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)
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>
convert au1000_eth driver to use PHY framework and garbage collected
functions and identifiers that became unused/obsolete in the process
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
since the au1000 driver already selects the CRC32 routines, simply replace
the internal ether_crc() implementation with the semantically equivalent
one from <linux/crc32.h>
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Straighten up the AMD Au1xx0 Ethernet probing code, make it print out (and
store in the 'net_device' structure) the physical address of the controller,
not the KSEG1-based virtual. Make the driver also claim/release the 4-byte MAC
enable registers and assign to the Ethernet ports two consecutive MAC
addresses to match those that are printed on their stickers.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
With Au1xx0 Ethernet driver, TX bytes/packets always remain zero. The
problem seems to be that when packet has been transmitted, the length word
in DMA buffer is zero.
The patch updates the TX stats when a buffer is fed to DMA. The initial
2.4 patch was posted to linux-mips@linux-mips.org by Thomas Lange 21 Jan
2005.
Signed-off-by: Thomas Lange <thomas@corelatus.se>
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
o Add support for DP83847 MII.
o remove unused variable.
o Add some initialisations so even an unknown MII won't result in a crash.
o Correct error message to "no known MIIs found".
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
drivers/net/au1000_eth.c | 13 +++++--------
1 files changed, 5 insertions(+), 8 deletions(-)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
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!
Ralf Baechle