diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/cpumask.h | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/ptrace.h | 2 | ||||
| -rw-r--r-- | include/asm-generic/bitops/instrumented-atomic.h | 12 | ||||
| -rw-r--r-- | include/asm-generic/bitops/instrumented-non-atomic.h | 16 | ||||
| -rw-r--r-- | include/linux/atomic/atomic-arch-fallback.h | 38 | ||||
| -rw-r--r-- | include/linux/cpumask.h | 18 | ||||
| -rw-r--r-- | include/linux/jump_label.h | 13 | ||||
| -rw-r--r-- | include/linux/local_lock_internal.h | 6 | ||||
| -rw-r--r-- | init/Kconfig | 1 | ||||
| -rw-r--r-- | kernel/locking/lockdep.c | 43 | ||||
| -rw-r--r-- | kernel/locking/lockdep_internals.h | 6 | ||||
| -rw-r--r-- | kernel/locking/lockdep_proc.c | 51 | ||||
| -rw-r--r-- | kernel/locking/percpu-rwsem.c | 5 | ||||
| -rw-r--r-- | kernel/locking/rwsem.c | 2 | ||||
| -rwxr-xr-x | scripts/atomic/fallbacks/read_acquire | 11 | ||||
| -rwxr-xr-x | scripts/atomic/fallbacks/set_release | 7 |
17 files changed, 168 insertions, 74 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 4386b12f86e8..37adcd621a02 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3205,6 +3205,7 @@ ATOMIC INFRASTRUCTURE M: Will Deacon <will@kernel.org> M: Peter Zijlstra <peterz@infradead.org> R: Boqun Feng <boqun.feng@gmail.com> +R: Mark Rutland <mark.rutland@arm.com> L: linux-kernel@vger.kernel.org S: Maintained F: arch/*/include/asm/atomic*.h diff --git a/arch/x86/include/asm/cpumask.h b/arch/x86/include/asm/cpumask.h index 3afa990d756b..c5aed9e9226c 100644 --- a/arch/x86/include/asm/cpumask.h +++ b/arch/x86/include/asm/cpumask.h @@ -20,11 +20,21 @@ static __always_inline bool arch_cpu_online(int cpu) { return arch_test_bit(cpu, cpumask_bits(cpu_online_mask)); } + +static __always_inline void arch_cpumask_clear_cpu(int cpu, struct cpumask *dstp) +{ + arch_clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); +} #else static __always_inline bool arch_cpu_online(int cpu) { return cpu == 0; } + +static __always_inline void arch_cpumask_clear_cpu(int cpu, struct cpumask *dstp) +{ + return; +} #endif #define arch_cpu_is_offline(cpu) unlikely(!arch_cpu_online(cpu)) diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 703663175a5a..4357e0f2cd5f 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -137,7 +137,7 @@ static __always_inline int user_mode(struct pt_regs *regs) #endif } -static inline int v8086_mode(struct pt_regs *regs) +static __always_inline int v8086_mode(struct pt_regs *regs) { #ifdef CONFIG_X86_32 return (regs->flags & X86_VM_MASK); diff --git a/include/asm-generic/bitops/instrumented-atomic.h b/include/asm-generic/bitops/instrumented-atomic.h index c90192b1c755..4225a8ca9c1a 100644 --- a/include/asm-generic/bitops/instrumented-atomic.h +++ b/include/asm-generic/bitops/instrumented-atomic.h @@ -23,7 +23,7 @@ * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ -static inline void set_bit(long nr, volatile unsigned long *addr) +static __always_inline void set_bit(long nr, volatile unsigned long *addr) { instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long)); arch_set_bit(nr, addr); @@ -36,7 +36,7 @@ static inline void set_bit(long nr, volatile unsigned long *addr) * * This is a relaxed atomic operation (no implied memory barriers). */ -static inline void clear_bit(long nr, volatile unsigned long *addr) +static __always_inline void clear_bit(long nr, volatile unsigned long *addr) { instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long)); arch_clear_bit(nr, addr); @@ -52,7 +52,7 @@ static inline void clear_bit(long nr, volatile unsigned long *addr) * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ -static inline void change_bit(long nr, volatile unsigned long *addr) +static __always_inline void change_bit(long nr, volatile