lkml.org 
[lkml]   [2005]   [Jul]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subject[RFC][PATCH 0/4] new human-time soft-timer subsystem
On 14.07.2005 [12:18:41 -0700], john stultz wrote:

<snip>

> Nish has some code, which I hope he'll be sending out shortly that
> does just this, converting the soft-timer subsystem to use absolute
> time instead of ticks for expiration. I feel it both simplifies the
> code and makes it easier to changing the timer interrupt frequency
> while the system is running.

Here's the set of patches John promised :)

1/4: add jiffies conversion helper functions

2/4: core human-time modifications to soft-timer subsystem

3/4: add new human-time schedule_timeout() functions

4/4: rework sys_nanosleep() to use schedule_timeout_nsecs()

The individual patches have more details, but the gist is this:

We no longer use jiffies (the variable) as the basis for determining
what "time" a timer should expire or when it should be added. Instead,
we use a new function, do_monotonic_clock(), which is simply a wrapper
for getnstimeofday(). That is to say, we use uptime in nanoseconds. But,
to avoid modifying the existing soft-timer algorithm, we convert the
64-bit nanosecond value to "timerinterval" units. These units are simply
2^TIMEINTERVAL_BITS nanoseconds in length (thus determined at compile
time).

To sum up, soft-timers now use time (as defined by the
timeofday-subsystem) not ticks. Hopefully, the individual
e-mails/patches make this change clear.

Thanks,
Nish
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-07-14 22:58    [W:0.084 / U:7.520 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site