Improve approximation of style(9).
This commit is contained in:
Robert Watson
parent
fad788b1dc
commit
d02add54ea
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=191539
@ -55,25 +55,23 @@ __FBSDID("$FreeBSD$");
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#ifdef DDB
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#include <ddb/ddb.h>
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#endif
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#define RMPF_ONQUEUE 1
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#define RMPF_SIGNAL 2
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/*
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* To support usage of rmlock in CVs and msleep
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* yet another list for the priority tracker
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* would be needed.
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* Using this lock for cv and msleep also does
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* not seem very useful
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/*
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* To support usage of rmlock in CVs and msleep yet another list for the
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* priority tracker would be needed. Using this lock for cv and msleep also
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* does not seem very useful
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*/
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static __inline void compiler_memory_barrier(void) {
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__asm __volatile("":::"memory");
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}
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static void assert_rm(struct lock_object *lock, int what);
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static void lock_rm(struct lock_object *lock, int how);
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static int unlock_rm(struct lock_object *lock);
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static void assert_rm(struct lock_object *lock, int what);
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static void lock_rm(struct lock_object *lock, int how);
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static int unlock_rm(struct lock_object *lock);
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struct lock_class lock_class_rm = {
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.lc_name = "rm",
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@ -96,12 +94,16 @@ assert_rm(struct lock_object *lock, int what)
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}
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static void
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lock_rm(struct lock_object *lock, int how) {
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lock_rm(struct lock_object *lock, int how)
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{
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panic("lock_rm called");
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}
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static int
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unlock_rm(struct lock_object *lock) {
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unlock_rm(struct lock_object *lock)
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{
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panic("unlock_rm called");
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}
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@ -111,75 +113,79 @@ MTX_SYSINIT(rm_spinlock, &rm_spinlock, "rm_spinlock", MTX_SPIN);
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/*
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* Add or remove tracker from per cpu list.
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* The per cpu list can be traversed at any time in forward
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* direction from an interrupt on the *local* cpu.
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*
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* The per cpu list can be traversed at any time in forward direction from an
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* interrupt on the *local* cpu.
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*/
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static void inline
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rm_tracker_add(struct pcpu *pc, struct rm_priotracker* tracker) {
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struct rm_queue* next;
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static void inline
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rm_tracker_add(struct pcpu *pc, struct rm_priotracker *tracker)
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{
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struct rm_queue *next;
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/* Initialize all tracker pointers */
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tracker->rmp_cpuQueue.rmq_prev = &pc->pc_rm_queue;
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next = pc->pc_rm_queue.rmq_next;
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tracker->rmp_cpuQueue.rmq_next = next;
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/* rmq_prev is not used during froward traversal */
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/* rmq_prev is not used during froward traversal. */
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next->rmq_prev = &tracker->rmp_cpuQueue;
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/* Update pointer to first element */
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/* Update pointer to first element. */
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pc->pc_rm_queue.rmq_next = &tracker->rmp_cpuQueue;
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}
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static void inline
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rm_tracker_remove(struct pcpu *pc, struct rm_priotracker* tracker) {
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static void inline
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rm_tracker_remove(struct pcpu *pc, struct rm_priotracker *tracker)
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{
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struct rm_queue *next, *prev;
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next = tracker->rmp_cpuQueue.rmq_next;
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prev = tracker->rmp_cpuQueue.rmq_prev;
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/* Not used during forward traversal */
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next = tracker->rmp_cpuQueue.rmq_next;
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prev = tracker->rmp_cpuQueue.rmq_prev;
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/* Not used during forward traversal. */
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next->rmq_prev = prev;
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/* Remove from list */
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/* Remove from list. */
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prev->rmq_next = next;
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}
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static void rm_cleanIPI(void *arg) {
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static void
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rm_cleanIPI(void *arg)
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{
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struct pcpu *pc;
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struct rmlock* rm = arg;
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struct rmlock *rm = arg;
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struct rm_priotracker *tracker;
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struct rm_queue* queue;
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struct rm_queue *queue;
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pc = pcpu_find(curcpu);
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for(queue = pc->pc_rm_queue.rmq_next;
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queue != &pc->pc_rm_queue;
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for (queue = pc->pc_rm_queue.rmq_next; queue != &pc->pc_rm_queue;
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queue = queue->rmq_next) {
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tracker = (struct rm_priotracker *) queue;
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if(tracker->rmp_rmlock == rm && tracker->rmp_flags == 0 ) {
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tracker = (struct rm_priotracker *)queue;
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if (tracker->rmp_rmlock == rm && tracker->rmp_flags == 0) {
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tracker->rmp_flags = RMPF_ONQUEUE;
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mtx_lock_spin(&rm_spinlock);
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LIST_INSERT_HEAD(&rm->rm_activeReaders,tracker,
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LIST_INSERT_HEAD(&rm->rm_activeReaders, tracker,
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rmp_qentry);
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mtx_unlock_spin(&rm_spinlock);
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}
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}
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return;
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}
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void
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rm_init(struct rmlock *rm, const char *name, int opts)
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{
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rm->rm_noreadtoken = 1;
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LIST_INIT(&rm->rm_activeReaders);
