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* locking/lockdep: Clean up #ifdef checksArnd Bergmann2019-07-251-7/+6Star
| | | | | | | | | | | | | | | | | | | | | | | | As Will Deacon points out, CONFIG_PROVE_LOCKING implies TRACE_IRQFLAGS, so the conditions I added in the previous patch, and some others in the same file can be simplified by only checking for the former. No functional change. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Yuyang Du <duyuyang@gmail.com> Fixes: 886532aee3cd ("locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING") Link: https://lkml.kernel.org/r/20190628102919.2345242-1-arnd@arndb.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && ↵Arnd Bergmann2019-06-251-39/+34Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_PROVE_LOCKING The last cleanup patch triggered another issue, as now another function should be moved into the same section: kernel/locking/lockdep.c:3580:12: error: 'mark_lock' defined but not used [-Werror=unused-function] static int mark_lock(struct task_struct *curr, struct held_lock *this, Move mark_lock() into the same #ifdef section as its only caller, and remove the now-unused mark_lock_irq() stub helper. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yuyang Du <duyuyang@gmail.com> Fixes: 0d2cc3b34532 ("locking/lockdep: Move valid_state() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING") Link: https://lkml.kernel.org/r/20190617124718.1232976-1-arnd@arndb.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove unnecessary DEBUG_LOCKS_WARN_ON()Kobe Wu2019-06-171-1/+1
| | | | | | | | | | | | | | | | | | | DEBUG_LOCKS_WARN_ON() will turn off debug_locks and makes print_unlock_imbalance_bug() return directly. Remove a redundant whitespace. Signed-off-by: Kobe Wu <kobe-cp.wu@mediatek.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <linux-mediatek@lists.infradead.org> Cc: <wsd_upstream@mediatek.com> Cc: Eason Lin <eason-yh.lin@mediatek.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/1559217575-30298-1-git-send-email-kobe-cp.wu@mediatek.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Fix merging of hlocks with non-zero referencesImre Deak2019-06-031-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sequence static DEFINE_WW_CLASS(test_ww_class); struct ww_acquire_ctx ww_ctx; struct ww_mutex ww_lock_a; struct ww_mutex ww_lock_b; struct ww_mutex ww_lock_c; struct mutex lock_c; ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); ww_mutex_init(&ww_lock_c, &test_ww_class); mutex_init(&lock_c); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); ww_mutex_lock(&ww_lock_b, &ww_ctx); ww_mutex_lock(&ww_lock_c, &ww_ctx); mutex_unlock(&lock_c); (*) ww_mutex_unlock(&ww_lock_c); ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); ww_acquire_fini(&ww_ctx); (**) will trigger the following error in __lock_release() when calling mutex_release() at **: DEBUG_LOCKS_WARN_ON(depth <= 0) The problem is that the hlock merging happening at * updates the references for test_ww_class incorrectly to 3 whereas it should've updated it to 4 (representing all the instances for ww_ctx and ww_lock_[abc]). Fix this by updating the references during merging correctly taking into account that we can have non-zero references (both for the hlock that we merge into another hlock or for the hlock we are merging into). Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190524201509.9199-2-imre.deak@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Fix OOO unlock when hlocks need mergingImre Deak2019-06-031-12/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sequence static DEFINE_WW_CLASS(test_ww_class); struct ww_acquire_ctx ww_ctx; struct ww_mutex ww_lock_a; struct ww_mutex ww_lock_b; struct mutex lock_c; struct mutex lock_d; ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); mutex_init(&lock_c); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); ww_mutex_lock(&ww_lock_b, &ww_ctx); mutex_unlock(&lock_c); (*) ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); ww_acquire_fini(&ww_ctx); triggers the following WARN in __lock_release() when doing the unlock at *: DEBUG_LOCKS_WARN_ON(curr->lockdep_depth != depth - 1); The problem is that the WARN check doesn't take into account the merging of ww_lock_a and ww_lock_b which results in decreasing curr->lockdep_depth by 2 not only 1. Note that the following sequence doesn't trigger the WARN, since there won't be any hlock merging. ww_acquire_init(&ww_ctx, &test_ww_class); ww_mutex_init(&ww_lock_a, &test_ww_class); ww_mutex_init(&ww_lock_b, &test_ww_class); mutex_init(&lock_c); mutex_init(&lock_d); ww_mutex_lock(&ww_lock_a, &ww_ctx); mutex_lock(&lock_c); mutex_lock(&lock_d); ww_mutex_lock(&ww_lock_b, &ww_ctx); mutex_unlock(&lock_d); ww_mutex_unlock(&ww_lock_b); ww_mutex_unlock(&ww_lock_a); mutex_unlock(&lock_c); ww_acquire_fini(&ww_ctx); In general both of the above two sequences are valid and shouldn't trigger any lockdep warning. Fix this by taking the decrement due to the hlock merging into account during lock release and hlock class re-setting. Merging can't happen during lock downgrading since there won't be a new possibility to merge hlocks in that case, so add a WARN if merging still happens then. Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: ville.syrjala@linux.intel.com Link: https://lkml.kernel.org/r/20190524201509.9199-1-imre.deak@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove !dir in lock irq usage checkYuyang Du2019-06-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In mark_lock_irq(), the following checks are performed: ---------------------------------- | -> | unsafe | read unsafe | |----------------------------------| | safe | F B | F* B* | |----------------------------------| | read safe | F? B* | - | ---------------------------------- Where: F: check_usage_forwards B: check_usage_backwards *: check enabled by STRICT_READ_CHECKS ?: check enabled by the !dir condition From checking point of view, the special F? case does not make sense, whereas it perhaps is made for peroformance concern. As later patch will address this issue, remove this exception, which makes the checks consistent later. With STRICT_READ_CHECKS = 1 which is default, there is no functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-24-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Adjust new bit cases in mark_lockYuyang Du2019-06-031-14/+7Star
| | | | | | | | | | | | | | | | | | The new bit can be any possible lock usage except it is garbage, so the cases in switch can be made simpler. Warn early on if wrong usage bit is passed without taking locks. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-23-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Consolidate lock usage bit initializationYuyang Du2019-06-031-8/+14
| | | | | | | | | | | | | | | | | Lock usage bit initialization is consolidated into one function mark_usage(). Trivial readability improvement. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-22-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Check redundant dependency only when CONFIG_LOCKDEP_SMALLYuyang Du2019-06-031-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Peter has put it all sound and complete for the cause, I simply quote: "It (check_redundant) was added for cross-release (which has since been reverted) which would generate a lot of redundant links (IIRC) but having it makes the reports more convoluted -- basically, if we had an A-B-C relation, then A-C will not be added to the graph because it is already covered. This then means any report will include B, even though a shorter cycle might have been possible." This would increase the number of direct dependencies. For a simple workload (make clean; reboot; make vmlinux -j8), the data looks like this: CONFIG_LOCKDEP_SMALL: direct dependencies: 6926 !CONFIG_LOCKDEP_SMALL: direct dependencies: 9052 (+30.7%) Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-21-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Refactorize check_noncircular and check_redundantYuyang Du2019-06-031-44/+74
| | | | | | | | | | | | | | | | | | These two functions now handle different check results themselves. A new check_path function is added to check whether there is a path in the dependency graph. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-20-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove unused argument in __lock_releaseYuyang Du2019-06-031-2/+2
| | | | | | | | | | | | | | | | | The @nested is not used in __release_lock so remove it despite that it is not used in lock_release in the first place. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-19-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove redundant argument in check_deadlockYuyang Du2019-06-031-3/+3
| | | | | | | | | | | | | | | | | In check_deadlock(), the third argument read comes from the second argument hlock so that it can be removed. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-18-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Update comments on dependency searchYuyang Du2019-06-031-11/+10Star
| | | | | | | | | | | | | | | | | | The breadth-first search is implemented as flat-out non-recursive now, but the comments are still describing it as recursive, update the comments in that regard. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-16-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Avoid constant checks in __bfs by using offset referenceYuyang Du2019-06-031-12/+21
