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)
Pass ticks to do_timer() and update_times(), and adjust x86_64 and s390
timer interrupt handler with this change.
Currently update_times() calculates ticks by "jiffies - wall_jiffies", but
callers of do_timer() should know how many ticks to update. Passing ticks
get rid of this redundant calculation. Also there are another redundancy
pointed out by Martin Schwidefsky.
This cleanup make a barrier added by
5aee405c66 needless. So this patch removes
it.
As a bonus, this cleanup make wall_jiffies can be removed easily, since now
wall_jiffies is always synced with jiffies. (This patch does not really
remove wall_jiffies. It would be another cleanup patch)
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Hirokazu Takata <takata.hirokazu@renesas.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drivers/built-in.o: In function `sgivwfb_set_par':
sgivwfb.c:(.text+0x88583): undefined reference to `sgivwfb_mem_phys'
sgivwfb.c:(.text+0x88596): undefined reference to `sgivwfb_mem_phys'
sgivwfb.c:(.text+0x885a8): undefined reference to `sgivwfb_mem_phys'
drivers/built-in.o: In function `sgivwfb_check_var':
sgivwfb.c:(.text+0x88ad0): undefined reference to `sgivwfb_mem_size'
drivers/built-in.o: In function `sgivwfb_mmap':
sgivwfb.c:(.text+0x88c75): undefined reference to `sgivwfb_mem_size'
sgivwfb.c:(.text+0x88c7f): undefined reference to `sgivwfb_mem_phys'
drivers/built-in.o: In function `sgivwfb_probe':
sgivwfb.c:(.init.text+0x4060): undefined reference to `sgivwfb_mem_size'
sgivwfb.c:(.init.text+0x4065): undefined reference to `sgivwfb_mem_phys'
sgivwfb.c:(.init.text+0x4076): undefined reference to `sgivwfb_mem_phys'
sgivwfb.c:(.init.text+0x409c): undefined reference to `sgivwfb_mem_size'
sgivwfb.c:(.init.text+0x410e): undefined reference to `sgivwfb_mem_size'
sgivwfb.c:(.init.text+0x4113): undefined reference to `sgivwfb_mem_phys'
sgivwfb.c:(.init.text+0x4162): undefined reference to `sgivwfb_mem_size'
sgivwfb.c:(.init.text+0x4168): undefined reference to `sgivwfb_mem_phys'
make: *** [.tmp_vmlinux1] Error 1
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Clean up and refactor i386 sub-architecture setup.
This change moves all the code from the
asm-i386/mach-*/setup_arch_pre/post.h headers, into
arch/i386/mach-*/setup.c. mach-*/setup_arch_pre.h is renamed to
setup_arch.h, and contains only things which should be in header files. It
is purely code-motion; there should be no functional changes at all.
Several functions in arch/i386/kernel/setup.c needed to be made non-static
so that they're visible to the code in mach-*/setup.c. asm-i386/setup.h is
used to hold the prototypes for these functions.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Cc: Martin Bligh <mbligh@google.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Andrey Panin <pazke@donpac.ru>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
>commit 76381fee7e
>Author: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
>Date: Thu Jun 23 00:08:46 2005 -0700
>
> [PATCH] xen: x86_64: use more usermode macro
>
> Make use of the user_mode macro where it's possible. This is useful for Xen
> because it will need only to redefine only the macro to a hypervisor call.
I am of the opinion that the above changeset is incomplete, i.e. it missed
converting some previous uses of user_mode to user_mode_vm. While most of
them could be considered just cosmetical, at least the one in die_nmi
doesn't appear to be.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Vincent Hanquez <vincent.hanquez@cl.cam.ac.uk>
Cc: Zachary Amsden <zach@vmware.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Commit f2b36db692 causes a bootup hang on
at least one machine. Revert for now until we understand why. The old
code may be ugly, but it works.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All kinds of ugliness exists because we don't initialize
the apics during init_IRQs.
- We calibrate jiffies in non apic mode even when we are using apics.
- We have to have special code to initialize the apics when non-smp.
- The legacy i8259 must exist and be setup correctly, even
when we won't use it past initialization.
- The kexec on panic code must restore the state of the io_apics.
- init/main.c needs a special case for !smp smp_init on x86
In addition to pure code movement I needed a couple
of non-obvious changes:
- Move setup_boot_APIC_clock into APIC_late_time_init for
simplicity.
- Use cpu_khz to generate a better approximation of loops_per_jiffies
so I can verify the timer interrupt is working.
- Call setup_apic_nmi_watchdog again after cpu_khz is initialized on
the boot cpu.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In file included from linux-2.6.13-rc5/arch/i386/kernel/timers/timer_pit.c:20:
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h: In function `do_timer_overflow':
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: `i8259A_lock' undeclared (first use in this function)
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: (Each undeclared identifier is reported only once
linux-2.6.13-rc5/include/asm-i386/mach-visws/do_timer.h:32: error: for each function it appears in.)
make[3]: *** [arch/i386/kernel/timers/timer_pit.o] Error 1
make[2]: *** [arch/i386/kernel/timers] Error 2
make[1]: *** [arch/i386/kernel] Error 2
make: *** [_all] Error 2
Signed-off-by: Tom Duffy <thomas.duffy.99@alumni.brown.edu>
Cc: Andrey Panin <pazke@orbita1.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is per Andi's request to remove NO_IOAPIC_CHECK from genapic and
use heuristics to prevent unique I/O APIC ID check for systems that don't
need it. The patch disables unique I/O APIC ID check for Xeon-based and
other platforms that don't use serial APIC bus for interrupt delivery.
Andi stated that AMD systems don't need unique IO_APIC_IDs either.
Signed-off-by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Cc: Andi Kleen <ak@muc.de>
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!
Ingo Molnar