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lockdep: Use consistent printing primitives
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Commit a5dd63e ("lockdep: Use "WARNING" tag on lockdep splats")
substituted pr_warn() for printk() in places called out by Dmitry Vyukov.
However, this resulted in an ugly mix of pr_warn() and printk().  This
commit therefore changes printk() to pr_warn() or pr_cont(), depending
on the absence or presence of KERN_CONT.  This is done in all functions
that had printk() changed to pr_warn() by the aforementioned commit.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
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Paul E. McKenney committed Jun 9, 2017
1 parent 2464dd9 commit 681fbec
Showing 1 changed file with 86 additions and 86 deletions.
172 changes: 86 additions & 86 deletions kernel/locking/lockdep.c
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Original file line number Diff line number Diff line change
@@ -1157,18 +1157,18 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth,
if (debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("======================================================\n");
pr_warn("WARNING: possible circular locking dependency detected\n");
print_kernel_ident();
pr_warn("------------------------------------------------------\n");
printk("%s/%d is trying to acquire lock:\n",
pr_warn("%s/%d is trying to acquire lock:\n",
curr->comm, task_pid_nr(curr));
print_lock(check_src);
printk("\nbut task is already holding lock:\n");
pr_warn("\nbut task is already holding lock:\n");
print_lock(check_tgt);
printk("\nwhich lock already depends on the new lock.\n\n");
printk("\nthe existing dependency chain (in reverse order) is:\n");
pr_warn("\nwhich lock already depends on the new lock.\n\n");
pr_warn("\nthe existing dependency chain (in reverse order) is:\n");

print_circular_bug_entry(entry, depth);

@@ -1495,60 +1495,60 @@ print_bad_irq_dependency(struct task_struct *curr,
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("=====================================================\n");
pr_warn("WARNING: %s-safe -> %s-unsafe lock order detected\n",
irqclass, irqclass);
print_kernel_ident();
pr_warn("-----------------------------------------------------\n");
printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n",
pr_warn("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n",
curr->comm, task_pid_nr(curr),
curr->hardirq_context, hardirq_count() >> HARDIRQ_SHIFT,
curr->softirq_context, softirq_count() >> SOFTIRQ_SHIFT,
curr->hardirqs_enabled,
curr->softirqs_enabled);
print_lock(next);

printk("\nand this task is already holding:\n");
pr_warn("\nand this task is already holding:\n");
print_lock(prev);
printk("which would create a new lock dependency:\n");
pr_warn("which would create a new lock dependency:\n");
print_lock_name(hlock_class(prev));
printk(KERN_CONT " ->");
pr_cont(" ->");
print_lock_name(hlock_class(next));
printk(KERN_CONT "\n");
pr_cont("\n");

printk("\nbut this new dependency connects a %s-irq-safe lock:\n",
pr_warn("\nbut this new dependency connects a %s-irq-safe lock:\n",
irqclass);
print_lock_name(backwards_entry->class);
printk("\n... which became %s-irq-safe at:\n", irqclass);
pr_warn("\n... which became %s-irq-safe at:\n", irqclass);

print_stack_trace(backwards_entry->class->usage_traces + bit1, 1);

printk("\nto a %s-irq-unsafe lock:\n", irqclass);
pr_warn("\nto a %s-irq-unsafe lock:\n", irqclass);
print_lock_name(forwards_entry->class);
printk("\n... which became %s-irq-unsafe at:\n", irqclass);
printk("...");
pr_warn("\n... which became %s-irq-unsafe at:\n", irqclass);
pr_warn("...");

print_stack_trace(forwards_entry->class->usage_traces + bit2, 1);

printk("\nother info that might help us debug this:\n\n");
pr_warn("\nother info that might help us debug this:\n\n");
print_irq_lock_scenario(backwards_entry, forwards_entry,
hlock_class(prev), hlock_class(next));

lockdep_print_held_locks(curr);

