kernel/linux.git/include/linux/cleanup.h, branch v7.0-rc7

cleanup: Make __DEFINE_LOCK_GUARD handle commas in initializers

2026-01-28T19:45:24+00:00

Initialization macros can expand to structure initializers containing commas, which when used as a "lock" function resulted in errors such as: >> include/linux/spinlock.h:582:56: error: too many arguments provided to function-like macro invocation 582 | DEFINE_LOCK_GUARD_1(raw_spinlock_init, raw_spinlock_t, raw_spin_lock_init(_T->lock), /* */) | ^ include/linux/spinlock.h:113:17: note: expanded from macro 'raw_spin_lock_init' 113 | do { *(lock) = __RAW_SPIN_LOCK_UNLOCKED(lock); } while (0) | ^ include/linux/spinlock_types_raw.h:70:19: note: expanded from macro '__RAW_SPIN_LOCK_UNLOCKED' 70 | (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname) | ^ include/linux/spinlock_types_raw.h:67:34: note: expanded from macro '__RAW_SPIN_LOCK_INITIALIZER' 67 | RAW_SPIN_DEP_MAP_INIT(lockname) } | ^ include/linux/cleanup.h:496:9: note: macro '__DEFINE_LOCK_GUARD_1' defined here 496 | #define __DEFINE_LOCK_GUARD_1(_name, _type, _lock) \ | ^ include/linux/spinlock.h:582:1: note: parentheses are required around macro argument containing braced initializer list 582 | DEFINE_LOCK_GUARD_1(raw_spinlock_init, raw_spinlock_t, raw_spin_lock_init(_T->lock), /* */) | ^ | ( include/linux/cleanup.h:558:60: note: expanded from macro 'DEFINE_LOCK_GUARD_1' 558 | __DEFINE_UNLOCK_GUARD(_name, _type, _unlock, __VA_ARGS__) \ | ^ Make __DEFINE_LOCK_GUARD_0 and __DEFINE_LOCK_GUARD_1 variadic so that __VA_ARGS__ captures everything. Reported-by: kernel test robot Signed-off-by: Marco Elver Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20260119094029.1344361-2-elver@google.com

cleanup: Basic compatibility with context analysis

2026-01-05T15:43:28+00:00

Introduce basic compatibility with cleanup.h infrastructure. We need to allow the compiler to see the acquisition and release of the context lock at the start and end of a scope. However, the current "cleanup" helpers wrap the lock in a struct passed through separate helper functions, which hides the lock alias from the compiler (no inter-procedural analysis). While Clang supports scoped guards in C++, it's not possible to apply in C code: https://clang.llvm.org/docs/ThreadSafetyAnalysis.html#scoped-context However, together with recent improvements to Clang's alias analysis abilities, idioms such as this work correctly now: void spin_unlock_cleanup(spinlock_t **l) __releases(*l) { .. } ... { spinlock_t *lock_scope __cleanup(spin_unlock_cleanup) = &lock; spin_lock(&lock); // lock through &lock ... critical section ... } // unlock through lock_scope -[alias]-> &lock (no warnings) To generalize this pattern and make it work with existing lock guards, introduce DECLARE_LOCK_GUARD_1_ATTRS() and WITH_LOCK_GUARD_1_ATTRS(). These allow creating an explicit alias to the context lock instance that is "cleaned" up with a separate cleanup helper. This helper is a dummy function that does nothing at runtime, but has the release attributes to tell the compiler what happens at the end of the scope. Example usage: DECLARE_LOCK_GUARD_1_ATTRS(mutex, __acquires(_T), __releases(*(struct mutex **)_T)) #define class_mutex_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(mutex, _T) Note: To support the for-loop based scoped helpers, the auxiliary variable must be a pointer to the "class" type because it is defined in the same statement as the guard variable. However, we initialize it with the lock pointer (despite the type mismatch, the compiler's alias analysis still works as expected). The "_unlock" attribute receives a pointer to the auxiliary variable (a double pointer to the class type), and must be cast and dereferenced appropriately. Signed-off-by: Marco Elver Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251219154418.3592607-7-elver@google.com

include/linux: change "__auto_type" to "auto"

