diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-02-10 12:28:44 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-02-10 12:28:44 -0800 |
| commit | 0923fd0419a1a2c8846e15deacac11b619e996d9 (patch) | |
| tree | 7cc5fecc1680f5881f1d4183be400b51c81e6943 /kernel/sched | |
| parent | 4d84667627c4ff70826b349c449bbaf63b9af4e5 (diff) | |
| parent | 7a562d5d2396c9c78fbbced7ae81bcfcfa0fde3f (diff) | |
Merge tag 'locking-core-2026-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
"Lock debugging:
- Implement compiler-driven static analysis locking context checking,
using the upcoming Clang 22 compiler's context analysis features
(Marco Elver)
We removed Sparse context analysis support, because prior to
removal even a defconfig kernel produced 1,700+ context tracking
Sparse warnings, the overwhelming majority of which are false
positives. On an allmodconfig kernel the number of false positive
context tracking Sparse warnings grows to over 5,200... On the plus
side of the balance actual locking bugs found by Sparse context
analysis is also rather ... sparse: I found only 3 such commits in
the last 3 years. So the rate of false positives and the
maintenance overhead is rather high and there appears to be no
active policy in place to achieve a zero-warnings baseline to move
the annotations & fixers to developers who introduce new code.
Clang context analysis is more complete and more aggressive in
trying to find bugs, at least in principle. Plus it has a different
model to enabling it: it's enabled subsystem by subsystem, which
results in zero warnings on all relevant kernel builds (as far as
our testing managed to cover it). Which allowed us to enable it by
default, similar to other compiler warnings, with the expectation
that there are no warnings going forward. This enforces a
zero-warnings baseline on clang-22+ builds (Which are still limited
in distribution, admittedly)
Hopefully the Clang approach can lead to a more maintainable
zero-warnings status quo and policy, with more and more subsystems
and drivers enabling the feature. Context tracking can be enabled
for all kernel code via WARN_CONTEXT_ANALYSIS_ALL=y (default
disabled), but this will generate a lot of false positives.
( Having said that, Sparse support could still be added back,
if anyone is interested - the removal patch is still
relatively straightforward to revert at this stage. )
Rust integration updates: (Alice Ryhl, Fujita Tomonori, Boqun Feng)
- Add support for Atomic<i8/i16/bool> and replace most Rust native
AtomicBool usages with Atomic<bool>
- Clean up LockClassKey and improve its documentation
- Add missing Send and Sync trait implementation for SetOnce
- Make ARef Unpin as it is supposed to be
- Add __rust_helper to a few Rust helpers as a preparation for
helper LTO
- Inline various lock related functions to avoid additional function
calls
WW mutexes:
- Extend ww_mutex tests and other test-ww_mutex updates (John
Stultz)
Misc fixes and cleanups:
- rcu: Mark lockdep_assert_rcu_helper() __always_inline (Arnd
Bergmann)
- locking/local_lock: Include more missing headers (Peter Zijlstra)
- seqlock: fix scoped_seqlock_read kernel-doc (Randy Dunlap)
- rust: sync: Replace `kernel::c_str!` with C-Strings (Tamir
Duberstein)"
* tag 'locking-core-2026-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (90 commits)
locking/rwlock: Fix write_trylock_irqsave() with CONFIG_INLINE_WRITE_TRYLOCK
rcu: Mark lockdep_assert_rcu_helper() __always_inline
compiler-context-analysis: Remove __assume_ctx_lock from initializers
tomoyo: Use scoped init guard
crypto: Use scoped init guard
kcov: Use scoped init guard
compiler-context-analysis: Introduce scoped init guards
cleanup: Make __DEFINE_LOCK_GUARD handle commas in initializers
seqlock: fix scoped_seqlock_read kernel-doc
tools: Update context analysis macros in compiler_types.h
rust: sync: Replace `kernel::c_str!` with C-Strings
rust: sync: Inline various lock related methods
rust: helpers: Move #define __rust_helper out of atomic.c
rust: wait: Add __rust_helper to helpers
rust: time: Add __rust_helper to helpers
rust: task: Add __rust_helper to helpers
rust: sync: Add __rust_helper to helpers
rust: refcount: Add __rust_helper to helpers
rust: rcu: Add __rust_helper to helpers
rust: processor: Add __rust_helper to helpers
...