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mtx_init(&rm->rm_lock, name, "RM_MTX",MTX_NOWITNESS);
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lock_init(&rm->lock_object, &lock_class_rm, name, NULL, (opts & LO_RECURSABLE)| LO_WITNESS);
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lock_init(&rm->lock_object, &lock_class_rm, name, NULL,
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(opts & LO_RECURSABLE)| LO_WITNESS);
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}
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void
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rm_destroy(struct rmlock *rm)
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{
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mtx_destroy(&rm->rm_lock);
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lock_destroy(&rm->lock_object);
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}
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@ -194,71 +200,64 @@ rm_wowned(struct rmlock *rm)
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void
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rm_sysinit(void *arg)
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{
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struct rm_args *args = arg;
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rm_init(args->ra_rm, args->ra_desc, args->ra_opts);
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}
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static void
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_rm_rlock_hard(struct rmlock *rm, struct rm_priotracker* tracker)
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_rm_rlock_hard(struct rmlock *rm, struct rm_priotracker *tracker)
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{
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struct pcpu *pc;
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struct rm_queue *queue;
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struct rm_priotracker* atracker;
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struct rm_priotracker *atracker;
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critical_enter();
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pc = pcpu_find(curcpu);
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/* Check if we just need to do a proper critical_exit */
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/* Check if we just need to do a proper critical_exit. */
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if (0 == rm->rm_noreadtoken) {
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critical_exit();
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return;
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}
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/* Remove our tracker from the per cpu list */
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rm_tracker_remove(pc,tracker);
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/* Remove our tracker from the per cpu list. */
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rm_tracker_remove(pc, tracker);
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/* Check to see if the IPI granted us the lock after all */
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if(tracker->rmp_flags) {
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/* Just add back tracker - we hold the lock */
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rm_tracker_add(pc,tracker);
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/* Check to see if the IPI granted us the lock after all. */
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if (tracker->rmp_flags) {
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/* Just add back tracker - we hold the lock. */
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rm_tracker_add(pc, tracker);
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critical_exit();
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return;
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}
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/*
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* We allow readers to aquire a lock even if a writer
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* is blocked if the lock is recursive and the reader
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* already holds the lock
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* We allow readers to aquire a lock even if a writer is blocked if
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* the lock is recursive and the reader already holds the lock.
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*/
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if ((rm->lock_object.lo_flags & LO_RECURSABLE) != 0) {
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/*
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* Just grand the lock if this thread already have a tracker
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* for this lock on the per cpu queue
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* for this lock on the per cpu queue.
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*/
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for(queue = pc->pc_rm_queue.rmq_next;
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queue != &pc->pc_rm_queue;
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queue = queue->rmq_next) {
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atracker = (struct rm_priotracker *) queue;
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if (( atracker->rmp_rmlock == rm) &&
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( atracker->rmp_thread == tracker->rmp_thread )) {
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for (queue = pc->pc_rm_queue.rmq_next;
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queue != &pc->pc_rm_queue; queue = queue->rmq_next) {
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atracker = (struct rm_priotracker *)queue;
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if ((atracker->rmp_rmlock == rm) &&
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(atracker->rmp_thread == tracker->rmp_thread)) {
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mtx_lock_spin(&rm_spinlock);
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LIST_INSERT_HEAD(&rm->rm_activeReaders,tracker,
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rmp_qentry);
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LIST_INSERT_HEAD(&rm->rm_activeReaders,
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tracker, rmp_qentry);
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tracker->rmp_flags = RMPF_ONQUEUE;
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mtx_unlock_spin(&rm_spinlock);
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rm_tracker_add(pc,tracker);
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rm_tracker_add(pc, tracker);
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critical_exit();
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return;
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}
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}
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}
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sched_unpin();
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critical_exit();
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@ -267,16 +266,15 @@ _rm_rlock_hard(struct rmlock *rm, struct rm_priotracker* tracker)
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critical_enter();
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pc = pcpu_find(curcpu);
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rm_tracker_add(pc,tracker);
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rm_tracker_add(pc, tracker);
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sched_pin();
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critical_exit();
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mtx_unlock(&rm->rm_lock);
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return;
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}
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void
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_rm_rlock(struct rmlock *rm, struct rm_priotracker* tracker)
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_rm_rlock(struct rmlock *rm, struct rm_priotracker *tracker)
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{
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struct thread *td = curthread;
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struct pcpu *pc;
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@ -291,51 +289,46 @@ _rm_rlock(struct rmlock *rm, struct rm_priotracker* tracker)
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pc = cpuid_to_pcpu[td->td_oncpu]; /* pcpu_find(td->td_oncpu); */
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rm_tracker_add(pc,tracker);
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rm_tracker_add(pc, tracker);
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td->td_pinned++; /* sched_pin(); */
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compiler_memory_barrier();
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td->td_critnest--;
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/*
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* Fast path to combine two common conditions
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* into a single conditional jump
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*/
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if (0 == (td->td_owepreempt | rm->rm_noreadtoken)) {
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return;
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}
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/* We do not have a read token and need to acquire one */
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_rm_rlock_hard(rm,tracker);
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/*
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* Fast path to combine two common conditions into a single
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* conditional jump.
