The Jazz machines have to use the PIT timer for dyntick and highresolution
kernels. This may break because currently just like i386 used to do MIPS
uses two separate spinlocks in the actual PIT code and the PC speaker
code. So switch to do it the same that x86 currently does PIT locking.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Do not include unnecessary headers.
* Do not mention time.README.
* Do not mention mips_timer_ack.
* Make clocksource_mips static. It is now dedicated to c0_timer.
* Initialize clocksource_mips.read statically.
* Remove null_hpt_read.
* Remove an argument of plat_timer_setup. It is just a placeholder.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
A comment on ptrace_getregs() states "Registers are sign extended to
fill the available space." but it is not true. Fix code to match the
comment. Also fix casts on each caller to get rid of some warnings.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Mmap with MAP_FIXED was not validating the addr and len parameters. This
leads to the failure of GCC's gcc.c-torture/execute/loop-2[fg].c testcases
when using the o32 ABI on a 64 bit kernel.
These testcases try to mmap 65536 bytes at 0x7fff8000 and then access all
the memory. In 2.6.18 and 2.6.23.1 (and likely other versions as well)
the kernel maps the requested memory, but since half of it is above
0x80000000 a SIGBUS is generated when it is accessed.
This patch moves the len validation above the MAP_FIXED processing so that
it is always validated. It also adds validation to the addr parameter for
MAP_FIXED mappings.
Signed-off-by: David Daney <ddaney@avtrex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Try increasingly longer time periods starting of at 0x10 cycles. This
should be fast on hardware and work nicely with emulators.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The expression "(long)(read_c0_count() - cnt)" can never be a negative
value on 64-bit kernel. Cast to "int" before comparison.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert jmr3927_clock_event_device to more generic
txx9tmr_clock_event_device which supports one-shot mode. The
txx9tmr_clock_event_device can be used for TX49 too if the cp0 timer
interrupt was not available.
Convert jmr3927_hpt_read to txx9_clocksource driver which does not
depends jiffies anymore. The txx9_clocksource itself can be used for
TX49, but normally TX49 uses higher precision clocksource_mips.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
clockevent_delta2ns() use the shift and mult value, so
clockevent_set_clock() should be called first.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
set_next_event() and set_mode() are always called with interrupt disabled.
irqsave and irqrestore are not necessary for spinlock.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the SMTC initialization code to allow boot-time specification not
only of how many VPEs and TCs to use, but also how many TCs out of the
allowed pool are to be bound to VPE 0. The new boot option is "vpe0tcs=N",
where N is an integer. Using it in combination with the existing options
allows arbitrary assignments across the 2 VPEs of a 34K. e.g. "maxtcs=3
vpe0tcs=1" forces VPE0 to have 1 TC, while VPE1 has 2, and "maxtcs=4
vpe0tcs=3" forces VPE0 to have 3 TCs, while VPE1 gets 1. If no vpe0tcs
option is specified, the traditional algorithm of evenly dividing TCs
between available VPEs, with the odd "slop" going to VPE0, is retained.
The reason for doing this is to allow a finer balancing of TCs which can
handle I/O interrupts on Malta (those on VPE 0) and those which cannot.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
And make use of it for Cobalt. A few others such as the Malta could make
use of it as well.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Delete totally outdated Documentation/mips/time.README
[MIPS] Kill duplicated setup_irq() for cp0 timer
[MIPS] Sibyte: Finish conversion to modern time APIs.
[MIPS] time: Helpers to compute clocksource/event shift and mult values.
[MIPS] SMTC: Build fix.
[MIPS] time: Delete dead code.
[MIPS] MIPSsim: Strip defconfig file to the bones.
One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.
It took some time to cross-compile it, but hopefully these are all the
printks in arch code.
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The set of functions process_session, task_session, process_group and
task_pgrp is confusing, as the names can be mixed with each other when looking
at the code for a long time.
The proposals are to
* equip the functions that return the integer with _nr suffix to
represent that fact,
* and to make all functions work with task (not process) by making
the common prefix of the same name.