unsigned long *addr) { instrument_atomic_write(addr + BIT_WORD(nr), sizeof(long)); arch_change_bit(nr, addr); @@ -65,7 +65,7 @@ static inline void change_bit(long nr, volatile unsigned long *addr) * * This is an atomic fully-ordered operation (implied full memory barrier). */ -static inline bool test_and_set_bit(long nr, volatile unsigned long *addr) +static __always_inline bool test_and_set_bit(long nr, volatile unsigned long *addr) { kcsan_mb(); instrument_atomic_read_write(addr + BIT_WORD(nr), sizeof(long)); @@ -79,7 +79,7 @@ static inline bool test_and_set_bit(long nr, volatile unsigned long *addr) * * This is an atomic fully-ordered operation (implied full memory barrier). */ -static inline bool test_and_clear_bit(long nr, volatile unsigned long *addr) +static __always_inline bool test_and_clear_bit(long nr, volatile unsigned long *addr) { kcsan_mb(); instrument_atomic_read_write(addr + BIT_WORD(nr), sizeof(long)); @@ -93,7 +93,7 @@ static inline bool test_and_clear_bit(long nr, volatile unsigned long *addr) * * This is an atomic fully-ordered operation (implied full memory barrier). */ -static inline bool test_and_change_bit(long nr, volatile unsigned long *addr) +static __always_inline bool test_and_change_bit(long nr, volatile unsigned long *addr) { kcsan_mb(); instrument_atomic_read_write(addr + BIT_WORD(nr), sizeof(long)); diff --git a/include/asm-generic/bitops/instrumented-non-atomic.h b/include/asm-generic/bitops/instrumented-non-atomic.h index 37363d570b9b..7ab1ecc37782 100644 --- a/include/asm-generic/bitops/instrumented-non-atomic.h +++ b/include/asm-generic/bitops/instrumented-non-atomic.h @@ -22,7 +22,7 @@ * region of memory concurrently, the effect may be that only one operation * succeeds. */ -static inline void __set_bit(long nr, volatile unsigned long *addr) +static __always_inline void __set_bit(long nr, volatile unsigned long *addr) { instrument_write(addr + BIT_WORD(nr), sizeof(long)); arch___set_bit(nr, addr); @@ -37,7 +37,7 @@ static inline void __set_bit(long nr, volatile unsigned long *addr) * region of memory concurrently, the effect may be that only one operation * succeeds. */ -static inline void __clear_bit(long nr, volatile unsigned long *addr) +static __always_inline void __clear_bit(long nr, volatile unsigned long *addr) { instrument_write(addr + BIT_WORD(nr), sizeof(long)); arch___clear_bit(nr, addr); @@ -52,13 +52,13 @@ static inline void __clear_bit(long nr, volatile unsigned long *addr) * region of memory concurrently, the effect may be that only one operation * succeeds. */ -static inline void __change_bit(long nr, volatile unsigned long *addr) +static __always_inline void __change_bit(long nr, volatile unsigned long *addr) { instrument_write(addr + BIT_WORD(nr), sizeof(long)); arch___change_bit(nr, addr); } -static inline void __instrument_read_write_bitop(long nr, volatile unsigned long *addr) +static __always_inline void __instrument_read_write_bitop(long nr, volatile unsigned long *addr) { if (IS_ENABLED(CONFIG_KCSAN_ASSUME_PLAIN_WRITES_ATOMIC)) { /* @@ -90,7 +90,7 @@ static inline void __instrument_read_write_bitop(long nr, volatile unsigned long * This operation is non-atomic. If two instances of this operation race, one * can appear to succeed but actually fail. */ -static inline bool __test_and_set_bit(long nr, volatile unsigned long *addr) +static __always_inline bool __test_and_set_bit(long nr, volatile unsigned long *addr) { __instrument_read_write_bitop(nr, addr); return arch___test_and_set_bit(nr, addr); @@ -104,7 +104,7 @@ static inline bool __test_and_set_bit(long nr, volatile unsigned long *addr) * This operation is non-atomic. If two instances of this operation race, one * can appear to succeed but actually fail. */ -static inline bool __test_and_clear_bit(long nr, volatile unsigned long *addr) +static __always_inline bool __test_and_clear_bit(long nr, volatile unsigned long *addr) { __instrument_read_write_bitop(nr, addr); return arch___test_and_clear_bit(nr, addr); @@ -118,7 +118,7 @@ static inline bool __test_and_clear_bit(long nr, volatile unsigned long *addr) * This operation is non-atomic. If two instances of this operation race, one * can appear to succeed but actually fail. */ -static inline bool __test_and_change_bit(long nr, volatile unsigned long *addr) +static __always_inline bool __test_and_change_bit(long nr, volatile unsigned long *addr) { __instrument_read_write_bitop(nr, addr); return arch___test_and_change_bit(nr, addr); @@ -129,7 +129,7 @@ static inline bool __test_and_change_bit(long nr, volatile unsigned long *addr) * @nr: bit number to test * @addr: Address to start counting from */ -static inline bool test_bit(long nr, const volatile unsigned long *addr) +static __always_inline bool test_bit(long nr, const volatile unsigned long *addr) { instrument_atomic_read(addr + BIT_WORD(nr), sizeof(long)); return arch_test_bit(nr, addr); diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h index a3dba31df01e..6db58d180866 100644 --- a/include/linux/atomic/atomic-arch-fallback.h +++ b/include/linux/atomic/atomic-arch-fallback.h @@ -151,7 +151,16 @@ static __always_inline int arch_atomic_read_acquire(const atomic_t *v) { - return smp_load_acquire(&(v)->counter); + int ret; + + if (__native_word(atomic_t)) { + ret = smp_load_acquire(&(v)->counter); + } else { + ret = arch_atomic_read(v); + __atomic_acquire_fence(); + } + + return ret; } #define arch_atomic_read_acquire arch_atomic_read_acquire #endif @@ -160,7 +169,12 @@ arch_atomic_read_acquire(const atomic_t *v) static __always_inline void arch_atomic_set_release(atomic_t *v, int i) { - smp_store_release(&(v)->counter, i); + if (__native_word(atomic_t)) { + smp_store_release(&(v)->counter, i); + } else { + __atomic_release_fence(); + arch_atomic_set(v, i); + } } #define arch_atomic_set_release arch_atomic_set_release #endif @@ -1258,7 +1272,16 @@ arch_atomic_dec_if_positive(atomic_t *v) static __always_inline s64 arch_atomic64_read_acquire(const atomic64_t *v) { - return smp_load_acquire(&(v)->counter); + s64 ret; + + if (__native_word(atomic64_t)) { + ret = smp_load_acquire(&(v)->counter); + } else { + ret = arch_atomic64_read(v); + __atomic_acquire_fence(); + } + + return ret; } #define arch_atomic64_read_acquire arch_atomic64_read_acquire #endif @@ -1267,7 +1290,12 @@ arch_atomic64_read_acquire(const atomic64_t *v) static __always_inline void arch_atomic64_set_release(atomic64_t *v, s64 i) { - smp_store_release(&(v)->counter, i); + if (__native_word(atomic64_t)) { + smp_store_release(&(v)->counter, i); + } else { + __atomic_release_fence(); + arch_atomic64_set(v, i); + } } #define arch_atomic64_set_release arch_atomic64_set_release #endif @@ -2358,4 +2386,4 @@ arch_atomic64_dec_if_positive(atomic64_t *v) #endif #endif /* _LINUX_ATOMIC_FALLBACK_H */ -// cca554917d7ea73d5e3e7397dd70c484cad9b2c4 +// 8e2cc06bc0d2c0967d2f8424762bd48555ee40ae diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 64dae70d31f5..fe29ac7cc469 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -102,7 +102,7 @@ extern atomic_t __num_online_cpus; extern cpumask_t cpus_booted_once_mask; -static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) +static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) { #ifdef CONFIG_DEBUG_PER_CPU_MAPS WARN_ON_ONCE(cpu >= bits); @@ -110,7 +110,7 @@ static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) } /* verify cpu argument to cpumask_* operators */ -static inline unsigned int cpumask_check(unsigned int cpu) +static __always_inline unsigned int