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/Makefile | 3 | ||||
| -rw-r--r-- | kernel/sched/core.c | 89 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 7 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 126 |
4 files changed, 162 insertions, 63 deletions
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index 8ae86371ddcd..b1f1a367034f 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -1,5 +1,8 @@ # SPDX-License-Identifier: GPL-2.0 +CONTEXT_ANALYSIS_core.o := y +CONTEXT_ANALYSIS_fair.o := y + # The compilers are complaining about unused variables inside an if(0) scope # block. This is daft, shut them up. ccflags-y += $(call cc-disable-warning, unused-but-set-variable) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 854984967fe2..d78d7b6d30bb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -396,6 +396,8 @@ static atomic_t sched_core_count; static struct cpumask sched_core_mask; static void sched_core_lock(int cpu, unsigned long *flags) + __context_unsafe(/* acquires multiple */) + __acquires(&runqueues.__lock) /* overapproximation */ { const struct cpumask *smt_mask = cpu_smt_mask(cpu); int t, i = 0; @@ -406,6 +408,8 @@ static void sched_core_lock(int cpu, unsigned long *flags) } static void sched_core_unlock(int cpu, unsigned long *flags) + __context_unsafe(/* releases multiple */) + __releases(&runqueues.__lock) /* overapproximation */ { const struct cpumask *smt_mask = cpu_smt_mask(cpu); int t; @@ -630,6 +634,7 @@ EXPORT_SYMBOL(__trace_set_current_state); */ void raw_spin_rq_lock_nested(struct rq *rq, int subclass) + __context_unsafe() { raw_spinlock_t *lock; @@ -655,6 +660,7 @@ void raw_spin_rq_lock_nested(struct rq *rq, int subclass) } bool raw_spin_rq_trylock(struct rq *rq) + __context_unsafe() { raw_spinlock_t *lock; bool ret; @@ -696,15 +702,16 @@ void double_rq_lock(struct rq *rq1, struct rq *rq2) raw_spin_rq_lock(rq1); if (__rq_lockp(rq1) != __rq_lockp(rq2)) raw_spin_rq_lock_nested(rq2, SINGLE_DEPTH_NESTING); + else + __acquire_ctx_lock(__rq_lockp(rq2)); /* fake acquire */ double_rq_clock_clear_update(rq1, rq2); } /* - * __task_rq_lock - lock the rq @p resides on. + * ___task_rq_lock - lock the rq @p resides on. */ -struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(rq->lock) +struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) { struct rq *rq; @@ -727,9 +734,7 @@ struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) /* * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. */ -struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(p->pi_lock) - __acquires(rq->lock) +struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) { struct rq *rq; @@ -2431,6 +2436,7 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu) */ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf, struct task_struct *p, int new_cpu) + __must_hold(__rq_lockp(rq)) { lockdep_assert_rq_held(rq); @@ -2477,6 +2483,7 @@ struct set_affinity_pending { */ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf, struct task_struct *p, int dest_cpu) + __must_hold(__rq_lockp(rq)) { /* Affinity changed (again). */ if (!is_cpu_allowed(p, dest_cpu)) @@ -2513,6 +2520,12 @@ static int migration_cpu_stop(void *data) */ flush_smp_call_function_queue(); + /* + * We may change the underlying rq, but the locks held will + * appropriately be "transferred" when switching. + */ + context_unsafe_alias(rq); + raw_spin_lock(&p->pi_lock); rq_lock(rq, &rf); @@ -2624,6 +2637,8 @@ int push_cpu_stop(void *arg) if (!lowest_rq) goto out_unlock; + lockdep_assert_rq_held(lowest_rq); + // XXX validate p is still the highest prio task if (task_rq(p) == rq) { move_queued_task_locked(rq, lowest_rq, p); @@ -2834,8 +2849,7 @@ void release_user_cpus_ptr(struct task_struct *p) */ static int affine_move_task(struct rq *rq, struct task_struct *p, struct rq_flags *rf, int dest_cpu, unsigned int flags) - __releases(rq->lock) - __releases(p->pi_lock) + __releases(__rq_lockp(rq), &p->pi_lock) { struct set_affinity_pending my_pending = { }, *pending = NULL; bool stop_pending, complete = false; @@ -2990,8 +3004,7 @@ static int __set_cpus_allowed_ptr_locked(struct task_struct *p, struct affinity_context *ctx, struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) - __releases(p->pi_lock) + __releases(__rq_lockp(rq), &p->pi_lock) { const