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authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>2016-03-31 11:00:08 -0700
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>2016-03-31 13:33:23 -0700
commit0c7d10e4b998b2f751cebf98435f1ec2dd312c87 (patch)
tree9b488381e266ee5eac0ddc62fd4b805913c4196f /Documentation/RCU
parent5413e24c943da33306047fc091fa34fa4f261b3b (diff)
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documentation: Emphasize the call_rcu() is illegal from idle
Although call_rcu()'s fastpath works just fine on an idle CPU, some branches of the slowpath invoke the scheduler, which uses RCU. Therefore, this commit emphasizes the fact that call_rcu() must not be invoked from an idle CPU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'Documentation/RCU')
-rw-r--r--Documentation/RCU/Design/Requirements/Requirements.html2
1 files changed, 1 insertions, 1 deletions
diff --git a/Documentation/RCU/Design/Requirements/Requirements.html b/Documentation/RCU/Design/Requirements/Requirements.html
index 85cf223..e7e24b3 100644
--- a/Documentation/RCU/Design/Requirements/Requirements.html
+++ b/Documentation/RCU/Design/Requirements/Requirements.html
@@ -1650,7 +1650,7 @@ situations where neither <tt>synchronize_rcu()</tt> nor
including within preempt-disable code, <tt>local_bh_disable()</tt> code,
interrupt-disable code, and interrupt handlers.
However, even <tt>call_rcu()</tt> is illegal within NMI handlers
-and from offline CPUs.
+and from idle and offline CPUs.
The callback function (<tt>remove_gp_cb()</tt> in this case) will be
executed within softirq (software interrupt) environment within the
Linux kernel,
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