2005-04-17 06:20:36 +08:00
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/* -*- linux-c -*-
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*
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* $Id: sysrq.c,v 1.15 1998/08/23 14:56:41 mj Exp $
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*
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* Linux Magic System Request Key Hacks
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*
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* (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
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* based on ideas by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>
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*
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* (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
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* overhauled to use key registration
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* based upon discusions in irc://irc.openprojects.net/#kernelnewbies
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*/
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#include <linux/sched.h>
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#include <linux/interrupt.h>
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#include <linux/mm.h>
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#include <linux/fs.h>
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#include <linux/tty.h>
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#include <linux/mount.h>
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#include <linux/kdev_t.h>
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#include <linux/major.h>
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#include <linux/reboot.h>
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#include <linux/sysrq.h>
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#include <linux/kbd_kern.h>
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2008-10-16 13:04:23 +08:00
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#include <linux/proc_fs.h>
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2009-08-02 17:28:21 +08:00
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#include <linux/nmi.h>
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2005-04-17 06:20:36 +08:00
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#include <linux/quotaops.h>
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perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 18:02:48 +08:00
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#include <linux/perf_event.h>
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2005-04-17 06:20:36 +08:00
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/suspend.h>
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#include <linux/writeback.h>
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#include <linux/buffer_head.h> /* for fsync_bdev() */
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#include <linux/swap.h>
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#include <linux/spinlock.h>
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#include <linux/vt_kern.h>
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#include <linux/workqueue.h>
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2007-02-16 17:28:16 +08:00
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#include <linux/hrtimer.h>
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2007-10-17 14:25:53 +08:00
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#include <linux/oom.h>
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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
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#include <linux/slab.h>
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2005-04-17 06:20:36 +08:00
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#include <asm/ptrace.h>
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2006-10-06 22:38:42 +08:00
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#include <asm/irq_regs.h>
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2005-04-17 06:20:36 +08:00
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/* Whether we react on sysrq keys or just ignore them */
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2006-12-13 16:34:36 +08:00
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int __read_mostly __sysrq_enabled = 1;
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static int __read_mostly sysrq_always_enabled;
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int sysrq_on(void)
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{
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return __sysrq_enabled || sysrq_always_enabled;
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}
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/*
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* A value of 1 means 'all', other nonzero values are an op mask:
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*/
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static inline int sysrq_on_mask(int mask)
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{
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return sysrq_always_enabled || __sysrq_enabled == 1 ||
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(__sysrq_enabled & mask);
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}
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static int __init sysrq_always_enabled_setup(char *str)
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{
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sysrq_always_enabled = 1;
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printk(KERN_INFO "debug: sysrq always enabled.\n");
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return 1;
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}
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__setup("sysrq_always_enabled", sysrq_always_enabled_setup);
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2005-04-17 06:20:36 +08:00
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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 21:55:46 +08:00
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static void sysrq_handle_loglevel(int key, struct tty_struct *tty)
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2005-04-17 06:20:36 +08:00
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{
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int i;
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i = key - '0';
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console_loglevel = 7;
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printk("Loglevel set to %d\n", i);
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console_loglevel = i;
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2006-03-25 19:07:08 +08:00
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}
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2005-04-17 06:20:36 +08:00
