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
..
iseries
[POWERPC] Merge iSeries i/o operations with the rest
2006-09-22 15:19:58 +10:00
8253pit.h
a.out.h
abs_addr.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
agp.h
asm-compat.h
atomic.h
power: improve inline asm memory constraints
2006-07-08 15:00:28 -07:00
auxvec.h
backlight.h
[PATCH] powermac: More powermac backlight fixes
2006-07-31 13:28:45 -07:00
bitops.h
power: improve inline asm memory constraints
2006-07-08 15:00:28 -07:00
bootx.h
btext.h
bug.h
[PATCH] Let WARN_ON/WARN_ON_ONCE return the condition
2006-09-29 09:18:06 -07:00
bugs.h
byteorder.h
cache.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
cacheflush.h
checksum.h
compat.h
[PATCH] powerpc signal __user annotations
2006-02-08 01:03:46 -05:00
cputable.h
[POWERPC] powerpc: PA6T cputable entry, PVR value
2006-09-13 18:39:52 +10:00
cputime.h
[PATCH] powerpc: implement missing jiffies64_to_cputime64()
2006-07-05 09:39:54 -07:00
current.h
dbdma.h
delay.h
[POWERPC] Fix mdelay badness on shared processor partitions
2006-06-21 15:01:33 +10:00
div64.h
dma-mapping.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
dma.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
eeh.h
[POWERPC] Fix MMIO ops to provide expected barrier behaviour
2006-09-13 22:08:26 +10:00
eeh_event.h
[PATCH] powerpc/pseries: clear PCI failure counter if no new failures
2006-04-22 18:46:13 +10:00
elf.h
Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
2006-06-22 22:11:30 -07:00
emergency-restart.h
errno.h
fcntl.h
firmware.h
[POWERPC] implement BEGIN/END_FW_FTR_SECTION
2006-10-03 16:50:21 +10:00
floppy.h
[PATCH] irq-flags: POWERPC: Use the new IRQF_ constants
2006-07-02 13:58:47 -07:00
fs_pd.h
POWERPC: Get rid of remapping the whole immr
2006-09-21 22:37:58 +04:00
futex.h
[POWERPC] Implement PowerPC futex_atomic_cmpxchg_inatomic().
2006-09-13 18:28:41 +10:00
grackle.h
hardirq.h
heathrow.h
hvcall.h
[POWERPC] powerpc: Instrument Hypervisor Calls
2006-09-13 18:39:53 +10:00
hvconsole.h
[PATCH] powerpc: hvc_console updates
2006-03-28 16:45:26 +11:00
hvcserver.h
hw_irq.h
[PATCH] genirq: add ->retrigger() irq op to consolidate hw_irq_resend()
2006-06-29 10:26:23 -07:00
i8259.h
[POWERPC] Add new interrupt mapping core and change platforms to use it
2006-07-03 21:36:01 +10:00
ibmebus.h
[POWERPC] Constify & voidify get_property()
2006-07-31 15:55:04 +10:00
ide.h
[POWERPC] clean up ide io accessors
2006-09-20 14:06:18 +10:00
immap_86xx.h
[POWERPC] Add 8641 Register space and IRQ definitions.
2006-06-21 15:01:28 +10:00
immap_qe.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
io.h
[PATCH] restore parport_pc probing on powermac
2006-10-03 08:03:41 -07:00
ioctl.h
ioctls.h
iommu.h
Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
2006-06-22 22:11:30 -07:00
ipc.h
ipcbuf.h
ipic.h
fix file specification in comments
2006-10-03 23:01:26 +02:00
irq.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +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 subsystem, core
2006-07-03 15:27:03 -07:00
Kbuild
[HEADERS] One line per header in Kbuild files to reduce conflicts
2006-09-19 12:43:58 +01:00
kdebug.h
[PATCH] Notify page fault call chain for powerpc
2006-06-26 09:58:22 -07:00
kdump.h
[POWERPC] kdump: Support kernels having 64k page size.
