Pull kthread updates from Frederic Weisbecker:
"Kthreads affinity follow either of 4 existing different patterns:
1) Per-CPU kthreads must stay affine to a single CPU and never
execute relevant code on any other CPU. This is currently handled
by smpboot code which takes care of CPU-hotplug operations.
Affinity here is a correctness constraint.
2) Some kthreads _have_ to be affine to a specific set of CPUs and
can't run anywhere else. The affinity is set through
kthread_bind_mask() and the subsystem takes care by itself to
handle CPU-hotplug operations. Affinity here is assumed to be a
correctness constraint.
3) Per-node kthreads _prefer_ to be affine to a specific NUMA node.
This is not a correctness constraint but merely a preference in
terms of memory locality. kswapd and kcompactd both fall into this
category. The affinity is set manually like for any other task and
CPU-hotplug is supposed to be handled by the relevant subsystem so
that the task is properly reaffined whenever a given CPU from the
node comes up. Also care should be taken so that the node affinity
doesn't cross isolated (nohz_full) cpumask boundaries.
4) Similar to the previous point except kthreads have a _preferred_
affinity different than a node. Both RCU boost kthreads and RCU
exp kworkers fall into this category as they refer to "RCU nodes"
from a distinctly distributed tree.
Currently the preferred affinity patterns (3 and 4) have at least 4
identified users, with more or less success when it comes to handle
CPU-hotplug operations and CPU isolation. Each of which do it in its
own ad-hoc way.
This is an infrastructure proposal to handle this with the following
API changes:
- kthread_create_on_node() automatically affines the created kthread
to its target node unless it has been set as per-cpu or bound with
kthread_bind[_mask]() before the first wake-up.
- kthread_affine_preferred() is a new function that can be called
right after kthread_create_on_node() to specify a preferred
affinity different than the specified node.
When the preferred affinity can't be applied because the possible
targets are offline or isolated (nohz_full), the kthread is affine to
the housekeeping CPUs (which means to all online CPUs most of the time
or only the non-nohz_full CPUs when nohz_full= is set).
kswapd, kcompactd, RCU boost kthreads and RCU exp kworkers have been
converted, along with a few old drivers.
Summary of the changes:
- Consolidate a bunch of ad-hoc implementations of
kthread_run_on_cpu()
- Introduce task_cpu_fallback_mask() that defines the default last
resort affinity of a task to become nohz_full aware
- Add some correctness check to ensure kthread_bind() is always
called before the first kthread wake up.
- Default affine kthread to its preferred node.
- Convert kswapd / kcompactd and remove their halfway working ad-hoc
affinity implementation
- Implement kthreads preferred affinity
- Unify kthread worker and kthread API's style
- Convert RCU kthreads to the new API and remove the ad-hoc affinity
implementation"
* tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks:
kthread: modify kernel-doc function name to match code
rcu: Use kthread preferred affinity for RCU exp kworkers
treewide: Introduce kthread_run_worker[_on_cpu]()
kthread: Unify kthread_create_on_cpu() and kthread_create_worker_on_cpu() automatic format
rcu: Use kthread preferred affinity for RCU boost
kthread: Implement preferred affinity
mm: Create/affine kswapd to its preferred node
mm: Create/affine kcompactd to its preferred node
kthread: Default affine kthread to its preferred NUMA node
kthread: Make sure kthread hasn't started while binding it
sched,arm64: Handle CPU isolation on last resort fallback rq selection
arm64: Exclude nohz_full CPUs from 32bits el0 support
lib: test_objpool: Use kthread_run_on_cpu()
kallsyms: Use kthread_run_on_cpu()
soc/qman: test: Use kthread_run_on_cpu()
arm/bL_switcher: Use kthread_run_on_cpu()
Pull drm updates from Dave Airlie:
"There are two external interactions of note, the msm tree pull in some
opp tree, hopefully the opp tree arrives from the same git tree
however it normally does.
There is also a new cgroup controller for device memory, that is used
by drm, so is merging through my tree. This will hopefully help open
up gpu cgroup usage a bit more and move us forward.
There is a new accelerator driver for the AMD XDNA Ryzen AI NPUs.
