This makes it possible to build pci hotplug drivers outside of the main
kernel tree, and Sam keeps telling me to move local header files to
their proper places...
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 converts drivers/pci to kzalloc usage.
Compile tested with allyes config.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Here's a patch that fixes up the pci_dev refcounting in the CPCI code.
I've done some testing against it and it seems fine here.
Signed-off-by: Scott Murray <scottm@somanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Here is my third attempt at a patch to further update the CompactPCI
hotplug driver infrastructure to address the pci_enable_device issue
discussed on the list as well as a few other issues I discovered during
some more testing. This version addresses a few more issues pointed out
by Prarit Bhargava. Changes include:
- cpci_enable_device and its recursive calling of pci_enable_device on
new devices removed.
- Use list_rwsem to avoid slot status change races between disable_slot
and check_slots.
- Fixed oopsing in cpci_hp_unregister_bus caused by calling list_del on
a slot after calling pci_hp_deregister.
- Removed kfree calls in cleanup_slots since release_slot will have
done it already.
- Reworked init_slots a bit to fix latch and adapter file updating on
subsequent calls to cpci_hp_start.
- Improved sanity checking in cpci_hp_register_controller.
- Now shut things down correctly in cpci_hotplug_exit.
- Switch to pci_get_slot instead of deprecated pci_find_slot.
- A bunch of CodingStyle fixes.
Signed-off-by: Scott Murray <scottm@somanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[PATCH] CPCI: update
I have finally done some work to update the CompactPCI hotplug driver to
fix some of the outstanding issues in 2.6:
- Added adapter and latch status ops so that those files will get created
by the current PCI hotplug core. This used to not be required, but
seems to be now after some of the sysfs rework in the core.
- Replaced slot list spinlock with a r/w semaphore to avoid any potential
issues with sleeping. This quiets all of the runtime warnings.
- Reworked interrupt driven hot extraction handling to remove need for a
polling operator for ENUM# status. There are a lot of boards that only
have an interrupt driven by ENUM#, so this lowers the bar to entry.
- Replaced pci_visit_dev usage with better use of the PCI core functions.
The new code is functionally equivalent to the previous code, but the
use of pci_enable_device on insert needs to be investigated further, as
I need to do some more testing to see if it is still necessary.
Signed-off-by: Scott Murray <scottm@somanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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!
Scott Murray
Greg Kroah-Hartman
David Howells
Thomas Gleixner
Jörn Engel
Eric Sesterhenn
Linus Torvalds