For monotony the routines signal_session() and set_signal_session() are
replaced with task_session_nr() and set_task_session(), especially since they
are only used with the explicit task->signal dereference.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cycles_per_jiffy was only ever getting assigned and the function pointer
not being called anymore and mips_timer_ack had gotten similarly stale. I
leave the remaining assignments unfixed as a lighthouse pointing platform
maintainers to what needs a rewrite. These changes make null_timer_ack()
unreferenced, so delete that too.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Always jump to the place where the kernel is linked to. This helps where
the bootloaders/proms ignores the start address inside the ELF header.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some processors offer the option of using the interrupt on which
normally the count / compare interrupt would be signaled as a normal
interupt pin. Previously this required some ugly hackery for each
system which is much easier done by a quick and simple probe.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Userland, including the C library and the dynamic linker, is keen to use
the SYNC instruction, even for "generic" MIPS I binaries these days.
Which makes it less than useful on MIPS I processors.
This change adds the emulation, but as our do_ri() infrastructure was not
really prepared to take yet another instruction, I have rewritten it and
its callees slightly as follows.
Now there is only a single place a possible signal is thrown from. The
place is at the end of do_ri(). The instruction word is fetched in
do_ri() and passed down to handlers. The handlers are called in sequence
and return a result that lets the caller decide upon further processing.
If the result is positive, then the handler has picked the instruction,
but a signal should be thrown and the result is the signal number. If the
result is zero, then the handler has successfully simulated the
instruction. If the result is negative, then the handler did not handle
the instruction; to make it more obvious the calls do not follow the usual
0/-Exxx result convention they now return -1 instead of -EFAULT.
The calculation of the return EPC is now at the beginning. The reason is
it is easier to handle it there as emulation callees may modify a register
and an instruction may be located in delay slot of a branch whose result
depends on the register. It has to be undone if a signal is to be raised,
but it is not a problem as this is the slow-path case, and both actions
are done in single places now rather than the former being scattered
through emulation handlers.
The part of do_cpu() being covered follows the changes to do_ri().
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
All asm/ipc.h files do only #include <asm-generic/ipc.h>.
This patch therefore removes all include/asm-*/ipc.h files and moves the
contents of include/asm-generic/ipc.h to include/linux/ipc.h.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For some time /proc/sys/kernel/core_pattern has been able to set its output
destination as a pipe, allowing a user space helper to receive and
intellegently process a core. This infrastructure however has some
shortcommings which can be enhanced. Specifically:
1) The coredump code in the kernel should ignore RLIMIT_CORE limitation
when core_pattern is a pipe, since file system resources are not being
consumed in this case, unless the user application wishes to save the core,
at which point the app is restricted by usual file system limits and
restrictions.
2) The core_pattern code should be able to parse and pass options to the
user space helper as an argv array. The real core limit of the uid of the
crashing proces should also be passable to the user space helper (since it
is overridden to zero when called).
3) Some miscellaneous bugs need to be cleaned up (specifically the
recognition of a recursive core dump, should the user mode helper itself
crash. Also, the core dump code in the kernel should not wait for the user
mode helper to exit, since the same context is responsible for writing to
the pipe, and a read of the pipe by the user mode helper will result in a
deadlock.
This patch:
Remove the check of RLIMIT_CORE if core_pattern is a pipe. In the event that
core_pattern is a pipe, the entire core will be fed to the user mode helper.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Cc: <martin.pitt@ubuntu.com>
Cc: <wwoods@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Switch single-linked binfmt formats list to usual list_head's. This leads
to one-liners in register_binfmt() and unregister_binfmt(). The downside
is one pointer more in struct linux_binfmt. This is not a problem, since
the set of registered binfmts on typical box is very small -- (ELF +
something distro enabled for you).