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*/
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if (0 == (td->td_owepreempt | rm->rm_noreadtoken))
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return;
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/* We do not have a read token and need to acquire one. */
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_rm_rlock_hard(rm, tracker);
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}
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static void
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_rm_unlock_hard(struct thread *td,struct rm_priotracker* tracker)
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_rm_unlock_hard(struct thread *td,struct rm_priotracker *tracker)
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{
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if (td->td_owepreempt) {
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td->td_critnest++;
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critical_exit();
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}
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if (!tracker->rmp_flags) {
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if (!tracker->rmp_flags)
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return;
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}
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mtx_lock_spin(&rm_spinlock);
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LIST_REMOVE(tracker,rmp_qentry);
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LIST_REMOVE(tracker, rmp_qentry);
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if (tracker->rmp_flags & RMPF_SIGNAL) {
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struct rmlock *rm;
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struct turnstile* ts;
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struct turnstile *ts;
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rm = tracker->rmp_rmlock;
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turnstile_chain_lock(&rm->lock_object);
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mtx_unlock_spin(&rm_spinlock);
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@ -344,35 +337,28 @@ _rm_unlock_hard(struct thread *td,struct rm_priotracker* tracker)
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turnstile_signal(ts, TS_EXCLUSIVE_QUEUE);
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turnstile_unpend(ts, TS_EXCLUSIVE_LOCK);
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turnstile_chain_unlock(&rm->lock_object);
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} else
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mtx_unlock_spin(&rm_spinlock);
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}
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}
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void
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_rm_runlock(struct rmlock *rm, struct rm_priotracker* tracker)
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_rm_runlock(struct rmlock *rm, struct rm_priotracker *tracker)
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{
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struct pcpu *pc;
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struct thread *td = tracker->rmp_thread;
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td->td_critnest++; /* critical_enter(); */
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pc = cpuid_to_pcpu[td->td_oncpu]; /* pcpu_find(td->td_oncpu); */
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rm_tracker_remove(pc,tracker);
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rm_tracker_remove(pc, tracker);
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td->td_critnest--;
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td->td_pinned--; /* sched_unpin(); */
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if (0 == (td->td_owepreempt | tracker->rmp_flags))
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if (0 == (td->td_owepreempt | tracker->rmp_flags))
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return;
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_rm_unlock_hard(td,tracker);
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_rm_unlock_hard(td, tracker);
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}
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void
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_rm_wlock(struct rmlock *rm)
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{
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@ -386,53 +372,46 @@ _rm_wlock(struct rmlock *rm)
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rm->rm_noreadtoken = 1;
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/*
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* Assumes rm->rm_noreadtoken update is visible
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* on other CPUs before rm_cleanIPI is called
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/*
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* Assumes rm->rm_noreadtoken update is visible on other CPUs
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* before rm_cleanIPI is called.
