From 6b50e119c440b7532ed749b635a58b3839f62992 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 17 Nov 2015 14:39:26 -0800 Subject: [PATCH] rcutorture: 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: Updated to fix relational operator called out by Dan Carpenter. ] [ paulmck: More "const", as suggested by Josh Triplett. ] Reviewed-by: Josh Triplett --- kernel/rcu/tree.c | 15 +++++++++++++-- kernel/rcu/tree.h | 12 ++++++++++++ 2 files changed, 25 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 7b78c88e19a3..316354109734 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1186,6 +1186,16 @@ static void record_gp_stall_check_time(struct rcu_state *rsp) rsp->n_force_qs_gpstart = READ_ONCE(rsp->n_force_qs); } +/* + * Convert a ->gp_state value to a character string. + */ +static const 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. */ @@ -1197,10 +1207,11 @@ 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 f32bebb6bc90..a3fb6fe94127 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -545,6 +545,18 @@ struct rcu_state { #define RCU_GP_CLEANUP 5 /* Grace-period cleanup started. */ #define RCU_GP_CLEANED 6 /* Grace-period cleanup complete. */ +#ifndef RCU_TREE_NONCORE +static const 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", +}; +#endif /* #ifndef RCU_TREE_NONCORE */ + extern struct list_head rcu_struct_flavors; /* Sequence through rcu_state structures for each RCU flavor. */