2025-12-08T23:32:14+00:00

Replace instances of "__auto_type" with "auto" in include/linux. Signed-off-by: H. Peter Anvin (Intel)

Merge tag 'core-rseq-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T16:48:53+00:00

Pull rseq updates from Thomas Gleixner: "A large overhaul of the restartable sequences and CID management: The recent enablement of RSEQ in glibc resulted in regressions which are caused by the related overhead. It turned out that the decision to invoke the exit to user work was not really a decision. More or less each context switch caused that. There is a long list of small issues which sums up nicely and results in a 3-4% regression in I/O benchmarks. The other detail which caused issues due to extra work in context switch and task migration is the CID (memory context ID) management. It also requires to use a task work to consolidate the CID space, which is executed in the context of an arbitrary task and results in sporadic uncontrolled exit latencies. The rewrite addresses this by: - Removing deprecated and long unsupported functionality - Moving the related data into dedicated data structures which are optimized for fast path processing. - Caching values so actual decisions can be made - Replacing the current implementation with a optimized inlined variant. - Separating fast and slow path for architectures which use the generic entry code, so that only fault and error handling goes into the TIF_NOTIFY_RESUME handler. - Rewriting the CID management so that it becomes mostly invisible in the context switch path. That moves the work of switching modes into the fork/exit path, which is a reasonable tradeoff. That work is only required when a process creates more threads than the cpuset it is allowed to run on or when enough threads exit after that. An artificial thread pool benchmarks which triggers this did not degrade, it actually improved significantly. The main effect in migration heavy scenarios is that runqueue lock held time and therefore contention goes down significantly" * tag 'core-rseq-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits) sched/mmcid: Switch over to the new mechanism sched/mmcid: Implement deferred mode change irqwork: Move data struct to a types header sched/mmcid: Provide CID ownership mode fixup functions sched/mmcid: Provide new scheduler CID mechanism sched/mmcid: Introduce per task/CPU ownership infrastructure sched/mmcid: Serialize sched_mm_cid_fork()/exit() with a mutex sched/mmcid: Provide precomputed maximal value sched/mmcid: Move initialization out of line signal: Move MMCID exit out of sighand lock sched/mmcid: Convert mm CID mask to a bitmap cpumask: Cache num_possible_cpus() sched/mmcid: Use cpumask_weighted_or() cpumask: Introduce cpumask_weighted_or() sched/mmcid: Prevent pointless work in mm_update_cpus_allowed() sched/mmcid: Move scheduler code out of global header sched: Fixup whitespace damage sched/mmcid: Cacheline align MM CID storage sched/mmcid: Use proper data structures sched/mmcid: Revert the complex CID management ...

Merge tag 'sched-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T05:04:45+00:00

