David Howells
7d12e780e0
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
...
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)
2006-10-05 15:10:12 +01:00
..
mach-bigsmp
[PATCH] x86: convert bigsmp to use flat physical mode
2006-01-06 08:33:37 -08:00
mach-default
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
mach-es7000
[PATCH] i386: Allow to use GENERICARCH for UP kernels
2006-09-26 10:52:26 +02:00
mach-generic
[PATCH] x86: sutomatically enable bigsmp when we have more than 8 CPUs
2005-09-05 00:06:10 -07:00
mach-numaq
mach-summit
[PATCH] i383 numa: fix numaq/summit apicid conflict
2006-10-03 18:46:10 -07:00
mach-visws
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
mach-voyager
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
8253pit.h
a.out.h
acpi.h
[PATCH] i386: Replace i386 open-coded cmdline parsing with
2006-09-26 10:52:32 +02:00
agp.h
[PATCH] i386: inline asm cleanup
2005-09-05 00:06:11 -07:00
alternative-asm.i
Remove all inclusions of <linux/config.h>
2006-10-04 03:38:54 -04:00
alternative.h
[PATCH] i386: Remove alternative_smp
2006-08-30 16:05:15 -07:00
apic.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
apicdef.h
x86_64: Remove stale lapic definition from apicdef.h
2006-04-01 22:50:03 -05:00
arch_hooks.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
atomic.h
i386: improve and correct inline asm memory constraints
2006-07-08 15:24:18 -07:00
auxvec.h
[PATCH] auxiliary vector cleanups
2005-09-07 16:57:21 -07:00
bitops.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
boot.h
bug.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
bugs.h
[PATCH] namespaces: utsname: use init_utsname when appropriate
2006-10-02 07:57:21 -07:00
byteorder.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
cache.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
cacheflush.h
[PATCH] x86/x86_64: mark rodata section read only: x86 parts
2006-01-06 08:33:36 -08:00
checksum.h
[NET]: Fix ipl=>ihl typo in ip_fast_csum
2005-08-29 16:02:48 -07:00
cpu.h
[PATCH] Register sysfs file for hotplugged new node
2006-06-27 17:32:36 -07:00
cpufeature.h
[PATCH] x86_64: i386/x86-64 Add nmi watchdog support for new Intel CPUs
2006-06-26 10:48:22 -07:00
cputime.h
current.h
[PATCH] mark several functions __always_inline
2006-01-14 18:27:15 -08:00
debugreg.h
delay.h
[PATCH] Time: i386 Conversion - part 3: Enable Generic Timekeeping
2006-06-26 09:58:21 -07:00
desc.h
[PATCH] i386: Fix pack_descriptor()
2006-09-26 10:52:40 +02:00
div64.h
[PATCH] include/asm-i386/: "extern inline" -> "static inline"
2005-09-10 10:06:34 -07:00
dma-mapping.h
[PATCH] Use valid_dma_direction() in include/asm-i386/dma-mapping.h
2006-09-29 09:18:10 -07:00
dma.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
dmi.h
[PATCH] x86_64: Implement early DMI scanning
2006-03-25 09:10:55 -08:00
dwarf2.h
[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
2006-09-26 10:52:41 +02:00
e820.h
[PATCH] x86: Remove incorrect comment about ACPI e820 entries
2006-09-26 10:52:38 +02:00
edac.h
[PATCH] EDAC: core EDAC support code
2006-01-18 19:20:31 -08:00
elf.h
[PATCH] namespaces: utsname: switch to using uts namespaces
2006-10-02 07:57:21 -07:00
emergency-restart.h
[PATCH] i386: Implement machine_emergency_reboot
2005-07-26 14:35:42 -07:00
errno.h
fcntl.h
[PATCH] Clean up struct flock64 definitions
2005-09-07 16:57:38 -07:00
fixmap.h
[PATCH] x86: make __FIXADDR_TOP variable to allow it to make space for a hypervisor
2006-09-26 08:48:55 -07:00
floppy.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
frame.i
Remove all inclusions of <linux/config.h>
2006-10-04 03:38:54 -04:00
futex.h