Then the usual xe/amdgpu/i915/msm leaders and lots of changes and
refactors across the board:
core:
- device memory cgroup controller added
- Remove driver date from drm_driver
- Add drm_printer based hex dumper
- drm memory stats docs update
- scheduler documentation improvements
new driver:
- amdxdna - Ryzen AI NPU support
connector:
- add a mutex to protect ELD
- make connector setup two-step
panels:
- Introduce backlight quirks infrastructure
- New panels: KDB KD116N2130B12, Tianma TM070JDHG34-00,
- Multi-Inno Technology MI1010Z1T-1CP11
bridge:
- ti-sn65dsi83: Add ti,lvds-vod-swing optional properties
- Provide default implementation of atomic_check for HDMI bridges
- it605: HDCP improvements, MCCS Support
xe:
- make OA buffer size configurable
- GuC capture fixes
- add ufence and g2h flushes
- restore system memory GGTT mappings
- ioctl fixes
- SRIOV PF scheduling priority
- allow fault injection
- lots of improvements/refactors
- Enable GuC's WA_DUAL_QUEUE for newer platforms
- IRQ related fixes and improvements
i915:
- More accurate engine busyness metrics with GuC submission
- Ensure partial BO segment offset never exceeds allowed max
- Flush GuC CT receive tasklet during reset preparation
- Some DG2 refactor to fix DG2 bugs when operating with certain CPUs
- Fix DG1 power gate sequence
- Enabling uncompressed 128b/132b UHBR SST
- Handle hdmi connector init failures, and no HDMI/DP cases
- More robust engine resets on Haswell and older
i915/xe display:
- HDCP fixes for Xe3Lpd
- New GSC FW ARL-H/ARL-U
- support 3 VDSC engines 12 slices
- MBUS joining sanitisation
- reconcile i915/xe display power mgmt
- Xe3Lpd fixes
- UHBR rates for Thunderbolt
amdgpu:
- DRM panic support
- track BO memory stats at runtime
- Fix max surface handling in DC
- Cleaner shader support for gfx10.3 dGPUs
- fix drm buddy trim handling
- SDMA engine reset updates
- Fix doorbell ttm cleanup
- RAS updates
- ISP updates
- SDMA queue reset support
- Rework DPM powergating interfaces
- Documentation updates and cleanups
- DCN 3.5 updates
- Use a pm notifier to more gracefully handle VRAM eviction on
suspend or hibernate
- Add debugfs interfaces for forcing scheduling to specific engine
instances
- GG 9.5 updates
- IH 4.4 updates
- Make missing optional firmware less noisy
- PSP 13.x updates
- SMU 13.x updates
- VCN 5.x updates
- JPEG 5.x updates
- GC 12.x updates
- DC FAMS updates
amdkfd:
- GG 9.5 updates
- Logging improvements
- Shader debugger fixes
- Trap handler cleanup
- Cleanup includes
- Eviction fence wq fix
msm:
- MDSS:
- properly described UBWC registers
- added SM6150 (aka QCS615) support
- DPU:
- added SM6150 (aka QCS615) support
- enabled wide planes if virtual planes are enabled (by using two
SSPPs for a single plane)
- added CWB hardware blocks support
- DSI:
- added SM6150 (aka QCS615) support
- GPU:
- Print GMU core fw version
- GMU bandwidth voting for a740 and a750
- Expose uche trap base via uapi
- UAPI error reporting
rcar-du:
- Add r8a779h0 Support
ivpu:
- Fix qemu crash when using passthrough
nouveau:
- expose GSP-RM logging buffers via debugfs
panfrost:
- Add MT8188 Mali-G57 MC3 support
rockchip:
- Gamma LUT support
hisilicon:
- new HIBMC support
virtio-gpu:
- convert to helpers
- add prime support for scanout buffers
v3d:
- Add DRM_IOCTL_V3D_PERFMON_SET_GLOBAL
vc4:
- Add support for BCM2712
vkms:
- line-per-line compositing algorithm to improve performance
zynqmp:
- Add DP audio support
mediatek:
- dp: Add sdp path reset
- dp: Support flexible length of DP calibration data
etnaviv:
- add fdinfo memory support
- add explicit reset handling"
* tag 'drm-next-2025-01-17' of https://gitlab.freedesktop.org/drm/kernel: (1070 commits)
drm/bridge: fix documentation for the hdmi_audio_prepare() callback
doc/cgroup: Fix title underline length
drm/doc: Include new drm-compute documentation
cgroup/dmem: Fix parameters documentation
cgroup/dmem: Select PAGE_COUNTER
kernel/cgroup: Remove the unused variable climit
drm/display: hdmi: Do not read EDID on disconnected connectors
drm/tests: hdmi: Add connector disablement test
drm/connector: hdmi: Do atomic check when necessary
drm/amd/display: 3.2.316
drm/amd/display: avoid reset DTBCLK at clock init
drm/amd/display: improve dpia pre-train
drm/amd/display: Apply DML21 Patches
drm/amd/display: Use HW lock mgr for PSR1
drm/amd/display: Revised for Replay Pseudo vblank control
drm/amd/display: Add a new flag for replay low hz
drm/amd/display: Remove unused read_ono_state function from Hwss module
drm/amd/display: Do not elevate mem_type change to full update
drm/amd/display: Do not wait for PSR disable on vbl enable
drm/amd/display: Remove unnecessary eDP power down
...
