rcu/nocb: Use separate flag to indicate disabled ->cblist

NULLing the RCU_NEXT_TAIL pointer was a clever way to save a byte, but
forward-progress considerations would require that this pointer be both
NULL and non-NULL, which, absent a quantum-computer port of the Linux
kernel, simply won't happen.  This commit therefore creates as separate
->enabled flag to replace the current NULL checks.

[ paulmck: Add include files per 0day test robot and -next. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit is contained in:
Paul E. McKenney 2019-04-12 12:34:41 -07:00
parent 18cd8c93e6
commit 1bb5f9b95a
4 changed files with 8 additions and 3 deletions

View file

@ -14,6 +14,9 @@
#ifndef __INCLUDE_LINUX_RCU_SEGCBLIST_H
#define __INCLUDE_LINUX_RCU_SEGCBLIST_H
#include <linux/types.h>
#include <linux/atomic.h>
/* Simple unsegmented callback lists. */
struct rcu_cblist {
struct rcu_head *head;
@ -67,6 +70,7 @@ struct rcu_segcblist {
unsigned long gp_seq[RCU_CBLIST_NSEGS];
long len;
long len_lazy;
u8 enabled;
};
#define RCU_SEGCBLIST_INITIALIZER(n) \