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static struct sysrq_key_op sysrq_loglevel_op = {
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.handler = sysrq_handle_loglevel,
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2009-01-07 06:41:13 +08:00
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.help_msg = "loglevel(0-9)",
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2005-04-17 06:20:36 +08:00
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.action_msg = "Changing Loglevel",
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.enable_mask = SYSRQ_ENABLE_LOG,
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};
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#ifdef CONFIG_VT
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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 21:55:46 +08:00
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static void sysrq_handle_SAK(int key, struct tty_struct *tty)
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2005-04-17 06:20:36 +08:00
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{
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2007-02-10 17:44:34 +08:00
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struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work;
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schedule_work(SAK_work);
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2005-04-17 06:20:36 +08:00
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}
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static struct sysrq_key_op sysrq_SAK_op = {
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.handler = sysrq_handle_SAK,
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.help_msg = "saK",
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.action_msg = "SAK",
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.enable_mask = SYSRQ_ENABLE_KEYBOARD,
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};
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2006-03-25 19:07:08 +08:00
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#else
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#define sysrq_SAK_op (*(struct sysrq_key_op *)0)
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2005-04-17 06:20:36 +08:00
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#endif
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#ifdef CONFIG_VT
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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 21:55:46 +08:00
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static void sysrq_handle_unraw(int key, struct tty_struct *tty)
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2005-04-17 06:20:36 +08:00
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{
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struct kbd_struct *kbd = &kbd_table[fg_console];
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if (kbd)
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2007-10-17 14:29:38 +08:00
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kbd->kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
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2005-04-17 06:20:36 +08:00
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}
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static struct sysrq_key_op sysrq_unraw_op = {
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.handler = sysrq_handle_unraw,
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.help_msg = "unRaw",
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2007-10-17 14:29:38 +08:00
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.action_msg = "Keyboard mode set to system default",
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2005-04-17 06:20:36 +08:00
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.enable_mask = SYSRQ_ENABLE_KEYBOARD,
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};
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2006-03-25 19:07:08 +08:00
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#else
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#define sysrq_unraw_op (*(struct sysrq_key_op *)0)
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2005-04-17 06:20:36 +08:00
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#endif /* CONFIG_VT */
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2009-06-18 07:28:17 +08:00
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|
|
static void sysrq_handle_crash(int key, struct tty_struct *tty)
|
2005-06-26 05:58:25 +08:00
|
|
|
{
|
2009-06-18 07:28:17 +08:00
|
|
|
char *killer = NULL;
|
sysrq, kdump: make sysrq-c consistent
commit d6580a9f15238b87e618310c862231ae3f352d2d ("kexec: sysrq: simplify
sysrq-c handler") changed the behavior of sysrq-c to unconditional
dereference of NULL pointer. So in cases with CONFIG_KEXEC, where
crash_kexec() was directly called from sysrq-c before, now it can be said
that a step of "real oops" was inserted before starting kdump.
However, in contrast to oops via SysRq-c from keyboard which results in
panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will
not become panic unless panic_on_oops=1. It means that even if dump is
properly configured to be taken on panic, the sysrq-c from proc interface
might not start crashdump while the sysrq-c from keyboard can start
crashdump. This confuses traditional users of kdump, i.e. people who
expect sysrq-c to do common behavior in both of the keyboard and proc
interface.
This patch brings the keyboard and proc interface behavior of sysrq-c in
line, by forcing panic_on_oops=1 before oops in sysrq-c handler.
And some updates in documentation are included, to clarify that there is
no longer dependency with CONFIG_KEXEC, and that now the system can just
crash by sysrq-c if no dump mechanism is configured.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Brayan Arraes <brayan@yack.com.br>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-30 06:04:14 +08:00
|
|
|
|
|
|
|
|
panic_on_oops = 1; /* force panic */
|
|
|
|
|
wmb();
|
2009-06-18 07:28:17 +08:00
|
|
|
*killer = 1;
|
2005-06-26 05:58:25 +08:00
|
|
|
}
|
sysrq, kdump: make sysrq-c consistent
commit d6580a9f15238b87e618310c862231ae3f352d2d ("kexec: sysrq: simplify
sysrq-c handler") changed the behavior of sysrq-c to unconditional
dereference of NULL pointer. So in cases with CONFIG_KEXEC, where
crash_kexec() was directly called from sysrq-c before, now it can be said
that a step of "real oops" was inserted before starting kdump.
However, in contrast to oops via SysRq-c from keyboard which results in
panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will
not become panic unless panic_on_oops=1. It means that even if dump is
properly configured to be taken on panic, the sysrq-c from proc interface
might not start crashdump while the sysrq-c from keyboard can start
crashdump. This confuses traditional users of kdump, i.e. people who
expect sysrq-c to do common behavior in both of the keyboard and proc
interface.
This patch brings the keyboard and proc interface behavior of sysrq-c in
line, by forcing panic_on_oops=1 before oops in sysrq-c handler.
