srcu: Make rcutorture dump the SRCU size state

This commit adds the numeric and string version of ->srcu_size_state to
the Tree-SRCU-specific portion of the rcutorture output.

[ paulmck: Apply feedback from kernel test robot and Dan Carpenter. ]
[ quic_neeraju: Apply feedback from Jiapeng Chong. ]

Co-developed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 00f9aed..0874e3b 100644 (file)
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -1407,15 +1407,33 @@ void srcutorture_get_gp_data(enum rcutorture_type test_type,
 }
 EXPORT_SYMBOL_GPL(srcutorture_get_gp_data);
 
+static const char * const srcu_size_state_name[] = {
+       "SRCU_SIZE_SMALL",
+       "SRCU_SIZE_ALLOC",
+       "SRCU_SIZE_WAIT_BARRIER",
+       "SRCU_SIZE_WAIT_CALL",
+       "SRCU_SIZE_WAIT_CBS1",
+       "SRCU_SIZE_WAIT_CBS2",
+       "SRCU_SIZE_WAIT_CBS3",
+       "SRCU_SIZE_WAIT_CBS4",
+       "SRCU_SIZE_BIG",
+       "SRCU_SIZE_???",
+};
+
 void srcu_torture_stats_print(struct srcu_struct *ssp, char *tt, char *tf)
 {
        int cpu;
        int idx;
        unsigned long s0 = 0, s1 = 0;
+       int ss_state = READ_ONCE(ssp->srcu_size_state);
+       int ss_state_idx = ss_state;
 
        idx = ssp->srcu_idx & 0x1;
-       pr_alert("%s%s Tree SRCU g%ld per-CPU(idx=%d):",
-                tt, tf, rcu_seq_current(&ssp->srcu_gp_seq), idx);
+       if (ss_state < 0 || ss_state >= ARRAY_SIZE(srcu_size_state_name))
+               ss_state_idx = ARRAY_SIZE(srcu_size_state_name) - 1;
+       pr_alert("%s%s Tree SRCU g%ld state %d (%s) per-CPU(idx=%d):",
+                tt, tf, rcu_seq_current(&ssp->srcu_gp_seq), ss_state,
+                srcu_size_state_name[ss_state_idx], idx);
        for_each_possible_cpu(cpu) {
                unsigned long l0, l1;
                unsigned long u0, u1;