap microbenchmark
also show improvements.
Results from Sudarsan Mahendran [3] using will-it-scale show both
benefits and regressions, probably due to overall noisiness of those
tests.
Link: https://lore.kernel.org/all/20250910-slub-percpu-caches-v8-0-ca3099d8352c@suse.cz/ [1]
Link: https://lore.kernel.org/all/CAJuCfpEQ%3DRUgcAvRzE5jRrhhFpkm8E2PpBK9e9GhK26ZaJQt%3DQ@mail.gmail.com/ [2]
Link: https://lore.kernel.org/all/20250913000935.1021068-1-sudarsanm@google.com/ [3]
kmalloc_nolock() relies on ability of local_trylock_t to detect
the situation when per-cpu kmem_cache is locked.
In !PREEMPT_RT local_(try)lock_irqsave(&s->cpu_slab->lock, flags)
disables IRQs and marks s->cpu_slab->lock as acquired.
local_lock_is_locked(&s->cpu_slab->lock) returns true when
slab is in the middle of manipulating per-cpu cache
of that specific kmem_cache.
kmalloc_nolock() can be called from any context and can re-enter
into ___slab_alloc():
kmalloc() -> ___slab_alloc(cache_A) -> irqsave -> NMI -> bpf ->
kmalloc_nolock() -> ___slab_alloc(cache_B)
or
kmalloc() -> ___slab_alloc(cache_A) -> irqsave -> tracepoint/kprobe -> bpf ->
kmalloc_nolock() -> ___slab_alloc(cache_B)
Hence the caller of ___slab_alloc() checks if &s->cpu_slab->lock
can be acquired without a deadlock before invoking the function.
If that specific per-cpu kmem_cache is busy the kmalloc_nolock()
retries in a different kmalloc bucket. The second attempt will
likely succeed, since this cpu locked different kmem_cache.
Similarly, in PREEMPT_RT local_lock_is_locked() returns true when
per-cpu rt_spin_lock is locked by current _task_. In this case
re-entrance into the same kmalloc bucket is unsafe, and
kmalloc_nolock() tries a different bucket that is most likely is
not locked by the current task. Though it may be locked by a
different task it's safe to rt_spin_lock() and sleep on it.
Similar to alloc_pages_nolock() the kmalloc_nolock() returns NULL
immediately if called from hard irq or NMI in PREEMPT_RT.
kfree_nolock() defers freeing to irq_work when local_lock_is_locked()
and (in_nmi() or in PREEMPT_RT).
SLUB_TINY config doesn't use local_lock_is_locked() and relies on
spin_trylock_irqsave(&n->list_lock) to allocate,
while kfree_nolock() always defers to irq_work.
Note, kfree_nolock() must be called _only_ for objects allocated
with kmalloc_nolock(). Debug checks (like kmemleak and kfence)
were skipped on allocation, hence obj = kmalloc(); kfree_nolock(obj);
will miss kmemleak/kfence book keeping and will cause false positives.
large_kmalloc is not supported by either kmalloc_nolock()
or kfree_nolock().
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Since the combination of valid upper bits in slab->obj_exts with
OBJEXTS_ALLOC_FAIL bit can never happen,
use OBJEXTS_ALLOC_FAIL == (1ull << 0) as a magic sentinel
instead of (1ull << 2) to free up bit 2.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
kmalloc_nolock() can be called from any context
the ___slab_alloc() can acquire local_trylock_t (which is rt_spin_lock
in PREEMPT_RT) and attempt to acquire a different local_trylock_t
while in the same task context.
The calling sequence might look like:
kmalloc() -> tracepoint -> bpf -> kmalloc_nolock()
or more precisely:
__lock_acquire+0x12ad/0x2590
lock_acquire+0x133/0x2d0
rt_spin_lock+0x6f/0x250
___slab_alloc+0xb7/0xec0
kmalloc_nolock_noprof+0x15a/0x430
my_debug_callback+0x20e/0x390 [testmod]
___slab_alloc+0x256/0xec0
__kmalloc_cache_noprof+0xd6/0x3b0
Make LOCKDEP understand that local_trylock_t-s protect
different kmem_caches. In order to do that add lock_class_key
for each kmem_cache and use that key in local_trylock_t.