And some updates in documentation are included, to clarify that there is
no longer dependency with CONFIG_KEXEC, and that now the system can just
crash by sysrq-c if no dump mechanism is configured.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Brayan Arraes <brayan@yack.com.br>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-30 06:04:14 +08:00
|
|
|
static struct sysrq_key_op sysrq_crash_op = {
|
2009-06-18 07:28:17 +08:00
|
|
|
.handler = sysrq_handle_crash,
|
|
|
|
|
.help_msg = "Crash",
|
|
|
|
|
.action_msg = "Trigger a crash",
|
2005-06-26 05:58:25 +08:00
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_reboot(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2006-10-01 14:28:02 +08:00
|
|
|
lockdep_off();
|
2005-04-17 06:20:36 +08:00
|
|
|
local_irq_enable();
|
2005-07-27 01:51:06 +08:00
|
|
|
emergency_restart();
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_reboot_op = {
|
|
|
|
|
.handler = sysrq_handle_reboot,
|
|
|
|
|
.help_msg = "reBoot",
|
|
|
|
|
.action_msg = "Resetting",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_BOOT,
|
|
|
|
|
};
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_sync(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
emergency_sync();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_sync_op = {
|
|
|
|
|
.handler = sysrq_handle_sync,
|
|
|
|
|
.help_msg = "Sync",
|
|
|
|
|
.action_msg = "Emergency Sync",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_SYNC,
|
|
|
|
|
};
|
|
|
|
|
|
2007-02-16 17:28:16 +08:00
|
|
|
static void sysrq_handle_show_timers(int key, struct tty_struct *tty)
|
|
|
|
|
{
|
|
|
|
|
sysrq_timer_list_show();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static struct sysrq_key_op sysrq_show_timers_op = {
|
|
|
|
|
.handler = sysrq_handle_show_timers,
|
|
|
|
|
.help_msg = "show-all-timers(Q)",
|
2008-10-20 18:33:14 +08:00
|
|
|
.action_msg = "Show clockevent devices & pending hrtimers (no others)",
|
2007-02-16 17:28:16 +08:00
|
|
|
};
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_mountro(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
emergency_remount();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_mountro_op = {
|
|
|
|
|
.handler = sysrq_handle_mountro,
|
|
|
|
|
.help_msg = "Unmount",
|
|
|
|
|
.action_msg = "Emergency Remount R/O",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_REMOUNT,
|
|
|
|
|
};
|
|
|
|
|
|
2006-07-03 15:24:56 +08:00
|
|
|
#ifdef CONFIG_LOCKDEP
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_showlocks(int key, struct tty_struct *tty)
|
2006-01-10 07:59:21 +08:00
|
|
|
{
|
2006-07-03 15:24:33 +08:00
|
|
|
debug_show_all_locks();
|
2006-01-10 07:59:21 +08:00
|
|
|
}
|
2006-07-03 15:24:56 +08:00
|
|
|
|
2006-01-10 07:59:21 +08:00
|
|
|
static struct sysrq_key_op sysrq_showlocks_op = {
|
|
|
|
|
.handler = sysrq_handle_showlocks,
|
|
|
|
|
.help_msg = "show-all-locks(D)",
|
|
|
|
|
.action_msg = "Show Locks Held",
|
|
|
|
|
};
|
2006-03-25 19:07:08 +08:00
|
|
|
#else
|
|
|
|
|
#define sysrq_showlocks_op (*(struct sysrq_key_op *)0)
|
2006-01-10 07:59:21 +08:00
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-04-29 15:59:21 +08:00
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
|
static DEFINE_SPINLOCK(show_lock);
|
|
|
|
|
|
|
|
|
|
static void showacpu(void *dummy)
|
|
|
|
|
{
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
/* Idle CPUs have no interesting backtrace. */
|
|
|
|
|
if (idle_cpu(smp_processor_id()))
|
|
|
|
|
return;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&show_lock, flags);
|
|
|
|
|
printk(KERN_INFO "CPU%d:\n", smp_processor_id());
|
|
|
|
|
show_stack(NULL, NULL);
|
|
|
|
|
spin_unlock_irqrestore(&show_lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void sysrq_showregs_othercpus(struct work_struct *dummy)
|
|
|
|
|
{
|
2008-06-27 17:52:45 +08:00
|
|
|
smp_call_function(showacpu, NULL, 0);
|