Test-booted, played with executable .txt files, modprobe/rmmod binfmt_misc.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild: (40 commits)
kbuild: introduce ccflags-y, asflags-y and ldflags-y
kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP
kbuild: enable use of AFLAGS and CFLAGS on commandline
kbuild: enable 'make AFLAGS=...' to add additional options to AS
kbuild: fix AFLAGS use in h8300 and m68knommu
kbuild: check for wrong use of CFLAGS
kbuild: enable 'make CFLAGS=...' to add additional options to CC
kbuild: fix up CFLAGS usage
kbuild: make modpost detect unterminated device id lists
kbuild: call export_report from the Makefile
kbuild: move Kai Germaschewski to CREDITS
kconfig/menuconfig: distinguish between selected-by-another options and comments
kconfig: tristate choices with mixed tristate and boolean values
include/linux/Kbuild: remove duplicate entries
kbuild: kill backward compatibility checks
kbuild: kill EXTRA_ARFLAGS
kbuild: fix documentation in makefiles.txt
kbuild: call make once for all targets when O=.. is used
kbuild: pass -g to assembler under CONFIG_DEBUG_INFO
kbuild: update _shipped files for kconfig syntax cleanup
...
Fix up conflicts in arch/um/sys-{x86_64,i386}/Makefile manually.
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Increase cp0 compare clockevent min_delta_ns from 0x30 to 0x300.
[MIPS] Cache: Provide more information on cache policy on bootup.
[MIPS] Fix aliasing bug in copy_user_highpage, take 2.
[MIPS] VPE loader: convert from struct class_ device to struct device
[MIPS] MIPSsim: Fix booting from NFS root
[MIPS] Alchemy: Get rid of au1xxx_irq_map_t.
[MIPS] Alchemy: Get rid of au_ffz().
[MIPS] Alchemy: Get rid of au_ffs().
[MIPS] Alchemy: cleanup interrupt code.
[MIPS] Lasat: Fix build by conversion to irq_cpu.c.
[MIPS] Lasat: Add #ifndef ... #endif include warpper to lasatint.h.
[MIPS] IP22: Enable -Werror.
[MIPS] IP22: Fix warning.
[MIPS] IP22: Complain if requesting the front panel irq failed.
[MIPS] vmlinux.lds.S: Handle KPROBES_TEXT.
[MIPS] vmlinux.lds.S: Fix handling of .notes in final link.
[MIPS] vmlinux.lds.S: Remove duplicate comment.
[MIPS] MSP71XX: Add workarounds file.
[MIPS] IP32: Fix build by conversion to irq_cpu.c.
Extremly low values are of dubious usefulness anyway but in this case
they actually were killing Qemu which simply wasn't able to complete
mips_next_event() within 0x30 100MHz cycles even on fast hosts.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/sgi-ip22/ip22-berr.o
arch/mips/sgi-ip22/ip22-berr.c: In function 'ip22_be_interrupt':
arch/mips/sgi-ip22/ip22-berr.c💯 warning: passing argument 2 of 'die_if_kernel' discards qualifiers from pointer target type
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable CFLAGS is a wellknown variable and the usage by
kbuild may result in unexpected behaviour.
On top of that several people over time has asked for a way to
pass in additional flags to gcc.
This patch replace use of CFLAGS with KBUILD_CFLAGS all over the
tree and enabling one to use:
make CFLAGS=...
to specify additional gcc commandline options.
One usecase is when trying to find gcc bugs but other
use cases has been requested too.
Patch was tested on following architectures:
alpha, arm, i386, x86_64, mips, sparc, sparc64, ia64, m68k
Test was simple to do a defconfig build, apply the patch and check
that nothing got rebuild.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Loading ELF binaries based on the section table is totally wrong. This
still leaves the other fat bug of referencing symbols in an executable
unfixed, so people better don't run strip on their binaries ...
As added bonus the new loader is also 23 lines shorter.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
So far /proc/cpuinfo has been the only user but human readable processor
name are more useful than that for proc.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The kernel currently only supports broadcasting of the timer interrupt
from a single timer, not multicasting into two multicast groups of
processors. So the implemented mechanism for SMTC works by broadcasting
the cp0 compare interrupt on VPE 0 and ignoring it on any additional VPEs.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This replaces the MIPS-specific to_tm function with the generic
rtc_time_to_tm function. The big difference between the two functions is
that rtc_time_to_tm uses epoch 70 while to_tm uses 1970, so the result of
rtc_time_to_tm needs to be fixed up.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Hard to follow who is pointing what to where and why so it's simply getting
in the way of the time code renovation.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This has not been any serious user of this ill conceived thing since the
original invention in like '95.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
It may not be perfect yet but the SB1 code is badly borken and has
horrible performance issues.