This stack trace is possible on both PREEMPT_RT and !PREEMPT_RT,
but teach lockdep about it only for PREEMPT_RT, since
in !PREEMPT_RT the ___slab_alloc() code is using
local_trylock_irqsave() when lockdep is on.
Note, this patch applies this logic to local_lock_t
while the next one converts it to local_trylock_t.
Both are mapped to rt_spin_lock in PREEMPT_RT.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Split alloc_pages_nolock() and introduce alloc_frozen_pages_nolock()
to be used by alloc_slab_page().
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Change alloc_pages_nolock() to default to __GFP_COMP when allocating
pages, since upcoming reentrant alloc_slab_page() needs __GFP_COMP.
Also allow __GFP_ACCOUNT flag to be specified,
since most of BPF infra needs __GFP_ACCOUNT except BPF streams.
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Introduce local_lock_is_locked() that returns true when
given local_lock is locked by current cpu (in !PREEMPT_RT) or
by current task (in PREEMPT_RT).
The goal is to detect a deadlock by the caller.
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Use the generic interface which should result in less bulk allocations
during a forking.
A part of this is to abstract the freeing of the sheaf or maple state
allocations into its own function so mas_destroy() and the tree
duplication code can use the same functionality to return any unused
resources.
[andriy.shevchenko@linux.intel.com: remove unused mt_alloc_bulk()]
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
The fast path through a write will require replacing a single node in
the tree. Using a sheaf (32 nodes) is too heavy for the fast path, so
special case the node store operation by just allocating one node in the
maple state.
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Use prefilled sheaves instead of bulk allocations. This should speed up
the allocations and the return path of unused allocations.
Remove the push and pop of nodes from the maple state as this is now
handled by the slab layer with sheaves.
Testing has been removed as necessary since the features of the tree
have been reduced.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Add the prefilled sheaf structs to the slab header and the associated
functions to the testing/shared/linux.c file.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
kfree() is a little shorter and works with kmem_cache_alloc'd pointers
too. Also lets us remove one more helper.
Signed-off-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
kfree_rcu is an optimized version of call_rcu + kfree. It used to not be
possible to call it on non-kmalloc objects, but this restriction was
lifted ever since SLOB was dropped from the kernel, and since commit
6c6c47b063 ("mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()").
Thus, replace call_rcu + mt_free_rcu with kfree_rcu.
Signed-off-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
There's some duplicated code and we are about to add more functionality
in maple-shared.h that we will need in the userspace maple test to be
available, so include it via maple-shim.c
Co-developed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Setup the maple_node_cache with percpu sheaves of size 32 to hopefully
improve its performance. Note this will not immediately take advantage
of sheaf batching of kfree_rcu() operations due to the maple tree using
call_rcu with custom callbacks. The followup changes to maple tree will
change that and also make use of the prefilled sheaves functionality.
Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Create the vm_area_struct cache with percpu sheaves of size 32 to
improve its performance.
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
The slab changes for sheaves requires more effort in the testing code.
Unite all the kmem_cache work into the tools/include slab header for
both the vma and maple tree testing.
The vma test code also requires importing more #defines to allow for
seamless use of the shared kmem_cache code.
This adds the pthread header to the slab header in the tools directory
to allow for the pthread_mutex in linux.c.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Currently allocations asking for a specific node explicitly or via
mempolicy in strict_numa node bypass percpu sheaves. Since sheaves
contain mostly local objects, we can try allocating from them if the
local node happens to be the requested node or allowed by the mempolicy.
If we find the object from percpu sheaves is not from the expected node,
we skip the sheaves - this should be rare.
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Add the reset of the ref count in vma_lock_init(). This is needed if
the vma memory is not zeroed on allocation.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Since we don't control the NUMA locality of objects in percpu sheaves,
allocations with node restrictions bypass them. Allocations without
restrictions may however still expect to get local objects with high
probability, and the introduction of sheaves can decrease it due to
freed object from a remote node ending up in percpu sheaves.