Pull scheduler updates from Ingo Molnar: "Scalability and load-balancing improvements: - Enable scheduler feature NEXT_BUDDY (Mel Gorman) - Reimplement NEXT_BUDDY to align with EEVDF goals (Mel Gorman) - Skip sched_balance_running cmpxchg when balance is not due (Tim Chen) - Implement generic code for architecture specific sched domain NUMA distances (Tim Chen) - Optimize the NUMA distances of the sched-domains builds of Intel Granite Rapids (GNR) and Clearwater Forest (CWF) platforms (Tim Chen) - Implement proportional newidle balance: a randomized algorithm that runs newidle balancing proportional to its success rate. (Peter Zijlstra) Scheduler infrastructure changes: - Implement the 'sched_change' scoped_guard() pattern for the entire scheduler (Peter Zijlstra) - More broadly utilize the sched_change guard (Peter Zijlstra) - Add support to pick functions to take runqueue-flags (Joel Fernandes) - Provide and use set_need_resched_current() (Peter Zijlstra) Fair scheduling enhancements: - Forfeit vruntime on yield (Fernand Sieber) - Only update stats for allowed CPUs when looking for dst group (Adam Li) CPU-core scheduling enhancements: - Optimize core cookie matching check (Fernand Sieber) Deadline scheduler fixes: - Only set free_cpus for online runqueues (Doug Berger) - Fix dl_server time accounting (Peter Zijlstra) - Fix dl_server stop condition (Peter Zijlstra) Proxy scheduling fixes: - Yield the donor task (Fernand Sieber) Fixes and cleanups: - Fix do_set_cpus_allowed() locking (Peter Zijlstra) - Fix migrate_disable_switch() locking (Peter Zijlstra) - Remove double update_rq_clock() in __set_cpus_allowed_ptr_locked() (Hao Jia) - Increase sched_tick_remote timeout (Phil Auld) - sched/deadline: Use cpumask_weight_and() in dl_bw_cpus() (Shrikanth Hegde) - sched/deadline: Clean up select_task_rq_dl() (Shrikanth Hegde)" * tag 'sched-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) sched: Provide and use set_need_resched_current() sched/fair: Proportional newidle balance sched/fair: Small cleanup to update_newidle_cost() sched/fair: Small cleanup to sched_balance_newidle() sched/fair: Revert max_newidle_lb_cost bump sched/fair: Reimplement NEXT_BUDDY to align with EEVDF goals sched/fair: Enable scheduler feature NEXT_BUDDY sched: Increase sched_tick_remote timeout sched/fair: Have SD_SERIALIZE affect newidle balancing sched/fair: Skip sched_balance_running cmpxchg when balance is not due sched/deadline: Minor cleanup in select_task_rq_dl() sched/deadline: Use cpumask_weight_and() in dl_bw_cpus sched/deadline: Document dl_server sched/deadline: Fix dl_server stop condition sched/deadline: Fix dl_server time accounting sched/core: Remove double update_rq_clock() in __set_cpus_allowed_ptr_locked() sched/eevdf: Fix min_vruntime vs avg_vruntime sched/core: Add comment explaining force-idle vruntime snapshots sched/core: Optimize core cookie matching check sched/proxy: Yield the donor task ...

Merge tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-02T01:32:07+00:00

Pull fd prepare updates from Christian Brauner: "This adds the FD_ADD() and FD_PREPARE() primitive. They simplify the common pattern of get_unused_fd_flags() + create file + fd_install() that is used extensively throughout the kernel and currently requires cumbersome cleanup paths. FD_ADD() - For simple cases where a file is installed immediately: fd = FD_ADD(O_CLOEXEC, vfio_device_open_file(device)); if (fd < 0) vfio_device_put_registration(device); return fd; FD_PREPARE() - For cases requiring access to the fd or file, or additional work before publishing: FD_PREPARE(fdf, O_CLOEXEC, sync_file->file); if (fdf.err) { fput(sync_file->file); return fdf.err; } data.fence = fd_prepare_fd(fdf); if (copy_to_user((void __user *)arg, &data, sizeof(data))) return -EFAULT; return fd_publish(fdf); The primitives are centered around struct fd_prepare. FD_PREPARE() encapsulates all allocation and cleanup logic and must be followed by a call to fd_publish() which associates the fd with the file and installs it into the caller's fdtable. If fd_publish() isn't called, both are deallocated automatically. FD_ADD() is a shorthand that does fd_publish() immediately and never exposes the struct to the caller. I've implemented this in a way that it's compatible with the cleanup infrastructure while also being usable separately. IOW, it's centered around struct fd_prepare which is aliased to class_fd_prepare_t and so we can make use of all the basica guard infrastructure" * tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits) io_uring: convert io_create_mock_file() to FD_PREPARE() file: convert replace_fd() to FD_PREPARE() vfio: convert vfio_group_ioctl_get_device_fd() to FD_ADD() tty: convert ptm_open_peer() to FD_ADD() ntsync: convert ntsync_obj_get_fd() to FD_PREPARE() media: convert media_request_alloc() to FD_PREPARE() hv: convert mshv_ioctl_create_partition() to FD_ADD() gpio: convert linehandle_create() to FD_PREPARE() pseries: port papr_rtas_setup_file_interface() to FD_ADD() pseries: convert papr_platform_dump_create_handle() to FD_ADD() spufs: convert spufs_gang_open() to FD_PREPARE() papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE() spufs: convert spufs_context_open() to FD_PREPARE() net/socket: convert __sys_accept4_file() to FD_ADD() net/socket: convert sock_map_fd() to FD_ADD() net/kcm: convert kcm_ioctl() to FD_PREPARE() net/handshake: convert handshake_nl_accept_doit() to FD_PREPARE() secretmem: convert memfd_secret() to FD_ADD() memfd: convert memfd_create() to FD_ADD() bpf: convert bpf_token_create() to FD_PREPARE() ...

