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)
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (39 commits)
Add missing maintainer countries in CREDITS
Fix bytes <-> kilobytes typo in Kconfig for ramdisk
fix a typo in Documentation/pi-futex.txt
BUG_ON conversion for fs/xfs/
BUG_ON() conversion in fs/nfsd/
BUG_ON conversion for fs/reiserfs
BUG_ON cleanups in arch/i386
BUG_ON cleanup in drivers/net/tokenring/
BUG_ON cleanup for drivers/md/
kerneldoc-typo in led-class.c
debugfs: spelling fix
rcutorture: Fix incorrect description of default for nreaders parameter
parport: Remove space in function calls
Michal Wronski: update contact info
Spelling fix: "control" instead of "cotrol"
reboot parameter in Documentation/kernel-parameters.txt
Fix copy&waste bug in comment in scripts/kernel-doc
remove duplicate "until" from kernel/workqueue.c
ite_gpio fix tabbage
fix file specification in comments
...
Fixed trivial path conflicts due to removed files:
arch/mips/dec/boot/decstation.c, drivers/char/ite_gpio.c
Many files include the filename at the beginning, serveral used a wrong one.
Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Return ENOTTY instead of ENOIOCTLCMD in user-visible ioctl() results
The watchdog drivers used to return ENOIOCTLCMD for bad ioctl() commands.
ENOIOCTLCMD should not be visible by the user, so use ENOTTY instead.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Since we are using the device driver model,
we don't need to arrange the shutdown via a
reboot_notifier.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
for_each_pci_dev calls pci_get_device (and thus
it calls pci_dev_get). So we need to do a pci_dev_put
to keep the refcounting correct.
(Thanks to Jiri Slaby <jirislaby@gmail.com>)
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Hardware driver for the intel TCO timer based watchdog devices.
These drivers are included in the Intel 82801 I/O Controller
Hub family (from ICH0 up to ICH7) and in the Intel 6300ESB
controller hub.
This driver will replace the i8xx_tco.c driver.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
On a machine with no machzwd, loading the module prints out..
machzwd: MachZ ZF-Logic Watchdog driver initializing.
0xffff
machzwd: Watchdog using action = RESET
- the 0xffff printk is unnecessary
- 0xffff seems to be 'hardware not present'
- fix CodingStyle. (This driver could use some more work here)
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Return ENOTTY instead of ENOIOCTLCMD in user-visible ioctl() results
The watchdog drivers used to return ENOIOCTLCMD for bad ioctl() commands.
ENOIOCTLCMD should not be visible by the user, so use ENOTTY instead.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
If the driver is not configured for `no way out`,
then the open method should not automatically allow
the setting of allow_close to CLOSE_STATE_ALLOW.
The setting of allow_close nullifies the use of
the magic close via the write path. It means that
in the default state, the watchdog will shut-down
even if the magic close has not been issued.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Add io spinlocks to prevent possible race
conditions between start and stop operations
that are issued from different child processes
where the master process opened /dev/watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Change remove code so that we first detach
the driver from userspace, then clean up the
clock and then clean up the memory we allocated.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Add watchdog support for Philips PNX4008 ARM board inlined.
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Use refcounting for pci device obtaining.
Use PCI_DEVICE macro.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Andrew Morton <akpm@osdl.org>
Convert pci_find_device to pci_get_device + pci_dev_put
in alim watchdog cards' drivers (refcounting).
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
In some applications people have expressed a need for an mmap() method,
so we implement a simple stub for this that maps back a page with the
counter in it.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We had quite a bit of whitespace damage, clean most of it up..
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Arthur Othieno <a.othieno@bluewin.ch>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The last argument of module_param is permissions, not default value.
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Three typos in drivers/char/watchdog/Kconfig...
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Mark the static struct file_operations in drivers/char as const. Making
them const prevents accidental bugs, and moves them to the .rodata section
so that they no longer do any false sharing; in addition with the proper
debug option they are then protected against corruption..
[akpm@osdl.org: build fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Converted to a platform driver.
Added suspend/resume support - the watchdog is disabled during the
sleep states.
Original patch from David Brownell.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Some watchdog drivers have the ability to report the remaining time
before the system will reboot. With the WDIOC_GETTIMELEFT ioctl
you can now read the time left before the watchdog would reboot
your system.
The following drivers support this new IOCTL:
i8xx_tco.c, pcwd_pci.c and pcwd_usb.c .
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
If the s3c2410 watchdog timer is not enabled by
the driver at startup, ensure that it is stopped
in-case the boot process has enabled it.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Temporary remove support for ICH6 + ICH7. In these newer TCO's
the watchdog timer has changed: the TCO_TMR register is not at
the TCOBASE+0x1 offset, but changed it's place to TCOBASE+0x12
and became 10 bit long [0:9]. (Kernel BUG 6031).
ICH6 + ICH7 support will be added in a new driver. Code is
under test.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Fix printk output.
sc1200wdt: build 20020303<3>sc1200wdt: io parameter must be specified
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Watchdog driver for the Atmel AT91RM9200 processor.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
The Coverity checker noted that this resulted in a NULL pointer
reference if we were coming from
if (usb_pcwd == NULL) {
printk(KERN_ERR PFX "Out of memory\n");
goto error;
}
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
change sprintf(pcwd_private.fw_ver_str, "ERROR");
to strcpy... as pointed out by Andrew Morton.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
removal of includes (since we don't use kmalloc and
TASK_INTERRUPTABLE anymore).
Addition of missing commands.
Printk that lets the user know when the module was
unloaded.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Clean-up the control status code (insert tabs where relevant),
Add new Control Status defines, Make sure that the R2DS bit
stays the same.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Add a driver for the on-chip watchdog on the cirrus ep93xx series of ARM
CPUs.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
mv64x600_wdt: convert to the new platform device interface Do not use
platform_device_register_simple() as it is going away.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
platform_get_irq*() now returns on -ENXIO when the resource cannot be
found. Ensure all users of platform_get_irq*() handle this error
appropriately.
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Rename get_support function to pcwd_check_temperature_support
so that it is clearer what the function does.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
David Howells