Pull ftrace updates from Steven Rostedt:
- Have fprobes built on top of function graph infrastructure
The fprobe logic is an optimized kprobe that uses ftrace to attach to
functions when a probe is needed at the start or end of the function.
The fprobe and kretprobe logic implements a similar method as the
function graph tracer to trace the end of the function. That is to
hijack the return address and jump to a trampoline to do the trace
when the function exits. To do this, a shadow stack needs to be
created to store the original return address. Fprobes and function
graph do this slightly differently. Fprobes (and kretprobes) has
slots per callsite that are reserved to save the return address. This
is fine when just a few points are traced. But users of fprobes, such
as BPF programs, are starting to add many more locations, and this
method does not scale.
The function graph tracer was created to trace all functions in the
kernel. In order to do this, when function graph tracing is started,
every task gets its own shadow stack to hold the return address that
is going to be traced. The function graph tracer has been updated to
allow multiple users to use its infrastructure. Now have fprobes be
one of those users. This will also allow for the fprobe and kretprobe
methods to trace the return address to become obsolete. With new
technologies like CFI that need to know about these methods of
hijacking the return address, going toward a solution that has only
one method of doing this will make the kernel less complex.
- Cleanup with guard() and free() helpers
There were several places in the code that had a lot of "goto out" in
the error paths to either unlock a lock or free some memory that was
allocated. But this is error prone. Convert the code over to use the
guard() and free() helpers that let the compiler unlock locks or free
memory when the function exits.
- Remove disabling of interrupts in the function graph tracer
When function graph tracer was first introduced, it could race with
interrupts and NMIs. To prevent that race, it would disable
interrupts and not trace NMIs. But the code has changed to allow NMIs
and also interrupts. This change was done a long time ago, but the
disabling of interrupts was never removed. Remove the disabling of
interrupts in the function graph tracer is it is not needed. This
greatly improves its performance.
- Allow the :mod: command to enable tracing module functions on the
kernel command line.
The function tracer already has a way to enable functions to be
traced in modules by writing ":mod:<module>" into set_ftrace_filter.
That will enable either all the functions for the module if it is
loaded, or if it is not, it will cache that command, and when the
module is loaded that matches <module>, its functions will be
enabled. This also allows init functions to be traced. But currently
events do not have that feature.
Because enabling function tracing can be done very early at boot up
(before scheduling is enabled), the commands that can be done when
function tracing is started is limited. Having the ":mod:" command to
trace module functions as they are loaded is very useful. Update the
kernel command line function filtering to allow it.
