diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt index 5746b0c77f3e..adc2184009c5 100644 --- a/Documentation/RCU/whatisRCU.txt +++ b/Documentation/RCU/whatisRCU.txt @@ -883,7 +883,7 @@ All: lockdep-checked RCU-protected pointer access rcu_access_pointer rcu_dereference_raw - rcu_lockdep_assert + RCU_LOCKDEP_WARN rcu_sleep_check RCU_NONIDLE diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index df919ff103c3..3d6b5269fb2e 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -54,9 +54,9 @@ static DEFINE_MUTEX(mce_chrdev_read_mutex); #define rcu_dereference_check_mce(p) \ ({ \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ - lockdep_is_held(&mce_chrdev_read_mutex), \ - "suspicious rcu_dereference_check_mce() usage"); \ + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \ + !lockdep_is_held(&mce_chrdev_read_mutex), \ + "suspicious rcu_dereference_check_mce() usage"); \ smp_load_acquire(&(p)); \ }) diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index f5791927aa64..c5a5231d1d11 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -136,7 +136,7 @@ enum ctx_state ist_enter(struct pt_regs *regs) preempt_count_add(HARDIRQ_OFFSET); /* This code is a bit fragile. Test it. */ - rcu_lockdep_assert(rcu_is_watching(), "ist_enter didn't work"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work"); return prev_state; } diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 677fb2843553..3b188f20b43f 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -110,8 +110,8 @@ static DEFINE_MUTEX(dev_opp_list_lock); #define opp_rcu_lockdep_assert() \ do { \ - rcu_lockdep_assert(rcu_read_lock_held() || \ - lockdep_is_held(&dev_opp_list_lock), \ + RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ + !lockdep_is_held(&dev_opp_list_lock), \ "Missing rcu_read_lock() or " \ "dev_opp_list_lock protection"); \ } while (0) diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index fbb88740634a..674e3e226465 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -86,8 +86,8 @@ static inline struct file *__fcheck_files(struct files_struct *files, unsigned i static inline struct file *fcheck_files(struct files_struct *files, unsigned int fd) { - rcu_lockdep_assert(rcu_read_lock_held() || - lockdep_is_held(&files->file_lock), + RCU_LOCKDEP_WARN(!rcu_read_lock_held() && + !lockdep_is_held(&files->file_lock), "suspicious rcu_dereference_check() usage"); return __fcheck_files(files, fd); } diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 33ec16b9c2ee..ff476515f716 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -536,6 +536,11 @@ static inline int rcu_read_lock_sched_held(void) #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */ +/* Deprecate rcu_lockdep_assert(): Use RCU_LOCKDEP_WARN() instead. */ +static inline void __attribute((deprecated)) deprecate_rcu_lockdep_assert(void) +{ +} + #ifdef CONFIG_PROVE_RCU /** @@ -546,17 +551,32 @@ static inline int rcu_read_lock_sched_held(void) #define rcu_lockdep_assert(c, s) \ do { \ static bool __section(.data.unlikely) __warned; \ + deprecate_rcu_lockdep_assert(); \ if (debug_lockdep_rcu_enabled() && !__warned && !(c)) { \ __warned = true; \ lockdep_rcu_suspicious(__FILE__, __LINE__, s); \ } \ } while (0) +/** + * RCU_LOCKDEP_WARN - emit lockdep splat if specified condition is met + * @c: condition to check + * @s: informative message + */ +#define RCU_LOCKDEP_WARN(c, s) \ + do { \ + static bool __section(.data.unlikely) __warned; \ + if (debug_lockdep_rcu_enabled() && !