2008-04-29 15:59:21 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static DECLARE_WORK(sysrq_showallcpus, sysrq_showregs_othercpus);
|
|
|
|
|
|
|
|
|
|
static void sysrq_handle_showallcpus(int key, struct tty_struct *tty)
|
|
|
|
|
{
|
2009-08-03 15:31:54 +08:00
|
|
|
/*
|
|
|
|
|
* Fall back to the workqueue based printing if the
|
|
|
|
|
* backtrace printing did not succeed or the
|
|
|
|
|
* architecture has no support for it:
|
|
|
|
|
*/
|
|
|
|
|
if (!trigger_all_cpu_backtrace()) {
|
|
|
|
|
struct pt_regs *regs = get_irq_regs();
|
|
|
|
|
|
|
|
|
|
if (regs) {
|
|
|
|
|
printk(KERN_INFO "CPU%d:\n", smp_processor_id());
|
|
|
|
|
show_regs(regs);
|
|
|
|
|
}
|
|
|
|
|
schedule_work(&sysrq_showallcpus);
|
|
|
|
|
}
|
2008-04-29 15:59:21 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static struct sysrq_key_op sysrq_showallcpus_op = {
|
|
|
|
|
.handler = sysrq_handle_showallcpus,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "show-backtrace-all-active-cpus(L)",
|
2008-04-29 15:59:21 +08:00
|
|
|
.action_msg = "Show backtrace of all active CPUs",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
#endif
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_showregs(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
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 21:55:46 +08:00
|
|
|
struct pt_regs *regs = get_irq_regs();
|
|
|
|
|
if (regs)
|
|
|
|
|
show_regs(regs);
|
perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 18:02:48 +08:00
|
|
|
perf_event_print_debug();
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_showregs_op = {
|
|
|
|
|
.handler = sysrq_handle_showregs,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "show-registers(P)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Show Regs",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_showstate(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
show_state();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_showstate_op = {
|
|
|
|
|
.handler = sysrq_handle_showstate,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "show-task-states(T)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Show State",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
|
2006-12-07 12:35:59 +08:00
|
|
|
static void sysrq_handle_showstate_blocked(int key, struct tty_struct *tty)
|
|
|
|
|
{
|
|
|
|
|
show_state_filter(TASK_UNINTERRUPTIBLE);
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_showstate_blocked_op = {
|
|
|
|
|
.handler = sysrq_handle_showstate_blocked,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "show-blocked-tasks(W)",
|
2006-12-07 12:35:59 +08:00
|
|
|
.action_msg = "Show Blocked State",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
|
2008-11-02 02:53:34 +08:00
|
|
|
#ifdef CONFIG_TRACING
|
|
|
|
|
#include <linux/ftrace.h>
|
|
|
|
|
|
|
|
|
|
static void sysrq_ftrace_dump(int key, struct tty_struct *tty)
|
|
|
|
|
{
|
|
|
|
|
ftrace_dump();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_ftrace_dump_op = {
|
|
|
|
|
.handler = sysrq_ftrace_dump,
|
2008-12-25 08:06:57 +08:00
|
|
|
.help_msg = "dump-ftrace-buffer(Z)",
|
2008-11-02 02:53:34 +08:00
|
|
|
.action_msg = "Dump ftrace buffer",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
#else
|
|
|
|
|
#define sysrq_ftrace_dump_op (*(struct sysrq_key_op *)0)
|
|
|
|
|
#endif
|
2006-12-07 12:35:59 +08:00
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_showmem(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
show_mem();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_showmem_op = {
|
|
|
|
|
.handler = sysrq_handle_showmem,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "show-memory-usage(M)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Show Memory",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
|
|
|
};
|
|
|
|
|
|
2006-03-25 19:07:08 +08:00
|
|
|
/*
|
|
|
|
|
* Signal sysrq helper function. Sends a signal to all user processes.