* tag 'ftrace-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (26 commits)
ftrace: Implement :mod: cache filtering on kernel command line
tracing: Adopt __free() and guard() for trace_fprobe.c
bpf: Use ftrace_get_symaddr() for kprobe_multi probes
ftrace: Add ftrace_get_symaddr to convert fentry_ip to symaddr
Documentation: probes: Update fprobe on function-graph tracer
selftests/ftrace: Add a test case for repeating register/unregister fprobe
selftests: ftrace: Remove obsolate maxactive syntax check
tracing/fprobe: Remove nr_maxactive from fprobe
fprobe: Add fprobe_header encoding feature
fprobe: Rewrite fprobe on function-graph tracer
s390/tracing: Enable HAVE_FTRACE_GRAPH_FUNC
ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC
bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled
tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS
tracing: Add ftrace_fill_perf_regs() for perf event
tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs
fprobe: Use ftrace_regs in fprobe exit handler
fprobe: Use ftrace_regs in fprobe entry handler
fgraph: Pass ftrace_regs to retfunc
fgraph: Replace fgraph_ret_regs with ftrace_regs
...
Pull locking updates from Ingo Molnar:
"Lockdep:
- Improve and fix lockdep bitsize limits, clarify the Kconfig
documentation (Carlos Llamas)
- Fix lockdep build warning on Clang related to
chain_hlock_class_idx() inlining (Andy Shevchenko)
- Relax the requirements of PROVE_RAW_LOCK_NESTING arch support by
not tying it to ARCH_SUPPORTS_RT unnecessarily (Waiman Long)
Rust integration:
- Support lock pointers managed by the C side (Lyude Paul)
- Support guard types (Lyude Paul)
- Update MAINTAINERS file filters to include the Rust locking code
(Boqun Feng)
Wake-queues:
- Add raw_spin_*wake() helpers to simplify locking code (John Stultz)
SMP cross-calls:
- Fix potential data update race by evaluating the local cond_func()
before IPI side-effects (Mathieu Desnoyers)
Guard primitives:
- Ease [c]tags based searches by including the cleanup/guard type
primitives (Peter Zijlstra)
ww_mutexes:
- Simplify the ww_mutex self-test code via swap() (Thorsten Blum)
Static calls:
- Update the static calls MAINTAINERS file-pattern (Jiri Slaby)"
* tag 'locking-core-2025-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
MAINTAINERS: Add static_call_inline.c to STATIC BRANCH/CALL
cleanup, tags: Create tags for the cleanup primitives
sched/wake_q: Add helper to call wake_up_q after unlock with preemption disabled
rust: sync: Add lock::Backend::assert_is_held()
rust: sync: Add SpinLockGuard type alias
rust: sync: Add MutexGuard type alias
rust: sync: Make Guard::new() public
rust: sync: Add Lock::from_raw() for Lock<(), B>
locking: MAINTAINERS: Start watching Rust locking primitives
lockdep: Move lockdep_assert_locked() under #ifdef CONFIG_PROVE_LOCKING
lockdep: Mark chain_hlock_class_idx() with __maybe_unused
lockdep: Document MAX_LOCKDEP_CHAIN_HLOCKS calculation
lockdep: Clarify size for LOCKDEP_*_BITS configs
lockdep: Fix upper limit for LOCKDEP_*_BITS configs
locking/ww_mutex/test: Use swap() macro
smp/scf: Evaluate local cond_func() before IPI side-effects
locking/lockdep: Enforce PROVE_RAW_LOCK_NESTING only if ARCH_SUPPORTS_RT
Pull misc vfs updates from Christian Brauner:
"Features:
- Support caching symlink lengths in inodes
The size is stored in a new union utilizing the same space as
i_devices, thus avoiding growing the struct or taking up any more
space
When utilized it dodges strlen() in vfs_readlink(), giving about
1.5% speed up when issuing readlink on /initrd.img on ext4
- Add RWF_DONTCACHE iocb and FOP_DONTCACHE file_operations flag
If a file system supports uncached buffered IO, it may set
FOP_DONTCACHE and enable support for RWF_DONTCACHE.
If RWF_DONTCACHE is attempted without the file system supporting
it, it'll get errored with -EOPNOTSUPP
- Enable VBOXGUEST and VBOXSF_FS on ARM64
Now that VirtualBox is able to run as a host on arm64 (e.g. the
Apple M3 processors) we can enable VBOXSF_FS (and in turn
VBOXGUEST) for this architecture.
