On Thu, Nov 19, 2015 at 10:34:09PM +0300, Dan Carpenter wrote: > It should be >= ARRAY_SIZE() instead of > ARRAY_SIZE(). > > Fixes: 6231da675578 ('rcu: Print symbolic name for ->gp_state') > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Good catch! I folded this into the original commit with attribution, please see below. Thanx, Paul > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index 6a5e1c4..6559b3c 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -1203,7 +1203,7 @@ static void record_gp_stall_check_time(struct rcu_state *rsp) > */ > static char *gp_state_getname(short gs) > { > - if (gs < 0 || gs > ARRAY_SIZE(gp_state_names)) > + if (gs < 0 || gs >= ARRAY_SIZE(gp_state_names)) > return "???"; > return gp_state_names[gs]; > } ------------------------------------------------------------------------ commit 31bf937d2dcbe71a329e5bc6c7726f3a5949089a Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Date: Tue Nov 17 14:39:26 2015 -0800 rcu: Print symbolic name for ->gp_state Currently, ->gp_state is printed as an integer, which slows debugging. This commit therefore prints a symbolic name in addition to the integer. Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> [ Updated to fix relational operator called out by Daniel Carpenter. ] diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index e768fc64583f..6559b3cb5ea6 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1199,6 +1199,16 @@ static void record_gp_stall_check_time(struct rcu_state *rsp) } /* + * Convert a ->gp_state value to a character string. + */ +static char *gp_state_getname(short gs) +{ + if (gs < 0 || gs >= ARRAY_SIZE(gp_state_names)) + return "???"; + return gp_state_names[gs]; +} + +/* * Complain about starvation of grace-period kthread. */ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp) @@ -1209,10 +1219,11 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp) j = jiffies; gpa = READ_ONCE(rsp->gp_activity); if (j - gpa > 2 * HZ) { - pr_err("%s kthread starved for %ld jiffies! g%lu c%lu f%#x s%d ->state=%#lx\n", + pr_err("%s kthread starved for %ld jiffies! g%lu c%lu f%#x %s(%d) ->state=%#lx\n", rsp->name, j - gpa, rsp->gpnum, rsp->completed, - rsp->gp_flags, rsp->gp_state, + rsp->gp_flags, + gp_state_getname(rsp->gp_state), rsp->gp_state, rsp->gp_kthread ? rsp->gp_kthread->state : ~0); if (rsp->gp_kthread) sched_show_task(rsp->gp_kthread); diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 6cbec31f99d6..5c70b09a85d4 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -546,6 +546,15 @@ struct rcu_state { #define RCU_GP_DOING_FQS 4 /* Wait done for force-quiescent-state time. */ #define RCU_GP_CLEANUP 5 /* Grace-period cleanup started. */ #define RCU_GP_CLEANED 6 /* Grace-period cleanup complete. */ +static char * const gp_state_names[] = { + "RCU_GP_IDLE", + "RCU_GP_WAIT_GPS", + "RCU_GP_DONE_GPS", + "RCU_GP_WAIT_FQS", + "RCU_GP_DOING_FQS", + "RCU_GP_CLEANUP", + "RCU_GP_CLEANED", +}; extern struct list_head rcu_struct_flavors; -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html