| | | | | | | | | | | | | | | | | | | | In search of a dependency in the lock graph, there is contant checks for forward or backward search. Directly reference the field offset of the struct that differentiates the type of search to avoid those checks. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-15-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Change the return type of __cq_dequeue()Yuyang Du2019-06-031-8/+13
| | | | | | | | | | | | | | | | | With the change, we can slightly adjust the code to iterate the queue in BFS search, which simplifies the code. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-14-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Change type of the element field in circular_queueYuyang Du2019-06-031-10/+14
| | | | | | | | | | | | | | | | | | | | The element field is an array in struct circular_queue to keep track of locks in the search. Making it the same type as the locks avoids type cast. Also fix a typo and elaborate the comment above struct circular_queue. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-13-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Update commentYuyang Du2019-06-031-3/+9
| | | | | | | | | | | | | | | | | A leftover comment is removed. While at it, add more explanatory comments. Such a trivial patch! Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-12-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove unused argument in validate_chain() and check_deadlock()Yuyang Du2019-06-031-8/+8
| | | | | | | | | | | | | | | | The lockdep_map argument in them is not used, remove it. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-11-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Change the range of class_idx in held_lock structYuyang Du2019-06-031-20/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | held_lock->class_idx is used to point to the class of the held lock. The index is shifted by 1 to make index 0 mean no class, which results in class index shifting back and forth but is not worth doing so. The reason is: (1) there will be no "no-class" held_lock to begin with, and (2) index 0 seems to be used for error checking, but if something wrong indeed happened, the index can't be counted on to distinguish it as that something won't set the class_idx to 0 on purpose to tell us it is wrong. Therefore, change the index to start from 0. This saves a lot of back-and-forth shifts and a class slot back to lock_classes. Since index 0 is now used for lock class, we change the initial chain key to -1 to avoid key collision, which is due to the fact that __jhash_mix(0, 0, 0) = 0. Actually, the initial chain key can be any arbitrary value other than 0. In addition, a bitmap is maintained to keep track of the used lock classes, and we check the validity of the held lock against that bitmap. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-10-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Define INITIAL_CHAIN_KEY for chain keys to start withYuyang Du2019-06-031-9/+9
| | | | | | | | | | | | | | | | | | Chain keys are computed using Jenkins hash function, which needs an initial hash to start with. Dedicate a macro to make this clear and configurable. A later patch changes this initial chain key. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-9-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Use lockdep_init_task for task initiation consistentlyYuyang Du2019-06-031-3/+8
| | | | | | | | | | | | | | | | | | Despite that there is a lockdep_init_task() which does nothing, lockdep initiates tasks by assigning lockdep fields and does so inconsistently. Fix this by using lockdep_init_task(). Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-8-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Print the right depth for chain key collisionYuyang Du2019-06-031-3/+4
| | | | | | | | | | | | | | | | | Since chains are separated by IRQ context, so when printing a chain the depth should be consistent with it. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-6-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove useless conditional macroYuyang Du2019-06-031-3/+3
| | | | | | | | | | | | | | | | | Since #defined(CONFIG_PROVE_LOCKING) is used in the scope of #ifdef CONFIG_PROVE_LOCKING, it can be removed. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-5-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Adjust lock usage bit character checksYuyang Du2019-06-031-5/+16
| | | | | | | | | | | | | | | | | | | | The lock usage bit characters are defined and determined with tricks. Add some explanation to make it a bit clearer, then adjust the logic to check the usage, which optimizes the code a bit. No functional change. Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-4-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Change all print_*() return type to voidYuyang Du2019-06-031-101/+108