|
|
|
|
|
*/
|
2005-04-17 06:20:36 +08:00
|
|
|
static void send_sig_all(int sig)
|
|
|
|
|
{
|
|
|
|
|
struct task_struct *p;
|
|
|
|
|
|
|
|
|
|
for_each_process(p) {
|
2007-10-19 14:39:52 +08:00
|
|
|
if (p->mm && !is_global_init(p))
|
2005-04-17 06:20:36 +08:00
|
|
|
/* Not swapper, init nor kernel thread */
|
|
|
|
|
force_sig(sig, p);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_term(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
send_sig_all(SIGTERM);
|
|
|
|
|
console_loglevel = 8;
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_term_op = {
|
|
|
|
|
.handler = sysrq_handle_term,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "terminate-all-tasks(E)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Terminate All Tasks",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
|
|
|
|
};
|
|
|
|
|
|
2006-11-22 22:55:48 +08:00
|
|
|
static void moom_callback(struct work_struct *ignored)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2009-12-16 08:45:33 +08:00
|
|
|
out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0, NULL);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
2006-11-22 22:55:48 +08:00
|
|
|
static DECLARE_WORK(moom_work, moom_callback);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_moom(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
schedule_work(&moom_work);
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_moom_op = {
|
|
|
|
|
.handler = sysrq_handle_moom,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "memory-full-oom-kill(F)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Manual OOM execution",
|
2008-10-16 13:01:43 +08:00
|
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
2005-04-17 06:20:36 +08:00
|
|
|
};
|
|
|
|
|
|
2009-04-01 06:23:46 +08:00
|
|
|
#ifdef CONFIG_BLOCK
|
|
|
|
|
static void sysrq_handle_thaw(int key, struct tty_struct *tty)
|
|
|
|
|
{
|
|
|
|
|
emergency_thaw_all();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_thaw_op = {
|
|
|
|
|
.handler = sysrq_handle_thaw,
|
|
|
|
|
.help_msg = "thaw-filesystems(J)",
|
|
|
|
|
.action_msg = "Emergency Thaw of all frozen filesystems",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
|
|
|
|
};
|
|
|
|
|
#endif
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_kill(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
send_sig_all(SIGKILL);
|
|
|
|
|
console_loglevel = 8;
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_kill_op = {
|
|
|
|
|
.handler = sysrq_handle_kill,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "kill-all-tasks(I)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Kill All Tasks",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
|
|
|
|
};
|
|
|
|
|
|
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 21:55:46 +08:00
|
|
|
static void sysrq_handle_unrt(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
normalize_rt_tasks();
|
|
|
|
|
}
|
|
|
|
|
static struct sysrq_key_op sysrq_unrt_op = {
|
|
|
|
|
.handler = sysrq_handle_unrt,
|
2009-01-07 06:41:13 +08:00
|
|
|
.help_msg = "nice-all-RT-tasks(N)",
|
2005-04-17 06:20:36 +08:00
|
|
|
.action_msg = "Nice All RT Tasks",
|
|
|
|
|
.enable_mask = SYSRQ_ENABLE_RTNICE,
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
/* Key Operations table and lock */
|
|
|
|
|
static DEFINE_SPINLOCK(sysrq_key_table_lock);
|
2006-03-25 19:07:08 +08:00
|
|
|
|
|
|
|
|
static struct sysrq_key_op *sysrq_key_table[36] = {
|
|
|
|
|
&sysrq_loglevel_op, /* 0 */
|
|
|
|
|
&sysrq_loglevel_op, /* 1 */
|
|
|
|
|
&sysrq_loglevel_op, /* 2 */
|
|
|
|
|
&sysrq_loglevel_op, /* 3 */
|
|
|
|
|
&sysrq_loglevel_op, /* 4 */
|
|
|
|
|
&sysrq_loglevel_op, /* 5 */
|
|
|
|
|
&sysrq_loglevel_op, /* 6 */
|
|
|
|
|
&sysrq_loglevel_op, /* 7 */
|
|
|
|
|
&sysrq_loglevel_op, /* 8 */
|
|
|
|
|
&sysrq_loglevel_op, /* 9 */
|
|
|
|
|
|
|
|
|
|
/*
|
2007-02-01 15:48:17 +08:00
|
|
|
* a: Don't use for system provided sysrqs, it is handled specially on
|
|
|
|
|
* sparc and will never arrive.
|
2006-03-25 19:07:08 +08:00
|
|
|
*/
|
|
|
|
|
NULL, /* a */
|
|
|
|
|
&sysrq_reboot_op, /* b */
|
sysrq, kdump: make sysrq-c consistent
commit d6580a9f15238b87e618310c862231ae3f352d2d ("kexec: sysrq: simplify
sysrq-c handler") changed the behavior of sysrq-c to unconditional
dereference of NULL pointer. So in cases with CONFIG_KEXEC, where
crash_kexec() was directly called from sysrq-c before, now it can be said
that a step of "real oops" was inserted before starting kdump.