Tested with various runs of bonnie++ and dbench on an Apple MacBook
Pro with the latest Virtualbox 7.1.4 r165100 installed
Cleanups:
- Delay sysctl_nr_open check in expand_files()
- Use kernel-doc includes in fiemap docbook
- Use page->private instead of page->index in watch_queue
- Use a consume fence in mnt_idmap() as it's heavily used in
link_path_walk()
- Replace magic number 7 with ARRAY_SIZE() in fc_log
- Sort out a stale comment about races between fd alloc and dup2()
- Fix return type of do_mount() from long to int
- Various cosmetic cleanups for the lockref code
Fixes:
- Annotate spinning as unlikely() in __read_seqcount_begin
The annotation already used to be there, but got lost in commit
52ac39e5db ("seqlock: seqcount_t: Implement all read APIs as
statement expressions")
- Fix proc_handler for sysctl_nr_open
- Flush delayed work in delayed fput()
- Fix grammar and spelling in propagate_umount()
- Fix ESP not readable during coredump
In /proc/PID/stat, there is the kstkesp field which is the stack
pointer of a thread. While the thread is active, this field reads
zero. But during a coredump, it should have a valid value
However, at the moment, kstkesp is zero even during coredump
- Don't wake up the writer if the pipe is still full
- Fix unbalanced user_access_end() in select code"
* tag 'vfs-6.14-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
gfs2: use lockref_init for qd_lockref
erofs: use lockref_init for pcl->lockref
dcache: use lockref_init for d_lockref
lockref: add a lockref_init helper
lockref: drop superfluous externs
lockref: use bool for false/true returns
lockref: improve the lockref_get_not_zero description
lockref: remove lockref_put_not_zero
fs: Fix return type of do_mount() from long to int
select: Fix unbalanced user_access_end()
vbox: Enable VBOXGUEST and VBOXSF_FS on ARM64
pipe_read: don't wake up the writer if the pipe is still full
selftests: coredump: Add stackdump test
fs/proc: do_task_stat: Fix ESP not readable during coredump
fs: add RWF_DONTCACHE iocb and FOP_DONTCACHE file_operations flag
fs: sort out a stale comment about races between fd alloc and dup2
fs: Fix grammar and spelling in propagate_umount()
fs: fc_log replace magic number 7 with ARRAY_SIZE()
fs: use a consume fence in mnt_idmap()
file: flush delayed work in delayed fput()
...
Pull vfs netfs updates from Christian Brauner:
"This contains read performance improvements and support for monolithic
single-blob objects that have to be read/written as such (e.g. AFS
directory contents). The implementation of the two parts is interwoven
as each makes the other possible.
- Read performance improvements
The read performance improvements are intended to speed up some
loss of performance detected in cifs and to a lesser extend in afs.
The problem is that we queue too many work items during the
collection of read results: each individual subrequest is collected
by its own work item, and then they have to interact with each
other when a series of subrequests don't exactly align with the
pattern of folios that are being read by the overall request.
Whilst the processing of the pages covered by individual
subrequests as they complete potentially allows folios to be woken
in parallel and with minimum delay, it can shuffle wakeups for
sequential reads out of order - and that is the most common I/O
pattern.
The final assessment and cleanup of an operation is then held up
until the last I/O completes - and for a synchronous sequential
operation, this means the bouncing around of work items just adds
latency.
Two changes have been made to make this work:
(1) All collection is now done in a single "work item" that works
progressively through the subrequests as they complete (and
also dispatches retries as necessary).
(2) For readahead and AIO, this work item be done on a workqueue
and can run in parallel with the ultimate consumer of the data;
for synchronous direct or unbuffered reads, the collection is
run in the application thread and not offloaded.
Functions such as smb2_readv_callback() then just tell netfslib
that the subrequest has terminated; netfslib does a minimal bit of
processing on the spot - stat counting and tracing mostly - and
then queues/wakes up the worker. This simplifies the logic as the
collector just walks sequentially through the subrequests as they
complete and walks through the folios, if buffered, unlocking them
as it goes. It also keeps to a minimum the amount of latency
injected into the filesystem's low-level I/O handling
The way netfs supports filesystems using the deprecated
PG_private_2 flag is changed: folios are flagged and added to a
write request as they complete and that takes care of scheduling
the writes to the cache. The originating read request can then just
unlock the pages whatever happens.
