linux-toradex.git/drivers/base/topology.c, branch v4.9-rc3

topology/sysfs: provide drawer id and siblings attributes

2016-06-13T13:58:27+00:00

The s390 cpu topology gained another hierarchy level. The top level is
now called drawer and contains several books. A book used to be the
top level.

In order to expose the cpu topology to user space allow to create new
sysfs attributes dependent on CONFIG_SCHED_DRAWER which an
architecture may define and select.

These additional attributes will be available:

/sys/devices/system/cpu/cpuX/topology/drawer_id
/sys/devices/system/cpu/cpuX/topology/drawer_siblings
/sys/devices/system/cpu/cpuX/topology/drawer_siblings_list

Signed-off-by: Heiko Carstens 
Acked-by: Peter Zijlstra (Intel) 
Signed-off-by: Martin Schwidefsky

sched/topology: Rename topology_thread_cpumask() to topology_sibling_cpumask()

2015-05-27T13:22:15+00:00

Rename topology_thread_cpumask() to topology_sibling_cpumask()
for more consistency with scheduler code.

Signed-off-by: Bartosz Golaszewski 
Reviewed-by: Thomas Gleixner 
Acked-by: Russell King 
Acked-by: Catalin Marinas 
Cc: Benoit Cousson 
Cc: Fenghua Yu 
Cc: Guenter Roeck 
Cc: Jean Delvare 
Cc: Jonathan Corbet 
Cc: Linus Torvalds 
Cc: Oleg Drokin 
Cc: Peter Zijlstra 
Cc: Rafael J. Wysocki 
Cc: Russell King 
Cc: Viresh Kumar 
Link: http://lkml.kernel.org/r/1432645896-12588-2-git-send-email-bgolaszewski@baylibre.com
Signed-off-by: Ingo Molnar

topology: replace custom attribute macros with standard DEVICE_ATTR*

2014-11-07T19:45:00+00:00

Currently couple of custom macros are defined to declare the
device attributes. However there are already standard macros
defined in device.h that suffice the need and these custom
macros can be removed.

This patch replaces custom attribute macros with standard
DEVICE_ATTR_RO attribute

Signed-off-by: Sudeep Holla 
Cc: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

cpumask: factor out show_cpumap into separate helper function

2014-11-07T19:45:00+00:00

Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap
to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null
terminated buffer with newline.

This patch creates a new helper function cpumap_print_to_pagebuf in
cpumask.h using newly added bitmap_print_to_pagebuf and consolidates
most of those sysfs functions using the new helper function.

Signed-off-by: Sudeep Holla 
Suggested-by: Stephen Boyd 
Tested-by: Stephen Boyd 
Acked-by: "Rafael J. Wysocki" 
Acked-by: Bjorn Helgaas 
Acked-by: Peter Zijlstra (Intel) 
Cc: Greg Kroah-Hartman 
Cc: x86@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

topology: Fix compilation warning when not in SMP

2014-04-16T21:13:26+00:00

The topology_##name() macro does not use its argument when CONFIG_SMP is not
set, as it ultimately calls the cpu_data() macro.

So we avoid maintaining a possibly unused `cpu' variable, to avoid the
following compilation warning:

  drivers/base/topology.c: In function ‘show_physical_package_id’:
  drivers/base/topology.c:103:118: warning: unused variable ‘cpu’ [-Wunused-variable]
   define_id_show_func(physical_package_id);

  drivers/base/topology.c: In function ‘show_core_id’:
  drivers/base/topology.c:106:106: warning: unused variable ‘cpu’ [-Wunused-variable]
   define_id_show_func(core_id);

This can be seen with e.g. x86 defconfig and CONFIG_SMP not set.