However, in contrast to oops via SysRq-c from keyboard which results in
panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will
not become panic unless panic_on_oops=1. It means that even if dump is
properly configured to be taken on panic, the sysrq-c from proc interface
might not start crashdump while the sysrq-c from keyboard can start
crashdump. This confuses traditional users of kdump, i.e. people who
expect sysrq-c to do common behavior in both of the keyboard and proc
interface.
This patch brings the keyboard and proc interface behavior of sysrq-c in
line, by forcing panic_on_oops=1 before oops in sysrq-c handler.
And some updates in documentation are included, to clarify that there is
no longer dependency with CONFIG_KEXEC, and that now the system can just
crash by sysrq-c if no dump mechanism is configured.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Brayan Arraes <brayan@yack.com.br>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-30 06:04:14 +08:00
|
|
|
&sysrq_crash_op, /* c & ibm_emac driver debug */
|
2006-03-25 19:07:08 +08:00
|
|
|
&sysrq_showlocks_op, /* d */
|
|
|
|
|
&sysrq_term_op, /* e */
|
|
|
|
|
&sysrq_moom_op, /* f */
|
2009-05-14 10:56:59 +08:00
|
|
|
/* g: May be registered for the kernel debugger */
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* g */
|
2009-04-01 06:23:46 +08:00
|
|
|
NULL, /* h - reserved for help */
|
2006-03-25 19:07:08 +08:00
|
|
|
&sysrq_kill_op, /* i */
|
2009-04-01 06:23:46 +08:00
|
|
|
#ifdef CONFIG_BLOCK
|
|
|
|
|
&sysrq_thaw_op, /* j */
|
|
|
|
|
#else
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* j */
|
2009-04-01 06:23:46 +08:00
|
|
|
#endif
|
2006-03-25 19:07:08 +08:00
|
|
|
&sysrq_SAK_op, /* k */
|
2008-04-29 15:59:21 +08:00
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
|
&sysrq_showallcpus_op, /* l */
|
|
|
|
|
#else
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* l */
|
2008-04-29 15:59:21 +08:00
|
|
|
#endif
|
2006-03-25 19:07:08 +08:00
|
|
|
&sysrq_showmem_op, /* m */
|
|
|
|
|
&sysrq_unrt_op, /* n */
|
2007-02-01 15:48:17 +08:00
|
|
|
/* o: This will often be registered as 'Off' at init time */
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* o */
|
|
|
|
|
&sysrq_showregs_op, /* p */
|
2007-02-16 17:28:16 +08:00
|
|
|
&sysrq_show_timers_op, /* q */
|
2007-02-01 15:48:17 +08:00
|
|
|
&sysrq_unraw_op, /* r */
|
2006-03-25 19:07:08 +08:00
|
|
|
&sysrq_sync_op, /* s */
|
|
|
|
|
&sysrq_showstate_op, /* t */
|
|
|
|
|
&sysrq_mountro_op, /* u */
|
2009-05-14 10:56:59 +08:00
|
|
|
/* v: May be registered for frame buffer console restore */
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* v */
|
2007-02-01 15:48:17 +08:00
|
|
|
&sysrq_showstate_blocked_op, /* w */
|
|
|
|
|
/* x: May be registered on ppc/powerpc for xmon */
|
|
|
|
|
NULL, /* x */
|
2008-05-20 14:46:00 +08:00
|
|
|
/* y: May be registered on sparc64 for global register dump */
|
2006-03-25 19:07:08 +08:00
|
|
|
NULL, /* y */
|
2008-11-02 02:53:34 +08:00
|
|
|
&sysrq_ftrace_dump_op, /* z */
|
2005-04-17 06:20:36 +08:00
|
|
|
};
|
|
|
|
|
|
|
|
|
|
/* key2index calculation, -1 on invalid index */
|
2006-03-25 19:07:08 +08:00
|
|
|
static int sysrq_key_table_key2index(int key)
|
|
|
|
|
{
|
2005-04-17 06:20:36 +08:00
|
|
|
int retval;
|
2006-03-25 19:07:08 +08:00
|
|
|
|
|
|
|
|
if ((key >= '0') && (key <= '9'))
|
2005-04-17 06:20:36 +08:00
|
|
|
retval = key - '0';
|
2006-03-25 19:07:08 +08:00
|
|
|
else if ((key >= 'a') && (key <= 'z'))
|
2005-04-17 06:20:36 +08:00
|
|
|
retval = key + 10 - 'a';
|
2006-03-25 19:07:08 +08:00
|
|
|
else
|
2005-04-17 06:20:36 +08:00
|
|
|
retval = -1;
|
|
|
|
|
return retval;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* get and put functions for the table, exposed to modules.