cpumask_check(unsigned int cpu) { cpu_max_bits_warn(cpu, nr_cpumask_bits); return cpu; @@ -341,12 +341,12 @@ extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool * @cpu: cpu number (< nr_cpu_ids) * @dstp: the cpumask pointer */ -static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) +static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) { set_bit(cpumask_check(cpu), cpumask_bits(dstp)); } -static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) +static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) { __set_bit(cpumask_check(cpu), cpumask_bits(dstp)); } @@ -357,12 +357,12 @@ static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) * @cpu: cpu number (< nr_cpu_ids) * @dstp: the cpumask pointer */ -static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) +static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) { clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); } -static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) +static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) { __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); } @@ -374,7 +374,7 @@ static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) * * Returns 1 if @cpu is set in @cpumask, else returns 0 */ -static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) +static __always_inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) { return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); } @@ -388,7 +388,7 @@ static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) * * test_and_set_bit wrapper for cpumasks. */ -static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) +static __always_inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) { return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); } @@ -402,7 +402,7 @@ static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) * * test_and_clear_bit wrapper for cpumasks. */ -static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) +static __always_inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) { return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); } diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 48b9b2a82767..107751cc047b 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -82,10 +82,9 @@ extern bool static_key_initialized; "%s(): static key '%pS' used before call to jump_label_init()", \ __func__, (key)) -#ifdef CONFIG_JUMP_LABEL - struct static_key { atomic_t enabled; +#ifdef CONFIG_JUMP_LABEL /* * Note: * To make anonymous unions work with old compilers, the static @@ -104,13 +103,9 @@ struct static_key { struct jump_entry *entries; struct static_key_mod *next; }; +#endif /* CONFIG_JUMP_LABEL */ }; -#else -struct static_key { - atomic_t enabled; -}; -#endif /* CONFIG_JUMP_LABEL */ #endif /* __ASSEMBLY__ */ #ifdef CONFIG_JUMP_LABEL @@ -251,10 +246,10 @@ extern void static_key_disable_cpuslocked(struct static_key *key); */ #define STATIC_KEY_INIT_TRUE \ { .enabled = { 1 }, \ - { .entries = (void *)JUMP_TYPE_TRUE } } + { .type = JUMP_TYPE_TRUE } } #define STATIC_KEY_INIT_FALSE \ { .enabled = { 0 }, \ - { .entries = (void *)JUMP_TYPE_FALSE } } + { .type = JUMP_TYPE_FALSE } } #else /* !CONFIG_JUMP_LABEL */ diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h index 975e33b793a7..6d635e8306d6 100644 --- a/include/linux/local_lock_internal.h +++ b/include/linux/local_lock_internal.h @@ -44,9 +44,9 @@ static inline void local_lock_debug_init(local_lock_t *l) } #else /* CONFIG_DEBUG_LOCK_ALLOC */ # define LOCAL_LOCK_DEBUG_INIT(lockname) -static inline void local_lock_acquire(local_lock_t *l) { } -static inline void local_lock_release(local_lock_t *l) { } -static inline void local_lock_debug_init(local_lock_t *l) { } +# define local_lock_acquire(__ll) do { typecheck(local_lock_t *, __ll); } while (0) +# define local_lock_release(__ll) do { typecheck(local_lock_t *, __ll); } while (0) +# define local_lock_debug_init(__ll) do { typecheck(local_lock_t *, __ll); } while (0) #endif /* !CONFIG_DEBUG_LOCK_ALLOC */ #define INIT_LOCAL_LOCK(lockname) { LOCAL_LOCK_DEBUG_INIT(lockname) } diff --git a/init/Kconfig b/init/Kconfig index e9119bf54b1f..beb5b866c318 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2054,6 +2054,7 @@ source "arch/Kconfig" config RT_MUTEXES bool + default y if PREEMPT_RT config BASE_SMALL int diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index f8a0212189ca..c06cab6546ed 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -183,11 +183,9 @@ static DECLARE_BITMAP(list_entries_in_use, MAX_LOCKDEP_ENTRIES); static struct hlist_head lock_keys_hash[KEYHASH_SIZE]; unsigned long nr_lock_classes; unsigned long nr_zapped_classes; -#ifndef CONFIG_DEBUG_LOCKDEP -static -#endif +unsigned long max_lock_class_idx; struct lock_class lock_classes[MAX_LOCKDEP_KEYS]; -static DECLARE_BITMAP(lock_classes_in_use, MAX_LOCKDEP_KEYS); +DECLARE_BITMAP(lock_classes_in_use, MAX_LOCKDEP_KEYS); static inline struct lock_class *hlock_class(struct held_lock *hlock) { @@ -338,7 +336,7 @@ static inline void lock_release_holdtime(struct held_lock *hlock) * elements. These elements are linked together by the lock_entry member in * struct lock_class. */ -LIST_HEAD(all_lock_classes); +static LIST_HEAD(all_lock_classes); static LIST_HEAD(free_lock_classes); /** @@ -1252,6 +1250,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) struct lockdep_subclass_key *key; struct hlist_head *hash_head; struct lock_class *class; + int idx; DEBUG_LOCKS_WARN_ON(!irqs_disabled()); @@ -1317,6 +1316,9 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) * of classes. */ list_move_tail(&class->lock_entry, &all_lock_classes); + idx = class - lock_classes; + if (idx > max_lock_class_idx) + max_lock_class_idx = idx; if (verbose(class)) { graph_unlock(); @@ -6000,6 +6002,8 @@ static void zap_class(struct pending_free *pf, struct lock_class *class) WRITE_ONCE(class->name, NULL); nr_lock_classes--; __clear_bit(class - lock_classes, lock_classes_in_use); + if (class - lock_classes == max_lock_class_idx) + max_lock_class_idx--; } else { WARN_ONCE(true, "%s() failed for class %s\n", __func__, class->name); @@ -6011,13 +6015,10 @@ static void zap_class(struct pending_free *pf, struct lock_class *class) static void reinit_class(struct lock_class *class) { - void *const p = class; - const unsigned int offset = offsetof(struct lock_class, key); - WARN_ON_ONCE(!class->lock_entry.next); WARN_ON_ONCE(!list_empty(&class->locks_after)); WARN_ON_ONCE(!list_empty(&class->locks_before)); - memset(p + offset, 0, sizeof(*class) - offset); + memset_startat(class, 0, key); WARN_ON_ONCE(!class->lock_entry.next); WARN_ON_ONCE(!list_empty(&class->locks_after)); WARN_ON_ONCE(!list_empty(&class->locks_before)); @@ -6290,7 +6291,13 @@ void lockdep_reset_lock(struct lockdep_map *lock) lockdep_reset_lock_reg(lock); } -/* Unregister a dynamically allocated key. */ +/* + * Unregister a dynamically allocated key. + * + * Unlike lockdep_register_key(), a search is always done to find a matching + * key irrespective of debug_locks to avoid potential invalid access to freed + * memory in lock_class entry. + */ void lockdep_unregister_key(struct lock_class_key *key) { struct hlist_head *hash_head = keyhashentry(key); @@ -6305,10 +6312,8 @@ void lockdep_unregister_key(struct lock_class_key *key) return; raw_local_irq_save(flags); - if (!graph_lock()) - goto out_irq; + lockdep_lock(); - pf = get_pending_free(); hlist_for_each_entry_rcu(k, hash_head, hash_entry) { if (k == key) { hlist_del_rcu(&k->hash_entry); @@ -6316,11 +6321,13 @@ void lockdep_unregister_key(struct lock_class_key *key) break; } } - WARN_ON_ONCE(!found); - __lockdep_free_key_range(pf, key, 1); - call_rcu_zapped(pf); - graph_unlock(); -out_irq: + WARN_ON_ONCE(!found && debug_locks); + if (found) { + pf = get_pending_free(); + __lockdep_free_key_range(pf, key, 1); + call_rcu_zapped(pf); + } + lockdep_unlock(); raw_local_irq_restore(flags); /* Wait until is_dynamic_key() has finished accessing k->hash_entry. */ diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index ecb8662e7a4e..bbe9000260d0 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -121,7 +121,6 @@ static const unsigned long LOCKF_USED_IN_IRQ_READ = #define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5) -extern struct list_head all_lock_classes; extern struct lock_chain lock_chains[]; #define LOCK_USAGE_CHARS (2*XXX_LOCK_USAGE_STATES + 1) @@ -151,6 +150,10 @@ extern unsigned int nr_large_chain_blocks; extern unsigned int max_lockdep_depth; extern unsigned int max_bfs_queue_depth; +extern unsigned long max_lock_class_idx; + +extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS]; +extern unsigned long lock_classes_in_use[]; #ifdef CONFIG_PROVE_LOCKING extern unsigned long lockdep_count_forward_deps(struct lock_class *); @@ -205,7 +208,6 @@ struct lockdep_stats { }; DECLARE_PER_CPU(struct lockdep_stats, lockdep_stats); -extern struct lock_class lock_classes[MAX_LOCKDEP_KEYS]; #define __debug_atomic_inc(ptr) \ this_cpu_inc(lockdep_stats.ptr); diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index b8d9a050c337..15fdc7fa5c68 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -24,14 +24,33 @@ #include "lockdep_internals.h" +/* + * Since iteration of lock_classes is done without holding the lockdep lock, + * it is not safe to iterate all_lock_classes list directly as the iteration + * may branch off to free_lock_classes or the zapped list. Iteration is done + * directly on the lock_classes array by checking the lock_classes_in_use + * bitmap and max_lock_class_idx. + */ +#define iterate_lock_classes(idx, class) \ + for (idx = 0, class = lock_classes; idx <= max_lock_class_idx; \ + idx++, class++) + static void *l_next(struct seq_file *m, void *v, loff_t *pos) { - return seq_list_next(v, &all_lock_classes, pos); + struct lock_class *class = v; + + ++class; + *pos = class - lock_classes; + return (*pos > max_lock_class_idx) ? NULL : class; } static void *l_start(struct seq_file *m, loff_t *pos) { - return seq_list_start_head(&all_lock_classes, *pos); + unsigned long idx = *pos; + + if (idx > max_lock_class_idx) + return NULL; + return lock_classes + idx; } static void l_stop(struct seq_file *m, void *v) @@ -57,14 +76,16 @@ static void print_name(struct seq_file *m, struct lock_class *class) static int l_show(struct seq_file *m, void *v) { - struct lock_class *class = list_entry(v, struct lock_class, lock_entry); + struct lock_class *class = v; struct lock_list *entry; char usage[LOCK_USAGE_CHARS]; + int idx = class - lock_classes; - if (v == &all_lock_classes) { + if (v == lock_classes) seq_printf(m, "all lock classes:\n"); + + if (!test_bit(idx, lock_classes_in_use)) return 0; - } seq_printf(m, "%p", class->key); #ifdef CONFIG_DEBUG_LOCKDEP @@ -220,8 +241,11 @@ static int lockdep_stats_show(struct seq_file *m, void *v) #ifdef CONFIG_PROVE_LOCKING struct lock_class *class; + unsigned long idx; - list_for_each_entry(class, &all_lock_classes, lock_entry) { + iterate_lock_classes(idx, class) { + if (!test_bit(idx, lock_classes_in_use)) + continue; if (class->usage_mask == 0) nr_unused++; @@ -254,6 +278,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v) sum_forward_deps += lockdep_count_forward_deps(class); } + #ifdef CONFIG_DEBUG_LOCKDEP DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused); #endif @@ -345,6 +370,8 @@ static int lockdep_stats_show(struct seq_file *m, void *v) seq_printf(m, " max bfs queue depth: %11u\n", max_bfs_queue_depth); #endif + seq_printf(m, " max lock class index: %11lu\n", + max_lock_class_idx); lockdep_stats_debug_show(m); seq_printf(m, " debug_locks: %11u\n", debug_locks); @@ -622,12 +649,16 @@ static int lock_stat_open(struct inode *inode, struct file *file) if (!res) { struct lock_stat_data *iter = data->stats; struct seq_file *m = file->private_data; + unsigned long idx; - list_for_each_entry(class, &all_lock_classes, lock_entry) { + iterate_lock_classes(idx, class) { + if (!test_bit(idx, lock_classes_in_use)) + continue; iter->class = class; iter->stats = lock_stats(class); iter++; } + data->iter_end = iter; sort(data->stats, data->iter_end - data->stats, @@ -645,6 +676,7 @@ static ssize_t lock_stat_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { struct lock_class *class; + unsigned long idx; char c; if (count) { @@ -654,8 +686,11 @@ static ssize_t lock_stat_write(struct file *file, const char __user *buf, if (c != '0') return count; - list_for_each_entry(class, &all_lock_classes, lock_entry) + iterate_lock_classes(idx, class) { + if (!test_bit(idx, lock_classes_in_use)) + continue; clear_lock_stats(class); + } } return count; } diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c index 70a32a576f3f..c9fdae94e098 100644 --- a/kernel/locking/percpu-rwsem.c +++ b/kernel/locking/percpu-rwsem.c @@ -7,6 +7,7 @@ #include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/sched/task.h> +#include <linux/sched/debug.h> #include <linux/errno.h> int __percpu_init_rwsem(struct percpu_rw_semaphore *sem, @@ -162,7 +163,7 @@ static void percpu_rwsem_wait(struct percpu_rw_semaphore *sem, bool reader) __set_current_state(TASK_RUNNING); } -bool __percpu_down_read(struct percpu_rw_semaphore *sem, bool try) +bool __sched __percpu_down_read(struct percpu_rw_semaphore *sem, bool try) { if (__percpu_down_read_trylock(sem)) return true; @@ -211,7 +212,7 @@ static bool readers_active_check(struct percpu_rw_semaphore *sem) return true; } -void percpu_down_write(struct percpu_rw_semaphore *sem) +void __sched percpu_down_write(struct percpu_rw_semaphore *sem) { might_sleep(); rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_); diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index 69aba4abe104..acde5d6f1254 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -1048,7 +1048,7 @@ out_nolock: /* * Wait until we successfully acquire the write lock */ -static struct rw_semaphore * +static struct rw_semaphore __sched * rwsem_down_write_slowpath(struct rw_semaphore *sem, int state) { long count; diff --git a/scripts/atomic/fallbacks/read_acquire b/scripts/atomic/fallbacks/read_acquire index 803ba7561076..a0ea1d26e6b2 100755 --- a/scripts/atomic/fallbacks/read_acquire +++ b/scripts/atomic/fallbacks/read_acquire @@ -2,6 +2,15 @@ cat <<EOF static __always_inline ${ret} arch_${atomic}_read_acquire(const ${atomic}_t *v) { - return smp_load_acquire(&(v)->counter); + ${int} ret; + + if (__native_word(${atomic}_t)) { + ret = smp_load_acquire(&(v)->counter); + } else { + ret = arch_${atomic}_read(v); + __atomic_acquire_fence(); + } + + return ret; } EOF diff --git a/scripts/atomic/fallbacks/set_release b/scripts/atomic/fallbacks/set_release index 86ede759f24e..05cdb7f42477 100755 --- a/scripts/atomic/fallbacks/set_release +++ b/scripts/atomic/fallbacks/set_release @@ -2,6 +2,11 @@ cat <<EOF static __always_inline void arch_${atomic}_set_release(${atomic}_t *v, ${int} i) { - smp_store_release(&(v)->counter, i); + if (__native_word(${atomic}_t)) { + smp_store_release(&(v)->counter, i); + } else { + __atomic_release_fence(); + arch_${atomic}_set(v, i); + } } EOF |