| | | | | | | | | | | | | | | | | | | | | | | | | | | Since none of the print_*() function's return value is necessary, change their return type to void. No functional change. In cases where an invariable return value is used, this change slightly improves readability, i.e.: print_x(); return 0; is definitely better than: return print_x(); /* where print_x() always returns 0 */ Signed-off-by: Yuyang Du <duyuyang@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bvanassche@acm.org Cc: frederic@kernel.org Cc: ming.lei@redhat.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190506081939.74287-2-duyuyang@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Remove the unused print_lock_trace() functionAnders Roxell2019-05-241-4/+0Star
| | | | | | | | | | | | | | | | | | gcc warns that function print_lock_trace() is unused if CONFIG_PROVE_LOCKING isn't set: ../kernel/locking/lockdep.c:2820:13: warning: ‘print_lock_trace’ defined but not used [-Wunused-function] Rework so we remove the function if CONFIG_PROVE_LOCKING isn't set. Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: will.deacon@arm.com Fixes: c120bce78065 ("lockdep: Simplify stack trace handling") Link: http://lkml.kernel.org/r/20190516191326.27003-1-anders.roxell@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Don't complain about incorrect name for no validate classSebastian Andrzej Siewior2019-05-241-1/+2
| | | | | | | | | | | | | | | | | | | | | | | It is possible to ignore the validation for a certain lock by using: lockdep_set_novalidate_class() on it. Each invocation will assign a new name to the class it created for created __lockdep_no_validate__. That means that once lockdep_set_novalidate_class() has been used on two locks then class->name won't match lock->name for the first lock triggering the warning. So ignore changed non-matching ->name pointer for the special __lockdep_no_validate__ class. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20190517212234.32611-1-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* treewide: Add SPDX license identifier for missed filesThomas Gleixner2019-05-211-0/+1
| | | | | | | | | | | | | | | | | Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 's390-5.2-1' of ↵Linus Torvalds2019-05-071-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - Support for kernel address space layout randomization - Add support for kernel image signature verification - Convert s390 to the generic get_user_pages_fast code - Convert s390 to the stack unwind API analog to x86 - Add support for CPU directed interrupts for PCI devices - Provide support for MIO instructions to the PCI base layer, this will allow the use of direct PCI mappings in user space code - Add the basic KVM guest ultravisor interface for protected VMs - Add AT_HWCAP bits for several new hardware capabilities - Update the CPU measurement facility counter definitions to SVN 6 - Arnds cleanup patches for his quest to get LLVM compiles working - A vfio-ccw update with bug fixes and support for halt and clear - Improvements for the hardware TRNG code - Another round of cleanup for the QDIO layer - Numerous cleanups and bug fixes * tag 's390-5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (98 commits) s390/vdso: drop unnecessary cc-ldoption s390: fix clang -Wpointer-sign warnigns in boot code s390: drop CONFIG_VIRT_TO_BUS s390: boot, purgatory: pass $(CLANG_FLAGS) where needed s390: only build for new CPUs with clang s390: simplify disabled_wait s390/ftrace: use HAVE_FUNCTION_GRAPH_RET_ADDR_PTR s390/unwind: introduce stack unwind API s390/opcodes: add missing instructions to the disassembler s390/bug: add entry size to the __bug_table section s390: use proper expoline sections for .dma code s390/nospec: rename assembler generated expoline thunks s390: add missing ENDPROC statements to assembler functions locking/lockdep: check for freed initmem in static_obj() s390/kernel: add support for kernel address space layout randomization (KASLR) s390/kernel: introduce .dma sections s390/sclp: do not use static sccbs s390/kprobes: use static buffer for insn_page s390/kernel: convert SYSCALL and PGM_CHECK handlers to .quad s390/kernel: build a relocatable kernel ...
