EXP qspinlock: Dump full qnode structure
This commit dumps the full qnode structure, which allows non-standard
queue shapes to be seen.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index 95f3fd7..e07848b 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -688,6 +688,27 @@ static struct mcs_spinlock *next_to_prev(struct mcs_spinlock *msp, int *cpup, in
return NULL;
}
+static struct mcs_spinlock *next_to_cpu_idx(struct mcs_spinlock *msp, int *cpup, int *idxp)
+{
+ int cpu;
+ int idx;
+
+ for_each_possible_cpu(cpu) {
+ struct qnode *qnp = per_cpu_ptr(&qnodes[0], cpu);
+
+ for (idx = 0; idx < MAX_NODES; idx++) {
+ if (&qnp[idx].mcs == msp) {
+ *cpup = cpu;
+ *idxp = idx;
+ return &qnp[idx].mcs;
+ }
+ }
+ }
+ *cpup = -1;
+ *idxp = -1;
+ return NULL;
+}
+
void spinlock_dump(spinlock_t *sp, bool full)
{
int cpu;
@@ -718,6 +739,23 @@ void spinlock_dump(spinlock_t *sp, bool full)
pr_alert("%s: Queue output truncated.\n", __func__);
else
pr_alert("%s: End of queue.\n", __func__);
+ pr_alert("%s: Full qnodes dump:\n", __func__);
+ for_each_possible_cpu(cpu) {
+ int cpu_next;
+ int idx_next;
+ struct qnode *qnp = per_cpu_ptr(&qnodes[0], cpu);
+
+ pr_alert("\t CPU %d", cpu);
+ for (idx = 0; idx < MAX_NODES; idx++) {
+ if (!qnp[idx].mcs.next) {
+ pr_cont(" --[--]");
+ continue;
+ }
+ msp = next_to_cpu_idx(qnp[idx].mcs.next, &cpu_next, &idx_next);
+ pr_cont(" %2d[%02d]", cpu_next, idx_next);
+ }
+ pr_cont("\n");
+ }
}
EXPORT_SYMBOL(spinlock_dump);
