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)
This patch removes the dependency on ieee80211.h from
the ray_cs driver. ray_cs only needs iw_handler.h.
Signed-off-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
First of all it is unnecessary to allocate a new skb in skb_pad since
the existing one is not shared. More importantly, our hard_start_xmit
interface does not allow a new skb to be allocated since that breaks
requeueing.
This patch uses pskb_expand_head to expand the existing skb and linearize
it if needed. Actually, someone should sift through every instance of
skb_pad on a non-linear skb as they do not fit the reasons why this was
originally created.
Incidentally, this fixes a minor bug when the skb is cloned (tcpdump,
TCP, etc.). As it is skb_pad will simply write over a cloned skb. Because
of the position of the write it is unlikely to cause problems but still
it's best if we don't do it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of the two status values struct pcmcia_device->p_state and state,
use descriptive bitfields. Most value-checking in drivers was invalid, as
the core now only calls the ->remove() (a.k.a. detach) function in case the
attachement _and_ configuration was successful.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Remove the unused DEV_RELEASE_PENDING flag, and move the DEV_SUSPEND flag
into the p_dev structure, and make use of it at the core level.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Most of the driver initialization isn't done in the .probe function, but in
the internal _config() functions. Make them return a value, so that .probe
can properly report whether the probing of the device succeeded or not.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
dev_link_t * and client_handle_t both mean struct pcmcai_device * by now.
Therefore, remove all such indirections.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Embed dev_link_t into struct pcmcia_device(), as they basically address the
same entity. The actual contents of dev_link_t will be cleaned up step by step.
This patch includes a bugfix from and signed-off-by Andrew Morton.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As we do not allow setting Vcc in the pcmcia core, and Vpp1 and
Vpp2 can only be set to the same value, a lot of code can be
streamlined.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
In all but one case, the suspend and resume functions of PCMCIA drivers
contain mostly of calls to pcmcia_release_configuration() and
pcmcia_request_configuration(). Therefore, move this code out of the
drivers and into the core.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Convert the remaining drivers which use pcmcia_release_io or
pcmcia_release_irq, and remove the EXPORT of these symbols.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
ESSIDs can technically include NULL characters. Drivers should not be
adjusting the length of the ESSID before reporting it in their
SIOCGIWESSID handlers. Breaks stuff like wpa_supplicant. Note that ipw
drivers, which seem to currently be the "most correct", don't have this
problem.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Unify the EVENT_CARD_INSERTION and "attach" callbacks to one unified
probe() callback. As all in-kernel drivers are changed to this new
callback, there will be no temporary backwards-compatibility. Inside a
probe() function, each driver _must_ set struct pcmcia_device
*p_dev->instance and instance->handle correctly.
With these patches, the basic driver interface for 16-bit PCMCIA drivers
now has the classic four callbacks known also from other buses:
int (*probe) (struct pcmcia_device *dev);
void (*remove) (struct pcmcia_device *dev);
int (*suspend) (struct pcmcia_device *dev);
int (*resume) (struct pcmcia_device *dev);
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Unify the "detach" and REMOVAL_EVENT handlers to one "remove" function.
Old functionality is preserved, for the moment.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Move the suspend and resume methods out of the event handler, and into
special functions. Also use these functions for pre- and post-reset, as
almost all drivers already do, and the remaining ones can easily be
converted.
Bugfix to include/pcmcia/ds.c
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
This adds support for WE-17 to the ray_cs driver. Tested
with 2.6.13 (with real HW).
Signed-off-by: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
As a follow-up, remove the inclusion of pcmcia/version.h in many files.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move the "event handler" to struct pcmcia_driver -- the unified event handler
will disappear really soon, but switching it to struct pcmcia_driver in the
meantime allows for better "step-by-step" patches.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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!
