In arch/ia64/kernel/ptrace.c there is a test for a peek or poke of a
register image (in register backing storage).
The test can be unnecessarily long (and occurs while holding the tasklist_lock).
Especially long on a large system with thousands of active tasks.
The ptrace caller (presumably a debugger) specifies the pid of
its target and an address to peek or poke. But the debugger could be
attached to several tasks.
The idea of find_thread_for_addr() is to find whether the target address
is in the RBS for any of those tasks.
Currently it searches the thread-list of the target pid. If that search
does not find a match, and the shared mm-struct's user count indicates
that there are other tasks sharing this address space (a rare occurrence),
a search is made of all the tasks in the system.
Another approach can drastically shorten this procedure.
It depends upon the fact that in order to peek or poke from/to any task,
the debugger must first attach to that task. And when it does, the
attached task is made a child of the debugger (is chained to its children list).
Therefore we can search just the debugger's children list.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In arch/ia64 change the explicit use of a for-loop using NR_CPUS into the
general for_each_online_cpu() construct. This widens the scope of potential
future optimizations of the general constructs, as well as takes advantage
of the existing optimizations of first_cpu() and next_cpu(), which is
advantageous when the true CPU count is much smaller than NR_CPUS.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In arch/ia64 change the explicit use of for-loops and NR_CPUS into the
general for_each_cpu() or for_each_online_cpu() constructs, as
appropriate. This widens the scope of potential future optimizations
of the general constructs, as well as takes advantage of the existing
optimizations of first_cpu() and next_cpu().
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The new ia64 assembler uses slot 1 for the offset of a long (2-slot)
instruction and the old assembler uses slot 2. The 2.6 kernel assumes
slot 2 and won't boot when the new assembler is used:
http://sources.redhat.com/bugzilla/show_bug.cgi?id=1433
This patch will work with either slot 1 or 2.
Patch provided by H.J. Lu
Signed-off-by: Tony Luck <tony.luck@intel.com>
Fix the "siblings" field value in /proc/cpuinfo so that it now shows the
number of siblings as seen by OS, instead of what is available from
hardware perspective.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
I've noticed a kernel hang during a storm of CMC interrupts, which was
tracked down to the continual execution of the interrupt handler.
There's code in the CMC handler that's supposed to disable CMC
interrupts and switch to polling mode when it sees a bunch of CMCs.
Because disabling CMCs across all CPUs isn't safe in interrupt context,
the disable is done with a schedule_work(). But with continual CMC
interrupts, the schedule_work() never gets executed.
The following patch immediately disables CMC interrupts for the current
CPU. This then allows (at least) one CPU to ignore CMC interrupts,
execute the schedule_work() code, and disable CMC interrupts on the rest
of the CPUs.
Acked-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Bryan Sutula <Bryan.Sutula@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
/proc/iomem describes a block of memory as "Kernel data",
but the end address is derived from "_edata". The kernel
actually has many other sections beyond _edata. Get the
real end address from _end.
Acked-by: Khalid Aziz <khalid_aziz@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Verify the pfn is valid before calling pfn_to_page(),
and cut isolation message if nothing was done.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Wire the MCA/INIT handler stacks into DTR[2] and track them in
IA64_KR(CURRENT_STACK). This gives the MCA/INIT handler stacks the
same TLB status as normal kernel stacks. Reload the old CURRENT_STACK
data on return from OS to SAL.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Move acpi_map_iosapics() from pci.c to acpi.c, since it doesn't
have anything to do with PCI.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Update comment about how ar.k0 is used. Make the initialization the
same as in start_secondary() (no functional change, just make it look
more similar).
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
User mode kexec tools expect to find information about physical
memory in /proc/iomem (as they do on x86) to validate the addresses
that the new kernel will use.
Signed-off-by: Khalid Aziz <khalid.aziz@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
With the new fdtable locking rules, you have to protect fdtable with either
->file_lock or rcu_read_lock/unlock(). There are some places where we
aren't doing either. This patch fixes those places.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There were some trailing white spaces, long lines, brackets in
weird style etc. This patch cleans them up.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch removes some compilation warnings, mostly
trivially. acpi.c fix also noted by Kenji Kaneshige.
Signed-off-by; Peter Chubb <peterc@gelato.unsw.edu.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Delete the special case unwind code that was only used by the old
MCA/INIT handler.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The bulk of the change. Use per cpu MCA/INIT stacks. Change the SAL
to OS state (sos) to be per process. Do all the assembler work on the
MCA/INIT stacks, leaving the original stack alone. Pass per cpu state
data to the C handlers for MCA and INIT, which also means changing the
mca_drv interfaces slightly. Lots of verification on whether the
original stack is usable before converting it to a sleeping process.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Reading the INIT record from SAL during the INIT event has proved to be
unreliable, and a source of hangs during INIT processing. The new
MCA/INIT handlers remove the need to get the INIT record from SAL.
Change salinfo.c so mca.c can just flag that a new record is available,
without having to read the record during INIT processing. This patch
can be applied without the new MCA/INIT handlers.
Also clean up some usage of NR_CPUS which should have been using
cpu_online().
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code. It does the following
things:
- consolidates and enhances the spinlock/rwlock debugging code
- simplifies the asm/spinlock.h files
- encapsulates the raw spinlock type and moves generic spinlock
features (such as ->break_lock) into the generic code.
- cleans up the spinlock code hierarchy to get rid of the spaghetti.
Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c. (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)
Also, i've enhanced the rwlock debugging facility, it will now track
write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.
