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)
* master.kernel.org:/pub/scm/linux/kernel/git/davej/configh:
Remove all inclusions of <linux/config.h>
Manually resolved trivial path conflicts due to removed files in
the sound/oss/ subdirectory.
* master.kernel.org:/pub/scm/linux/kernel/git/willy/parisc-2.6: (41 commits)
[PARISC] Kill wall_jiffies use
[PARISC] Honour "panic_on_oops" sysctl
[PARISC] Fix fs/binfmt_som.c
[PARISC] Export clear_user_page to modules
[PARISC] Make DMA routines more stubby
[PARISC] Define pci_get_legacy_ide_irq
[PARISC] Fix CONFIG_DEBUG_SPINLOCK
[PARISC] Fix HPUX compat compile with current GCC
[PARISC] Fix iounmap compile warning
[PARISC] Add support for Quicksilver AGPGART
[PARISC] Move LBA and SBA register defines to the common ropes.h
[PARISC] Create shared <asm/ropes.h> header
[PARISC] Stash the lba_device in its struct device drvdata
[PARISC] Generalize IS_ASTRO et al to take a parisc_device like
[PARISC] Pretty print the name of the lba type on kernel boot
[PARISC] Remove some obsolete comments and I checked that Reo is similar to Ike
[PARISC] Add hardware found in the rp8400
[PARISC] Allow nested interrupts
[PARISC] Further updates to timer_interrupt()
[PARISC] remove halftick and copy clocktick to local var (gcc can optimize usage)
...
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (25 commits)
[POWERPC] Add support for the mpc832x mds board
[POWERPC] Add initial support for the e300c2 core
[POWERPC] Add MPC8360EMDS default dts file
[POWERPC] Add MPC8360EMDS board support
[POWERPC] Add QUICC Engine (QE) infrastructure
[POWERPC] Add QE device tree node definition
[POWERPC] Don't try to just continue if xmon has no input device
[POWERPC] Fix a printk in pseries_mpic_init_IRQ
[POWERPC] Get default baud rate in udbg_scc
[POWERPC] Fix zImage.coff on oldworld PowerMac
[POWERPC] Fix xmon=off and cleanup xmon initialisation
[POWERPC] Cleanup include/asm-powerpc/xmon.h
[POWERPC] Update swim3 printk after blkdev.h change
[POWERPC] Cell interrupt rework
POWERPC: mpc82xx merge: board-specific/platform stuff(resend)
POWERPC: 8272ads merge to powerpc: common stuff
POWERPC: Added devicetree for mpc8272ads board
[POWERPC] iSeries has no legacy I/O
[POWERPC] implement BEGIN/END_FW_FTR_SECTION
[POWERPC] iSeries does not need pcibios_fixup_resources
...
serial167, remove useless tty check
tty is dereferenced before it is checked to be non-NULL. Remove such
check.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
char, another tmp_buf cleanup
No need to allocate one page as a side buffer. It's no more used. Clean this
(de)allocs of this useless memory pages in char subtree.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* 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>
Now that devfs is removed, there's no longer any need to document how to
do this or that with devfs.
This patch includes some improvements by Joe Perches.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
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>
As per feature-removal-schedule.txt.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (29 commits)
[POWERPC] Fix rheap alignment problem
[POWERPC] Use check_legacy_ioport() for ISAPnP
[POWERPC] Avoid NULL pointer in gpio1_interrupt
[POWERPC] Enable generic rtc hook for the MPC8349 mITX
[POWERPC] Add powerpc get/set_rtc_time interface to new generic rtc class
[POWERPC] Create a "wrapper" script and use it in arch/powerpc/boot
[POWERPC] fix spin lock nesting in hvc_iseries
[POWERPC] EEH failure to mark pci slot as frozen.
[POWERPC] update powerpc defconfig files after libata kconfig breakage
[POWERPC] enable sysrq in pmac32_defconfig
[POWERPC] UPIO_TSI cleanup
[POWERPC] rewrite mkprep and mkbugboot in sane C
[POWERPC] maple/pci iomem annotations
[POWERPC] powerpc oprofile __user annotations
[POWERPC] cell spufs iomem annotations
[POWERPC] NULL noise removal: spufs
[POWERPC] ppc math-emu needs -fno-builtin-fabs for math.c and fabs.c
[POWERPC] update mpc8349_itx_defconfig and remove some debug settings
[POWERPC] Always call cede in pseries dedicated idle loop
[POWERPC] Fix loop logic in irq_alloc_virt()
...
tipar: repair nonexistant pr_debug argument use
I guessed what the pr_debug meant by 'data'.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds proper prototypes to header files for three console init
functions used on drivers/char/vt.c
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Check the return value of device_create_file(). If return is 'fail', remove
attributes by calling device_remove_file().
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
After the previous patch to disable the kernel IPMI daemon if interrupts
were available, the issue of broken hardware was raised, and a reasonable
request to add an override was mode. So here it is.
Allow the user to force the kernel ipmi daemon on or off. This way,
hardware with broken interrupts or users that are not concerned with
performance can turn it on or off to their liking.
