The ptrace_get_task_struct() helper that I added as part of the ptrace
consolidation is useful in variety of places that currently opencode it.
Switch them to the common helpers.
Add a ptrace_traceme() helper that needs to be explicitly called, and simplify
the ptrace_get_task_struct() interface. We don't need the request argument
now, and we return the task_struct directly, using ERR_PTR() for error
returns. It's a bit more code in the callers, but we have two sane routines
that do one thing well now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sys_migrate_pages implementation using swap based page migration
This is the original API proposed by Ray Bryant in his posts during the first
half of 2005 on linux-mm@kvack.org and linux-kernel@vger.kernel.org.
The intent of sys_migrate is to migrate memory of a process. A process may
have migrated to another node. Memory was allocated optimally for the prior
context. sys_migrate_pages allows to shift the memory to the new node.
sys_migrate_pages is also useful if the processes available memory nodes have
changed through cpuset operations to manually move the processes memory. Paul
Jackson is working on an automated mechanism that will allow an automatic
migration if the cpuset of a process is changed. However, a user may decide
to manually control the migration.
This implementation is put into the policy layer since it uses concepts and
functions that are also needed for mbind and friends. The patch also provides
a do_migrate_pages function that may be useful for cpusets to automatically
move memory. sys_migrate_pages does not modify policies in contrast to Ray's
implementation.
The current code here is based on the swap based page migration capability and
thus is not able to preserve the physical layout relative to it containing
nodeset (which may be a cpuset). When direct page migration becomes available
then the implementation needs to be changed to do a isomorphic move of pages
between different nodesets. The current implementation simply evicts all
pages in source nodeset that are not in the target nodeset.
Patch supports ia64, i386 and x86_64.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
arch/ia64/kernel/setup.c: In function `show_cpuinfo':
arch/ia64/kernel/setup.c:576: warning: long unsigned int format, different type arg (arg 12)
arch/ia64/kernel/setup.c:576: warning: long unsigned int format, different type arg (arg 13)
Introduced by 95235ca2c2
Signed-off-by: Tony Luck <tony.luck@intel.com>
The first of these changes s/hotplug/uevent/ was needed to
compile sn2_defconfig (ia64/sn). The other three files
changed are blind changes of all remaining bus_type.hotplug
references I could find to bus_type.uevent.
This patch attempts to finish similar changes made in the
gregkh-driver-kill-hotplug-word-from-driver-core Nov 22 patch.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The function ia64_pci_legacy_write() returns 0 for everything
except errors. This return value gets sent back to the user from
pci_write_legacy_io(), making it look like every write fails. The trivial
patch below copies the behavior of the SGI sn machvec and does what
would be expected from something implementing a write() function.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
sparc64, i386 and x86_64 have support for a special data section dedicated
to rarely updated data that is frequently read. The section was created to
avoid false sharing of those rarely read data with frequently written kernel
data.
This patch creates such a data section for ia64 and will group rarely written
data into this section.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Change the NR_CPUS default for ia64/sn up to 1024.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: John Hesterberg <jh@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
I see why the problem exists only on SN. SN uses a different hardware
mechanism to purge TLB entries across nodes.
It looks like there is a bug in the SN TLB flushing code. During context switch,
kernel threads inherit the mm of the task that was previously running on the
cpu. This confuses the code in sn2_global_tlb_purge().
The result is a missed TLB purge for the task that owns the "borrowed" mm.
(I hit the problem running heavy stress where kswapd was purging code pages of
a user task that woke kswapd. The user task took a SIGILL fault trying to
execute code in the page that had been ripped out from underneath it).
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Use raw_smp_processor_id() instead of get_cpu() as we don't need the
extra features of get_cpu().
Signed-off-by: Jes Sorensen <jes@trained-monkey.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The udelay() inline for ia64 uses the ITC. If CONFIG_PREEMPT is enabled
and the platform has unsynchronized ITCs and the calling task migrates
to another CPU while doing the udelay loop, then the effective delay may
be too short or very, very long.
This patch disables preemption around 100 usec chunks of the overall
desired udelay time. This minimizes preemption-holdoffs.
udelay() is now too big to be inline, move it out of line and export it.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
I realized ZONE_DMA32 has a trivial bug at Kconfig for ia64. In
include/linux/gfp.h on 2.6.15-rc5-mm1, CONFIG is define like followings.
#ifdef CONFIG_DMA_IS_DMA32
#define __GFP_DMA32 ((__force gfp_t)0x01) /* ZONE_DMA is ZONE_DMA32
*/
:
:
So, CONFIG_"ZONE"_DMA_IS_DMA32 is clearly wrong.
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When multiple probes are registered at the same address and if due to some
recursion (probe getting triggered within a probe handler), we skip calling
pre_handlers and just increment nmissed field.
The below patch make sure it walks the list for multiple probes case.
Without the below patch we get incorrect results of nmissed count for
multiple probe case.
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>
What is the value shown in "cpu MHz" of /proc/cpuinfo when CPUs are capable of
changing frequency?
Today the answer is: It depends.
On i386:
SMP kernel - It is always the boot frequency
UP kernel - Scales with the frequency change and shows that was last set.
On x86_64:
There is one single variable cpu_khz that gets written by all the CPUs. So,
the frequency set by last CPU will be seen on /proc/cpuinfo of all the
CPUs in the system. What you see also depends on whether you have constant_tsc
capable CPU or not.
On ia64:
It is always boot time frequency of a particular CPU that gets displayed.
The patch below changes this to:
Show the last known frequency of the particular CPU, when cpufreq is present. If
cpu doesnot support changing of frequency through cpufreq, then boot frequency
will be shown. The patch affects i386, x86_64 and ia64 architectures.
Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
The patch that added support for a new platform chipset (shub2) broke
PTC deadlock recovery on older versions of the chipset. (PTCs are the
SN platform-specific method for doing a global TLB purge). This
patch fixes deadlock recovery so that it works on both the old & new
chipsets.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
We have a customer application which trips a bug. The problem arises
when a driver attempts to call do_munmap on an area which is mapped, but
because current->thread.task_size has been set to 0xC0000000, the call
to do_munmap fails thinking it is an unmap beyond the user's address
space.
The comment in fs/binfmt_elf.c in load_elf_library() before the call
to SET_PERSONALITY() indicates that task_size must not be changed for
the running application until flush_thread, but is for ia64 executing
ia32 binaries.
This patch moves the setting of task_size from SET_PERSONALITY() to
flush_thread() as indicated. The customer application no longer is able
to trip the bug.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The per-node data structures are allocated with strided offsets that are a
function of the node number. This prevents excessive cache-aliasing from
occurring.
On systems with a large number of nodes, the strided offset becomes
too large. This patch restricts the maximum offset to 32MB. This is far larger
than the size of any current L3 cache.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Altix only patch to add fixup code that sets up
pci_controller->window. This code is a temporary
fix until ACPI support on Altix is added.
Also, corrects the usage of pci_dev->sysdata,
which had previously been used to reference
platform specific device info, to now point to
a pci_controller struct.
Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Return -EINTR instead of -ERESTARTSYS when signals are delivered during
a blocked read of /proc/sal/*/event. This allows salinfo_decode to
detect signals when it is blocked on a read of those files.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Christoph Hellwig
Christoph Lameter
Tony Luck
Linus Torvalds
Paul Jackson
Alex Williamson
Christoph Lameter
hawkes@sgi.com
Jack Steiner
Jes Sorensen
Al Viro
Robin Holt
Yasunori Goto
Keshavamurthy Anil S
Venkatesh Pallipadi
John Keller
Keith Owens