The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:
include/asm-i386/spinlock_types.h | 16
include/asm-x86_64/spinlock_types.h | 16
I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:
SMP | UP
----------------------------|-----------------------------------
asm/spinlock_types_smp.h | linux/spinlock_types_up.h
linux/spinlock_types.h | linux/spinlock_types.h
asm/spinlock_smp.h | linux/spinlock_up.h
linux/spinlock_api_smp.h | linux/spinlock_api_up.h
linux/spinlock.h | linux/spinlock.h
/*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
All SMP and UP architectures are converted by this patch.
arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.
From: Grant Grundler <grundler@parisc-linux.org>
Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
Builds 32-bit SMP kernel (not booted or tested). I did not try to build
non-SMP kernels. That should be trivial to fix up later if necessary.
I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids
some ugly nesting of linux/*.h and asm/*.h files. Those particular locks
are well tested and contained entirely inside arch specific code. I do NOT
expect any new issues to arise with them.
If someone does ever need to use debug/metrics with them, then they will
need to unravel this hairball between spinlocks, atomic ops, and bit ops
that exist only because parisc has exactly one atomic instruction: LDCW
(load and clear word).
From: "Luck, Tony" <tony.luck@intel.com>
ia64 fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This converts the final 20 DEFINE_SPINLOCK holdouts. (another 580 places
are already using DEFINE_SPINLOCK). Build tested on x86.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically. Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure. This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct. It also changes all
the users to refer to the file table using files_fdtable() macro. Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
For architecture like ia64, the switch stack structure is fairly large
(currently 528 bytes). For context switch intensive application, we found
that significant amount of cache misses occurs in switch_to() function.
The following patch adds a hook in the schedule() function to prefetch
switch stack structure as soon as 'next' task is determined. This allows
maximum overlap in prefetch cache lines for that structure.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Delete obsolete stuff from arch Makefile
Rename file to asm-offsets.h
The trick used in the arch Makefile to circumvent the circular
dependency is kept.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
New version leaves the original memory map unmodified.
Also saves any granule trimmings for use by the uncached
memory allocator.
Inspired by Khalid Aziz (various traces of his patch still
remain). Fixes to uncached_build_memmap() and sn2 testing
by Martin Hicks.
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch fixes a race condition where in system used to hang or sometime
crash within minutes when kprobes are inserted on ISR routine and a task
routine.
The fix has been stress tested on i386, ia64, pp64 and on x86_64. To
reproduce the problem insert kprobes on schedule() and do_IRQ() functions
and you should see hang or system crash.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch addresses a potential race condition for a case where Kprobe has
been removed right after another CPU has taken a break hit.
The way this is addressed here is when the CPU that has taken a break hit
does not find its corresponding kprobe, then we check to see if the
original instruction got replaced with other than break. If it got
replaced with other than break instruction, then we continue to execute
from the replaced instruction, else if we find that it is still a break,
then we let the kernel handle this, as this might be the break instruction
inserted by other than kprobe(may be kernel debugger).
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch contains the ia64 architecture specific changes to prevent the
possible race conditions.
Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've already sent this to the maintainers, and this is now being sent to a
larger community audience. I have fixed a problem with the ia64 version of
build_sched_domains(), but a similar fix still needs to be made to the
generic build_sched_domains() in kernel/sched.c.
The "dynamic sched domains" functionality has recently been merged into
2.6.13-rcN that sees the dynamic declaration of a cpu-exclusive (a.k.a.
"isolated") cpuset and rebuilds the CPU Scheduler sched domains and sched
groups to separate away the CPUs in this cpu-exclusive cpuset from the
remainder of the non-isolated CPUs. This allows the non-isolated CPUs to
completely ignore the isolated CPUs when doing load-balancing.
Unfortunately, build_sched_domains() expects that a sched domain will
include all the CPUs of each node in the domain, i.e., that no node will
belong in both an isolated cpuset and a non-isolated cpuset. Declaring a
cpuset that violates this presumption will produce flawed data structures
and will oops the kernel.
To trigger the problem (on a NUMA system with >1 CPUs per node):
cd /dev/cpuset
mkdir newcpuset
cd newcpuset
echo 0 >cpus
echo 0 >mems
echo 1 >cpu_exclusive
I have fixed this shortcoming for ia64 NUMA (with multiple CPUs per node).
A similar shortcoming exists in the generic build_sched_domains() (in
kernel/sched.c) for NUMA, and that needs to be fixed also. The fix
involves dynamically allocating sched_group_nodes[] and
sched_group_allnodes[] for each invocation of build_sched_domains(), rather
than using global arrays for these structures. Care must be taken to
remember kmalloc() addresses so that arch_destroy_sched_domains() can
properly kfree() the new dynamic structures.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.
CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.
- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
when using generic irq framework.
Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.
MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch. Will test in a couple days.
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Acked-by: Zwane Mwaikambo <zwane@holomorphy.com>
Grudgingly-acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The config option 'CONFIG_ACPI_DEALLOCATE_IRQ' is no longer
needed. This patch removes it.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The reenabling of psr.ic should really belong to dtr mapping code block.
It make the fall through code fast since it doesn't need to execute the
predicated-off instruction. Logically make more sense as well since psr.ic
was turned off in .map code block.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Change sn2-specific calls into generic functions. Without this change
the uncached allocator will not work on non-sn2 platforms.
Signed-off-by: Greg Edwards <edwardsg@sgi.com>
Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Not all of the PAL VM calls are implemented for the SKI simulator.
Don't just give up if one fails, print information from the calls
that succeed.
Signed-off-by: Peter Chubb <peterc@gelato.unsw.edu.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>
