From: Paul E. McKenney <paulmck@kernel.org>
Date: Thu, 5 Dec 2024 22:41:55 +0000 (-0800)
Subject: rcutorture: Add ftrace-compatible timestamp to GP# failure/close-call output
X-Git-Tag: v6.15-rc1~221^2^5~5
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65e6ff0f31184bd9ce01c7bfef28558e6b70f96a;p=thirdparty%2Flinux.git

rcutorture: Add ftrace-compatible timestamp to GP# failure/close-call output

This commit adds an ftrace-compatible microsecond-scale timestamp
to the failure/close-call output, but only in kernels built with
CONFIG_RCU_TORTURE_TEST_LOG_GP=y.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
---

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index fb1b80498ae01..1fdadc1df9adb 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -275,6 +275,7 @@ struct rt_read_seg {
 	int rt_end_cpu;
 	unsigned long long rt_gp_seq;
 	unsigned long long rt_gp_seq_end;
+	u64 rt_ts;
 };
 static int err_segs_recorded;
 static struct rt_read_seg err_segs[RCUTORTURE_RDR_MAX_SEGS];
@@ -1989,6 +1990,7 @@ static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
 	// Sample grace-period sequence number, as good a place as any.
 	if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_LOG_GP) && cur_ops->gather_gp_seqs) {
 		rtrsp->rt_gp_seq = cur_ops->gather_gp_seqs();
+		rtrsp->rt_ts = ktime_get_mono_fast_ns();
 		if (!first)
 			rtrsp[-1].rt_gp_seq_end = rtrsp->rt_gp_seq;
 	}
@@ -3663,7 +3665,11 @@ rcu_torture_cleanup(void)
 			pr_alert("\t: No segments recorded!!!\n");
 		firsttime = 1;
 		for (i = 0; i < rt_read_nsegs; i++) {
-			pr_alert("\t%d: %#4x", i, err_segs[i].rt_readstate);
+			if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_LOG_GP))
+				pr_alert("\t%lluus ", div64_u64(err_segs[i].rt_ts, 1000ULL));
+			else
+				pr_alert("\t");
+			pr_cont("%d: %#4x", i, err_segs[i].rt_readstate);
 			if (err_segs[i].rt_delay_jiffies != 0) {
 				pr_cont("%s%ldjiffies", firsttime ? "" : "+",
 					err_segs[i].rt_delay_jiffies);