[PATCH] Add better resolution to initcall_debug timings

From: Tim Bird
Date: Fri Sep 12 2008 - 15:48:54 EST

Change the time resolution for initcall_debug to microseconds,
from milliseconds. This is handy to determine which
initcalls you want to work on for faster booting.

One one of my test machines, over 90% of the initcalls are
less than a millisecond and (without this patch) these are
all reported as 0 msecs. Working on the 900 us ones is more
important than the 4 us ones.

With 'quiet' on the kernel command line, this adds no significant
overhead to kernel boot time.

Signed-off-by: Tim Bird <tim.bird@xxxxxxxxxxx>
init/main.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/init/main.c b/init/main.c
index bdc8be0..f441cad 100644
--- a/init/main.c
+++ b/init/main.c
@@ -719,8 +719,8 @@ int do_one_initcall(initcall_t fn)
delta = ktime_sub(t1, t0);

print_fn_descriptor_symbol("initcall %s", fn);
- printk(" returned %d after %Ld msecs\n", result,
- (unsigned long long) delta.tv64 >> 20);
+ printk(" returned %d after %Ld usecs\n", result,
+ (unsigned long long) delta.tv64 >> 10);

msgbuf[0] = 0;

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