- Single-blob object support
Single-blob objects are files for which the content of the file
must be read from or written to the server in a single operation
because reading them in parts may yield inconsistent results. AFS
directories are an example of this as there exists the possibility
that the contents are generated on the fly and would differ between
reads or might change due to third party interference.
Such objects will be written to and retrieved from the cache if one
is present, though we allow/may need to propose multiple
subrequests to do so. The important part is that read from/write to
the *server* is monolithic.
Single blob reading is, for the moment, fully synchronous and does
result collection in the application thread and, also for the
moment, the API is supplied the buffer in the form of a folio_queue
chain rather than using the pagecache.
- Related afs changes
This series makes a number of changes to the kafs filesystem,
primarily in the area of directory handling:
- AFS's FetchData RPC reply processing is made partially
asynchronous which allows the netfs_io_request's outstanding
operation counter to be removed as part of reducing the
collection to a single work item.
- Directory and symlink reading are plumbed through netfslib using
the single-blob object API and are now cacheable with fscache.
This also allows the afs_read struct to be eliminated and
netfs_io_subrequest to be used directly instead.
- Directory and symlink content are now stored in a folio_queue
buffer rather than in the pagecache. This means we don't require
the RCU read lock and xarray iteration to access it, and folios
won't randomly disappear under us because the VM wants them
back.
- The vnode operation lock is changed from a mutex struct to a
private lock implementation. The problem is that the lock now
needs to be dropped in a separate thread and mutexes don't
permit that.
- When a new directory or symlink is created, we now initialise it
locally and mark it valid rather than downloading it (we know
what it's likely to look like).
- We now use the in-directory hashtable to reduce the number of
entries we need to scan when doing a lookup. The edit routines
have to maintain the hash chains.
- Cancellation (e.g. by signal) of an async call after the
rxrpc_call has been set up is now offloaded to the worker thread
as there will be a notification from rxrpc upon completion. This
avoids a double cleanup.
- A "rolling buffer" implementation is created to abstract out the
two separate folio_queue chaining implementations I had (one for
read and one for write).
- Functions are provided to create/extend a buffer in a folio_queue
chain and tear it down again.
This is used to handle AFS directories, but could also be used to
create bounce buffers for content crypto and transport crypto.
- The was_async argument is dropped from netfs_read_subreq_terminated()
Instead we wake the read collection work item by either queuing it
or waking up the app thread.
- We don't need to use BH-excluding locks when communicating between
the issuing thread and the collection thread as neither of them now
run in BH context.
- Also included are a number of new tracepoints; a split of the
netfslib write collection code to put retrying into its own file
(it gets more complicated with content encryption).
- There are also some minor fixes AFS included, including fixing the
AFS directory format struct layout, reducing some directory
over-invalidation and making afs_mkdir() translate EEXIST to
ENOTEMPY (which is not available on all systems the servers
support).
- Finally, there's a patch to try and detect entry into the folio
unlock function with no folio_queue structs in the buffer (which
isn't allowed in the cases that can get there).
This is a debugging patch, but should be minimal overhead"
* tag 'vfs-6.14-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (31 commits)
netfs: Report on NULL folioq in netfs_writeback_unlock_folios()
afs: Add a tracepoint for afs_read_receive()
afs: Locally initialise the contents of a new symlink on creation
afs: Use the contained hashtable to search a directory
afs: Make afs_mkdir() locally initialise a new directory's content
netfs: Change the read result collector to only use one work item
afs: Make {Y,}FS.FetchData an asynchronous operation
afs: Fix cleanup of immediately failed async calls
afs: Eliminate afs_read
afs: Use netfslib for symlinks, allowing them to be cached
afs: Use netfslib for directories
afs: Make afs_init_request() get a key if not given a file
netfs: Add support for caching single monolithic objects such as AFS dirs
netfs: Add functions to build/clean a buffer in a folio_queue
afs: Add more tracepoints to do with tracking validity
cachefiles: Add auxiliary data trace
cachefiles: Add some subrequest tracepoints
netfs: Remove some extraneous directory invalidations
afs: Fix directory format encoding struct
afs: Fix EEXIST error returned from afs_rmdir() to be ENOTEMPTY
...