__warned && (c)) { \ + __warned = true; \ + lockdep_rcu_suspicious(__FILE__, __LINE__, s); \ + } \ + } while (0) + #if defined(CONFIG_PROVE_RCU) && !defined(CONFIG_PREEMPT_RCU) static inline void rcu_preempt_sleep_check(void) { - rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), - "Illegal context switch in RCU read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_lock_map), + "Illegal context switch in RCU read-side critical section"); } #else /* #ifdef CONFIG_PROVE_RCU */ static inline void rcu_preempt_sleep_check(void) @@ -567,15 +587,16 @@ static inline void rcu_preempt_sleep_check(void) #define rcu_sleep_check() \ do { \ rcu_preempt_sleep_check(); \ - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map), \ - "Illegal context switch in RCU-bh read-side critical section"); \ - rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map), \ - "Illegal context switch in RCU-sched read-side critical section"); \ + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map), \ + "Illegal context switch in RCU-bh read-side critical section"); \ + RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map), \ + "Illegal context switch in RCU-sched read-side critical section"); \ } while (0) #else /* #ifdef CONFIG_PROVE_RCU */ -#define rcu_lockdep_assert(c, s) do { } while (0) +#define rcu_lockdep_assert(c, s) deprecate_rcu_lockdep_assert() +#define RCU_LOCKDEP_WARN(c, s) do { } while (0) #define rcu_sleep_check() do { } while (0) #endif /* #else #ifdef CONFIG_PROVE_RCU */ @@ -606,13 +627,13 @@ static inline void rcu_preempt_sleep_check(void) ({ \ /* Dependency order vs. p above. */ \ typeof(*p) *________p1 = (typeof(*p) *__force)lockless_dereference(p); \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \ + RCU_LOCKDEP_WARN(!(c), "suspicious rcu_dereference_check() usage"); \ rcu_dereference_sparse(p, space); \ ((typeof(*p) __force __kernel *)(________p1)); \ }) #define __rcu_dereference_protected(p, c, space) \ ({ \ - rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \ + RCU_LOCKDEP_WARN(!(c), "suspicious rcu_dereference_protected() usage"); \ rcu_dereference_sparse(p, space); \ ((typeof(*p) __force __kernel *)(p)); \ }) @@ -836,8 +857,8 @@ static inline void rcu_read_lock(void) __rcu_read_lock(); __acquire(RCU); rcu_lock_acquire(&rcu_lock_map); - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_lock() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_lock() used illegally while idle"); } /* @@ -887,8 +908,8 @@ static inline void rcu_read_lock(void) */ static inline void rcu_read_unlock(void) { - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_unlock() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_unlock() used illegally while idle"); __release(RCU); __rcu_read_unlock(); rcu_lock_release(&rcu_lock_map); /* Keep acq info for rls diags. */ @@ -916,8 +937,8 @@ static inline void rcu_read_lock_bh(void) local_bh_disable(); __acquire(RCU_BH); rcu_lock_acquire(&rcu_bh_lock_map); - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_lock_bh() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_lock_bh() used illegally while idle"); } /* @@ -927,8 +948,8 @@ static inline void rcu_read_lock_bh(void) */ static inline void rcu_read_unlock_bh(void) { - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_unlock_bh() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_unlock_bh() used illegally while idle"); rcu_lock_release(&rcu_bh_lock_map); __release(RCU_BH); local_bh_enable(); @@ -952,8 +973,8 @@ static inline void rcu_read_lock_sched(void) preempt_disable(); __acquire(RCU_SCHED); rcu_lock_acquire(&rcu_sched_lock_map); - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_lock_sched() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_lock_sched() used illegally while idle"); } /* Used by lockdep and tracing: cannot be traced, cannot call lockdep. */ @@ -970,8 +991,8 @@ static inline notrace void rcu_read_lock_sched_notrace(void) */ static inline void rcu_read_unlock_sched(void) { - rcu_lockdep_assert(rcu_is_watching(), - "rcu_read_unlock_sched() used illegally while idle"); + RCU_LOCKDEP_WARN(!rcu_is_watching(), + "rcu_read_unlock_sched() used illegally while idle"); rcu_lock_release(&rcu_sched_lock_map); __release(RCU_SCHED); preempt_enable(); diff --git a/kernel/cgroup.c b/kernel/cgroup.c index f89d9292eee6..b89f3168411b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -107,8 +107,8 @@ static DEFINE_SPINLOCK(release_agent_path_lock); struct percpu_rw_semaphore cgroup_threadgroup_rwsem; #define cgroup_assert_mutex_or_rcu_locked() \ - rcu_lockdep_assert(rcu_read_lock_held() || \ - lockdep_is_held(&cgroup_mutex), \ + RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ + !lockdep_is_held(&cgroup_mutex), \ "cgroup_mutex or RCU read lock required"); /* diff --git a/kernel/pid.c b/kernel/pid.c index 4fd07d5b7baf..ca368793808e 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -451,9 +451,8 @@ EXPORT_SYMBOL(pid_task); */ struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns) { - rcu_lockdep_assert(rcu_read_lock_held(), - "find_task_by_pid_ns() needs rcu_read_lock()" - " protection"); + RCU_LOCKDEP_WARN(!rcu_read_lock_held(), + "find_task_by_pid_ns() needs rcu_read_lock() protection"); return pid_task(find_pid_ns(nr, ns), PIDTYPE_PID); } diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c index de35087c92a5..d3fcb2ec8536 100644 --- a/kernel/rcu/srcu.c +++ b/kernel/rcu/srcu.c @@ -415,11 +415,11 @@ static void __synchronize_srcu(struct srcu_struct *sp, int trycount) struct rcu_head *head = &rcu.head; bool done = false; - rcu_lockdep_assert(!lock_is_held(&sp->dep_map) && - !lock_is_held(&rcu_bh_lock_map) && - !lock_is_held(&rcu_lock_map) && - !lock_is_held(&rcu_sched_lock_map), - "Illegal synchronize_srcu() in same-type SRCU (or RCU) read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&sp->dep_map) || + lock_is_held(&rcu_bh_lock_map) || + lock_is_held(&rcu_lock_map) || + lock_is_held(&rcu_sched_lock_map), + "Illegal synchronize_srcu() in same-type SRCU (or in RCU) read-side critical section"); might_sleep(); init_completion(&rcu.completion); diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index c291bd65d2cb..d0471056d0af 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -191,10 +191,10 @@ static void rcu_process_callbacks(struct softirq_action *unused) */ void synchronize_sched(void) { - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map) && - !lock_is_held(&rcu_lock_map) && - !lock_is_held(&rcu_sched_lock_map), - "Illegal synchronize_sched() in RCU read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) || + lock_is_held(&rcu_lock_map) || + lock_is_held(&rcu_sched_lock_map), + "Illegal synchronize_sched() in RCU read-side critical section"); cond_resched(); } EXPORT_SYMBOL_GPL(synchronize_sched); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index cb64d7e13d24..0a73d26357a2 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -649,12 +649,12 @@ static void rcu_eqs_enter_common(long long oldval, bool user) * It is illegal to enter an extended quiescent state while * in an RCU read-side critical section. */ - rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), - "Illegal idle entry in RCU read-side critical section."); - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map), - "Illegal idle entry in RCU-bh read-side critical section."); - rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map), - "Illegal idle entry in RCU-sched read-side critical section."); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_lock_map), + "Illegal idle entry in RCU read-side critical section."); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map), + "Illegal idle entry in RCU-bh read-side critical section."); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map), + "Illegal idle entry in RCU-sched read-side critical section."); } /* @@ -3161,10 +3161,10 @@ static inline int rcu_blocking_is_gp(void) */ void synchronize_sched(void) { - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map) && - !lock_is_held(&rcu_lock_map) && - !lock_is_held(&rcu_sched_lock_map), - "Illegal synchronize_sched() in RCU-sched read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) || + lock_is_held(&rcu_lock_map) || + lock_is_held(&rcu_sched_lock_map), + "Illegal synchronize_sched() in RCU-sched read-side critical section"); if (rcu_blocking_is_gp()) return; if (rcu_gp_is_expedited()) @@ -3188,10 +3188,10 @@ EXPORT_SYMBOL_GPL(synchronize_sched); */ void synchronize_rcu_bh(void) { - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map) && - !lock_is_held(&rcu_lock_map) && - !lock_is_held(&rcu_sched_lock_map), - "Illegal synchronize_rcu_bh() in RCU-bh read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) || + lock_is_held(&rcu_lock_map) || + lock_is_held(&rcu_sched_lock_map), + "Illegal