RFC new human-time soft-timer subsystem
Get series with b4
b4 am [email protected]Versions newest first
- v1 RFC Latest4 patches 6 repliesIn review
Patches in v1 No applies recorded yet
| # | Subject and files | Size | Replies | Applied |
|---|---|---|---|---|
| 1/4 | add jiffies_to_nsecs() helper and fix up size of usecsinclude/ | +13 | 4 replies | |
| 2/4 | human-time soft-timer core changesinclude/ include/ kernel/ +1 more | +220 | 0 replies | |
| 2/4 | human-time soft-timer core changesinclude/ include/ kernel/ +1 more | +157 | 0 replies | |
| 3/4 | new human-time schedule_timeout() functionsinclude/ include/ kernel/ | +158 | 0 replies | |
| 4/4 | convert sys_nanosleep() to use set_timer_nsecs()include/ kernel/ | +45 | 0 replies |
Reviews trailers per patch
No Reviewed-by, Acked-by or Tested-by trailers for v1 yet.
Cover letter [RFC][PATCH 0/4] new human-time soft-timer subsystem
On 14.07.2005 [12:18:41 -0700], john stultz wrote:
<snip>
Quoted 5 lines
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