printk("\nthe dependencies between %s-irq-safe lock and the holding lock:\n", irqclass);
pr_warn("\nthe dependencies between %s-irq-safe lock and the holding lock:\n", irqclass);
if (!save_trace(&prev_root->trace))
return 0;
print_shortest_lock_dependencies(backwards_entry, prev_root);

printk("\nthe dependencies between the lock to be acquired");
printk(" and %s-irq-unsafe lock:\n", irqclass);
pr_warn("\nthe dependencies between the lock to be acquired");
pr_warn(" and %s-irq-unsafe lock:\n", irqclass);
if (!save_trace(&next_root->trace))
return 0;
print_shortest_lock_dependencies(forwards_entry, next_root);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -1724,22 +1724,22 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev,
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("============================================\n");
pr_warn("WARNING: possible recursive locking detected\n");
print_kernel_ident();
pr_warn("--------------------------------------------\n");
printk("%s/%d is trying to acquire lock:\n",
pr_warn("%s/%d is trying to acquire lock:\n",
curr->comm, task_pid_nr(curr));
print_lock(next);
printk("\nbut task is already holding lock:\n");
pr_warn("\nbut task is already holding lock:\n");
print_lock(prev);

printk("\nother info that might help us debug this:\n");
pr_warn("\nother info that might help us debug this:\n");
print_deadlock_scenario(next, prev);
lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -2074,21 +2074,21 @@ static void print_collision(struct task_struct *curr,
struct held_lock *hlock_next,
struct lock_chain *chain)
{
printk("\n");
pr_warn("\n");
pr_warn("============================\n");
pr_warn("WARNING: chain_key collision\n");
print_kernel_ident();
pr_warn("----------------------------\n");
printk("%s/%d: ", current->comm, task_pid_nr(current));
printk("Hash chain already cached but the contents don't match!\n");
pr_warn("%s/%d: ", current->comm, task_pid_nr(current));
pr_warn("Hash chain already cached but the contents don't match!\n");

printk("Held locks:");
pr_warn("Held locks:");
print_chain_keys_held_locks(curr, hlock_next);

printk("Locks in cached chain:");
pr_warn("Locks in cached chain:");
print_chain_keys_chain(chain);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();
}
#endif
@@ -2373,33 +2373,33 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this,
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("================================\n");
pr_warn("WARNING: inconsistent lock state\n");
print_kernel_ident();
pr_warn("--------------------------------\n");

printk("inconsistent {%s} -> {%s} usage.\n",
pr_warn("inconsistent {%s} -> {%s} usage.\n",
usage_str[prev_bit], usage_str[new_bit]);

printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] takes:\n",
pr_warn("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] takes:\n",
curr->comm, task_pid_nr(curr),
trace_hardirq_context(curr), hardirq_count() >> HARDIRQ_SHIFT,
trace_softirq_context(curr), softirq_count() >> SOFTIRQ_SHIFT,
trace_hardirqs_enabled(curr),
trace_softirqs_enabled(curr));
print_lock(this);

printk("{%s} state was registered at:\n", usage_str[prev_bit]);
pr_warn("{%s} state was registered at:\n", usage_str[prev_bit]);
print_stack_trace(hlock_class(this)->usage_traces + prev_bit, 1);

print_irqtrace_events(curr);
printk("\nother info that might help us debug this:\n");
pr_warn("\nother info that might help us debug this:\n");
print_usage_bug_scenario(this);

lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -2438,28 +2438,28 @@ print_irq_inversion_bug(struct task_struct *curr,
if (!debug_locks_off_graph_unlock() || debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("========================================================\n");
pr_warn("WARNING: possible irq lock inversion dependency detected\n");
print_kernel_ident();
pr_warn("--------------------------------------------------------\n");
printk("%s/%d just changed the state of lock:\n",
pr_warn("%s/%d just changed the state of lock:\n",
curr->comm, task_pid_nr(curr));
print_lock(this);
if (forwards)
printk("but this lock took another, %s-unsafe lock in the past:\n", irqclass);
pr_warn("but this lock took another, %s-unsafe lock in the past:\n", irqclass);
else
printk("but this lock was taken by another, %s-safe lock in the past:\n", irqclass);
pr_warn("but this lock was taken by another, %s-safe lock in the past:\n", irqclass);
print_lock_name(other->class);
printk("\n\nand interrupts could create inverse lock ordering between them.\n\n");
pr_warn("\n\nand interrupts could create inverse lock ordering between them.\n\n");

printk("\nother info that might help us debug this:\n");
pr_warn("\nother info that might help us debug this:\n");

