Re: [patch] voluntary-preempt-2.6.9-rc1-bk4-Q5

[Ingo Molnar]

* Lee Revell <rlrevell@xxxxxxxxxxx> wrote:

> On Tue, 2004-08-31 at 16:20, Ingo Molnar wrote:
> > so ... could you try the patch below - does it work and how does the
> > latency look like now? (ontop of an unmodified generic.c)
> > 
> 
> Now it looks like this:
> 
> preemption latency trace v1.0.2
> -------------------------------
>  latency: 574 us, entries: 19 (19)
>     -----------------
>     | task: X/1391, uid:0 nice:0 policy:0 rt_prio:0
>     -----------------
>  => started at: cond_resched+0xd/0x40
>  => ended at:   sys_ioctl+0xdf/0x290
> =======>
> 00000001 0.000ms (+0.000ms): touch_preempt_timing (cond_resched)
> 00000001 0.000ms (+0.000ms): do_blank_screen (vt_ioctl)
> 00000001 0.000ms (+0.000ms): is_console_locked (do_blank_screen)
> 00000001 0.001ms (+0.000ms): hide_cursor (do_blank_screen)
> 00000001 0.002ms (+0.000ms): vgacon_cursor (hide_cursor)
> 00000001 0.004ms (+0.001ms): hide_softcursor (do_blank_screen)
> 00000001 0.004ms (+0.000ms): is_console_locked (do_blank_screen)
> 00000001 0.004ms (+0.000ms): vgacon_save_screen (do_blank_screen)
> 00000001 0.005ms (+0.000ms): _mmx_memcpy (vgacon_save_screen)
> 00000001 0.006ms (+0.000ms): kernel_fpu_begin (_mmx_memcpy)
> 00000001 0.481ms (+0.475ms): vgacon_blank (do_blank_screen)
> 00000001 0.481ms (+0.000ms): vgacon_set_origin (vgacon_blank)
> 00000001 0.573ms (+0.091ms): set_origin (vt_ioctl)
> 00000001 0.573ms (+0.000ms): is_console_locked (set_origin)
> 00000001 0.573ms (+0.000ms): vgacon_set_origin (set_origin)
> 00000001 0.574ms (+0.000ms): release_console_sem (vt_ioctl)
> 00000001 0.575ms (+0.000ms): sub_preempt_count (sys_ioctl)
> 00000001 0.575ms (+0.000ms): _mmx_memcpy (check_preempt_timing)
> 00000001 0.575ms (+0.000ms): kernel_fpu_begin (_mmx_memcpy)

hm, this doesnt seem to be an mtrr latency - this is a text-console 
blanking operation apparently running with the BKL enabled.

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