struct cpumask *cpu_allowed_mask = task_cpu_possible_mask(p); const struct cpumask *cpu_valid_mask = cpu_active_mask; @@ -4273,29 +4286,30 @@ static bool __task_needs_rq_lock(struct task_struct *p) */ int task_call_func(struct task_struct *p, task_call_f func, void *arg) { - struct rq *rq = NULL; struct rq_flags rf; int ret; raw_spin_lock_irqsave(&p->pi_lock, rf.flags); - if (__task_needs_rq_lock(p)) - rq = __task_rq_lock(p, &rf); + if (__task_needs_rq_lock(p)) { + struct rq *rq = __task_rq_lock(p, &rf); - /* - * At this point the task is pinned; either: - * - blocked and we're holding off wakeups (pi->lock) - * - woken, and we're holding off enqueue (rq->lock) - * - queued, and we're holding off schedule (rq->lock) - * - running, and we're holding off de-schedule (rq->lock) - * - * The called function (@func) can use: task_curr(), p->on_rq and - * p->__state to differentiate between these states. - */ - ret = func(p, arg); + /* + * At this point the task is pinned; either: + * - blocked and we're holding off wakeups (pi->lock) + * - woken, and we're holding off enqueue (rq->lock) + * - queued, and we're holding off schedule (rq->lock) + * - running, and we're holding off de-schedule (rq->lock) + * + * The called function (@func) can use: task_curr(), p->on_rq and + * p->__state to differentiate between these states. + */ + ret = func(p, arg); - if (rq) __task_rq_unlock(rq, p, &rf); + } else { + ret = func(p, arg); + } raw_spin_unlock_irqrestore(&p->pi_lock, rf.flags); return ret; @@ -4972,6 +4986,8 @@ void balance_callbacks(struct rq *rq, struct balance_callback *head) static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf) + __releases(__rq_lockp(rq)) + __acquires(__rq_lockp(this_rq())) { /* * Since the runqueue lock will be released by the next @@ -4985,9 +5001,15 @@ prepare_lock_switch(struct rq *rq, struct task_struct *next, struct rq_flags *rf /* this is a valid case when another task releases the spinlock */ rq_lockp(rq)->owner = next; #endif + /* + * Model the rq reference switcheroo. + */ + __release(__rq_lockp(rq)); + __acquire(__rq_lockp(this_rq())); } static inline void finish_lock_switch(struct rq *rq) + __releases(__rq_lockp(rq)) { /* * If we are tracking spinlock dependencies then we have to @@ -5043,6 +5065,7 @@ static inline void kmap_local_sched_in(void) static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) + __must_hold(__rq_lockp(rq)) { kcov_prepare_switch(prev); sched_info_switch(rq, prev, next); @@ -5073,7 +5096,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev, * because prev may have moved to another CPU. */ static struct rq *finish_task_switch(struct task_struct *prev) - __releases(rq->lock) + __releases(__rq_lockp(this_rq())) { struct rq *rq = this_rq(); struct mm_struct *mm = rq->prev_mm; @@ -5169,7 +5192,7 @@ static struct rq *finish_task_switch(struct task_struct *prev) * @prev: the thread we just switched away from. */ asmlinkage __visible void schedule_tail(struct task_struct *prev) - __releases(rq->lock) + __releases(__rq_lockp(this_rq())) { /* * New tasks start with FORK_PREEMPT_COUNT, see there and @@ -5201,6 +5224,7 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev) static __always_inline struct rq * context_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next, struct rq_flags *rf) + __releases(__rq_lockp(rq)) { prepare_task_switch(rq, prev, next); @@ -5869,6 +5893,7 @@ static void prev_balance(struct rq *rq, struct task_struct *prev, */ static inline struct task_struct * __pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) + __must_hold(__rq_lockp(rq)) { const struct sched_class *class; struct task_struct *p; @@ -5969,6 +5994,7 @@ static void queue_core_balance(struct rq *rq); static struct task_struct * pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) + __must_hold(__rq_lockp(rq)) { struct task_struct *next, *p, *max; const struct cpumask *smt_mask; @@ -6277,6 +6303,7 @@ static bool steal_cookie_task(int cpu, struct sched_domain *sd) } static void sched_core_balance(struct rq *rq) + __must_hold(__rq_lockp(rq)) { struct sched_domain *sd; int cpu = cpu_of(rq); @@ -6422,6 +6449,7 @@ static inline void sched_core_cpu_dying(unsigned int cpu) {} static struct task_struct * pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) + __must_hold(__rq_lockp(rq)) { return __pick_next_task(rq, prev, rf); } @@ -8045,6 +8073,12 @@ static int __balance_push_cpu_stop(void *arg) int cpu; scoped_guard (raw_spinlock_irq, &p->pi_lock) { + /* + * We may change the underlying rq, but the locks held will + * appropriately be "transferred" when switching. + */ + context_unsafe_alias(rq); + cpu = select_fallback_rq(rq->cpu, p); rq_lock(rq, &rf); @@ -8068,6 +8102,7 @@ static DEFINE_PER_CPU(struct cpu_stop_work, push_work); * effective when the hotplug motion is down. */ static void balance_push(struct rq *rq) + __must_hold(__rq_lockp(rq)) { struct task_struct *push_task = rq->curr; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 3eaeceda71b0..c3502c3c7b88 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2860,6 +2860,7 @@ static int preferred_group_nid(struct task_struct *p, int nid) } static void task_numa_placement(struct task_struct *p) + __context_unsafe(/* conditional locking */) { int seq, nid, max_nid = NUMA_NO_NODE; unsigned long max_faults = 0; @@ -4781,7 +4782,8 @@ static inline unsigned long cfs_rq_load_avg(struct cfs_rq *cfs_rq) return cfs_rq->avg.load_avg; } -static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf); +static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) + __must_hold(__rq_lockp(this_rq)); static inline unsigned long task_util(struct task_struct *p) { @@ -6188,6 +6190,7 @@ next: * used to track this state. */ static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun, unsigned long flags) + __must_hold(&cfs_b->lock) { int throttled; @@ -8909,6 +8912,7 @@ static void set_next_task_fair(struct rq *rq, struct task_struct *p, bool first) struct task_struct * pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) + __must_hold(__rq_lockp(rq)) { struct sched_entity *se; struct task_struct *p; @@ -12842,6 +12846,7 @@ static inline void nohz_newidle_balance(struct rq *this_rq) { } * > 0 - success, new (fair) tasks present */ static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) + __must_hold(__rq_lockp(this_rq)) { unsigned long next_balance = jiffies + HZ; int this_cpu = this_rq->cpu; diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index bcd78b19149b..275370854481 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1362,8 +1362,13 @@ static inline u32 sched_rng(void) return prandom_u32_state(this_cpu_ptr(&sched_rnd_state)); } +static __always_inline struct rq *__this_rq(void) +{ + return this_cpu_ptr(&runqueues); +} + #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) -#define this_rq() this_cpu_ptr(&runqueues) +#define this_rq() __this_rq() #define task_rq(p) cpu_rq(task_cpu(p)) #define cpu_curr(cpu) (cpu_rq(cpu)->curr) #define raw_rq() raw_cpu_ptr(&runqueues) @@ -1430,6 +1435,7 @@ static inline raw_spinlock_t *rq_lockp(struct rq *rq) } static inline raw_spinlock_t *__rq_lockp(struct rq *rq) + __returns_ctx_lock(rq_lockp(rq)) /* alias them */ { if (rq->core_enabled) return &rq->core->__lock; @@ -1529,6 +1535,7 @@ static inline raw_spinlock_t *rq_lockp(struct rq *rq) } static inline raw_spinlock_t *__rq_lockp(struct rq *rq) + __returns_ctx_lock(rq_lockp(rq)) /* alias them */ { return &rq->__lock; } @@ -1571,32 +1578,42 @@ static inline bool rt_group_sched_enabled(void) #endif /* !CONFIG_RT_GROUP_SCHED */ static inline void lockdep_assert_rq_held(struct rq *rq) + __assumes_ctx_lock(__rq_lockp(rq)) { lockdep_assert_held(__rq_lockp(rq)); } -extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass); -extern bool raw_spin_rq_trylock(struct rq *rq); -extern void raw_spin_rq_unlock(struct rq *rq); +extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass) + __acquires(__rq_lockp(rq)); + +extern bool raw_spin_rq_trylock(struct rq *rq) + __cond_acquires(true, __rq_lockp(rq)); + +extern void raw_spin_rq_unlock(struct rq *rq) + __releases(__rq_lockp(rq)); static inline void raw_spin_rq_lock(struct rq *rq) + __acquires(__rq_lockp(rq)) { raw_spin_rq_lock_nested(rq, 0); } static inline void raw_spin_rq_lock_irq(struct rq *rq) + __acquires(__rq_lockp(rq)) { local_irq_disable(); raw_spin_rq_lock(rq); } static inline void raw_spin_rq_unlock_irq(struct rq *rq) + __releases(__rq_lockp(rq)) { raw_spin_rq_unlock(rq); local_irq_enable(); } static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) + __acquires(__rq_lockp(rq)) { unsigned