From: Paul E. McKenney <paulmck@kernel.org>
Date: Fri, 2 Aug 2024 00:43:04 +0000 (-0700)
Subject: rcuscale: Make all writer tasks report upon hang
X-Git-Tag: v6.12-rc1~166^2^6~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=abaf1322adbfd4faa28072fd5412e54b9722e477;p=thirdparty%2Fkernel%2Flinux.git

rcuscale: Make all writer tasks report upon hang

This commit causes all writer tasks to provide a brief report after a
hang has been reported, spaced at one-second intervals.

Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
---

diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index 79e1c32d5c0fa..dfe8e0faa4d86 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -483,6 +483,7 @@ rcu_scale_writer(void *arg)
 	unsigned long jdone;
 	long me = (long)arg;
 	struct rcu_head *rhp = NULL;
+	bool selfreport = false;
 	bool started = false, done = false, alldone = false;
 	u64 t;
 	DEFINE_TORTURE_RANDOM(tr);
@@ -593,6 +594,11 @@ retry:
 					cur_ops->stats();
 			}
 		}
+		if (!selfreport && time_after(jiffies, jdone + HZ * (70 + me))) {
+			pr_info("%s: Writer %ld self-report: started %d done %d/%d->%d i %d jdone %lu.\n",
+				__func__, me, started, done, writer_done[me], atomic_read(&n_rcu_scale_writer_finished), i, jiffies - jdone);
+			selfreport = true;
+		}
 		if (started && !alldone && i < MAX_MEAS - 1)
 			i++;
 		rcu_scale_wait_shutdown();