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author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-14 16:30:30 +0900 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-14 16:30:30 +0900 |
commit | 5e30025a319910695f5010dc0fb53a23299da14d (patch) | |
tree | 4292bcf78de221c7de1774ccf5ad0ac5a9315c26 /include | |
parent | 7971e23a66c94f1b9bd2d64a3e86dfbfa8c60121 (diff) | |
parent | 90d3839b90fe379557dae4a44735a6af78f42885 (diff) | |
download | linux-stable-5e30025a319910695f5010dc0fb53a23299da14d.tar.gz linux-stable-5e30025a319910695f5010dc0fb53a23299da14d.tar.bz2 linux-stable-5e30025a319910695f5010dc0fb53a23299da14d.zip |
Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking changes from Ingo Molnar:
"The biggest changes:
- add lockdep support for seqcount/seqlocks structures, this
unearthed both bugs and required extra annotation.
- move the various kernel locking primitives to the new
kernel/locking/ directory"
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
block: Use u64_stats_init() to initialize seqcounts
locking/lockdep: Mark __lockdep_count_forward_deps() as static
lockdep/proc: Fix lock-time avg computation
locking/doc: Update references to kernel/mutex.c
ipv6: Fix possible ipv6 seqlock deadlock
cpuset: Fix potential deadlock w/ set_mems_allowed
seqcount: Add lockdep functionality to seqcount/seqlock structures
net: Explicitly initialize u64_stats_sync structures for lockdep
locking: Move the percpu-rwsem code to kernel/locking/
locking: Move the lglocks code to kernel/locking/
locking: Move the rwsem code to kernel/locking/
locking: Move the rtmutex code to kernel/locking/
locking: Move the semaphore core to kernel/locking/
locking: Move the spinlock code to kernel/locking/
locking: Move the lockdep code to kernel/locking/
locking: Move the mutex code to kernel/locking/
hung_task debugging: Add tracepoint to report the hang
x86/locking/kconfig: Update paravirt spinlock Kconfig description
lockstat: Report avg wait and hold times
lockdep, x86/alternatives: Drop ancient lockdep fixup message
...
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/cpuset.h | 4 | ||||
-rw-r--r-- | include/linux/init_task.h | 8 | ||||
-rw-r--r-- | include/linux/lockdep.h | 8 | ||||
-rw-r--r-- | include/linux/mutex.h | 2 | ||||
-rw-r--r-- | include/linux/sched/sysctl.h | 2 | ||||
-rw-r--r-- | include/linux/seqlock.h | 79 | ||||
-rw-r--r-- | include/linux/u64_stats_sync.h | 7 | ||||
-rw-r--r-- | include/trace/events/sched.h | 19 |
8 files changed, 114 insertions, 15 deletions
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index cc1b01cf2035..3fe661fe96d1 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -110,10 +110,14 @@ static inline bool put_mems_allowed(unsigned int seq) static inline void set_mems_allowed(nodemask_t nodemask) { + unsigned long flags; + task_lock(current); + local_irq_save(flags); write_seqcount_begin(¤t->mems_allowed_seq); current->mems_allowed = nodemask; write_seqcount_end(¤t->mems_allowed_seq); + local_irq_restore(flags); task_unlock(current); } diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 5cd0f0949927..b0ed422e4e4a 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -32,10 +32,10 @@ extern struct fs_struct init_fs; #endif #ifdef CONFIG_CPUSETS -#define INIT_CPUSET_SEQ \ - .mems_allowed_seq = SEQCNT_ZERO, +#define INIT_CPUSET_SEQ(tsk) \ + .mems_allowed_seq = SEQCNT_ZERO(tsk.mems_allowed_seq), #else -#define INIT_CPUSET_SEQ +#define INIT_CPUSET_SEQ(tsk) #endif #define INIT_SIGNALS(sig) { \ @@ -220,7 +220,7 @@ extern struct task_group root_task_group; INIT_FTRACE_GRAPH \ INIT_TRACE_RECURSION \ INIT_TASK_RCU_PREEMPT(tsk) \ - INIT_CPUSET_SEQ \ + INIT_CPUSET_SEQ(tsk) \ INIT_VTIME(tsk) \ } diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index cfc2f119779a..92b1bfc5da60 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -497,6 +497,10 @@ static inline void print_irqtrace_events(struct task_struct *curr) #define rwlock_acquire_read(l, s, t, i) lock_acquire_shared_recursive(l, s, t, NULL, i) #define rwlock_release(l, n, i) lock_release(l, n, i) +#define seqcount_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) +#define seqcount_acquire_read(l, s, t, i) lock_acquire_shared_recursive(l, s, t, NULL, i) +#define seqcount_release(l, n, i) lock_release(l, n, i) + #define mutex_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) #define mutex_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i) #define mutex_release(l, n, i) lock_release(l, n, i) @@ -504,11 +508,11 @@ static inline void print_irqtrace_events(struct task_struct *curr) #define rwsem_acquire(l, s, t, i) lock_acquire_exclusive(l, s, t, NULL, i) #define rwsem_acquire_nest(l, s, t, n, i) lock_acquire_exclusive(l, s, t, n, i) #define rwsem_acquire_read(l, s, t, i) lock_acquire_shared(l, s, t, NULL, i) -# define rwsem_release(l, n, i) lock_release(l, n, i) +#define rwsem_release(l, n, i) lock_release(l, n, i) #define lock_map_acquire(l) lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_) #define lock_map_acquire_read(l) lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_) -# define lock_map_release(l) lock_release(l, 1, _THIS_IP_) +#define lock_map_release(l) lock_release(l, 1, _THIS_IP_) #ifdef CONFIG_PROVE_LOCKING # define might_lock(lock) \ diff --git a/include/linux/mutex.h b/include/linux/mutex.h index bab49da8a0f0..d3181936c138 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -131,7 +131,7 @@ static inline int mutex_is_locked(struct mutex *lock) } /* - * See kernel/mutex.c for detailed documentation of these APIs. + * See kernel/locking/mutex.c for detailed documentation of these APIs. * Also see Documentation/mutex-design.txt. */ #ifdef CONFIG_DEBUG_LOCK_ALLOC diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index 10d16c4fbe89..41467f8ff8ec 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -2,8 +2,8 @@ #define _SCHED_SYSCTL_H #ifdef CONFIG_DETECT_HUNG_TASK +extern int sysctl_hung_task_check_count; extern unsigned int sysctl_hung_task_panic; -extern unsigned long sysctl_hung_task_check_count; extern unsigned long sysctl_hung_task_timeout_secs; extern unsigned long sysctl_hung_task_warnings; extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index 21a209336e79..1e8a8b6e837d 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -34,6 +34,7 @@ #include <linux/spinlock.h> #include <linux/preempt.h> +#include <linux/lockdep.h> #include <asm/processor.h> /* @@ -44,10 +45,50 @@ */ typedef struct seqcount { unsigned sequence; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif } seqcount_t; -#define SEQCNT_ZERO { 0 } -#define seqcount_init(x) do { *(x) = (seqcount_t) SEQCNT_ZERO; } while (0) +static inline void __seqcount_init(seqcount_t *s, const char *name, + struct lock_class_key *key) +{ + /* + * Make sure we are not reinitializing a held lock: + */ + lockdep_init_map(&s->dep_map, name, key, 0); + s->sequence = 0; +} + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define SEQCOUNT_DEP_MAP_INIT(lockname) \ + .dep_map = { .name = #lockname } \ + +# define seqcount_init(s) \ + do { \ + static struct lock_class_key __key; \ + __seqcount_init((s), #s, &__key); \ + } while (0) + +static inline void seqcount_lockdep_reader_access(const seqcount_t *s) +{ + seqcount_t *l = (seqcount_t *)s; + unsigned long flags; + + local_irq_save(flags); + seqcount_acquire_read(&l->dep_map, 0, 0, _RET_IP_); + seqcount_release(&l->dep_map, 