The fraction of such remote frees seems low (5% on an 8-node machine)
but it can be expected that some cache or workload specific corner cases
exist. We can either conclude that this is not a problem due to the low
fraction, or we can make remote frees bypass percpu sheaves and go
directly to their slabs. This will make the remote frees more expensive,
but if it's only a small fraction, most frees will still benefit from
the lower overhead of percpu sheaves.
This patch thus makes remote object freeing bypass percpu sheaves,
including bulk freeing, and kfree_rcu() via the rcu_free sheaf. However
it's not intended to be 100% guarantee that percpu sheaves will only
contain local objects. The refill from slabs does not provide that
guarantee in the first place, and there might be cpu migrations
happening when we need to unlock the local_lock. Avoiding all that could
be possible but complicated so we can leave it for later investigation
whether it would be worth it. It can be expected that the more selective
freeing will itself prevent accumulation of remote objects in percpu
sheaves so any such violations would have only short-term effects.
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Bulk insert mode was added to facilitate forking faster, but forking now
uses __mt_dup() to duplicate the tree.
The addition of sheaves has made the bulk allocations difficult to
maintain - since the expected entries would preallocate into the maple
state. A big part of the maple state node allocation was the ability to
push nodes back onto the state for later use, which was essential to the
bulk insert algorithm.
Remove mas_expected_entries() and mas_destroy_rebalance() functions as
well as the MA_STATE_BULK and MA_STATE_REBALANCE maple state flags since
there are no users anymore. Drop the associated testing as well.
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
The possibility of many barn operations is determined by the current
number of full or empty sheaves. Taking the barn->lock just to find out
that e.g. there are no empty sheaves results in unnecessary overhead and
lock contention. Thus perform these checks outside of the lock with a
data_race() annotated variable read and fail quickly without taking the
lock.
Checks for sheaf availability that racily succeed have to be obviously
repeated under the lock for correctness, but we can skip repeating
checks if there are too many sheaves on the given list as the limits
don't need to be strict.
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Add functions for efficient guaranteed allocations e.g. in a critical
section that cannot sleep, when the exact number of allocations is not
known beforehand, but an upper limit can be calculated.
kmem_cache_prefill_sheaf() returns a sheaf containing at least given
number of objects.
kmem_cache_alloc_from_sheaf() will allocate an object from the sheaf
and is guaranteed not to fail until depleted.
kmem_cache_return_sheaf() is for giving the sheaf back to the slab
allocator after the critical section. This will also attempt to refill
it to cache's sheaf capacity for better efficiency of sheaves handling,
but it's not stricly necessary to succeed.
kmem_cache_refill_sheaf() can be used to refill a previously obtained
sheaf to requested size. If the current size is sufficient, it does
nothing. If the requested size exceeds cache's sheaf_capacity and the
sheaf's current capacity, the sheaf will be replaced with a new one,
hence the indirect pointer parameter.
kmem_cache_sheaf_size() can be used to query the current size.
The implementation supports requesting sizes that exceed cache's
sheaf_capacity, but it is not efficient - such "oversize" sheaves are
allocated fresh in kmem_cache_prefill_sheaf() and flushed and freed
immediately by kmem_cache_return_sheaf(). kmem_cache_refill_sheaf()
might be especially ineffective when replacing a sheaf with a new one of
a larger capacity. It is therefore better to size cache's
sheaf_capacity accordingly to make oversize sheaves exceptional.
CONFIG_SLUB_STATS counters are added for sheaf prefill and return
operations. A prefill or return is considered _fast when it is able to
grab or return a percpu spare sheaf (even if the sheaf needs a refill to
satisfy the request, as those should amortize over time), and _slow
otherwise (when the barn or even sheaf allocation/freeing has to be
involved). sheaf_prefill_oversize is provided to determine how many
prefills were oversize (counter for oversize returns is not necessary as
all oversize refills result in oversize returns).
When slub_debug is enabled for a cache with sheaves, no percpu sheaves
exist for it, but the prefill functionality is still provided simply by
all prefilled sheaves becoming oversize. If percpu sheaves are not
created for a cache due to not passing the sheaf_capacity argument on
cache creation, the prefills also work through oversize sheaves, but
there's a WARN_ON_ONCE() to indicate the omission.
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Extend the sheaf infrastructure for more efficient kfree_rcu() handling.