|
|
|
|
|
*/
|
2006-03-25 19:07:08 +08:00
|
|
|
struct sysrq_key_op *__sysrq_get_key_op(int key)
|
|
|
|
|
{
|
|
|
|
|
struct sysrq_key_op *op_p = NULL;
|
2005-04-17 06:20:36 +08:00
|
|
|
int i;
|
2006-03-25 19:07:08 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
i = sysrq_key_table_key2index(key);
|
2006-03-25 19:07:08 +08:00
|
|
|
if (i != -1)
|
|
|
|
|
op_p = sysrq_key_table[i];
|
2005-04-17 06:20:36 +08:00
|
|
|
return op_p;
|
|
|
|
|
}
|
|
|
|
|
|
2006-03-25 19:07:08 +08:00
|
|
|
static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p)
|
|
|
|
|
{
|
|
|
|
|
int i = sysrq_key_table_key2index(key);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
if (i != -1)
|
|
|
|
|
sysrq_key_table[i] = op_p;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
2006-03-25 19:07:08 +08:00
|
|
|
* This is the non-locking version of handle_sysrq. It must/can only be called
|
|
|
|
|
* by sysrq key handlers, as they are inside of the lock
|
2005-04-17 06:20:36 +08:00
|
|
|
*/
|
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 21:55:46 +08:00
|
|
|
void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
|
struct sysrq_key_op *op_p;
|
|
|
|
|
int orig_log_level;
|
2006-03-25 19:07:08 +08:00
|
|
|
int i;
|
2005-04-17 06:20:36 +08:00
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&sysrq_key_table_lock, flags);
|
2009-01-16 05:50:52 +08:00
|
|
|
/*
|
|
|
|
|
* Raise the apparent loglevel to maximum so that the sysrq header
|
|
|
|
|
* is shown to provide the user with positive feedback. We do not
|
|
|
|
|
* simply emit this at KERN_EMERG as that would change message
|
|
|
|
|
* routing in the consumers of /proc/kmsg.
|
|
|
|
|
*/
|
2005-04-17 06:20:36 +08:00
|
|
|
orig_log_level = console_loglevel;
|
|
|
|
|
console_loglevel = 7;
|
|
|
|
|
printk(KERN_INFO "SysRq : ");
|
|
|
|
|
|
|
|
|
|
op_p = __sysrq_get_key_op(key);
|
|
|
|
|
if (op_p) {
|
2006-03-25 19:07:08 +08:00
|
|
|
/*
|
|
|
|
|
* Should we check for enabled operations (/proc/sysrq-trigger
|
|
|
|
|
* should not) and is the invoked operation enabled?
