Commit 436a49ae authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Ingo Molnar
Browse files

locking/lockdep: Simplify mark_held_locks() 



The enum mark_type appears a bit artificial here. We can directly pass
the base enum lock_usage_bit value to mark_held_locks(). All we need
then is to add the read index for each lock if necessary. It makes the
code clearer.

Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: default avatarPeter 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/1545973321-24422-2-git-send-email-frederic@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent b5a4e2bb

kernel/locking/lockdep.c

+8 −15
Original line number Diff line number Diff line
@@ -2709,35 +2709,28 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, 
	return 1;

}



enum mark_type {

#define LOCKDEP_STATE(__STATE)	__STATE,

#include "lockdep_states.h"

#undef LOCKDEP_STATE

};



/*

 * Mark all held locks with a usage bit:

 */

static int

mark_held_locks(struct task_struct *curr, enum mark_type mark)

mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit)

{

	enum lock_usage_bit usage_bit;

	struct held_lock *hlock;

	int i;



	for (i = 0; i < curr->lockdep_depth; i++) {

		enum lock_usage_bit hlock_bit = base_bit;

		hlock = curr->held_locks + i;



		usage_bit = 2 + (mark << 2); /* ENABLED */

		if (hlock->read)

			usage_bit += 1; /* READ */

			hlock_bit += 1; /* READ */



		BUG_ON(usage_bit >= LOCK_USAGE_STATES);

		BUG_ON(hlock_bit >= LOCK_USAGE_STATES);



		if (!hlock->check)

			continue;



		if (!mark_lock(curr, hlock, usage_bit))

		if (!mark_lock(curr, hlock, hlock_bit))

			return 0;

	}
@@ -2758,7 +2751,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) 
	 * We are going to turn hardirqs on, so set the

	 * usage bit for all held locks:

	 */

	if (!mark_held_locks(curr, HARDIRQ))

	if (!mark_held_locks(curr, LOCK_ENABLED_HARDIRQ))

		return;

	/*

	 * If we have softirqs enabled, then set the usage
@@ -2766,7 +2759,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) 
	 * this bit from being set before)

	 */

	if (curr->softirqs_enabled)

		if (!mark_held_locks(curr, SOFTIRQ))

		if (!mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ))

			return;



	curr->hardirq_enable_ip = ip;
@@ -2880,7 +2873,7 @@ void trace_softirqs_on(unsigned long ip) 
	 * enabled too:

	 */

	if (curr->hardirqs_enabled)

		mark_held_locks(curr, SOFTIRQ);

		mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ);

	current->lockdep_recursion = 0;

}