Commit Graph

13 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
Jeff Garzik 7282d491ec drivers/net: const-ify ethtool_ops declarations
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-09-13 14:30:00 -04:00
Jeff Garzik 6aa20a2235 drivers/net: Trim trailing whitespace
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-09-13 13:24:59 -04:00
Jeff Garzik 4e83b7fad8 Merge branch 'tmp' into upstream 2006-09-12 11:45:33 -04:00
Andy Gospodarek d5b20697ca [PATCH] Remove more unnecessary driver printk's
As I promised last week, here is the first pass at removing all
unnecessary printk's that exist in network device drivers currently in
promiscuous mode.  The duplicate messages are not needed so they have
been removed.  Some of these drivers are quite old and might not need an
update, but I did them all anyway.

I am currently auditing the remaining conditional printk's and will send
out a patch for those soon.

Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-09-12 11:45:19 -04:00
Jeff Garzik 299176206b drivers/net: Remove deprecated use of pci_module_init()
From: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>

Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2006-08-19 17:48:59 -04:00
Thomas Gleixner 1fb9df5d30 [PATCH] irq-flags: drivers/net: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:51 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Jeff Garzik b2795f5969 [git] change permissions on drivers/net/amd8111e.[ch] to 0644,
removing executable bits.
2005-10-28 16:43:40 -04:00
Olaf Hering 44456d37b5 [PATCH] turn many #if $undefined_string into #ifdef $undefined_string
turn many #if $undefined_string into #ifdef $undefined_string to fix some
warnings after -Wno-def was added to global CFLAGS

Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:08 -07:00
Tobias Klauser cac8c81a59 [PATCH] Use pci_set_dma_mask() instead of direct assignment of DMA mask
The amd8111e driver directly assigns the DMA mask to the dma_mask
member of the struct pci_dev instead of using pci_set_dma_mask(). This
makes the call to pci_dma_supported() redundant as pci_set_dma_mask()
does this check.

I do not own this device so I only compile-tested this patch.

Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
2005-06-27 23:09:08 -04:00
Liu Tao dfa1b73ffb [PATCH] drivers/net/amd8111e.c: fix NAPI interrupt in poll
This patch makes the netif_rx_complete() and rx_interrupt_enable
  atomic when exiting the poll() method, so to avoid interrupt in poll.
  It also fixes the rx interrupt check logic in interrupt handler.
  
  Signed-off-by: Liu Tao <liutao1980@gmail.com>
  Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
2005-05-12 19:40:38 -04:00
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