| * locking/lockdep: check for freed initmem in static_obj()Gerald Schaefer2019-04-291-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following warning occurred on s390: WARNING: CPU: 0 PID: 804 at kernel/locking/lockdep.c:1025 lockdep_register_key+0x30/0x150 This is because the check in static_obj() assumes that all memory within [_stext, _end] belongs to static objects, which at least for s390 isn't true. The init section is also part of this range, and freeing it allows the buddy allocator to allocate memory from it. We have virt == phys for the kernel on s390, so that such allocations would then have addresses within the range [_stext, _end]. To fix this, introduce arch_is_kernel_initmem_freed(), similar to arch_is_kernel_text/data(), and add it to the checks in static_obj(). This will always return 0 on architectures that do not define arch_is_kernel_initmem_freed. On s390, it will return 1 if initmem has been freed and the address is in the range [__init_begin, __init_end]. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | Merge branch 'locking-core-for-linus' of ↵Linus Torvalds2019-05-061-84/+183
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "Here are the locking changes in this cycle: - rwsem unification and simpler micro-optimizations to prepare for more intrusive (and more lucrative) scalability improvements in v5.3 (Waiman Long) - Lockdep irq state tracking flag usage cleanups (Frederic Weisbecker) - static key improvements (Jakub Kicinski, Peter Zijlstra) - misc updates, cleanups and smaller fixes" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) locking/lockdep: Remove unnecessary unlikely() locking/static_key: Don't take sleeping locks in __static_key_slow_dec_deferred() locking/static_key: Factor out the fast path of static_key_slow_dec() locking/static_key: Add support for deferred static branches locking/lockdep: Test all incompatible scenarios at once in check_irq_usage() locking/lockdep: Avoid bogus Clang warning locking/lockdep: Generate LOCKF_ bit composites locking/lockdep: Use expanded masks on find_usage_*() functions locking/lockdep: Map remaining magic numbers to lock usage mask names locking/lockdep: Move valid_state() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING locking/rwsem: Prevent unneeded warning during locking selftest locking/rwsem: Optimize rwsem structure for uncontended lock acquisition locking/rwsem: Enable lock event counting locking/lock_events: Don't show pvqspinlock events on bare metal locking/lock_events: Make lock_events available for all archs & other locks locking/qspinlock_stat: Introduce generic lockevent_*() counting APIs locking/rwsem: Enhance DEBUG_RWSEMS_WARN_ON() macro locking/rwsem: Add debug check for __down_read*() locking/rwsem: Micro-optimize rwsem_try_read_lock_unqueued() locking/rwsem: Move rwsem internal function declarations to rwsem-xadd.h ...
| * | locking/lockdep: Remove unnecessary unlikely()zhengbin2019-04-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DEBUG_LOCKS_WARN_ON() already contains an unlikely(), there is no need for another one. Signed-off-by: zhengbin <zhengbin13@huawei.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: houtao1@huawei.com Link: http://lkml.kernel.org/r/1556540791-23110-1-git-send-email-zhengbin13@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/lockdep: Test all incompatible scenarios at once in check_irq_usage()Frederic Weisbecker2019-04-291-67/+161
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | check_prev_add_irq() tests all incompatible scenarios one after the other while adding a lock (@next) to a tree dependency (@prev): LOCK_USED_IN_HARDIRQ vs LOCK_ENABLED_HARDIRQ LOCK_USED_IN_HARDIRQ_READ vs LOCK_ENABLED_HARDIRQ LOCK_USED_IN_SOFTIRQ vs LOCK_ENABLED_SOFTIRQ LOCK_USED_IN_SOFTIRQ_READ vs LOCK_ENABLED_SOFTIRQ Also for these four scenarios, we must at least iterate the @prev backward dependency. Then if it matches the relevant LOCK_USED_* bit, we must also iterate the @next forward dependency. Therefore in the best case we iterate 4 times, in the worst case 8 times. A different approach can let us divide the number of branch iterations by 4: 1) Iterate through @prev backward dependencies and accumulate all the IRQ uses in a single mask. In the best case where the current lock hasn't been used in IRQ, we stop here. 2) Iterate through @next forward dependencies and try to find a lock whose usage is exclusive to the accumulated usages gathered in the previous step. If we find one (call it @lockA), we have found an incompatible use, otherwise we stop here. Only bad locking scenario go further. So a sane verification stop here. 3) Iterate again through @prev backward dependency and find the lock whose usage matches @lockA in term of incompatibility. Call that lock @lockB. 