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)
Fix a lot of typos. Eyeballed by jmc@ in OpenBSD.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Modules: RME9652 driver
This patch fixes off-by-one errors found by the Coverity checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: RME9652 driver
sound/pci/rme9652/hdspm.c: In function 'snd_hdspm_preallocate_memory':
sound/pci/rme9652/hdspm.c:3327: warning: int format, different type arg (arg 4)
sound/pci/rme9652/hdspm.c:3331: warning: int format, different type arg (arg 4)
sound/pci/rme9652/hdspm.c: In function 'snd_hdspm_create':
sound/pci/rme9652/hdspm.c:3513: warning: int format, different type arg (arg 4)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: AD1889 driver,RME9652 driver
This is the sound/ part of the big kfree cleanup patch.
Remove pointless checks for NULL prior to calling kfree() in sound/.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Memalloc module,PCM Midlevel,Timer Midlevel,GUS Library,AC97 Codec
ALI5451 driver,RME9652 driver
Make some functions/variables that are used in only one file static.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Documentation,CS46xx driver,EMU10K1/EMU10K2 driver,AD1848 driver
SB16/AWE driver,CMIPCI driver,ENS1370/1+ driver,RME32 driver
RME96 driver,ICE1712 driver,ICE1724 driver,KORG1212 driver
RME HDSP driver,RME9652 driver
This patch changes .iface to SNDRV_CTL_ELEM_IFACE_MIXER whre _PCM or
_HWDEP was used in controls that are not associated with a specific PCM
(sub)stream or hwdep device, and changes some controls that got
inconsitent .iface values due to copy+paste errors. Furthermore, it
makes sure that all control that do use _PCM or _HWDEP use the correct
number in the .device field.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