synchronize_rcu_bh() in RCU-bh read-side critical section"); if (rcu_blocking_is_gp()) return; if (rcu_gp_is_expedited()) diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index a983bc68a146..9e922f111d63 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -538,10 +538,10 @@ EXPORT_SYMBOL_GPL(call_rcu); */ void synchronize_rcu(void) { - rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map) && - !lock_is_held(&rcu_lock_map) && - !lock_is_held(&rcu_sched_lock_map), - "Illegal synchronize_rcu() in RCU read-side critical section"); + RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) || + lock_is_held(&rcu_lock_map) || + lock_is_held(&rcu_sched_lock_map), + "Illegal synchronize_rcu() in RCU read-side critical section"); if (!rcu_scheduler_active) return; if (rcu_gp_is_expedited()) diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index a0a0dd03c73a..47268fb1d27b 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -589,8 +589,8 @@ EXPORT_SYMBOL_GPL(call_rcu_tasks); void synchronize_rcu_tasks(void) { /* Complain if the scheduler has not started. */ - rcu_lockdep_assert(!rcu_scheduler_active, - "synchronize_rcu_tasks called too soon"); + RCU_LOCKDEP_WARN(rcu_scheduler_active, + "synchronize_rcu_tasks called too soon"); /* Wait for the grace period. */ wait_rcu_gp(call_rcu_tasks); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 78b4bad10081..5e73c79fadd0 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2200,8 +2200,8 @@ unsigned long to_ratio(u64 period, u64 runtime) #ifdef CONFIG_SMP inline struct dl_bw *dl_bw_of(int i) { - rcu_lockdep_assert(rcu_read_lock_sched_held(), - "sched RCU must be held"); + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), + "sched RCU must be held"); return &cpu_rq(i)->rd->dl_bw; } @@ -2210,8 +2210,8 @@ static inline int dl_bw_cpus(int i) struct root_domain *rd = cpu_rq(i)->rd; int cpus = 0; - rcu_lockdep_assert(rcu_read_lock_sched_held(), - "sched RCU must be held"); + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), + "sched RCU must be held"); for_each_cpu_and(i, rd->span, cpu_active_mask) cpus++; diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 4c4f06176f74..cb91c63b4f4a 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -338,20 +338,20 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq); #include #define assert_rcu_or_pool_mutex() \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ - lockdep_is_held(&wq_pool_mutex), \ - "sched RCU or wq_pool_mutex should be held") + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \ + !lockdep_is_held(&wq_pool_mutex), \ + "sched RCU or wq_pool_mutex should be held") #define assert_rcu_or_wq_mutex(wq) \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ - lockdep_is_held(&wq->mutex), \ - "sched RCU or wq->mutex should be held") + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \ + !lockdep_is_held(&wq->mutex), \ + "sched RCU or wq->mutex should be held") #define assert_rcu_or_wq_mutex_or_pool_mutex(wq) \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ - lockdep_is_held(&wq->mutex) || \ - lockdep_is_held(&wq_pool_mutex), \ - "sched RCU, wq->mutex or wq_pool_mutex should be held") + RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \ + !lockdep_is_held(&wq->mutex) && \ + !lockdep_is_held(&wq_pool_mutex), \ + "sched RCU, wq->mutex or wq_pool_mutex should be held") #define for_each_cpu_worker_pool(pool, cpu) \ for ((pool) = &per_cpu(cpu_worker_pools, cpu)[0]; \ diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 188c1d26393b..73455089feef 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -400,9 +400,9 @@ static bool verify_new_ex(struct dev_cgroup *dev_cgroup, { bool match = false; - rcu_lockdep_assert(rcu_read_lock_held() || - lockdep_is_held(&devcgroup_mutex), - "device_cgroup:verify_new_ex called without proper synchronization"); + RCU_LOCKDEP_WARN(!rcu_read_lock_held() && + lockdep_is_held(&devcgroup_mutex), + "device_cgroup:verify_new_ex called without proper synchronization"); if (dev_cgroup->behavior == DEVCG_DEFAULT_ALLOW) { if (behavior == DEVCG_DEFAULT_ALLOW) {