cpu: Better output when waiting for a very long job

Instead of printing at the end if the job took more than 1s,
print in the loop every 30s along with a backtrace. This will
give us some output if the job is deadlocked.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[stewart: bump to 30s rather than 5s, preserve PR_DEBUG for >1s]
Signed-off-by: Stewart Smith <stewart@linux.ibm.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/core/cpu.c b/core/cpu.c
index c6a1bf9..88477f8 100644
--- a/core/cpu.c
+++ b/core/cpu.c
@@ -300,6 +300,11 @@ void cpu_wait_job(struct cpu_job *job, bool free_it)
 		time_wait_ms(10);
 		time_waited += 10;
 		lwsync();
+		if ((time_waited % 30000) == 0) {
+			prlog(PR_INFO, "cpu_wait_job(%s) for %lums\n",
+			      job->name, time_waited);
+			backtrace();
+		}
 	}
 	lwsync();