This merges the vsnprintf internal cleanups I did, which were triggered
by a combination of performance issues (see for example commit
f9ed1f7c2e: "genirq/proc: Use seq_put_decimal_ull_width() for decimal
values") and discussion about tracing abusing the vsnprintf code in odd
ways.
The intent was to improve code generation, but also to possibly
eventually expose the cleaned-up printf format decoding state machine.
It certainly didn't get to the point where we'd want to expose the
format decoding to external users, but it's an improvement over what we
used to have. Several of the complex case statements have been
simplified, or removed entirely to be replaced by simple table lookups.
* branch 'vsnprintf':
vsnprintf: fix the number base for non-numeric formats
vsnprintf: fix up kerneldoc for argument name changes
vsprintf: don't make the 'binary' version pack small integer arguments
vsnprintf: collapse the number format state into one single state
vsnprintf: mark the indirect width and precision cases unlikely
vsnprintf: inline skip_atoi() again
vsprintf: deal with format specifiers with a lookup table
vsprintf: deal with format flags with a simple lookup table
vsprintf: associate the format state with the format pointer
vsprintf: fix calling convention for format_decode()
vsprintf: avoid nested switch statement on same variable
vsprintf: simplify number handling
The test on whether rhashtable_insert_one did an insertion relies
on the value returned by rhashtable_lookup_one. Unfortunately that
value is overwritten after rhashtable_insert_one returns. Fix this
by moving the test before data gets overwritten.
Simplify the test as only data == NULL matters.
Finally move atomic_inc back within the lock as otherwise it may
be reordered with the atomic_dec on the removal side, potentially
leading to an underflow.
Reported-by: Michael Kelley <mhklinux@outlook.com>
Fixes: e1d3422c95 ("rhashtable: Fix potential deadlock by moving schedule_work outside lock")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Breno Leitao <leitao@debian.org>
Tested-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 8d4826cc8a ("vsnprintf: collapse the number format state into
one single state") changed the format specification decoding to be a bit
more straightforward but in the process ended up also resetting the
number base to zero for formats that aren't clearly numerical.
Now, the number base obviously doesn't matter for something like '%s',
so this wasn't all that obvious. But some of our specialized pointer
extension formatting (ie, things like "print out IPv6 address") did up
depending on the default base-10 setting, and when they then tried to
print out numbers in "base zero", things didn't work out so well.
Most pointer formatting (including things like the default raw hex value
conversion) didn't have this issue, because they used helpers that
explicitly set the base.
Reported-and-tested-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202501131352.e226f995-lkp@intel.com
Fixes: 8d4826cc8a ("vsnprintf: collapse the number format state into one single state")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need the IIO fixes in here as well, and it resolves a merge conflict
in:
drivers/iio/adc/ti-ads1119.c
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Patch series "xarray: extract __xa_cmpxchg_raw".
This series reduces duplication between __xa_cmpxchg and __xa_insert by
extracting a new function that does not coerce zero entries to null on the
return path.
The new function may be used by the upcoming Rust xarray abstraction in
its reservation API where it is useful to tell the difference between zero
entries and null slots.
This patch (of 2):
Reduce code duplication by extracting a static inline function that
returns its argument if it is non-zero and NULL otherwise.
This changes xas_result to check for errors before checking for zero but
this cannot change the behavior of existing callers:
- __xa_erase: passes the result of xas_store(_, NULL) which cannot fail.
- __xa_store: passes the result of xas_store(_, entry) which may fail.
xas_store calls xas_create when entry is not NULL which returns NULL
on error, which is immediately checked. This should not change
observable behavior.
- __xa_cmpxchg: passes the result of xas_load(_) which might be zero.
This would previously return NULL regardless of the outcome of
xas_store but xas_store cannot fail if xas_load returns zero
because there is no need to allocate memory.
- xa_store_range: same as __xa_erase.
Link: https://lkml.kernel.org/r/20241112-xarray-insert-cmpxchg-v1-0-dc2bdd8c4136@gmail.com
Link: https://lkml.kernel.org/r/20241112-xarray-insert-cmpxchg-v1-1-dc2bdd8c4136@gmail.com
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stephen Rothwell reports that I missed fixing up the documentation when
the argument names changed in commit 938df695e9 ("vsprintf: associate
the format state with the format pointer"), resulting in htmldoc
warnings like
lib/vsprintf.c:2760: warning: Function parameter or struct member 'fmt_str' not described in 'vsnprintf'
lib/vsprintf.c:2760: warning: Excess function parameter 'fmt' description in 'vsnprintf'
...
which I didn't notice because the doc build takes longer than the whole
"real" kernel build for me, so I never bother (and judging by the other
warnings, pretty much nobody else does either).
