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)
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>
Please include the attached patch that adds support for a new PHY to the
sis900 driver. See also Bugzilla 6919.
Signed-off-by: Daniele Venzano <venza@brownhat.org>
--
Signed-off-by: Jeff Garzik <jeff@garzik.org>
661FX7MI-S motherboard which uses the SiS 661FX chipset. The patch adds
an entry to mii_chip_info for the transceiver.
The PHY ids were found using the sis900_c_122.diff patch from
http://brownhat.org/sis900.html but that patch didn't solve the problem,
because the PHY at address 1 was already being chosen.
Without my patch, when bursts of packets arrive from other hosts on a
LAN, the interface dropped one roughly 10% of the time, causing
retransmits. There were fifth second pauses in refresh of large xterms,
and it made Netrek suck. I can provide further test data.
Workaround in lieu of patch is to use mii-tool to advertise
100baseTx-HD, then force renegotiation.
I wasn't able to identify the actual transceiver, so the description
field is a guess.
This patch is similar to Artur Skawina's patch:
http://marc.theaimsgroup.com/?l=linux-netdev&m=114297516729079&w=2
I'm not sure, but I wonder if it means the default behaviour should be
changed, so as to better handle future transceivers.
Diff is against 2.6.16.13.
Signed-off-by: James Cameron <james.cameron@hp.com>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
The attached patch adds support for VLANs to the sis900 driver and bumps
the version number. It is based on an old (2003) patch for the 2.4
series by Hamid Hashemi Golpayegani. It applies on top of 2.6.16(.5).
I have one report that it works and behaves as intended.
Please review and consider for inclusion.
Signed-off-by: Daniele Venzano <venza@brownhat.org>
--
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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>
this patch is required to get a SIS964 based motherboard ethernet working (FSC D1875)
(picking the #1 transceiver, instead of the last one, in case no known ones were found
might be a better default, and would have worked in this case too)
Signed-off-by: Artur Skawina <art_k@o2.pl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix two bugs in the WoL implementation of sis900. The first causes
hangs on some system on driver load, the second causes troubles
when disabling WoL support. Both fixes are one liner and really
simple.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Daniele Venzano <venza@brownhat.org>
Sorry, but that day I had smoked somthing too heavy for me, the patch
didn't apply. Here's a new one.
The patch availble below adds support for Wake on LAN to the sis900
driver. Some register addresses were added to sis900.h and two new
functions were implemented in sis900.c. WoL status is controlled by
ethtool.
Patch is against 2.6.13.
Comments are welcome, but also consider for inclusion in the -mm series.
Signed-off-by: Daniele Venzano <venza@brownhat.org>
--
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
1) Forgotten counter incrementation in sis900_rx() in case
it doesn't get memory for skb, that leads to whole interface failure.
Problem is accompanied with messages:
eth0: Memory squeeze,deferring packet.
eth0: NULL pointer encountered in Rx ring, skipping
2) If counter cur_rx overflows and there'll be temporary memory problems
buffer can't be recreated later, when memory IS available.
3) Limit the work in handler to prevent the endless packets processing
if new packets are generated faster then handled.
Signed-off-by: Konstantin Khorenko <khorenko@sw.ru>
Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Many drivers use skb->tail unnecessarily.
In these situations, the code roughly looks like:
dev = dev_alloc_skb(...);
[optional] skb_reserve(skb, ...);
... skb->tail ...
But even if the skb_reserve() happens, skb->data equals
skb->tail. So it doesn't make any sense to use anything
other than skb->data in these cases.
Another case was the s2io.c driver directly mucking with
the skb->data and skb->tail pointers. It really just wanted
to do an skb_reserve(), so that's what the code was changed
to do instead.
Another reason I'm making this change as it allows some SKB
cleanups I have planned simpler to merge. In those cleanups,
skb->head, skb->tail, and skb->end pointers are removed, and
replaced with skb->head_room and skb->tail_room integers.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Use the DMA_32BIT_MASK constant from dma-mapping.h when calling
pci_set_dma_mask() or pci_set_consistent_dma_mask() instead of custom
macros.
This patch includes dma-mapping.h explicitly because it caused errors
on some architectures otherwise.
See http://marc.theaimsgroup.com/?t=108001993000001&r=1&w=2 for details
Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Add support to sis900 for the following ethtool ops:
- get_link
- get_settings
- set_settings
- nway_reset
Signed-off-by: Daniele Venzano <webvenza@libero.it>
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!
David Howells