/* Find a middle lock (if one exists) */
depth = get_lock_depth(other);
do {
if (depth == 0 && (entry != root)) {
printk("lockdep:%s bad path found in chain graph\n", __func__);
pr_warn("lockdep:%s bad path found in chain graph\n", __func__);
break;
}
middle = entry;
@@ -2475,12 +2475,12 @@ print_irq_inversion_bug(struct task_struct *curr,

lockdep_print_held_locks(curr);

printk("\nthe shortest dependencies between 2nd lock and 1st lock:\n");
pr_warn("\nthe shortest dependencies between 2nd lock and 1st lock:\n");
if (!save_trace(&root->trace))
return 0;
print_shortest_lock_dependencies(other, root);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -3189,25 +3189,25 @@ print_lock_nested_lock_not_held(struct task_struct *curr,
if (debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("==================================\n");
pr_warn("WARNING: Nested lock was not taken\n");
print_kernel_ident();
pr_warn("----------------------------------\n");

printk("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr));
pr_warn("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr));
print_lock(hlock);

printk("\nbut this task is not holding:\n");
printk("%s\n", hlock->nest_lock->name);
pr_warn("\nbut this task is not holding:\n");
pr_warn("%s\n", hlock->nest_lock->name);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

printk("\nother info that might help us debug this:\n");
pr_warn("\nother info that might help us debug this:\n");
lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -3402,21 +3402,21 @@ print_unlock_imbalance_bug(struct task_struct *curr, struct lockdep_map *lock,
if (debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("=====================================\n");
pr_warn("WARNING: bad unlock balance detected!\n");
print_kernel_ident();
pr_warn("-------------------------------------\n");
printk("%s/%d is trying to release lock (",
pr_warn("%s/%d is trying to release lock (",
curr->comm, task_pid_nr(curr));
print_lockdep_cache(lock);
printk(KERN_CONT ") at:\n");
pr_cont(") at:\n");
print_ip_sym(ip);
printk("but there are no more locks to release!\n");
printk("\nother info that might help us debug this:\n");
pr_warn("but there are no more locks to release!\n");
pr_warn("\nother info that might help us debug this:\n");
lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -3974,21 +3974,21 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock,
if (debug_locks_silent)
return 0;

printk("\n");
pr_warn("\n");
pr_warn("=================================\n");
pr_warn("WARNING: bad contention detected!\n");
print_kernel_ident();
pr_warn("---------------------------------\n");
printk("%s/%d is trying to contend lock (",
pr_warn("%s/%d is trying to contend lock (",
curr->comm, task_pid_nr(curr));
print_lockdep_cache(lock);
printk(KERN_CONT ") at:\n");
pr_cont(") at:\n");
print_ip_sym(ip);
printk("but there are no locks held!\n");
printk("\nother info that might help us debug this:\n");
pr_warn("but there are no locks held!\n");
pr_warn("\nother info that might help us debug this:\n");
lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();

return 0;
@@ -4318,17 +4318,17 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from,
if (debug_locks_silent)
return;

printk("\n");
pr_warn("\n");
pr_warn("=========================\n");
pr_warn("WARNING: held lock freed!\n");
print_kernel_ident();
pr_warn("-------------------------\n");
printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n",
pr_warn("%s/%d is freeing memory %p-%p, with a lock still held there!\n",
curr->comm, task_pid_nr(curr), mem_from, mem_to-1);
print_lock(hlock);
lockdep_print_held_locks(curr);

printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();
}

@@ -4376,14 +4376,14 @@ static void print_held_locks_bug(void)
if (debug_locks_silent)
return;

printk("\n");
pr_warn("\n");
pr_warn("====================================\n");
pr_warn("WARNING: %s/%d still has locks held!\n",
current->comm, task_pid_nr(current));
print_kernel_ident();
pr_warn("------------------------------------\n");
lockdep_print_held_locks(current);
printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();
}