4) Report the incompatible usages of @lockA and @lockB If no incompatible use is found, the verification never goes beyond step 2 which means at most two iterations. The following compares the execution measurements of the function check_prev_add_irq(): Number of calls | Avg (ns) | Stdev (ns) | Total time (ns) ------------------------------------------------------------------------ Mainline 8452 | 2652 | 11962 | 22415143 This patch 8452 | 1518 | 7090 | 12835602 Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190402160244.32434-5-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/lockdep: Use expanded masks on find_usage_*() functionsFrederic Weisbecker2019-04-181-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to optimize check_irq_usage() and factorize all the IRQ usage validations we'll need to be able to check multiple lock usage bits at once. Prepare the low level usage mask check functions for that purpose. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190402160244.32434-4-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/lockdep: Map remaining magic numbers to lock usage mask namesFrederic Weisbecker2019-04-181-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clarify the code with mapping some more constant numbers that haven't been named after their corresponding LOCK_USAGE_* symbol. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190402160244.32434-3-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/lockdep: Move valid_state() inside CONFIG_TRACE_IRQFLAGS && ↵Frederic Weisbecker2019-04-181-4/+6
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_PROVE_LOCKING valid_state() and print_usage_bug*() functions are not used beyond irq locking correctness checks under CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING. Sadly the "unused function" warning wouldn't fire because valid_state() is inline so the unused case has remained unseen until now. So move them inside the appropriate CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING section. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190402160244.32434-2-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'core-stacktrace-for-linus' of ↵Linus Torvalds2019-05-061-49/+38Star
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull stack trace updates from Ingo Molnar: "So Thomas looked at the stacktrace code recently and noticed a few weirdnesses, and we all know how such stories of crummy kernel code meeting German engineering perfection end: a 45-patch series to clean it all up! :-) Here's the changes in Thomas's words: 'Struct stack_trace is a sinkhole for input and output parameters which is largely pointless for most usage sites. In fact if embedded into other data structures it creates indirections and extra storage overhead for no benefit. Looking at all usage sites makes it clear that they just require an interface which is based on a storage array. That array is either on stack, global or embedded into some other data structure. Some of the stack depot usage sites are outright wrong, but fortunately the wrongness just causes more stack being used for nothing and does not have functional impact. Another oddity is the inconsistent termination of the stack trace with ULONG_MAX. It's pointless as the number of entries is what determines the length of the stored trace. In fact quite some call sites remove the ULONG_MAX marker afterwards with or without nasty comments about it. Not all architectures do that and those which do, do it inconsistenly either conditional on nr_entries == 0 or unconditionally. The following series cleans that up by: 1) Removing the ULONG_MAX termination in the architecture code 2) Removing the ULONG_MAX fixups at the call sites 3) Providing plain storage array based interfaces for stacktrace and stackdepot. 4) Cleaning up the mess at the callsites including some related cleanups. 5) Removing the struct stack_trace based interfaces This is not changing the struct stack_trace interfaces at the architecture level, but it removes the exposure to the generic code'" * 'core-stacktrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits) x86/stacktrace: Use common infrastructure stacktrace: Provide common infrastructure lib/stackdepot: Remove obsolete functions stacktrace: Remove obsolete functions livepatch: Simplify stack trace retrieval tracing: Remove the last struct stack_trace usage tracing: Simplify stack trace retrieval tracing: Make ftrace_trace_userstack() static and conditional tracing: Use percpu stack trace buffer more intelligently tracing: Simplify stacktrace retrieval in histograms lockdep: Simplify stack trace handling lockdep: Remove save argument from check_prev_add() lockdep: Remove unused trace argument from print_circular_bug() drm: Simplify stacktrace handling dm persistent data: Simplify stack trace handling dm bufio: Simplify stack trace retrieval btrfs: ref-verify: Simplify stack trace retrieval dma/debug: Simplify stracktrace retrieval fault-inject: Simplify stacktrace retrieval mm/page_owner: Simplify stack trace handling ...
