Impact: cleanup, move all hrtimer processing into hardirq context

This is an attempt at removing some of the hrtimer complexity by
reducing the number of callback modes to 1.

This means that all hrtimer callback functions will be ran from HARD-irq
context.

I went through all the 30 odd hrtimer callback functions in the kernel
and saw only one that I'm not quite sure of, which is the one in
net/can/bcm.c - hence I'm CC-ing the folks responsible for that code.

Furthermore, the hrtimer core now calls callbacks directly with IRQs
disabled in case you try to enqueue an expired timer. If this timer is a
periodic timer (which should use hrtimer_forward() to advance its time)
then it might be possible to end up in an inf. recursive loop due to the
fact that hrtimer_forward() doesn't round up to the next timer
granularity, and therefore keeps on calling the callback - obviously
this needs a fix.

Aside from that, this seems to compile and actually boot on my dual core
test box - although I'm sure there are some bugs in, me not hitting any
makes me certain :-)
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Change HRTIMER_CB_IRQSAFE to HRTIMER_CB_SOFTIRQ,
as suggested by Thomas Gleixner.
That solves the lock dependancy reported in
Bug #10701.
That also allows to call hrtimer_start()
directly, tasklet "stupid hack" removed.
Signed-off-by: NStas Sergeev <stsp@aknet.ru>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/drivers/pcsp/pcsp.c: In function 'pcsp_suspend':
sound/drivers/pcsp/pcsp.c:201: error: implicit declaration of function 'snd_pcm_suspend_all'
Signed-off-by: NJohann Felix Soden <johfel@users.sourceforge.net>
CC: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Signed-off-by: NStas Sergeev <stsp@aknet.ru>
(fixed invalid KERN_WARNING by tiwai)
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/drivers/pcsp/pcsp.c: In function 'snd_pcsp_create':
sound/drivers/pcsp/pcsp.c:54: error: 'loops_per_jiffy' undeclared (first use in\ this function)
sound/drivers/pcsp/pcsp.c:54: error: (Each undeclared identifier is reported on\ ly once
sound/drivers/pcsp/pcsp.c:54: error: for each function it appears in.)
Signed-off-by: NMariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

pcsp: locking fix.
Signed-off-by: NStas Sergeev <stsp@aknet.ru>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Simplify init code.
Signed-off-by: NStas Sergeev <stsp@aknet.ru>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

- make pcsp_start_timer_tasklet static
- remove redundant includes. <asm/i8253.h> is not available on all platforms.
Signed-off-by: NStas Sergeev <stsp@aknet.ru>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Added PC-speaker sound driver (snd-pcsp).
Signed-off-by: NStas Sergeev <stsp@aknet.ru>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>