From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Sun, 18 Feb 2018 23:35:41 +0000
Subject: [PATCH] locking: rwsem: spin faster
tweak rwsem owner spinning a bit
---
kernel/locking/rwsem.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 69aba4abe104..b4818ccad5de 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -707,6 +707,7 @@ rwsem_spin_on_owner(struct rw_semaphore *sem)
struct task_struct *new, *owner;
unsigned long flags, new_flags;
enum owner_state state;
+ int i = 0;
lockdep_assert_preemption_disabled();
@@ -743,7 +744,8 @@ rwsem_spin_on_owner(struct rw_semaphore *sem)
break;
}
- cpu_relax();
+ if (i++ > 1000)
+ cpu_relax();
}
return state;
--
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