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)
Received from Mark Salyzyn:
The only real difference between the rkt and rx platform modules is the
offset of the message registers. This patch recognizes this similarity
and simplifies the driver to reduce it's code footprint and to improve
maintainability by reducing the code duplication.
Visibly, the 'rkt.c' portion of this patch looks more complicated than
it really is. View it as retaining the rkt-only specifics of the
interface.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Received From Mark Salyzyn
A race condition existed that could result in a lost completion of a
command to the ppc based cards.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Received From Mark Salyzyn
Add the ability to adjust for unusual corner case failures. Both of
these additional module parameters deal with embedded, non-intel or
complicated system scenarios.
Aif_timeout can be increased past the default 2 minute timeout to drop
application registrations when a system has an unusually high event load
resulting from continuing management requests, or simultaneous builds,
or sluggish user space as a result of system load.
Startup_timeout can be increased past the default 3 minute timeout to
drop an adapter initialization for systems that have a very large number
of targets, or slow to spin-up targets, or a complicated set of array
configurations that extend the time for the firmware to declare that it
is operational. This timeout would only have an affect on non-intel
based systems, as the (more patient) BIOS would generally be where the
startup delay would be dealt with.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Received from Mark Salyzyn
Remove superfluous code, optimize code, harden code, cast code, correct
some text, use msleep instead of schedule_timeout_interruptible. No
bugs.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Use schedule_timeout_uninterruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Received from Mark Salyzyn.
This patch adds the 'new comm' interface, which modern AAC based
adapters that are less than a year old support in the name of much
improved performance. These modern adapters support both the legacy and
the 'new comm' interfaces.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Add in pci shutdown method so that the adapter shuts down correctly and
flushes its cache. Shutdown should also disable the adapter's interrupt
when shutdown (in particularly if the driver is rmmod'd) to prevent
spurious hardware activities.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
New code from the Adaptec driver. Performance enhancement for newer
adapters. I hope that this isn't too big for a single patch. I believe
that other than the few small cleanups mentioned, that the changes are
all related.
- Added Variable FIB size negotiation for new adapters.
- Added support to maximize scatter gather tables and thus permit
requests larger than 64KB/each.
- Limit Scatter Gather to 34 elements for ROMB platforms.
- aac_printf is only enabled with AAC_QUIRK_34SG
- Large FIB ioctl support
- some minor cleanup
Passes sparse check.
I have tested it on x86 and ppc64 machines.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch addresses the sparse -Wbitwise warnings that Christoph wanted
me to eliminate. This mostly consisted of making data structure
elements of hardware associated structures the __le* equivalent.
Although there were a couple places where there was mixing of cpu and le
variable math. These changes have been tested on both an x86 and ppc
machine running bonnie++. The usage of the LE32_ALL_ONES macro has been
eliminated.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch makes some needlessly global functions static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.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