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*/
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#ifdef SMP
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smp_rendezvous(smp_no_rendevous_barrier,
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rm_cleanIPI,
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smp_no_rendevous_barrier
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,rm);
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smp_no_rendevous_barrier,
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rm);
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#else
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rm_cleanIPI(rm);
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#endif
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mtx_lock_spin(&rm_spinlock);
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while((prio = LIST_FIRST(&rm->rm_activeReaders)) != NULL) {
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while ((prio = LIST_FIRST(&rm->rm_activeReaders)) != NULL) {
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ts = turnstile_trywait(&rm->lock_object);
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prio->rmp_flags = RMPF_ONQUEUE | RMPF_SIGNAL;
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mtx_unlock_spin(&rm_spinlock);
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turnstile_wait(ts,prio->rmp_thread,
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TS_EXCLUSIVE_QUEUE);
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turnstile_wait(ts, prio->rmp_thread,
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TS_EXCLUSIVE_QUEUE);
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mtx_lock_spin(&rm_spinlock);
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}
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mtx_unlock_spin(&rm_spinlock);
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}
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}
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void
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_rm_wunlock(struct rmlock *rm)
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{
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mtx_unlock(&rm->rm_lock);
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}
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#ifdef LOCK_DEBUG
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void _rm_wlock_debug(struct rmlock *rm, const char *file, int line)
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{
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WITNESS_CHECKORDER(&rm->lock_object, LOP_NEWORDER | LOP_EXCLUSIVE,
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WITNESS_CHECKORDER(&rm->lock_object, LOP_NEWORDER | LOP_EXCLUSIVE,
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file, line, NULL);
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_rm_wlock(rm);
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@ -445,71 +424,75 @@ void _rm_wlock_debug(struct rmlock *rm, const char *file, int line)
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}
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void _rm_wunlock_debug(struct rmlock *rm, const char *file, int line)
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void
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_rm_wunlock_debug(struct rmlock *rm, const char *file, int line)
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{
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curthread->td_locks--;
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WITNESS_UNLOCK(&rm->lock_object, LOP_EXCLUSIVE, file, line);
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LOCK_LOG_LOCK("RMWUNLOCK", &rm->lock_object, 0, 0, file, line);
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_rm_wunlock(rm);
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}
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}
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void
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void
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_rm_rlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
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const char *file, int line)
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{
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WITNESS_CHECKORDER(&rm->lock_object, LOP_NEWORDER, file, line, NULL);
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WITNESS_CHECKORDER(&rm->lock_object, LOP_NEWORDER , file, line, NULL);
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_rm_rlock(rm, tracker);
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LOCK_LOG_LOCK("RMRLOCK", &rm->lock_object, 0, 0, file, line);
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WITNESS_LOCK(&rm->lock_object, 0 , file, line);
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WITNESS_LOCK(&rm->lock_object, 0, file, line);
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curthread->td_locks++;
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curthread->td_locks++;
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}
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void
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void
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_rm_runlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
|
||||
const char *file, int line) {
|
||||
const char *file, int line)
|
||||
{
|
||||
|
||||
curthread->td_locks--;
|
||||
WITNESS_UNLOCK(&rm->lock_object, 0 , file, line);
|
||||
WITNESS_UNLOCK(&rm->lock_object, 0, file, line);
|
||||
LOCK_LOG_LOCK("RMRUNLOCK", &rm->lock_object, 0, 0, file, line);
|
||||
_rm_runlock(rm, tracker);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
#else
|
||||
/*
|
||||
* Just strip out file and line arguments if no lock debugging is enabled
|
||||
* in the kernel - we are called from a kernel module.
|
||||
*/
|
||||
|
||||
|
||||
void _rm_wlock_debug(struct rmlock *rm, const char *file, int line)
|
||||
/*
|
||||
* Just strip out file and line arguments if no lock debugging is enabled in
|
||||
* the kernel - we are called from a kernel module.
|
||||
*/
|
||||
void
|
||||
_rm_wlock_debug(struct rmlock *rm, const char *file, int line)
|
||||
{
|
||||
|
||||
_rm_wlock(rm);
|
||||
}
|
||||
|
||||
void _rm_wunlock_debug(struct rmlock *rm, const char *file, int line)
|
||||
void
|
||||
_rm_wunlock_debug(struct rmlock *rm, const char *file, int line)
|
||||
{
|
||||
|
||||
_rm_wunlock(rm);
|
||||
}
|
||||
|
||||
void
|
||||
}
|
||||
|
||||
void
|
||||
_rm_rlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
|
||||
const char *file, int line)
|
||||
{
|
||||
|
||||
_rm_rlock(rm, tracker);
|
||||
}
|
||||
|
||||
void
|
||||
void
|
||||
_rm_runlock_debug(struct rmlock *rm, struct rm_priotracker *tracker,
|
||||
const char *file, int line) {
|
||||
|
||||
_rm_runlock(rm, tracker);
|
||||
}
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user