2006-09-13 18:30:04 +10:00
kexec.h
[POWERPC] Make crash.c work on 32-bit and 64-bit
2006-08-17 16:41:10 +10:00
keylargo.h
kmap_types.h
kprobes.h
[PATCH] kprobes: handle symbol resolution when <module:.symbol> is specified
2006-10-02 07:57:16 -07:00
linkage.h
lmb.h
[PATCH] powerpc: Remove calculation of io hole
2006-03-22 15:04:30 +11:00
local.h
lppaca.h
[POWERPC] Update lppaca offset comments
2006-08-08 17:08:58 +10:00
machdep.h
[POWERPC] Add new interrupt mapping core and change platforms to use it
2006-07-03 21:36:01 +10:00
macio.h
mc146818rtc.h
mediabay.h
mman.h
[PATCH] add asm-generic/mman.h
2006-02-15 15:32:22 -08:00
mmu.h
[POWERPC] powerpc: Initialise ppc_md htab pointers earlier
2006-06-28 11:59:47 +10:00
mmu_context.h
[POWERPC] Correct the MAX_CONTEXT definition
2006-06-29 16:16:15 +10:00
mmzone.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
module.h
mpc85xx.h
POWERPC: Add support for the mpc8560 eval board
2006-09-21 22:31:26 +04:00
mpc86xx.h
[POWERPC] Use mpc8641hpcn PIC base address from dev tree.
2006-08-25 14:32:13 +10:00
mpic.h
[POWERPC] Support for "weird" MPICs and fixup mpc7448_hpc2
2006-08-30 14:29:42 +10:00
msgbuf.h
mutex.h
namei.h
nvram.h
of_device.h
typo fixes: mecanism -> mechanism
2006-06-30 18:20:44 +02:00
ohare.h
oprofile_impl.h
[PATCH] powerpc: Remove oprofile spinlock backtrace code
2006-03-29 13:44:16 +11:00
paca.h
Merge branch 'linux-2.6'
2006-09-14 07:07:18 +10:00
page.h
[POWERPC] Remove DISCONTIGMEM cruft from page.h
2006-09-22 15:19:58 +10:00
page_32.h
page_64.h
[PATCH] powerpc: Fix pagetable bloat for hugepages
2006-04-28 15:02:51 +10:00
param.h
parport.h
[PATCH] powerpc: parallel port init fix
2006-01-11 14:49:24 +11:00
pci-bridge.h
Remove all inclusions of <linux/config.h>
2006-10-04 03:38:54 -04:00
pci.h
[PATCH] 64bit resource: change pci core and arch code to use resource_size_t
2006-06-27 09:24:00 -07:00
percpu.h
[PATCH] lockdep: add per_cpu_offset()
2006-07-03 15:27:00 -07:00
pgalloc.h
[POWERPC] hugepage BUG fix
2006-08-24 10:07:23 +10:00
pgtable-4k.h
[PATCH] Standardize pxx_page macros
2006-09-26 08:48:51 -07:00
pgtable-64k.h
powerpc: Use 64k pages without needing cache-inhibited large pages
2006-06-15 10:45:18 +10:00
pgtable.h
[PATCH] Standardize pxx_page macros
2006-09-26 08:48:51 -07:00
pmac_feature.h
[PATCH] powerpc: Kill _machine and hard-coded platform numbers
2006-03-28 23:15:54 +11:00
pmac_low_i2c.h
pmac_pfunc.h
typo fixes: mecanism -> mechanism
2006-06-30 18:20:44 +02:00
pmc.h
poll.h
[PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications
2006-03-25 08:22:56 -08:00
posix_types.h
ppc-pci.h
[POWERPC] EEH: enable MMIO/DMA on frozen slot
2006-09-21 22:59:14 +10:00
ppc_asm.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
processor.h
[POWERPC] Add briq support to CHRP
2006-07-07 20:19:15 +10:00
prom.h
[POWERPC] Define of_read_ulong helper
2006-09-20 15:09:48 +10:00
pSeries_reconfig.h
ptrace.h
[PATCH] Add regs_return_value() helper
2006-10-02 07:57:16 -07:00
qe.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
qe_ic.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
reg.h
[POWERPC] powerpc: PA6T cputable entry, PVR value
2006-09-13 18:39:52 +10:00
reg_8xx.h
resource.h
rtas.h
[POWERPC] Add a helper for calculating RTAS "config_addr" parameters
2006-08-25 13:27:35 +10:00
rtc.h
rwsem.h
[PATCH] lockdep: remove RWSEM_DEBUG remnants