Signed-off-by: Vincent Stehlé 
Cc: Greg Kroah-Hartman 
Cc:  # 3.10.x
Cc:  # 3.13.x
Cc:  # 3.14.x
Signed-off-by: Greg Kroah-Hartman

Merge tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2014-04-07T21:55:46+00:00

Pull CPU hotplug notifiers registration fixes from Rafael Wysocki:
 "The purpose of this single series of commits from Srivatsa S Bhat
  (with a small piece from Gautham R Shenoy) touching multiple
  subsystems that use CPU hotplug notifiers is to provide a way to
  register them that will not lead to deadlocks with CPU online/offline
  operations as described in the changelog of commit 93ae4f978ca7f ("CPU
  hotplug: Provide lockless versions of callback registration
  functions").

  The first three commits in the series introduce the API and document
  it and the rest simply goes through the users of CPU hotplug notifiers
  and converts them to using the new method"

* tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits)
  net/iucv/iucv.c: Fix CPU hotplug callback registration
  net/core/flow.c: Fix CPU hotplug callback registration
  mm, zswap: Fix CPU hotplug callback registration
  mm, vmstat: Fix CPU hotplug callback registration
  profile: Fix CPU hotplug callback registration
  trace, ring-buffer: Fix CPU hotplug callback registration
  xen, balloon: Fix CPU hotplug callback registration
  hwmon, via-cputemp: Fix CPU hotplug callback registration
  hwmon, coretemp: Fix CPU hotplug callback registration
  thermal, x86-pkg-temp: Fix CPU hotplug callback registration
  octeon, watchdog: Fix CPU hotplug callback registration
  oprofile, nmi-timer: Fix CPU hotplug callback registration
  intel-idle: Fix CPU hotplug callback registration
  clocksource, dummy-timer: Fix CPU hotplug callback registration
  drivers/base/topology.c: Fix CPU hotplug callback registration
  acpi-cpufreq: Fix CPU hotplug callback registration
  zsmalloc: Fix CPU hotplug callback registration
  scsi, fcoe: Fix CPU hotplug callback registration
  scsi, bnx2fc: Fix CPU hotplug callback registration
  scsi, bnx2i: Fix CPU hotplug callback registration
  ...

drivers/base/topology.c: Fix CPU hotplug callback registration

2014-03-20T12:43:45+00:00

Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the topology code by using this latter form of callback registration.

Cc: Ingo Molnar 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Srivatsa S. Bhat 
Signed-off-by: Rafael J. Wysocki

drivers/base: delete non-required instances of include

2014-02-14T22:31:37+00:00

None of these files are actually using any __init type directives
and hence don't need to include .  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: Len Brown 
Signed-off-by: Paul Gortmaker 
Acked-by: Pavel Machek 
Acked-by: Rafael J. Wysocki 
Acked-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

cpu topology: remove stale arch_provides_topology_pointers and define_siblings_show_map/list()

2013-07-29T20:12:45+00:00

arch_provides_topology_pointers was introduced in commit 23ca4bba3 (x86:
cleanup early per cpu variables/accesses v4) to indicate pointers to the
topology cpumask_t maps are valid to avoid copying data on to/off of the
stack.

But later in commit fbd59a8d (cpumask: Use topology_core_cpumask()/
topology_thread_cpumask()), the pointers to the topology struct cpumask maps
are always valid.

After that commit, the only difference is that there is a redundant
"unsigned int cpu = dev->id;" if arch_provides_topology_pointers defined, but
dev->id is type 'u32' which devolves to 'unsigned int' on all supported arches.
So this arch_provides_topology_pointers define is pointless and only cause
obfuscation now, remove it.

Tested on x86 machine, topology information in sys/devices/system/cpu/
cpuX/topology/ is the same after appling this patch set.

Signed-off-by: Hanjun Guo 
Signed-off-by: Greg Kroah-Hartman

drivers: delete __cpuinit usage from all remaining drivers files

2013-07-14T23:36:59+00:00

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the remaining one-off uses of the __cpuinit macros
from all C files in the drivers/* directory.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Greg Kroah-Hartman 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Paul Gortmaker