[akpm@osdl.org: save 4 bytes in vmlinux]
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Kill warning:
drivers/char/ip2/ip2main.c: In function âip2_loadmainâ:
drivers/char/ip2/ip2main.c:782: warning: label âout_classâ defined but not used
This driver's initialization (and cleanup of errors during init) is
extremely convoluted, and could stand to be transformed into the standard
unwinding-goto style of error cleanup.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
gcc issues the following warning:
drivers/char/ipmi/ipmi_si_intf.c: In function âinit_ipmi_siâ:
drivers/char/ipmi/ipmi_si_intf.c:1729: warning: âdata.irqâ may be used uninitialized in this function
This is indeed a bug. data.irq is completely uninitialized in some code
paths. Worse than that, data from a previous decode_dmi() run can easily
leak through successive calls.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (35 commits)
Input: wistron - add support for Acer TravelMate 2424NWXCi
Input: wistron - fix setting up special buttons
Input: add KEY_BLUETOOTH and KEY_WLAN definitions
Input: add new BUS_VIRTUAL bus type
Input: add driver for stowaway serial keyboards
Input: make input_register_handler() return error codes
Input: remove cruft that was needed for transition to sysfs
Input: fix input module refcounting
Input: constify input core
Input: libps2 - rearrange exports
Input: atkbd - support Microsoft Natural Elite Pro keyboards
Input: i8042 - disable MUX mode on Toshiba Equium A110
Input: i8042 - get rid of polling timer
Input: send key up events at disconnect
Input: constify psmouse driver
Input: i8042 - add Amoi to the MUX blacklist
Input: logips2pp - add sugnature 56 (Cordless MouseMan Wheel), cleanup
Input: add driver for Touchwin serial touchscreens
Input: add driver for Touchright serial touchscreens
Input: add driver for Penmount serial touchscreens
...
There are a few places in the kernel where the init task is signaled. The
ctrl+alt+del sequence is one them. It kills a task, usually init, using a
cached pid (cad_pid).
This patch replaces the pid_t by a struct pid to avoid pid wrap around
problem. The struct pid is initialized at boot time in init() and can be
modified through systctl with
/proc/sys/kernel/cad_pid
[ I haven't found any distro using it ? ]
It also introduces a small helper routine kill_cad_pid() which is used
where it seemed ok to use cad_pid instead of pid 1.
[akpm@osdl.org: cleanups, build fix]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Replace references to system_utsname to the per-process uts namespace
where appropriate. This includes things like uname.
Changes: Per Eric Biederman's comments, use the per-process uts namespace
for ELF_PLATFORM, sunrpc, and parts of net/ipv4/ipconfig.c
[jdike@addtoit.com: UML fix]
[clg@fr.ibm.com: cleanup]
[akpm@osdl.org: build fix]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andrey Savochkin <saw@sw.ru>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking. One of these
structures was a struct tty_operations. In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.
This patch declares all struct tty_operations in the tree as const. In all
cases, they are static and used only as input to tty_set_operations. As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.
53 drivers are affected. I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months. serial_core.c was the busiest one that I looked at.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I took a good hard look at the locking and it appears the locking on vt_pid
is the console semaphore. Every modified path is called under the console
semaphore except reset_vc when it is called from fn_SAK or do_SAK both of
which appear to be in interrupt context. In addition I need to be careful
because in the presence of an oops the console_sem may be arbitrarily
dropped.
Which leads me to conclude the current locking is inadequate for my needs.
Given the weird cases we could hit because of oops printing instead of
introducing an extra spin lock to protect the data and keep the pid to
signal and the signal to send in sync, I have opted to use xchg on just the
struct pid * pointer instead.
Due to console_sem we will stay in sync between vt_pid and vt_mode except
for a small window during a SAK, or oops handling. SAK handling should
kill any user space process that care, and oops handling we are broken
anyway. Besides the worst that can happen is that I try to send the wrong
signal.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is such a rare path it took me a while to figure out how to test
this after soring out the locking.
This patch does several things.
- The variables used are moved into a structure and declared in vt_kern.h
- A spinlock is added so we don't have SMP races updating the values.
- Instead of raw pid_t value a struct_pid is used to guard against
pid wrap around issues, if the daemon to spawn a new console dies.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
asm/serial.h is supposed to contain the definitions for the architecture
specific 8250 ports for the 8250 driver. It may also define BASE_BAUD,
but this is the base baud for the architecture specific ports _only_.
Therefore, nothing other than the 8250 driver should be including this
header file. In order to move towards this goal, here is a patch which
removes some of the more obvious incorrect includes of the file.
Acked-by: Paul Fulghum <paulkf@microgate.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch cleans up generic_file_*_read/write() interfaces. Christoph
Hellwig gave me the idea for this clean ups.
In a nutshell, all filesystems should set .aio_read/.aio_write methods and use
do_sync_read/ do_sync_write() as their .read/.write methods. This allows us
to cleanup all variants of generic_file_* routines.
Final available interfaces:
generic_file_aio_read() - read handler
generic_file_aio_write() - write handler
generic_file_aio_write_nolock() - no lock write handler
__generic_file_aio_write_nolock() - internal worker routine
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes readv() and writev() methods and replaces them with
aio_read()/aio_write() methods.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch vectorizes aio_read() and aio_write() methods to prepare for
collapsing all aio & vectored operations into one interface - which is
aio_read()/aio_write().
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Michael Holzheu <HOLZHEU@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