I guess the bigger issues won't be fixed until the doc build is much
faster (narrator: "That isn's in the cards") but at least linux-next
finds the new cases.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 938df695e9 ("vsprintf: associate the format state with the format pointer")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the LONG_MAX in simple_offset_add to 1024, and do latter:
[root@fedora ~]# mkdir /tmp/dir
[root@fedora ~]# for i in {1..1024}; do touch /tmp/dir/$i; done
touch: cannot touch '/tmp/dir/1024': Device or resource busy
[root@fedora ~]# rm /tmp/dir/123
[root@fedora ~]# touch /tmp/dir/1024
[root@fedora ~]# rm /tmp/dir/100
[root@fedora ~]# touch /tmp/dir/1025
touch: cannot touch '/tmp/dir/1025': Device or resource busy
After we delete file 100, actually this is a empty entry, but the latter
create failed unexpected.
mas_alloc_cyclic has two chance to find empty entry. First find the entry
with range range_lo and range_hi, if no empty entry exist, and range_lo >
min, retry find with range min and range_hi. However, the first call
mas_empty_area may mark mas as EBUSY, and the second call for
mas_empty_area will return false directly. Fix this by reload mas before
second call for mas_empty_area.
[Liam.Howlett@Oracle.com: fix mas_alloc_cyclic() second search]
Link: https://lore.kernel.org/all/20241216060600.287B4C4CED0@smtp.kernel.org/
Link: https://lkml.kernel.org/r/20241216190113.1226145-2-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20241214093005.72284-1-yangerkun@huaweicloud.com
Fixes: 9b6713cc75 ("maple_tree: Add mtree_alloc_cyclic()")
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com> says:
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The strange vbin_printf / bstr_printf interface used to save one- and
two-byte printf numerical arguments into their packed format.
That's more than a bit strange since the argument buffer is supposed to
be an array of 'u32' words, and it's also very different from how the
source of the data (varargs) work - which always do the normal integer
type conversions, so 'char' and 'short' are always passed as int-sized
anyway.
This odd packing causes extra code complexity, and it really isn't worth
it, since the space savings are simply not there: it only happens for
formats like '%hd' (short) and '%hhd' (char), which are very rare
indeed.
In fact, the only other user of this interface seems to be the bpf
helper code (bpf_bprintf_prepare()), and Alexei points out that that
case doesn't support those truncated integer formatting options at all
in the first place.
As a result, bpf_bprintf_prepare() doesn't need any changes for this,
and TRACE_BPRINT uses 'vbin_printf()' -> 'bstr_printf()' for the
formatting and hopefully doesn't expose the odd packing any other way
(knock wood).
Link: https://lore.kernel.org/all/CAADnVQJy65oOubjxM-378O3wDfhuwg8TGa9hc-cTv6NmmUSykQ@mail.gmail.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We'll squirrel away the size of the number in 'struct fmt' instead.
We have two fairly separate state structures: the 'decode state' is in
'struct fmt', while the 'printout format' is in 'printf_spec'. Both
structures are small enough to pass around in registers even across
function boundaries (ie two words), even on 32-bit machines.
The goal here is to avoid the case statements on the format states,
which generate either deep conditionals or jump tables, while also
keeping the state size manageable.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the format_decode() code generation easier to look at by getting
the strange and unlikely cases out of line.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At some point skip_atoi() had been marked 'noinline_for_stack', but it
turns out that this is now a pessimization, and not inlining it actually
results in a stack frame in format decoding due to the call and thus
hurts stack usage rather than helping.
With the simplistic atoi function inlined, the format decoding now needs
no frame at all.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We did the flags as an array earlier, they had simpler rules. The final
format specifiers are a bit more complex since they have more fields to
deal with, and we want to handle the length modifiers at the same time.
But like the flags, we're better off just making it a data-driven table
rather than some case statement.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
