Right now if we want to busy loop and not give up any time to the hypervisor
we put a very large value into smt_snooze_delay. This is sometimes useful
when running a single partition and you want to avoid any latencies due
to the hypervisor or CPU power state transitions. While this works, it's a bit
ugly - how big a number is enough now we have NO_HZ and can be idle for a very
long time.
The patch below makes smt_snooze_delay signed, and a negative value means loop
forever:
echo -1 > /sys/devices/system/cpu/cpu0/smt_snooze_delay
This change shouldn't affect the existing userspace tools (eg ppc64_cpu), but
I'm cc-ing Nathan just to be sure.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
I'm not sure why we have code for parsing an ibm,smt-snooze-delay OF
property. Since we have a smt-snooze-delay= boot option and we can
also set it at runtime via sysfs, it should be safe to get rid of
this code.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Version 3 of this patch is updated with documentation added to
Documentation/ABI. There are no changes to any of the C code from v2
of the patch.
In order to support kernel DLPAR of CPU resources we need to provide an
interface to add (probe) and remove (release) the resource from the system.
This patch Creates new generic probe and release sysfs files to facilitate
cpu probe/release. The probe/release interface provides for allowing each
arch to supply their own routines for implementing the backend of adding
and removing cpus to/from the system.
This also creates the powerpc specific stubs to handle the arch callouts
from writes to the sysfs files.
The creation and use of these files is regulated by the
CONFIG_ARCH_CPU_PROBE_RELEASE option so that only architectures that need the
capability will have the files created.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently there is a bug where if you use oprofile on a pSeries
machine, then use perf_counters, then use oprofile again, oprofile
will not work correctly; it will lose the PMU configuration the next
time the hypervisor does a partition context switch, and thereafter
won't count anything.
Maynard Johnson identified the sequence causing the problem:
- oprofile setup calls ppc_enable_pmcs(), which calls
pseries_lpar_enable_pmcs, which tells the hypervisor that we want
to use the PMU, and sets the "PMU in use" flag in the lppaca.
This flag tells the hypervisor whether it needs to save and restore
the PMU config.
- The perf_counter code sets and clears the "PMU in use" flag directly
as it context-switches the PMU between tasks, and leaves it clear
when it finishes.
- oprofile setup, called for a new oprofile run, calls ppc_enable_pmcs,
which does nothing because it has already been called. In particular
it doesn't set the "PMU in use" flag.
This fixes the problem by arranging for ppc_enable_pmcs to always set
the "PMU in use" flag. It makes the perf_counter code call
ppc_enable_pmcs also rather than calling the lower-level function
directly, and removes the setting of the "PMU in use" flag from
pseries_lpar_enable_pmcs, since that is now done in its caller.
This also removes the declaration of pasemi_enable_pmcs because it
isn't defined anywhere.
Reported-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: <stable@kernel.org)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rusty's patch to change our sysfs access to various registers
to use smp_call_function_single() introduced a whole bunch of
warnings. This fixes them. This version also fixes an actual
bug in here where it did mtspr instead of mfspr when reading
the files
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Impact: performance improvement
This fixes 'powerpc: avoid cpumask games in arch/powerpc/kernel/sysfs.c'
which talked about using smp_call_function_single, but actually used
work_on_cpu (an older version of the patch).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current code for providing processor cache information in sysfs
has the following deficiencies:
- several complex functions that are hard to understand
- implicit recursion (cache_desc_release -> kobject_put -> cache_desc_release)
- explicit recursion (create_cache_index_info)
- use of two per-cpu arrays when one would suffice
- duplication of work on systems where CPUs share cache
Also, when I looked at implementing support for a shared_cpu_map
attribute, it was pretty much impossible to handle hotplug without
checking every single online CPU's cache_desc list and fixing things
up... not that this is a hot path, but it would have introduced
O(n^2)-ish behavior during boot. Addressing this involved rethinking
the core data structures used, which didn't lend itself to an
incremental approach.
This implementation maintains a "forest" (potentially more than one
tree) of cache objects which reflects the system's cache topology.
Cache objects are instantiated as needed as CPUs come online. A
per-cpu array is used mainly for sysfs-related bookkeeping; the
objects in the array just point to the appropriate points in the
forest.
This maintains compatibility with the existing code and includes some
enhancements:
- Implement the shared_cpu_map attribute, which is essential for
enabling userspace to discover the system's overall cache topology.
- Use cache-block-size properties if cache-line-size is not available.
I chose to place this implementation in a new file since it would have
roughly doubled the size of sysfs.c, which is already kind of messy.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Using the common code means that more complete cache information will
provided in sysfs on platforms that don't use the l2-cache property
convention.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
attr_smt_snooze_delay is only defined for CONFIG_PPC64, so protect the
attribute removal with the same condition. This fixes this build error
on 32-bit SMP configurations:
/data/home/miltonm/next.git/arch/powerpc/kernel/sysfs.c: In function ‘unregister_cpu_online’:
/data/home/miltonm/next.git/arch/powerpc/kernel/sysfs.c:722: error: ‘attr_smt_snooze_delay’ undeclared (first use in this function)
/data/home/miltonm/next.git/arch/powerpc/kernel/sysfs.c:722: error: (Each undeclared identifier is reported only once
/data/home/miltonm/next.git/arch/powerpc/kernel/sysfs.c:722: error: for each function it appears in.)
Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/kernel/sysfs.c:197:7: warning: "CONFIG_6xx" is not defined
arch/powerpc/kernel/sysfs.c:141: warning: 'run_on_cpu' defined but not used
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The file arch/powerpc/kernel/sysfs.c is currently only compiled for
64-bit kernels. It contain code to register CPU sysdevs in sysfs and
add various properties such as cache topology and raw access by root
to performance monitor counters (PMCs). A lot of that can be re-used
as is on 32-bits.
This makes the file be built for both, with appropriate ifdef'ing
for the few bits that are really 64-bit specific, and adds some
support for the raw PMCs for 75x and 74xx processors.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When removing a directory, the sysfs core takes care of removing files
in the directory (see sysfs_remove_dir()). So when we are about to
delete a kobject (and thus cause its sysfs directory to be removed),
we don't have to explicitly remove the files attached to it, although
it's harmless to do so.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Collect cache information from the OF device tree and display it in
the cpu hierarchy in sysfs. This is intended to be compatible at the
userspace level with x86's implementation[1], hence some of the funny
attribute names. The arrangement of cache info is not immediately
intuitive, but (again) it's for compatibility's sake.
The cache attributes exposed are:
type (Data, Instruction, or Unified)
level (1, 2, 3...)
size
coherency_line_size
number_of_sets
ways_of_associativity
All of these can be derived on platforms that follow the OF PowerPC
Processor binding. The code "publishes" only those attributes for
which it is able to determine values; attributes for values which
cannot be determined are not created at all.
[1] arch/x86/kernel/cpu/intel_cacheinfo.c
BenH: Turned some printk's into pr_debug, added better NULL checking
in a couple of places.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It is called only in cpu online paths.
(caught by CONFIG_DEBUG_SECTION_MISMATCH=y)
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
A struct sysdev_attribute * parameter was added to the show routine by
commit 4a0b2b4dbe "sysdev: Pass the
attribute to the low level sysdev show/store function".
This eliminates a warning:
arch/powerpc/kernel/sysfs.c:538: warning: initialization from incompatible pointer type
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.
I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.
I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.
Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove the deprecated __attribute_used__.
[Introduce __section in a few places to silence checkpatch /sam]
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Fixes:
arch/powerpc/kernel/sysfs.c: In function 'cpu_add_sysdev_attr_group':
arch/powerpc/kernel/sysfs.c:388: warning: ignoring return value of
'sysfs_create_group', declared with attribute warn_unused_result
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Export some of the implementation-specific registers via sysfs.
Useful when debugging, etc.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
With !CONFIG_NUMA, these are static inlines in the header file so
don't generate exports for them in that case.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress. This
patch introduces such notifications and causes them to be used during
suspend and resume transitions. It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).
[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the powerpc version of topology_init() from an __initcall to
a subsys_initcall to match all other architectures.
Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Oprofile support for PA6T, kernel side.
Also rename the PA6T_SPRN.* defines to SPRN_PA6T.*.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Support for PA6T-style PMC registers.
PMCs are completely implementation-dependent on PPC, and PA6T numbers them
differently from the IBM model.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now we have a SPURR cpu feature bit, we can export it to userspace in
sysfs.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
POWER6 adds a new SPR, the data stream control register (DSCR). It can
be used to adjust how agressive the prefetch mechanisms are.
Its possible we may want to context switch this, but for now just export
it to userspace via sysfs so we can adjust it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Change the 'no_control' field in the cpu struct to a more positive
and better term 'hotpluggable'. And change(/cleanup) the logic accordingly.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: "Li, Shaohua" <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
This patch adds two functions to create and remove sysfs attributes and
attribute_group to all cpus. That allows to register sysfs attributes in
a subdirectory like: /sys/devices/system/cpu/cpuX/group_name/what_ever
This will be used by cbe_thermal to group all attributes dealing with
thermal support in one directory.
Signed-of-by: Christian Krafft <krafft@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The smt_snooze_delay logic changed a bit when the idle loops were
consolidated. A value of 0 used to mean we always polled, now it means
we always sleep. Instead of restoring the old behaviour, lets put a
reasonable default in smt_snooze_delay. This means we spin for a bit
(in case an external interrupt comes in) and then sleep.
Also the pseries dedicated idle loop currently does not cede both
threads in an SMT pair. The hypervisor wants us to call in so it can
power manage, so lets do that.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Few of the callback functions and notifier blocks that are associated with cpu
notifications incorrectly have __devinit and __devinitdata. They should be
__cpuinit and __cpuinitdata instead.
It makes no functional difference but wastes text area when CONFIG_HOTPLUG is
enabled and CONFIG_HOTPLUG_CPU is not.