| * | lockdep: Simplify stack trace handlingThomas Gleixner2019-04-291-27/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the indirection through struct stack_trace by using the storage array based interfaces and storing the information is a small lockdep specific data structure. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: linux-mm@kvack.org Cc: David Rientjes <rientjes@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: kasan-dev@googlegroups.com Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: iommu@lists.linux-foundation.org Cc: Robin Murphy <robin.murphy@arm.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: linux-btrfs@vger.kernel.org Cc: dm-devel@redhat.com Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: intel-gfx@lists.freedesktop.org Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Miroslav Benes <mbenes@suse.cz> Cc: linux-arch@vger.kernel.org Link: https://lkml.kernel.org/r/20190425094802.891724020@linutronix.de
| * | lockdep: Remove save argument from check_prev_add()Thomas Gleixner2019-04-291-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is only one caller which hands in save_trace as function pointer. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: linux-mm@kvack.org Cc: David Rientjes <rientjes@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: kasan-dev@googlegroups.com Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: iommu@lists.linux-foundation.org Cc: Robin Murphy <robin.murphy@arm.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: linux-btrfs@vger.kernel.org Cc: dm-devel@redhat.com Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: intel-gfx@lists.freedesktop.org Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Miroslav Benes <mbenes@suse.cz> Cc: linux-arch@vger.kernel.org Link: https://lkml.kernel.org/r/20190425094802.803362058@linutronix.de
| * | lockdep: Remove unused trace argument from print_circular_bug()Thomas Gleixner2019-04-291-5/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: linux-mm@kvack.org Cc: David Rientjes <rientjes@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: kasan-dev@googlegroups.com Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: iommu@lists.linux-foundation.org Cc: Robin Murphy <robin.murphy@arm.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Cc: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: linux-btrfs@vger.kernel.org Cc: dm-devel@redhat.com Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: intel-gfx@lists.freedesktop.org Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: dri-devel@lists.freedesktop.org Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Miroslav Benes <mbenes@suse.cz> Cc: linux-arch@vger.kernel.org Link: https://lkml.kernel.org/r/20190425094802.716274532@linutronix.de
| * | lockdep: Remove the ULONG_MAX stack trace hackeryThomas Gleixner2019-04-141-11/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No architecture terminates the stack trace with ULONG_MAX anymore. Remove the cruft. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Potapenko <glider@google.com> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190410103644.485737321@linutronix.de
* | | locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' againBart Van Assche2019-04-161-4/+5
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If lockdep_register_key() and lockdep_unregister_key() are called with debug_locks == false then the following warning is reported: WARNING: CPU: 2 PID: 15145 at kernel/locking/lockdep.c:4920 lockdep_unregister_key+0x1ad/0x240 That warning is reported because lockdep_unregister_key() ignores the value of 'debug_locks' and because the behavior of lockdep_register_key() depends on whether or not 'debug_locks' is set. Fix this inconsistency by making lockdep_unregister_key() take 'debug_locks' again into account. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: shenghui <shhuiw@foxmail.com> Fixes: 90c1cba2b3b3 ("locking/lockdep: Zap lock classes even with lock debugging disabled") Link: http://lkml.kernel.org/r/20190415170538.23491-1-bvanassche@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* / locking/lockdep: Zap lock classes even with lock debugging disabledBart Van Assche2019-04-101-17/+12Star
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following commit: a0b0fd53e1e6 ("locking/lockdep: Free lock classes that are no longer in use") changed the behavior of lockdep_free_key_range() from unconditionally zapping lock classes into only zapping lock classes if debug_lock == true. Not zapping lock classes if debug_lock == false leaves dangling pointers in several lockdep datastructures, e.g. lock_class::name in the all_lock_classes list. The shell command "cat /proc/lockdep" causes the kernel to iterate the all_lock_classes list. Hence the "unable to handle kernel paging request" cash that Shenghui encountered by running cat /proc/lockdep. Since the new behavior can cause cat /proc/lockdep to crash, restore the pre-v5.1 behavior. This patch avoids that cat /proc/lockdep triggers the following crash with debug_lock == false: BUG: unable to handle kernel paging request at fffffbfff40ca448 RIP: 0010:__asan_load1+0x28/0x50 Call Trace: string+0xac/0x180 vsnprintf+0x23e/0x820 seq_vprintf+0x82/0xc0 seq_printf+0x92/0xb0 print_name+0x34/0xb0 l_show+0x184/0x200 seq_read+0x59e/0x6c0 proc_reg_read+0x11f/0x170 __vfs_read+0x4d/0x90 vfs_read+0xc5/0x1f0 ksys_read+0xab/0x130 __x64_sys_read+0x43/0x50 do_syscall_64+0x71/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reported-by: shenghui <shhuiw@foxmail.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Fixes: a0b0fd53e1e6 ("locking/lockdep: Free lock classes that are no longer in use") # v5.1-rc1. Link: https://lkml.kernel.org/r/20190403233552.124673-1-bvanassche@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Only call init_rcu_head() after RCU has been initializedBart Van Assche2019-03-091-4/+11