@@ -4402,10 +4402,10 @@ void debug_show_all_locks(void)
int unlock = 1;

if (unlikely(!debug_locks)) {
printk("INFO: lockdep is turned off.\n");
pr_warn("INFO: lockdep is turned off.\n");
return;
}
printk("\nShowing all locks held in the system:\n");
pr_warn("\nShowing all locks held in the system:\n");

/*
* Here we try to get the tasklist_lock as hard as possible,
@@ -4416,18 +4416,18 @@ void debug_show_all_locks(void)
retry:
if (!read_trylock(&tasklist_lock)) {
if (count == 10)
printk("hm, tasklist_lock locked, retrying... ");
pr_warn("hm, tasklist_lock locked, retrying... ");
if (count) {
count--;
printk(" #%d", 10-count);
pr_cont(" #%d", 10-count);
mdelay(200);
goto retry;
}
printk(" ignoring it.\n");
pr_cont(" ignoring it.\n");
unlock = 0;
} else {
if (count != 10)
printk(KERN_CONT " locked it.\n");
pr_cont(" locked it.\n");
}

do_each_thread(g, p) {
@@ -4445,7 +4445,7 @@ void debug_show_all_locks(void)
unlock = 1;
} while_each_thread(g, p);

printk("\n");
pr_warn("\n");
pr_warn("=============================================\n\n");

if (unlock)
@@ -4475,12 +4475,12 @@ asmlinkage __visible void lockdep_sys_exit(void)
if (unlikely(curr->lockdep_depth)) {
if (!debug_locks_off())
return;
printk("\n");
pr_warn("\n");
pr_warn("================================================\n");
pr_warn("WARNING: lock held when returning to user space!\n");
print_kernel_ident();
pr_warn("------------------------------------------------\n");
printk("%s/%d is leaving the kernel with locks still held!\n",
pr_warn("%s/%d is leaving the kernel with locks still held!\n",
curr->comm, curr->pid);
lockdep_print_held_locks(curr);
}
@@ -4495,14 +4495,14 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
return;
#endif /* #ifdef CONFIG_PROVE_RCU_REPEATEDLY */
/* Note: the following can be executed concurrently, so be careful. */
printk("\n");
pr_warn("\n");
pr_warn("=============================\n");
pr_warn("WARNING: suspicious RCU usage\n");
print_kernel_ident();
pr_warn("-----------------------------\n");
printk("%s:%d %s!\n", file, line, s);
printk("\nother info that might help us debug this:\n\n");
printk("\n%srcu_scheduler_active = %d, debug_locks = %d\n",
pr_warn("%s:%d %s!\n", file, line, s);
pr_warn("\nother info that might help us debug this:\n\n");
pr_warn("\n%srcu_scheduler_active = %d, debug_locks = %d\n",
!rcu_lockdep_current_cpu_online()
? "RCU used illegally from offline CPU!\n"
: !rcu_is_watching()
@@ -4529,10 +4529,10 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
* rcu_read_lock_bh() and so on from extended quiescent states.
*/
if (!rcu_is_watching())
printk("RCU used illegally from extended quiescent state!\n");
pr_warn("RCU used illegally from extended quiescent state!\n");

lockdep_print_held_locks(curr);
printk("\nstack backtrace:\n");
pr_warn("\nstack backtrace:\n");
dump_stack();
}
EXPORT_SYMBOL_GPL(lockdep_rcu_suspicious);

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