Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * RT-Mutexes: blocking mutual exclusion locks with PI support
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * started by Ingo Molnar and Thomas Gleixner:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *  Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  *  Copyright (C) 2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  * This code is based on the rt.c implementation in the preempt-rt tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  * Portions of said code are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13)  *  Copyright (C) 2004  LynuxWorks, Inc., Igor Manyilov, Bill Huey
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14)  *  Copyright (C) 2006  Esben Nielsen
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15)  *  Copyright (C) 2006  Kihon Technologies Inc.,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16)  *			Steven Rostedt <rostedt@goodmis.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18)  * See rt.c in preempt-rt for proper credits and further information
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <linux/sched/rt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <linux/sched/debug.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <linux/spinlock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) #include <linux/kallsyms.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) #include <linux/syscalls.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) #include <linux/rbtree.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) #include <linux/debug_locks.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) #include "rtmutex_common.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) static void printk_task(struct task_struct *p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	if (p)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 		printk("%16s:%5d [%p, %3d]", p->comm, task_pid_nr(p), p, p->prio);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 		printk("<none>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) static void printk_lock(struct rt_mutex *lock, int print_owner)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	if (lock->name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 		printk(" [%p] {%s}\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 			lock, lock->name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 		printk(" [%p] {%s:%d}\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 			lock, lock->file, lock->line);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	if (print_owner && rt_mutex_owner(lock)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 		printk(".. ->owner: %p\n", lock->owner);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 		printk(".. held by:  ");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 		printk_task(rt_mutex_owner(lock));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 		printk("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) void rt_mutex_debug_task_free(struct task_struct *task)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67)  * We fill out the fields in the waiter to store the information about
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68)  * the deadlock. We print when we return. act_waiter can be NULL in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69)  * case of a remove waiter operation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) void debug_rt_mutex_deadlock(enum rtmutex_chainwalk chwalk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 			     struct rt_mutex_waiter *act_waiter,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 			     struct rt_mutex *lock)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	struct task_struct *task;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	if (!debug_locks || chwalk == RT_MUTEX_FULL_CHAINWALK || !act_waiter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	task = rt_mutex_owner(act_waiter->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	if (task && task != current) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		act_waiter->deadlock_task_pid = get_pid(task_pid(task));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 		act_waiter->deadlock_lock = lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	struct task_struct *task;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	if (!waiter->deadlock_lock || !debug_locks)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	task = pid_task(waiter->deadlock_task_pid, PIDTYPE_PID);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	if (!task) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	if (!debug_locks_off()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	pr_warn("\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	pr_warn("============================================\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	pr_warn("WARNING: circular locking deadlock detected!\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	pr_warn("%s\n", print_tainted());
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	pr_warn("--------------------------------------------\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	printk("%s/%d is deadlocking current task %s/%d\n\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	       task->comm, task_pid_nr(task),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	       current->comm, task_pid_nr(current));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 	printk("\n1) %s/%d is trying to acquire this lock:\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	       current->comm, task_pid_nr(current));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	printk_lock(waiter->lock, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	printk("\n2) %s/%d is blocked on this lock:\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 		task->comm, task_pid_nr(task));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	printk_lock(waiter->deadlock_lock, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	debug_show_held_locks(current);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	debug_show_held_locks(task);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	printk("\n%s/%d's [blocked] stackdump:\n\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		task->comm, task_pid_nr(task));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	show_stack(task, NULL, KERN_DEFAULT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	printk("\n%s/%d's [current] stackdump:\n\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 		current->comm, task_pid_nr(current));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	dump_stack();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	debug_show_all_locks();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	printk("[ turning off deadlock detection."
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	       "Please report this trace. ]\n\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) void debug_rt_mutex_lock(struct rt_mutex *lock)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) void debug_rt_mutex_unlock(struct rt_mutex *lock)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) void
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) debug_rt_mutex_proxy_lock(struct rt_mutex *lock, struct task_struct *powner)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	DEBUG_LOCKS_WARN_ON(!rt_mutex_owner(lock));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	memset(waiter, 0x11, sizeof(*waiter));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	waiter->deadlock_task_pid = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	put_pid(waiter->deadlock_task_pid);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	memset(waiter, 0x22, sizeof(*waiter));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) void debug_rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	 * Make sure we are not reinitializing a held lock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	lock->name = name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) #ifdef CONFIG_DEBUG_LOCK_ALLOC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	lockdep_init_map(&lock->dep_map, name, key, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)