Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
locking/osq_lock: Clarify osq_wait_next()
Directly return NULL or 'next' instead of breaking out of the loop.
Signed-off-by: David Laight <david.laight@aculab.com>
[ Split original patch into two independent parts - Linus ]
Link: https://lore.kernel.org/lkml/7c8828aec72e42eeb841ca0ee3397e9a@AcuMS.aculab.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
authored by
David Laight
and committed by
Linus Torvalds
b106bcf0
563adbfc
+4
-5
+4
-5
kernel/locking/osq_lock.c
+4
-5
kernel/locking/osq_lock.c
···
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struct optimistic_spin_node *node,
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int old_cpu)
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{
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-
struct optimistic_spin_node *next = NULL;
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int curr = encode_cpu(smp_processor_id());
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for (;;) {
···
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* will now observe @lock and will complete its
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* unlock()/unqueue().
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*/
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-
break;
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return NULL;
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}
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/*
···
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* wait for a new @node->next from its Step-C.
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*/
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if (node->next) {
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struct optimistic_spin_node *next;
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next = xchg(&node->next, NULL);
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if (next)
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break;
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return next;
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}
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cpu_relax();
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}
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-
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return next;
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}
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bool osq_lock(struct optimistic_spin_queue *lock)