long flags; @@ -1607,6 +1624,7 @@ static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) } static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) + __releases(__rq_lockp(rq)) { raw_spin_rq_unlock(rq); local_irq_restore(flags); @@ -1855,18 +1873,16 @@ static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) rq->clock_update_flags |= rf->clock_update_flags; } -extern -struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(rq->lock); +#define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) +extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret; -extern -struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) - __acquires(p->pi_lock) - __acquires(rq->lock); +#define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) +extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) + __acquires(&p->pi_lock) __acquires_ret; static inline void __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) - __releases(rq->lock) + __releases(__rq_lockp(rq)) { rq_unpin_lock(rq, rf); raw_spin_rq_unlock(rq); @@ -1874,8 +1890,7 @@ __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) static inline void task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) - __releases(rq->lock) - __releases(p->pi_lock) + __releases(__rq_lockp(rq), &p->pi_lock) { __task_rq_unlock(rq, p, rf); raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); @@ -1885,6 +1900,8 @@ DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, _T->rq = task_rq_lock(_T->lock, &_T->rf), task_rq_unlock(_T->rq, _T->lock, &_T->rf), struct rq *rq; struct rq_flags rf) +DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock)) +#define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T) DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, _T->rq = __task_rq_lock(_T->lock, &_T->rf), @@ -1892,42 +1909,42 @@ DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, struct rq *rq; struct rq_flags rf) static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) + __acquires(__rq_lockp(rq)) { raw_spin_rq_lock_irqsave(rq, rf->flags); rq_pin_lock(rq, rf); } static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) + __acquires(__rq_lockp(rq)) { raw_spin_rq_lock_irq(rq); rq_pin_lock(rq, rf); } static inline void rq_lock(struct rq *rq, struct rq_flags *rf) - __acquires(rq->lock) + __acquires(__rq_lockp(rq)) { raw_spin_rq_lock(rq); rq_pin_lock(rq, rf); } static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) + __releases(__rq_lockp(rq)) { rq_unpin_lock(rq, rf); raw_spin_rq_unlock_irqrestore(rq, rf->flags); } static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) + __releases(__rq_lockp(rq)) { rq_unpin_lock(rq, rf); raw_spin_rq_unlock_irq(rq); } static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) - __releases(rq->lock) + __releases(__rq_lockp(rq)) { rq_unpin_lock(rq, rf); raw_spin_rq_unlock(rq); @@ -1938,18 +1955,27 @@ DEFINE_LOCK_GUARD_1(rq_lock, struct rq, rq_unlock(_T->lock, &_T->rf), struct rq_flags rf) +DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); +#define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T) + DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, rq_lock_irq(_T->lock, &_T->rf), rq_unlock_irq(_T->lock, &_T->rf), struct rq_flags rf) +DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); +#define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T) + DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, rq_lock_irqsave(_T->lock, &_T->rf), rq_unlock_irqrestore(_T->lock, &_T->rf), struct rq_flags rf) -static inline struct rq *this_rq_lock_irq(struct rq_flags *rf) - __acquires(rq->lock) +DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); +#define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T) + +#define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret)) +static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret { struct rq *rq; @@ -3077,8 +3103,20 @@ static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ + __no_context_analysis \ { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ _lock; return _t; } +#define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2) \ +static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1, \ + lock_##_name##_t *_T2) _lock; \ +static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1) \ + __no_context_analysis _unlock1 { } \ +static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2) \ + __no_context_analysis _unlock2 { } +#define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2) \ + class_##_name##_constructor(_T1, _T2), \ + *__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\ + *__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2) static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) { @@ -3106,7 +3144,8 @@ static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) return rq1->cpu < rq2->cpu; } -extern void double_rq_lock(struct rq *rq1, struct rq *rq2); +extern void double_rq_lock(struct rq *rq1, struct rq *rq2) + __acquires(__rq_lockp(rq1), __rq_lockp(rq2)); #ifdef CONFIG_PREEMPTION @@ -3119,9 +3158,8 @@ extern void double_rq_lock(struct rq *rq1, struct rq *rq2); * also adds more overhead and therefore may reduce throughput. */ static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) - __releases(this_rq->lock) - __acquires(busiest->lock) - __acquires(this_rq->lock) + __must_hold(__rq_lockp(this_rq)) + __acquires(__rq_lockp(busiest)) { raw_spin_rq_unlock(this_rq); double_rq_lock(this_rq, busiest); @@ -3138,12 +3176,16 @@ static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) * regardless of entry order into the function. */ static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) - __releases(this_rq->lock) - __acquires(busiest->lock) - __acquires(this_rq->lock) + __must_hold(__rq_lockp(this_rq)) + __acquires(__rq_lockp(busiest)) { - if (__rq_lockp(this_rq) == __rq_lockp(busiest) || - likely(raw_spin_rq_trylock(busiest))) { + if (__rq_lockp(this_rq) == __rq_lockp(busiest)) { + __acquire(__rq_lockp(busiest)); /* already held */ + double_rq_clock_clear_update(this_rq, busiest); + return 0; + } + + if (likely(raw_spin_rq_trylock(busiest))) { double_rq_clock_clear_update(this_rq, busiest); return 0; } @@ -3166,6 +3208,8 @@ static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) * double_lock_balance - lock the busiest runqueue, this_rq is locked already. */ static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) + __must_hold(__rq_lockp(this_rq)) + __acquires(__rq_lockp(busiest)) { lockdep_assert_irqs_disabled(); @@ -3173,14 +3217,17 @@ static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) } static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) - __releases(busiest->lock) + __releases(__rq_lockp(busiest)) { if (__rq_lockp(this_rq) != __rq_lockp(busiest)) raw_spin_rq_unlock(busiest); + else + __release(__rq_lockp(busiest)); /* fake release */ lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); } static inline void double_lock(spinlock_t *l1, spinlock_t *l2) + __acquires(l1, l2) { if (l1 > l2) swap(l1, l2); @@ -3190,6 +3237,7 @@ static inline void double_lock(spinlock_t *l1, spinlock_t *l2) } static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) + __acquires(l1, l2) { if (l1 > l2) swap(l1, l2); @@ -3199,6 +3247,7 @@ static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) } static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) + __acquires(l1, l2) { if (l1 > l2) swap(l1, l2); @@ -3208,6 +3257,7 @@ static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) } static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) + __releases(l1, l2) { raw_spin_unlock(l1); raw_spin_unlock(l2); @@ -3217,6 +3267,13 @@ DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, double_raw_lock(_T->lock, _T->lock2), double_raw_unlock(_T->lock, _T->lock2)) +DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock, + __acquires(_T1, _T2), + __releases(*(raw_spinlock_t **)_T1), + __releases(*(raw_spinlock_t **)_T2)); +#define class_double_raw_spinlock_constructor(_T1, _T2) \ + WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2) + /* * double_rq_unlock - safely unlock two runqueues * @@ -3224,13 +3281,12 @@ DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, * you need to do so manually after calling. */ static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) - __releases(rq1->lock) - __releases(rq2->lock) + __releases(__rq_lockp(rq1), __rq_lockp(rq2)) { if (__rq_lockp(rq1) != __rq_lockp(rq2)) raw_spin_rq_unlock(rq2); else - __release(rq2->lock); + __release(__rq_lockp(rq2)); /* fake release */ raw_spin_rq_unlock(rq1); } |