This patch fixes all those instances.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Now that get_property() returns a void *, there's no need to cast its
return value. Also, treat the return value as const, so we can
constify get_property later.
powerpc core changes.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In 2.6.17, there was a problem with cpu_notifiers and XFS. I provided a
band-aid solution to solve that problem. In the process, i undid all the
changes you both were making to ensure that these notifiers were available
only at init time (unless CONFIG_HOTPLUG_CPU is defined).
We deferred the real fix to 2.6.18. Here is a set of patches that fixes the
XFS problem cleanly and makes the cpu notifiers available only at init time
(unless CONFIG_HOTPLUG_CPU is defined).
If CONFIG_HOTPLUG_CPU is defined then cpu notifiers are available at run
time.
This patch reverts the notifier_call changes made in 2.6.17
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With Goto-san's patch, we can add new pgdat/node at runtime. I'm now
considering node-hot-add with cpu + memory on ACPI.
I found acpi container, which describes node, could evaluate cpu before
memory. This means cpu-hot-add occurs before memory hot add.
In most part, cpu-hot-add doesn't depend on node hot add. But register_cpu(),
which creates symbolic link from node to cpu, requires that node should be
onlined before register_cpu(). When a node is onlined, its pgdat should be
there.
This patch-set holds off creating symbolic link from node to cpu
until node is onlined.
This removes node arguments from register_cpu().
Now, register_cpu() requires 'struct node' as its argument. But the array of
struct node is now unified in driver/base/node.c now (By Goto's node hotplug
patch). We can get struct node in generic way. So, this argument is not
necessary now.
This patch also guarantees add cpu under node only when node is onlined. It
is necessary for node-hot-add vs. cpu-hot-add patch following this.
Moreover, register_cpu calculates cpu->node_id by cpu_to_node() without regard
to its 'struct node *root' argument. This patch removes it.
Also modify callers of register_cpu()/unregister_cpu, whose args are changed
by register-cpu-remove-node-struct patch.
[Brice.Goglin@ens-lyon.org: fix it]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Brice Goglin <Brice.Goglin@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When new node becomes enable by hot-add, new sysfs file must be created for
new node. So, if new node is enabled by add_memory(), register_one_node() is
called to create it. In addition, I386's arch_register_node() and a part of
register_nodes() of powerpc are consolidated to register_one_node() as a
generic_code().
This is tested by Tiger4(IPF) with node hot-plug emulation.
Signed-off-by: Keiichiro Tokunaga <tokuanga.keiich@jp.fujitsu.com>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change of_node_to_nid() to traverse the device tree, looking for a numa id.
Cell uses this to assign ids to SPUs, which are children of the CPU node.
Existing users of of_node_to_nid() are altered to use of_node_to_nid_single(),
which doesn't do the traversal.
Export an attach_sysdev_to_node() function, allowing system devices (eg.
SPUs) to link themselves into the numa topology in sysfs.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Few of the notifier_chain_register() callers use __init in the definition
of notifier_call. It is incorrect as the function definition should be
available after the initializations (they do not unregister them during
initializations).
This patch fixes all such usages to _not_ have the notifier_call __init
section.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Few of the notifier_chain_register() callers use __devinitdata in the
definition of notifier_block data structure. It is incorrect as the
data structure should be available after the initializations (they do
not unregister them during initializations).
This was leading to an oops when notifier_chain_register() call is
invoked for those callback chains after initialization.
This patch fixes all such usages to _not_ have the notifier_block data
structure in the init data section.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Non zero initcalls (except for -ENODEV) have started warning at boot.
Fix smt_setup and init_ras_IRQ.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch moves the vdso's to arch/powerpc, adds support for the 32
bits vdso to the 32 bits kernel, rename systemcfg (finally !), and adds
some new (still untested) routines to both vdso's: clock_gettime() with
support for CLOCK_REALTIME and CLOCK_MONOTONIC, clock_getres() (same
clocks) and get_tbfreq() for glibc to retreive the timebase frequency.
Tom,Steve: The implementation of get_tbfreq() I've done for 32 bits
returns a long long (r3, r4) not a long. This is such that if we ever
add support for >4Ghz timebases on ppc32, the userland interface won't
have to change.
I have tested gettimeofday() using some glibc patches in both ppc32 and
ppc64 kernels using 32 bits userland (I haven't had a chance to test a
64 bits userland yet, but the implementation didn't change and was
tested earlier). I haven't tested yet the new functions.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch moves a bunch more files from arch/ppc64 and
include/asm-ppc64 which have no equivalents in ppc32 code into
arch/powerpc and include/asm-powerpc. The file affected are:
hvcall.h
proc_ppc64.c
sysfs.c
lparcfg.c
rtas_pci.c
The only changes apart from the move and corresponding Makefile
changes are:
- #ifndef/#define in includes updated to _ASM_POWERPC_ form
- trailing whitespace removed
- comments giving full paths removed
Built and booted on POWER5 LPAR (ARCH=powerpc and ARCH=ppc64), built
for 32-bit powermac (ARCH=powerpc).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