Downside: This seriously breaks support for pass 1 parts of the BCM1250
where indexed cacheops don't work quite reliable but I seem to be the
last one on the planet with a pass 1 part anyway.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Match the R4000 semantics for the initial state of interrupt/kernel
status register flags for the R3000 in kernel_thread().
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This style will be consitent with all other arch's - soon.
In addition:
- Moved a few labels inside brackets for the sections they specify
to prevent that linker alignmnet made them point before the section start
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
o Move i8259 function declarations to include/asm-mips/i8259.h
o Make i8259.c functions static where possible.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Note that the BCM4710 does not support the wait instruction, this
is not a mistake in the code.
It originally comes from the OpenWrt patches.
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Felix Fietkau <nbd@openwrt.org>
Cc: Florian Schirmer <jolt@tuxbox.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Store any note sections after the exception tables like the other
architectures do. This is required for .note.gnu.build-id emitted from
binutils 2.18 onwards if nothing else.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS was mistakenly forgetting to use the fallocate compat wrapper, which
I noticed while cleaning up all the duplicate fallocate wrappers.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a workaround to address warnings generated on the "n" constraint by
GCC 3.3 and below.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Another issue with 20Kc's WAIT, waiting for more details. With the
2.6.23 release immindent simply disable the use of WAIT instead of a
more fancy workaround.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
It refer to CPU_PROFILING.
arch/mips/kernel/time.c: In function 'local_timer_interrupt':
arch/mips/kernel/time.c:142: error: implicit declaration of function 'profile_tick'
arch/mips/kernel/time.c:142: error: 'CPU_PROFILING' undeclared (first use in this function)
arch/mips/kernel/time.c:142: error: (Each undeclared identifier is reported only once
arch/mips/kernel/time.c:142: error: for each function it appears in.)
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/kernel/rtlx.o
cc1: warnings being treated as errors
arch/mips/kernel/rtlx.c:59: warning: 'irq' defined but not used
arch/mips/kernel/rtlx.c:60: warning: 'irq_num' defined but not used
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
CC arch/mips/kernel/rtlx.o
arch/mips/kernel/rtlx.c: In function 'rtlx_init':
arch/mips/kernel/rtlx.c:114: warning: format '%x' expects type 'unsigned int', but argument 3 has type 'long unsigned int'
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The appended patch adds code to update siginfo_t's si_code field. It
fixes e.g. a floating point overflow regression in the SBCL testsuite.
Signed-off-By: Thiemo Seufer <ths@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Also removes the while(1); loop by propagating the ATTRIB_NORET of die()
to nmi_exception_handler.
Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS doesn't do CPU hotplugging yet but since many of the functions don't
even have an __init let's fix this right.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Leaving these sections is useful to some tools that look at the image, and
none of them are loaded into memory. The .mdebug.abi64 section, in
particular, lets GDB recognize vmlinux.32 as an N64 program instead of
guessing that it is O32.
Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add generic irq_chip for TX39/TX49 SoCs. This can be replace
jmr3927_irq_irc, tx4927_irq_pic_type and tx4938_irq_pic_type.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In the other archs, there is more factoring of smp call code, and more care
in the use of get_cpu(). That can be a follow-up MIPS patch.
Signed-off-by: Peter Watkins <pwatkins@sicortex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/kernel/machine_kexec.c: In function 'machine_kexec':
arch/mips/kernel/machine_kexec.c:54: warning: assignment makes integer from pointer without a cast
arch/mips/kernel/machine_kexec.c:70: warning: assignment makes integer from pointer without a cast
arch/mips/kernel/machine_kexec.c:81: warning: format '%08x' expects type 'unsigned int', but argument 2 has type 'long unsigned int'
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch removes some duplicate includes from arch/mips/
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
__INIT directive just before kernel_entry was ignored for most platforms.
This patch fixes it and get rid of this warning:
WARNING: vmlinux.o(.text+0x478): Section mismatch: reference to .init.text:start_kernel (between '_stext' and 'run_init_process')
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Replaces the deprecated __attribute_used__ with __used. Also makes some
style adjustments to abide by the kernel coding conventions.