i386: improve and correct inline asm memory constraints
2006-07-08 15:24:18 -07:00
genapic.h
[PATCH] i386: Allow to use GENERICARCH for UP kernels
2006-09-26 10:52:26 +02:00
hardirq.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
highmem.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
hpet.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
hw_irq.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
hypertransport.h
[PATCH] Initial generic hypertransport interrupt support
2006-10-04 07:55:29 -07:00
i387.h
[PATCH] i386: fix broken FP exception handling
2006-04-29 14:13:16 -07:00
i8253.h
[PATCH] x86: i8253/i8259A lock cleanup
2005-06-30 08:45:10 -07:00
i8259.h
ide.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
intel_arch_perfmon.h
[PATCH] x86: i386/x86-64 Add nmi watchdog support for new Intel CPUs
2006-09-26 10:52:27 +02:00
io.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
io_apic.h
[PATCH] genirq: i386 irq: Remove the msi assumption that irq == vector
2006-10-04 07:55:28 -07:00
ioctl.h
[PATCH] Generic ioctl.h
2006-01-10 08:01:34 -08:00
ioctls.h
ipc.h
ipcbuf.h
irq.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
irq_regs.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
irqflags.h
[PATCH] lockdep: irqtrace cleanup of include/asm-i386/irqflags.h
2006-07-03 15:27:03 -07:00
ist.h
k8.h
[PATCH] x86_64: Clean and enhance up K8 northbridge access code
2006-06-26 10:48:15 -07:00
Kbuild
[PATCH] Split i386 and x86_64 ptrace.h
2006-09-26 08:49:10 -07:00
kdebug.h
[PATCH] Notify page fault call chain for i386
2006-06-26 09:58:22 -07:00
kexec.h
[PATCH] i386: Avoid overwriting the current pgd (V4, i386)
2006-09-26 10:52:38 +02:00
kmap_types.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
kprobes.h
[PATCH] IA64: kprobe invalidate icache of jump buffer
2006-07-31 13:28:38 -07:00
ldt.h
linkage.h
local.h
i386: improve and correct inline asm memory constraints
2006-07-08 15:24:18 -07:00
math_emu.h
mc146818rtc.h
mca.h
mca_dma.h
[PATCH] kernel-doc for kernel/dma.c
2006-10-03 08:03:41 -07:00
mce.h
[PATCH] Don't trigger full rebuild via CONFIG_X86_MCE
2006-06-23 07:42:56 -07:00
mman.h
[PATCH] add asm-generic/mman.h
2006-02-15 15:32:22 -08:00
mmu.h
[PATCH] vdso: randomize the i386 vDSO by moving it into a vma
2006-06-27 17:32:38 -07:00
mmu_context.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
mmx.h
mmzone.h
[PATCH] convert i386 NUMA KVA space to bootmem
2006-09-26 08:48:45 -07:00
module.h
[PATCH] Base support for AMD Geode GX/LX processors
2006-01-06 08:33:38 -08:00
mpspec.h
[PATCH] mptspec: remove duplicate #include
2006-04-11 06:18:34 -07:00
mpspec_def.h
[PATCH] mpspec: remove unneeded packed attribute
2006-01-06 08:33:39 -08:00
msgbuf.h
msidef.h
[PATCH] genirq: i386 irq: Move msi message composition into io_apic.c
2006-10-04 07:55:28 -07:00
msr.h
[PATCH] x86: more asm cleanups
2005-09-05 00:06:12 -07:00
mtrr.h
[PATCH] Don't trigger full rebuild via CONFIG_MTRR
2006-06-23 07:42:56 -07:00
mutex.h
[PATCH] i386: Remove lock section support in mutex.h
2006-09-26 10:52:31 +02:00
namei.h
nmi.h
[PATCH] x86: Clean up x86 NMI sysctls
2006-09-30 01:47:55 +02:00
numa.h
[PATCH] x86-64: Use ACPI PXM to parse PCI<->node assignments
2005-09-12 10:49:57 -07:00
numaq.h
page.h
[PATCH] vdso: randomize the i386 vDSO by moving it into a vma
2006-06-27 17:32:38 -07:00
param.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
parport.h
pci-direct.h
pci.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
percpu.h
pgalloc.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
pgtable-2level-defs.h
pgtable-2level.h
[PATCH] paravirt: optimize ptep establish for pae
