Re: [PATCH]drivers:base:power:trace.c Add "UTC" Coordinated UniversalTime to the printk.

From: Justin P. Mattock
Date: Sun Jun 19 2011 - 02:40:24 EST

On 06/14/2011 01:02 PM, Rafael J. Wysocki wrote:
On Tuesday, June 14, 2011, Justin P. Mattock wrote:
On 06/13/2011 02:47 PM, Rafael J. Wysocki wrote:
On Monday, June 13, 2011, Justin P. Mattock wrote:
On 06/12/2011 01:27 PM, Rafael J. Wysocki wrote:
On Sunday, June 12, 2011, Justin P. Mattock wrote:
On 06/12/2011 11:35 AM, Rafael J. Wysocki wrote:
On Sunday, June 12, 2011, Justin P. Mattock wrote:
On 06/12/2011 05:12 AM, Rafael J. Wysocki wrote:

On Thursday, June 09, 2011, Justin P. Mattock wrote:
From: "Justin P. Mattock"<justinmattock@xxxxxxxxx>

sounds stupid, but taking a glance at the time, and seeing the wrong time, or what seemed
wrong in dmesg, caused me to go into total check the time clock panic mode.. So the patch below adds:
"UTC" Coordinated Universal Time abreviation to the printk so people like me dont flip out over the time!

[ 0.114915] Time: 1:47:03 Date: 06/09/11

[ 0.114728] Time: 5:46:02 UTC Date: 06/09/11

Signed-off-by: Justin P. Mattock<justinmattock@xxxxxxxxx>

I suspect the goal is to mark messages printed by the PM trace code so that
they can be easily distinguished from messages from other sources to avoid
confusion. Why do you think it's a good idea to use the "UTC" string for
this purpose? The time printed in those messages need not be UTC.

It would be better to simply print "RTC time: ..., date: ..." IMO.


well.. if thats better, then thats better.. over here(people that dont
know what RTC time is) would not get so confused with a simple UTC or
PDT or whatever the time zone is but if RTC is bettr, then its better.

My point is we don't know this time is always UTC, so we rather shouldn't
label it as UTC unconditionally, should we?


sounds good to me!!

I'm not sure what you mean?

with what you are saying "RTC" if anything.. rather than "UTC"

So, it looks like you'd like the appended patch to be appiled?


whatever works best with you guys...

OK, I'll queue up the one below for 3.1, then.

before anything happens, I just noticed down dmesg:

[ 1.931771] Magic number: 15:676:165
[ 1.940022] rtc_cmos 00:08: setting system clock to 2011-06-19 06:11:22 UTC (1308463882)
[ 1.948456] Initializing network drop monitor service

see how there is a UTC after the time. should this be for the above?
(keep in mind I just noticed this, so I could be wrong)

I just tripped out on that, and created what I had sent out..

From: Rafael J. Wysocki<rjw@xxxxxxx>
Subject: PM: Add "RTC" to PM trace time stamps to avoid confusion

Some users are apparently confused by dmesg output from
read_magic_time(), which looks like "real" time and date.
Add the "RTC" string to time stamps printed by read_magic_time() to
avoid that confusion.

Reported-by: Justin P. Mattock<justinmattock@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki<rjw@xxxxxxx>
drivers/base/power/trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6/drivers/base/power/trace.c
--- linux-2.6.orig/drivers/base/power/trace.c
+++ linux-2.6/drivers/base/power/trace.c
@@ -112,7 +112,7 @@ static unsigned int read_magic_time(void
unsigned int val;

- pr_info("Time: %2d:%02d:%02d Date: %02d/%02d/%02d\n",
+ pr_info("RTC time: %2d:%02d:%02d, date: %02d/%02d/%02d\n",
time.tm_hour, time.tm_min, time.tm_sec,
time.tm_mon + 1, time.tm_mday, time.tm_year % 100);
val = time.tm_year; /* 100 years */

Justin P. Mattock

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