|
|
|
|
|
*/
|
2006-12-13 16:34:36 +08:00
|
|
|
if (!check_mask || sysrq_on_mask(op_p->enable_mask)) {
|
2006-03-25 19:07:08 +08:00
|
|
|
printk("%s\n", op_p->action_msg);
|
2005-04-17 06:20:36 +08:00
|
|
|
console_loglevel = orig_log_level;
|
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 21:55:46 +08:00
|
|
|
op_p->handler(key, tty);
|
2006-03-25 19:07:08 +08:00
|
|
|
} else {
|
2005-04-17 06:20:36 +08:00
|
|
|
printk("This sysrq operation is disabled.\n");
|
2006-03-25 19:07:08 +08:00
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
} else {
|
|
|
|
|
printk("HELP : ");
|
|
|
|
|
/* Only print the help msg once per handler */
|
2006-03-25 19:07:08 +08:00
|
|
|
for (i = 0; i < ARRAY_SIZE(sysrq_key_table); i++) {
|
|
|
|
|
if (sysrq_key_table[i]) {
|
|
|
|
|
int j;
|
|
|
|
|
|
|
|
|
|
for (j = 0; sysrq_key_table[i] !=
|
|
|
|
|
sysrq_key_table[j]; j++)
|
|
|
|
|
;
|
|
|
|
|
if (j != i)
|
|
|
|
|
continue;
|
|
|
|
|
printk("%s ", sysrq_key_table[i]->help_msg);
|
|
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2006-03-25 19:07:08 +08:00
|
|
|
printk("\n");
|
2005-04-17 06:20:36 +08:00
|
|
|
console_loglevel = orig_log_level;
|
|
|
|
|
}
|
|
|
|
|
spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* This function is called by the keyboard handler when SysRq is pressed
|
|
|
|
|
* and any other keycode arrives.
|
|
|
|
|
*/
|
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 21:55:46 +08:00
|
|
|
void handle_sysrq(int key, struct tty_struct *tty)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2006-12-13 16:34:36 +08:00
|
|
|
if (sysrq_on())
|
|
|
|
|
__handle_sysrq(key, tty, 1);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2006-03-25 19:07:08 +08:00
|
|
|
EXPORT_SYMBOL(handle_sysrq);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2005-11-09 13:39:47 +08:00
|
|
|
static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p,
|
2006-03-25 19:07:08 +08:00
|
|
|
struct sysrq_key_op *remove_op_p)
|
|
|
|
|
{
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
int retval;
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
|
|
spin_lock_irqsave(&sysrq_key_table_lock, flags);
|
|
|
|
|
if (__sysrq_get_key_op(key) == remove_op_p) {
|
|
|
|
|
__sysrq_put_key_op(key, insert_op_p);
|
|
|
|
|
retval = 0;
|
|
|
|
|
} else {
|
|
|
|
|
retval = -1;
|
|
|
|
|
}
|
|
|
|
|
spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
|
|
|
|
|
return retval;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int register_sysrq_key(int key, struct sysrq_key_op *op_p)
|
|
|
|
|
{
|
|
|
|
|
return __sysrq_swap_key_ops(key, op_p, NULL);
|
|
|
|
|
}
|
2006-03-25 19:07:08 +08:00
|
|
|
EXPORT_SYMBOL(register_sysrq_key);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
int unregister_sysrq_key(int key, struct sysrq_key_op *op_p)
|
|
|
|
|
{
|
|
|
|
|
return __sysrq_swap_key_ops(key, NULL, op_p);
|
|
|
|
|
}
|
|
|
|
|
EXPORT_SYMBOL(unregister_sysrq_key);
|
2008-10-16 13:04:23 +08:00
|
|
|
|
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
|
/*
|
|
|
|
|
* writing 'C' to /proc/sysrq-trigger is like sysrq-C
|
|
|
|
|
*/
|
|
|
|
|
static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
|
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
|
{
|
|
|
|
|
if (count) {
|
|
|
|
|
char c;
|
|
|
|
|
|
|
|
|
|
if (get_user(c, buf))
|
|
|
|
|
return -EFAULT;
|
|
|
|
|
__handle_sysrq(c, NULL, 0);
|
|
|
|
|
}
|
|
|
|
|
return count;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static const struct file_operations proc_sysrq_trigger_operations = {
|
|
|
|
|
.write = write_sysrq_trigger,
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
static int __init sysrq_init(void)
|
|
|
|
|
{
|
|
|
|
|
proc_create("sysrq-trigger", S_IWUSR, NULL, &proc_sysrq_trigger_operations);
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
module_init(sysrq_init);
|
|
|
|
|
#endif
|