[17/41] init: use ktime_us_delta() to make initcall_debug log more precise

Commit Message

Andrew Morton March 23, 2022, 11:06 p.m. UTC

From: Mark-PK Tsai <[e-mail]>
Subject: init: use ktime_us_delta() to make initcall_debug log more precise

Use ktime_us_delta() to make the initcall_debug log more precise than
right shifting the result of ktime_to_ns() by 10 bits.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Mark-PK Tsai <[e-mail]>
Reviewed-by: Andrew Halaney <[e-mail]>
Tested-by: Andrew Halaney <[e-mail]>
Cc: Steven Rostedt <[e-mail]>
Cc: Matthias Brugger <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Cc: Kefeng Wang <[e-mail]>
Cc: Rasmus Villemoes <[e-mail]>
Cc: Kees Cook <[e-mail]>
Cc: Valentin Schneider <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: YJ Chiang <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 init/main.c |    8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

Patch

--- a/init/main.c~init-use-ktime_us_delta-to-make-initcall_debug-log-more-precise
+++ a/init/main.c
@@ -1246,15 +1246,11 @@  trace_initcall_start_cb(void *data, init
 static __init_or_module void
 trace_initcall_finish_cb(void *data, initcall_t fn, int ret)
 {
-	ktime_t *calltime = (ktime_t *)data;
-	ktime_t delta, rettime;
-	unsigned long long duration;
+	ktime_t rettime, *calltime = (ktime_t *)data;
 
 	rettime = ktime_get();
-	delta = ktime_sub(rettime, *calltime);
-	duration = (unsigned long long) ktime_to_ns(delta) >> 10;
 	printk(KERN_DEBUG "initcall %pS returned %d after %lld usecs\n",
-		 fn, ret, duration);
+		 fn, ret, (unsigned long long)ktime_us_delta(rettime, *calltime));
 }
 
 static ktime_t initcall_calltime;