2006-07-03 15:27:01 -07:00
scatterlist.h
seccomp.h
sections.h
semaphore.h
sembuf.h
serial.h
powerpc: Introduce a new config symbol to control 16550 early debug code
2006-01-10 16:19:05 +11:00
setup.h
shmbuf.h
shmparam.h
sigcontext.h
siginfo.h
signal.h
[PATCH] irq-flags: POWERPC: Use the new IRQF_ constants
2006-07-02 13:58:47 -07:00
smp.h
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
2006-10-05 15:10:12 +01:00
smu.h
[POWERPC] powermac: Constify & voidify get_property()
2006-07-31 15:55:05 +10:00
socket.h
[AF_UNIX]: Datagram getpeersec
2006-06-29 16:58:06 -07:00
sockios.h
sparsemem.h
spinlock.h
[PATCH] Directed yield: direct yield of spinlocks for powerpc
2006-10-01 00:39:22 -07:00
spinlock_types.h
spu.h
[POWERPC] spufs: add infrastructure for finding elf objects
2006-10-05 09:21:02 +10:00
spu_csa.h
[POWERPC] spufs: one more fix for 64k pages
2006-06-21 15:01:32 +10:00
spu_priv1.h
[POWERPC] spufs: fix spu irq affinity setting
2006-06-21 15:01:31 +10:00
sstep.h
stat.h
statfs.h
string.h
powerpc: fix strncasecmp prototype
2006-03-25 09:41:40 -08:00
synch.h
[PATCH] powerpc: newline for ISYNC_ON_SMP
2006-02-24 14:06:00 +11:00
syscalls.h
[PATCH] powerpc: declare arch syscalls in <asm/syscalls.h>
2006-03-27 14:48:22 +11:00
systbl.h
[POWERPC] Unify ppc syscall tables
2006-06-21 15:01:32 +10:00
system.h
[POWERPC] Cleanup include/asm-powerpc/xmon.h
2006-10-04 14:52:17 +10:00
tce.h
[PATCH] powerpc: kill union tce_entry
2006-04-29 18:07:54 +10:00
termbits.h
[PATCH] Add CMSPAR to termbits.h for powerpc and alpha
2006-05-26 11:55:46 -07:00
termios.h
thread_info.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
time.h
[POWERPC] Add powerpc get/set_rtc_time interface to new generic rtc class
2006-10-02 17:48:47 +10:00
timex.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
tlb.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
tlbflush.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
todc.h
[POWERPC] todc: add support for Time-Of-Day-Clock
2006-06-29 16:22:46 +10:00
topology.h
[PATCH] sched: introduce child field in sched_domain
2006-10-03 08:04:06 -07:00
tsi108.h
[POWERPC] Update mpc7448hpc2 board irq support using device tree
2006-08-23 15:51:18 +10:00
tsi108_irq.h
[POWERPC] Update mpc7448hpc2 board irq support using device tree
2006-08-23 15:51:18 +10:00
types.h
Don't include linux/config.h from anywhere else in include/
2006-04-26 12:56:16 +01:00
uaccess.h
powerpc: Fix incorrect might_sleep in __get_user/__put_user on kernel addresses
2006-05-03 23:06:46 +10:00
ucc.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
ucc_fast.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
ucc_slow.h
[POWERPC] Add QUICC Engine (QE) infrastructure
2006-10-04 15:24:27 +10:00
ucontext.h
udbg.h
[POWERPC] Add udbg support for RTAS console
2006-06-28 11:59:48 +10:00
unaligned.h
uninorth.h
unistd.h
[PATCH] rename the provided execve functions to kernel_execve
2006-10-02 07:57:23 -07:00
user.h
vdso.h
vdso_datapage.h
[PATCH] powerpc: Kill _machine and hard-coded platform numbers
2006-03-28 23:15:54 +11:00
vga.h
[PATCH] vgacon: make VGA_MAP_MEM take size, remove extra use
2006-06-22 15:05:58 -07:00
vio.h
[POWERPC] Constify & voidify get_property()
2006-07-31 15:55:04 +10:00
xmon.h
[POWERPC] Fix xmon=off and cleanup xmon initialisation
2006-10-04 14:52:22 +10:00
xor.h