For caches with sheaves, on each cpu maintain a rcu_free sheaf in
addition to main and spare sheaves.
kfree_rcu() operations will try to put objects on this sheaf. Once full,
the sheaf is detached and submitted to call_rcu() with a handler that
will try to put it in the barn, or flush to slab pages using bulk free,
when the barn is full. Then a new empty sheaf must be obtained to put
more objects there.
It's possible that no free sheaves are available to use for a new
rcu_free sheaf, and the allocation in kfree_rcu() context can only use
GFP_NOWAIT and thus may fail. In that case, fall back to the existing
kfree_rcu() implementation.
Expected advantages:
- batching the kfree_rcu() operations, that could eventually replace the
existing batching
- sheaves can be reused for allocations via barn instead of being
flushed to slabs, which is more efficient
- this includes cases where only some cpus are allowed to process rcu
callbacks (CONFIG_RCU_NOCB_CPU)
Possible disadvantage:
- objects might be waiting for more than their grace period (it is
determined by the last object freed into the sheaf), increasing memory
usage - but the existing batching does that too.
Only implement this for CONFIG_KVFREE_RCU_BATCHED as the tiny
implementation favors smaller memory footprint over performance.
Also for now skip the usage of rcu sheaf for CONFIG_PREEMPT_RT as the
contexts where kfree_rcu() is called might not be compatible with taking
a barn spinlock or a GFP_NOWAIT allocation of a new sheaf taking a
spinlock - the current kfree_rcu() implementation avoids doing that.
Teach kvfree_rcu_barrier() to flush all rcu_free sheaves from all caches
that have them. This is not a cheap operation, but the barrier usage is
rare - currently kmem_cache_destroy() or on module unload.
Add CONFIG_SLUB_STATS counters free_rcu_sheaf and free_rcu_sheaf_fail to
count how many kfree_rcu() used the rcu_free sheaf successfully and how
many had to fall back to the existing implementation.
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
The probe function in the psxpad-spi driver calls spi_setup()
but fails to check its return value. If the SPI bus setup fails,
the driver will still load successfully, resulting in potential
error in later I/O operations.
Add a check for the return value of spi_setup() and return
an error on failure.
Fixes: 8be193c7b1 ("Input: add support for PlayStation 1/2 joypads connected via SPI")
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Struct ff_effect_compat is embedded twice inside
uinput_ff_upload_compat, contains internal padding. In particular, there
is a hole after struct ff_replay to satisfy alignment requirements for
the following union member. Without clearing the structure,
copy_to_user() may leak stack data to userspace.
Initialize ff_up_compat to zero before filling valid fields.
Fixes: 2d56f3a32c ("Input: refactor evdev 32bit compat to be shareable with uinput")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
Link: https://lore.kernel.org/r/20250928063737.74590-1-zhen.ni@easystack.cn
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The contents of arm/altera/socfpga-sdram-edac.txt are already covered by
edac/altr,socfpga-ecc-manager.yaml except for the "altr,sdram-edac"
compatible string. Add the compatible and drop the old .txt binding doc.
Acked-by: Matthew Gerlach <matthew.gerlach@altera.com>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
There is a mix of using spin_lock() and spin_lock_irq(), which
is confusing as IB_POLL_WORKQUEUE is used and no code would
be called from any interrupt. So using spin_lock() or even
mutexes would be ok.
But we'll soon share common code with the client, which uses
IB_POLL_SOFTIRQ.
And Documentation/kernel-hacking/locking.rst section
"Cheat Sheet For Locking" says:
- Otherwise (== data can be touched in an interrupt), use
spin_lock_irqsave() and
spin_unlock_irqrestore().
So in order to keep it simple and safe we use that version
now. It will help merging functions into common code and
have consistent locking in all cases.
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Rafael J. Wysocki
Aaron Kling
Thorsten Blum
Johan Hovold
Vlastimil Babka
Alexei Starovoitov
Liam R. Howlett
Pedro Falcato
Lorenzo Stoakes
Qianfeng Rong
Haotian Zhang
Zhen Ni
Lad Prabhakar
Rob Herring (Arm)
Stefan Metzmacher