| | | | | | | | | | | | | | | | | | | | | | | init_data_structures_once() is called for the first time before RCU has been initialized. Make sure that init_rcu_head() is called before the RCU head is used and after RCU has been initialized. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: longman@redhat.com Link: https://lkml.kernel.org/r/c20aa0f0-42ab-a884-d931-7d4ec2bf0cdc@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/lockdep: Avoid a Clang warningArnd Bergmann2019-03-091-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clang warns about a tentative array definition without a length: kernel/locking/lockdep.c:845:12: error: tentative array definition assumed to have one element [-Werror] There is no real reason to do this here, so just set the same length as in the real definition later in the same file. It has to be hidden in an #ifdef or annotated __maybe_unused though, to avoid the unused-variable warning if CONFIG_PROVE_LOCKING is disabled. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190307075222.3424524-1-arnd@arndb.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2019-03-061-1/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Lots of tooling updates - too many to list, here's a few highlights: - Various subcommand updates to 'perf trace', 'perf report', 'perf record', 'perf annotate', 'perf script', 'perf test', etc. - CPU and NUMA topology and affinity handling improvements, - HW tracing and HW support updates: - Intel PT updates - ARM CoreSight updates - vendor HW event updates - BPF updates - Tons of infrastructure updates, both on the build system and the library support side - Documentation updates. - ... and lots of other changes, see the changelog for details. Kernel side updates: - Tighten up kprobes blacklist handling, reduce the number of places where developers can install a kprobe and hang/crash the system. - Fix/enhance vma address filter handling. - Various PMU driver updates, small fixes and additions. - refcount_t conversions - BPF updates - error code propagation enhancements - misc other changes" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (238 commits) perf script python: Add Python3 support to syscall-counts-by-pid.py perf script python: Add Python3 support to syscall-counts.py perf script python: Add Python3 support to stat-cpi.py perf script python: Add Python3 support to stackcollapse.py perf script python: Add Python3 support to sctop.py perf script python: Add Python3 support to powerpc-hcalls.py perf script python: Add Python3 support to net_dropmonitor.py perf script python: Add Python3 support to mem-phys-addr.py perf script python: Add Python3 support to failed-syscalls-by-pid.py perf script python: Add Python3 support to netdev-times.py perf tools: Add perf_exe() helper to find perf binary perf script: Handle missing fields with -F +.. perf data: Add perf_data__open_dir_data function perf data: Add perf_data__(create_dir|close_dir) functions perf data: Fail check_backup in case of error perf data: Make check_backup work over directories perf tools: Add rm_rf_perf_data function perf tools: Add pattern name checking to rm_rf perf tools: Add depth checking to rm_rf perf data: Add global path holder ...
| * kprobes: Prohibit probing on lockdep functionsMasami Hiramatsu2019-02-131-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some lockdep functions can be involved in breakpoint handling and probing on those functions can cause a breakpoint recursion. Prohibit probing on those functions by blacklist. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrea Righi <righi.andrea@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/154998810578.31052.1680977921449292812.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | locking/lockdep: Add module_param to enable consistency checksPeter Zijlstra2019-02-281-13/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | And move the whole lot under CONFIG_DEBUG_LOCKDEP. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | locking/lockdep: Add support for dynamic keysBart Van Assche2019-02-281-8/+113
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A shortcoming of the current lockdep implementation is that it requires lock keys to be allocated statically. That forces all instances of lock objects that occur in a given data structure to share a lock key. Since lock dependency analysis groups lock objects per key sharing lock keys can cause false positive lockdep reports. Make it possible to avoid such false positive reports by allowing lock keys to be allocated dynamically. Require that dynamically allocated lock keys are registered before use by calling lockdep_register_key(). Complain about attempts to register the same lock key pointer twice without calling lockdep_unregister_key() between successive registration calls. The purpose of the new lock_keys_hash[] data structure that keeps track of all dynamic keys is twofold: - Verify whether the lockdep_register_key() and lockdep_unregister_key() functions are used correctly. - Avoid that lockdep_init_map() complains when encountering a dynamically allocated key. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: johannes.berg@intel.com Cc: tj@kernel.org Link: https://lkml.kernel.org/r/20190214230058.196511-19-bvanassche@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | locking/lockdep: Verify whether lock objects are small enough to be used as ↵Bart Van Assche2019-02-281-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | class keys Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: johannes.berg@intel.com Cc: tj@kernel.org Link: https://lkml.kernel.org/r/20190214230058.196511-18-bvanassche@acm.org Signed-off-by: Ingo Molnar <mingo@kernel.org>