file: add FD_{ADD,PREPARE}()

2025-11-28T11:42:23+00:00

I've been playing with this to allow for moderately flexible usage of the get_unused_fd_flags() + create file + fd_install() pattern that's used quite extensively. How callers allocate files is really heterogenous so it's not really convenient to fold them into a single class. It's possibe to split them into subclasses like for anon inodes. I think that's not necessarily nice as well. My take is to add two primites: (1) FD_ADD() the simple cases a file is installed: fd = FD_ADD(O_CLOEXEC, open_file(some, args))); if (fd >= 0) kvm_get_kvm(vcpu->kvm); return fd; (2) FD_PREPARE() that captures all the cases where access to fd or file or additional work before publishing the fd is needed: FD_PREPARE(fdf, open_flag, file_open_handle(&path, open_flag)); if (fdf.err) return fdf.err; if (copy_to_user(/* something something */)) return -EFAULT; return fd_publish(fdf); I've converted all of the easy cases over to it and it gets rid of an aweful lot of convoluted cleanup logic. It's centered around struct fd_prepare. FD_PREPARE() encapsulates all of allocation and cleanup logic and must be followed by a call to fd_publish() which associates the fd with the file and installs it into the callers fdtable. If fd_publish() isn't called both are deallocated. It mandates a specific order namely that first we allocate the fd and then instantiate the file. But that shouldn't be a problem nearly everyone I've converted uses this exact pattern anyway. There's a bunch of additional cases where it would be easy to convert them to this pattern. For example, the whole sync file stuff in dma currently retains the containing structure of the file instead of the file itself even though it's only used to allocate files. Changing that would make it fall into the FD_PREPARE() pattern easily. I've not done that work yet. There's room for extending this in a way that wed'd have subclasses for some particularly often use patterns but as I said I'm not even sure that's worth it. Link: https://patch.msgid.link/20251123-work-fd-prepare-v4-1-b6efa1706cfd@kernel.org Signed-off-by: Christian Brauner

cleanup: fix scoped_class()

2025-11-04T11:35:49+00:00

This is a class, not a guard so why on earth is it checking for guard pointers or conditional lock acquisition? None of it makes any sense at all. I'm not sure what happened back then. Maybe I had a brief psychedelic period that I completely forgot about and spaced out into a zone where that initial macro implementation made any sense at all. Link: https://patch.msgid.link/20251103-work-creds-init_cred-v1-1-cb3ec8711a6a@kernel.org Fixes: 5c21c5f22d07 ("cleanup: add a scoped version of CLASS()") Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner

cleanup: Always inline everything

2025-11-04T07:35:58+00:00

KASAN bloat caused cleanup helper functions to not get inlined: vmlinux.o: error: objtool: irqentry_exit+0x323: call to class_user_rw_access_destructor() with UACCESS enabled Force inline all the cleanup helpers like they already are on normal builds. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20251031105435.GU4068168@noisy.programming.kicks-ass.net

sched: Employ sched_change guards

2025-10-16T09:13:50+00:00

As proposed a long while ago -- and half done by scx -- wrap the scheduler's 'change' pattern in a guard helper. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Juri Lelli Acked-by: Tejun Heo Acked-by: Vincent Guittot