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
per cpu data section contains two types of data. One set which is
exclusively accessed by the local cpu and the other set which is per cpu,
but also shared by remote cpus. In the current kernel, these two sets are
not clearely separated out. This can potentially cause the same data
cacheline shared between the two sets of data, which will result in
unnecessary bouncing of the cacheline between cpus.
One way to fix the problem is to cacheline align the remotely accessed per
cpu data, both at the beginning and at the end. Because of the padding at
both ends, this will likely cause some memory wastage and also the
interface to achieve this is not clean.
This patch:
Moves the remotely accessed per cpu data (which is currently marked
as ____cacheline_aligned_in_smp) into a different section, where all the data
elements are cacheline aligned. And as such, this differentiates the local
only data and remotely accessed data cleanly.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Identical implementations of PTRACE_POKEDATA go into generic_ptrace_pokedata()
function.
AFAICS, fix bug on xtensa where successful PTRACE_POKEDATA will nevertheless
return EPERM.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the kernel OOPSed or BUGed then it probably should be considered as
tainted. Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel. This saves a lot of time explaining oddities in the
calltraces.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Added parisc patch from Matthew Wilson -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While the PC speaker is wired up to the i8254 there is more to the i8254
than just the PC speaker so this code was getting in the way under its
current name.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
To support multiple TC microthreads acting as "CPUs" within a VPE,
VPE-wide interrupt mask bits must be specially manipulated during
interrupt handling. To support legacy drivers and interrupt controller
management code, SMTC has a "backstop" to track and if necessary restore
the interrupt mask. This has some performance impact on interrupt service
overhead. Disable it only if you know what you are doing.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Currently a number of unaligned instructions is counted but not used.
Add /debug/mips/unaligned_instructions file to show the value.
And add /debug/mips/unaligned_action to control behavior upon an
unaligned access. Possible actions are:
0: silently fixup the unaligned access.
1: send SIGBUS.
2: dump registers, process name, etc. and fixup.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patch to add mips common support for the PMC-Sierra MSP71xx devices.
Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Which will cut down the cost of RDHWR $29 which is used to obtain the
TLS pointer and so far being emulated in software down to a single cycle
operation.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert old/obsolete NORET_TYPE and ATTRIB_NORET macros to use the
newer standard of "__noreturn" as defined in compiler-gcc.h.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
the SMP load-balancer uses the boot-time migration-cost estimation
code to attempt to improve the quality of balancing. The reason for
this code is that the discrete priority queues do not preserve
the order of scheduling accurately, so the load-balancer skips
tasks that were running on a CPU 'recently'.
this code is fundamental fragile: the boot-time migration cost detector
doesnt really work on systems that had large L3 caches, it caused boot
delays on large systems and the whole cache-hot concept made the
balancing code pretty undeterministic as well.
(and hey, i wrote most of it, so i can say it out loud that it sucks ;-)
under CFS the same purpose of cache affinity can be achieved without
any special cache-hot special-case: tasks are sorted in the 'timeline'
tree and the SMP balancer picks tasks from the left side of the
tree, thus the most cache-cold task is balanced automatically.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The idle loop goes to sleep using the WAIT instruction if !need_resched().
This has is suffering from from a race condition that if if just after
need_resched has returned 0 an interrupt might set TIF_NEED_RESCHED but
we've just completed the test so go to sleep anyway. This would be
trivial to fix by just disabling interrupts during that sequence as in:
local_irq_disable();
if (!need_resched())
__asm__("wait");
local_irq_enable();
but the processor architecture leaves it undefined if a processor calling
WAIT with interrupts disabled will ever restart its pipeline and indeed
some processors have made use of the freedom provided by the architecture
definition. This has been resolved and the Config7.WII bit indicates that
the use of WAIT is safe on 24K, 24KE and 34K cores. It also is safe on
74K starting revision 2.1.0 so enable the use of WAIT with interrupts
disabled for 74K based on a c0_prid of at least that.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
C0_status doesn't need to be initialized at this point anyway; the register
will be initialized later.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
