From 489832609a1ad7189d11715d8cefb457d90182c5 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 24 Sep 2012 16:08:31 -0700 Subject: [PATCH] rcu: Make rcutorture give diagnostics if CPU offline fails This commit causes rcutorture to print the errno if cpu_down() fails when the rcutorture "verbose" module parameter is specified. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index aaa7b9f3532..9900f560f1b 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1502,6 +1502,7 @@ rcu_torture_onoff(void *arg) unsigned long delta; int maxcpu = -1; DEFINE_RCU_RANDOM(rand); + int ret; unsigned long starttime; VERBOSE_PRINTK_STRING("rcu_torture_onoff task started"); @@ -1522,7 +1523,13 @@ rcu_torture_onoff(void *arg) torture_type, cpu); starttime = jiffies; n_offline_attempts++; - if (cpu_down(cpu) == 0) { + ret = cpu_down(cpu); + if (ret) { + if (verbose) + pr_alert("%s" TORTURE_FLAG + "rcu_torture_onoff task: offline %d failed: errno %d\n", + torture_type, cpu, ret); + } else { if (verbose) pr_alert("%s" TORTURE_FLAG "rcu_torture_onoff task: offlined %d\n",