rcu: Convert rcu_gpnum_ovf() to ->gp_seq

This commit converts rcu_gpnum_ovf() to use ->gp_seq instead of ->gpnum.
Same size unsigned long, so same approach.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2018-04-27 18:06:08 -07:00
parent 67e14c1e39
commit a66ae8ae35

View file

@ -1089,14 +1089,15 @@ static int rcu_is_cpu_rrupt_from_idle(void)
/* /*
* We are reporting a quiescent state on behalf of some other CPU, so * We are reporting a quiescent state on behalf of some other CPU, so
* it is our responsibility to check for and handle potential overflow * it is our responsibility to check for and handle potential overflow
* of the rcu_node ->gpnum counter with respect to the rcu_data counters. * of the rcu_node ->gp_seq counter with respect to the rcu_data counters.
* After all, the CPU might be in deep idle state, and thus executing no * After all, the CPU might be in deep idle state, and thus executing no
* code whatsoever. * code whatsoever.
*/ */
static void rcu_gpnum_ovf(struct rcu_node *rnp, struct rcu_data *rdp) static void rcu_gpnum_ovf(struct rcu_node *rnp, struct rcu_data *rdp)
{ {
raw_lockdep_assert_held_rcu_node(rnp); raw_lockdep_assert_held_rcu_node(rnp);
if (ULONG_CMP_LT(READ_ONCE(rdp->gpnum) + ULONG_MAX / 4, rnp->gpnum)) if (ULONG_CMP_LT(rcu_seq_current(&rdp->gp_seq) + ULONG_MAX / 4,
rnp->gp_seq))
WRITE_ONCE(rdp->gpwrap, true); WRITE_ONCE(rdp->gpwrap, true);
if (ULONG_CMP_LT(rdp->rcu_iw_gpnum + ULONG_MAX / 4, rnp->gpnum)) if (ULONG_CMP_LT(rdp->rcu_iw_gpnum + ULONG_MAX / 4, rnp->gpnum))
rdp->rcu_iw_gpnum = rnp->gpnum + ULONG_MAX / 4; rdp->rcu_iw_gpnum = rnp->gpnum + ULONG_MAX / 4;