2006-10-01 00:39:34 -07:00
pgtable-3level-defs.h
pgtable-3level.h
[PATCH] paravirt: remove set pte atomic
2006-10-01 00:39:34 -07:00
pgtable.h
[PATCH] paravirt: update pte hook
2006-10-01 00:39:34 -07:00
poll.h
[PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications
2006-03-25 08:22:56 -08:00
posix_types.h
i386: improve and correct inline asm memory constraints
2006-07-08 15:24:18 -07:00
processor.h
[PATCH] x86: roll all the cpuid asm into one __cpuid call
2006-09-26 08:48:55 -07:00
ptrace-abi.h
[PATCH] Split i386 and x86_64 ptrace.h
2006-09-26 08:49:10 -07:00
ptrace.h
[PATCH] Add regs_return_value() helper
2006-10-02 07:57:16 -07:00
resource.h
rtc.h
rwlock.h
[PATCH] i386: Clean up spin/rwlocks
2006-09-26 10:52:32 +02:00
rwsem.h
[PATCH] i386: Remove lock section support in rwsem.h
2006-09-26 10:52:31 +02:00
scatterlist.h
seccomp.h
sections.h
segment.h
[PATCH] i386: Allow a kernel not to be in ring 0
2006-09-26 10:52:39 +02:00
semaphore.h
[PATCH] i386: Use early clobbers for semaphores now
2006-09-27 14:39:51 -07:00
sembuf.h
serial.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
setup.h
[PATCH] headers_check: don't expose PFN stuff to userspace in <asm-i386/setup.h>
2006-09-13 07:32:16 -07:00
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h
[PATCH] headers_check: move inclusion of <linux/linkage.h> in <asm-i386/signal.h>
2006-09-13 07:32:15 -07:00
smp.h
[PATCH] stack overflow safe kdump: safe_smp_processor_id()
2006-10-01 00:39:30 -07:00
socket.h
[AF_UNIX]: Datagram getpeersec
2006-06-29 16:58:06 -07:00
sockios.h
sparsemem.h
spinlock.h
[PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks
2006-10-01 00:39:21 -07:00
spinlock_types.h
[PATCH] spinlock consolidation
2005-09-10 10:06:21 -07:00
srat.h
stacktrace.h
[PATCH] i386: Do stacktracer conversion too
2006-09-26 10:52:34 +02:00
stat.h
[PATCH] 2TB files: st_blocks is invalid when calling stat64
2006-03-26 08:57:00 -08:00
statfs.h
string.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
suspend.h
sync_bitops.h
[PATCH] x86: implement always-locked bit ops, for memory shared with an SMP hypervisor
2006-09-26 08:48:55 -07:00
system.h
[PATCH] x86: implement always-locked bit ops, for memory shared with an SMP hypervisor
2006-09-26 08:48:55 -07:00
termbits.h
termios.h
therm_throt.h
[PATCH] x86: Add a cumulative thermal throttle event counter.
2006-09-26 10:52:42 +02:00
thread_info.h
[PATCH] i386: use thread_info flags for debug regs and IO bitmaps
2006-07-09 18:47:12 -07:00
timer.h
[PATCH] Time: i386 Conversion - part 3: Enable Generic Timekeeping
2006-06-26 09:58:21 -07:00
timex.h
[PATCH] Time: i386 Conversion - part 2: Rework TSC Support
2006-06-26 09:58:21 -07:00
tlb.h
tlbflush.h
[PATCH] i386: Minor fixes & cleanup to tlb flush
2006-09-26 10:52:29 +02:00
topology.h
[PATCH] sched: introduce child field in sched_domain
2006-10-03 08:04:06 -07:00
tsc.h
[PATCH] x86: remove config.h includes from asm-i386 & asm-x86_64
2006-09-26 10:52:36 +02:00
types.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
uaccess.h
[PATCH] Make copy_from_user_inatomic NOT zero the tail on i386
2006-06-25 10:01:09 -07:00
ucontext.h
unaligned.h
unistd.h
[PATCH] remove remaining errno and __KERNEL_SYSCALLS__ references
2006-10-02 07:57:23 -07:00
unwind.h
[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
2006-09-26 10:52:41 +02:00
user.h
vga.h
[PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use
2006-06-22 15:05:58 -07:00
vic.h
vm86.h
[PATCH] Make vm86 support optional
2006-01-08 20:14:11 -08:00
voyager.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
xor.h
[PATCH] i386: inline asm cleanup
2005-09-05 00:06:11 -07:00