Commit Graph

8 Commits

Author SHA1 Message Date
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00
Takashi Iwai f40b68903c [ALSA] Fix section mismatch errors in ALSA PCI drivers
Fixed 'section mismatch' errors in ALSA PCI drivers:
- removed invalid __devinitdata from pci id tables
- fix/remove __devinit of functions called in suspend/resume

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2006-07-12 20:08:01 +02:00
Dale Sedivec 99e80e4d0c [ALSA] au88x0 - clean up __devinit/__devexit
Modules: au88x0 driver

Removed all use of __devinit/__devexit and init.h from headers.  Any
attributes given in the prototype but not in the function definition have
been moved to the definition.

An exception is vortex_eq_free: I removed the __devexit attribute because
vortex_eq_free is called from vortex_core_shutdown, and
vortex_core_shutdown may be called from __devinit snd_vortex_create.

Compile tested with allyesconfig and allmodconfig.

Signed-off-by: Dale Sedivec <dale@codefu.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2006-04-12 11:34:15 +02:00
Takashi Iwai 97c67b65cb [ALSA] au88x0 - 64bit arch fixes
Modules: au88x0 driver

Fix the driver codes to run on 64bit architectures.
The patch taken from ALSA BTS bug#1047.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2006-03-22 10:23:32 +01:00
Takashi Iwai 2fd16874aa [ALSA] Remove xxx_t typedefs: PCI AU88x0
Modules: au88x0 driver

Remove xxx_t typedefs from the PCI AU88x0 drivers.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2006-01-03 12:18:59 +01:00
Takashi Iwai 99b359ba10 [ALSA] Add missing KERN_* suffix to printk
Add missing KERN_* suffix to printk.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2005-11-04 13:19:23 +01:00
Sasha Khapyorsky f2b31737e5 [ALSA] au88x0: codec access procs for multiple AC97 codecs
Modules: au88x0 driver

This patch extends au88x0 AC97 codec access procedures to handle multiple
codecs properly.

Signed-off-by: Sasha Khapyorsky <sashak@smlink.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2005-11-04 13:16:24 +01:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00