1, _RET_IP_); + local_irq_restore(flags); +} + +#else +# define SEQCOUNT_DEP_MAP_INIT(lockname) +# define seqcount_init(s) __seqcount_init(s, NULL, NULL) +# define seqcount_lockdep_reader_access(x) +#endif + +#define SEQCNT_ZERO(lockname) { .sequence = 0, SEQCOUNT_DEP_MAP_INIT(lockname)} + /** * __read_seqcount_begin - begin a seq-read critical section (without barrier) @@ -76,6 +117,22 @@ repeat: } /** + * read_seqcount_begin_no_lockdep - start seq-read critical section w/o lockdep + * @s: pointer to seqcount_t + * Returns: count to be passed to read_seqcount_retry + * + * read_seqcount_begin_no_lockdep opens a read critical section of the given + * seqcount, but without any lockdep checking. Validity of the critical + * section is tested by checking read_seqcount_retry function. + */ +static inline unsigned read_seqcount_begin_no_lockdep(const seqcount_t *s) +{ + unsigned ret = __read_seqcount_begin(s); + smp_rmb(); + return ret; +} + +/** * read_seqcount_begin - begin a seq-read critical section * @s: pointer to seqcount_t * Returns: count to be passed to read_seqcount_retry @@ -86,9 +143,8 @@ repeat: */ static inline unsigned read_seqcount_begin(const seqcount_t *s) { - unsigned ret = __read_seqcount_begin(s); - smp_rmb(); - return ret; + seqcount_lockdep_reader_access(s); + return read_seqcount_begin_no_lockdep(s); } /** @@ -108,6 +164,8 @@ static inline unsigned read_seqcount_begin(const seqcount_t *s) static inline unsigned raw_seqcount_begin(const seqcount_t *s) { unsigned ret = ACCESS_ONCE(s->sequence); + + seqcount_lockdep_reader_access(s); smp_rmb(); return ret & ~1; } @@ -152,14 +210,21 @@ static inline int read_seqcount_retry(const seqcount_t *s, unsigned start) * Sequence counter only version assumes that callers are using their * own mutexing. */ -static inline void write_seqcount_begin(seqcount_t *s) +static inline void write_seqcount_begin_nested(seqcount_t *s, int subclass) { s->sequence++; smp_wmb(); + seqcount_acquire(&s->dep_map, subclass, 0, _RET_IP_); +} + +static inline void write_seqcount_begin(seqcount_t *s) +{ + write_seqcount_begin_nested(s, 0); } static inline void write_seqcount_end(seqcount_t *s) { + seqcount_release(&s->dep_map, 1, _RET_IP_); smp_wmb(); s->sequence++; } @@ -188,7 +253,7 @@ typedef struct { */ #define __SEQLOCK_UNLOCKED(lockname) \ { \ - .seqcount = SEQCNT_ZERO, \ + .seqcount = SEQCNT_ZERO(lockname), \ .lock = __SPIN_LOCK_UNLOCKED(lockname) \ } diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h index 8da8c4e87da3..7bfabd20204c 100644 --- a/include/linux/u64_stats_sync.h +++ b/include/linux/u64_stats_sync.h @@ -67,6 +67,13 @@ struct u64_stats_sync { #endif }; + +#if BITS_PER_LONG == 32 && defined(CONFIG_SMP) +# define u64_stats_init(syncp) seqcount_init(syncp.seq) +#else +# define u64_stats_init(syncp) do { } while (0) +#endif + static inline void u64_stats_update_begin(struct u64_stats_sync *syncp) { #if BITS_PER_LONG==32 && defined(CONFIG_SMP) diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h index 613381bcde40..04c308413a5d 100644 --- a/include/trace/events/sched.h +++ b/include/trace/events/sched.h @@ -424,6 +424,25 @@ TRACE_EVENT(sched_pi_setprio, __entry->oldprio, __entry->newprio) ); +#ifdef CONFIG_DETECT_HUNG_TASK +TRACE_EVENT(sched_process_hang, + TP_PROTO(struct task_struct *tsk), + TP_ARGS(tsk), + + TP_STRUCT__entry( + __array( char, comm, TASK_COMM_LEN ) + __field( pid_t, pid ) + ), + + TP_fast_assign( + memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN); + __entry->pid = tsk->pid; + ), + + TP_printk("comm=%s pid=%d", __entry->comm, __entry->pid) +); +#endif /* CONFIG_DETECT_HUNG_TASK */ + #endif /* _TRACE_SCHED_H */ /* This part must be outside protection */ |