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 93ae4f978c (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.
/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=SW7Q
-----END PGP SIGNATURE-----
Merge tag 'cpu-hotplug-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
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 93ae4f978c ("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
...
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 amd-bus code in x86 by using this latter form of callback
registration.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are no callers of get_mp_bus_to_node(), so we no longer need
mp_bus_to_node[], get_mp_bus_to_node(), or set_mp_bus_to_node().
This removes them.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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.
Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings. In any case, they are temporary and harmless.
This removes all the arch/x86 uses of the __cpuinit macros from
all C files. x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Add the host bridge bus number aperture to the resource list.
Like the MMIO and I/O port apertures, this will be used when assigning
resources to hot-added devices or in the case of conflicts.
[bhelgaas: changelog, tidy printk]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This dynamically allocates struct pci_root_info instead of using a
static array.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This factors out the AMD native MMCONFIG discovery so we can use it
outside amd_bus.c.
amd_bus.c reads AMD MSRs so it can remove the MMCONFIG area from the
PCI resources. We may also need the MMCONFIG information to work
around BIOS defects in the ACPI MCFG table.
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org # 2.6.34+
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Commit 24d9b70b8c (x86: Use PCI method
for enabling AMD extended config space before MSR method) added a
message when IO access to PCI ECS was enabled via access to the NB_CFG
PCI register. This can lead to a bogus message like
[ 0.365177] Extended Config Space enabled on 0 nodes
which is misleading because IO ECS access is subsequently enabled for
AMD CPUs (that support this) by modifying the corresponding NB_CFG
MSR.
Furthermore it's not "Extended Config Space" that is enabled by this
register setting. It's the IO access that is enabled for extended
configruation space.
IMHO the ambiguous message needs to be cancelled.
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
amd_nb_misc_ids[] can live in .rodata, and enable_pci_io_ecs()
can be moved into .cpuinit.text.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Andreas Herrmann <Andreas.Herrmann3@amd.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <4D525DDD0200007800030F07@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While both methods should work equivalently well for the native
case, the Xen Dom0 case can't reliably work with the MSR one,
since there's no guarantee that the virtual CPUs it has
available fully cover all necessary physical ones.
As per the suggestion of Robert Richter the patch only adds the
PCI method, but leaves the MSR one as a fallback to cover new
systems the PCI IDs of which may not have got added to the code
base yet.
The only change in v2 is the breaking out of the new CPI
initialization method into a separate function, as requested by
Ingo.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Robert Richter <robert.richter@amd.com>
Cc: Andreas Herrmann3 <Andreas.Herrmann3@amd.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
LKML-Reference: <4D2B3FD7020000780002B67D@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
So make interface more consistent with early_res.
Later we can share some code with early_res.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-10-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Should be good for 32bit too.
-v3: cast res->start
-v4: according to Linus, to use %pR instead of cast
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-9-git-send-email-yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Prepare for 32bit pci root bus
-v2: hpa said we should compare with (resource_size_t)~0
-v3: according to Linus to use MAX_RESOURCE instead.
also need need to put related patches together
-v4: according to Andrew, use min in cap_resource()
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-8-git-send-email-yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Prepare to enable it for 32bit.
-v2: remove not needed cast
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-7-git-send-email-yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Found MSI amd k8 based laptops is hiding [0x70000000, 0x80000000) RAM
from e820.
enable amd one chain even for all.
-v2: use bool for found, according to Andrew
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-6-git-send-email-yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
We have almost the same code for mtrr cleanup and amd_bus checkup, and
this code will also be used in replacing bootmem with early_res,
so try to move them together and reuse it from different parts.
Also rename update_range to subtract_range as that is what the
function is actually doing.
-v2: update comments as Christoph requested
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-4-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Those functions are used by intel_bus.c so seperate them to another file. and
make amd_bus a bit smaller.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
For intel systems with multi IOH, we should read peer root resources
directly from PCI config space, and don't trust _CRS.
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The current mp_bus_to_node array is initialized only by AMD specific
code, since AMD platforms have registers that can be used for
determining mode numbers. On new Intel platforms it's necessary to
initialize this array as well though, otherwise all PCI node numbers
will be 0, when in fact they should be -1 (indicating that I/O isn't
tied to any particular node).
So move the mp_bus_to_node code into the common PCI code, and
initialize it early with a default value of -1. This may be overridden
later by arch code (e.g. the AMD code).
With this change, PCI consistent memory and other node specific
allocations (e.g. skbuff allocs) should occur on the "current" node.
If, for performance reasons, applications want to be bound to specific
nodes, they should open their devices only after being pinned to the
CPU where they'll run, for maximum locality.
Acked-by: Yinghai Lu <yinghai@kernel.org>
Tested-by: Jesse Brandeburg <jesse.brandeburg@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This allows us to remove adjust_transparent_bridge_resources and give
x86_pci_root_bus_res_quirks a chance when _CRS is not used or not there.
Acked-by: Gary Hade <garyhade@us.ibm.com>
Tested-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This reverts commit 9e9f46c44e.
Quoting from the commit message:
"At this point, it seems to solve more problems than it causes, so let's
try using it by default. It's an easy revert if it ends up causing
trouble."
And guess what? The _CRS code causes trouble.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
At this point, it seems to solve more problems than it causes, so let's try using it by default. It's an easy revert if it ends up causing trouble.
Reviewed-by: Yinghai Lu <yhlu.kernel@gmail.com>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
It will be overwriten later if _CRS is used, so don't bother to set it.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Rename set_pci_bus_resources_arch_default to x86_pci_root_bus_res_quirks, move
the weak version from common.c to i386.c, and before calling, make sure it's a
root bus.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: cleanup
Now that arch/x86/pci/pci.h is used in a number of other places as well,
move the lowlevel x86 pci definitions into the architecture include files.
(not to be confused with the existing arch/x86/include/asm/pci.h file,
which provides public details about x86 PCI)
Tested on: X86_32_UP, X86_32_SMP and X86_64_SMP
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Jan Beulich wrote:
> Even worse - this would even try to access the MSR on non-AMD CPUs
> (currently probably prevented just by the fact that only AMD ones use
> family values of 0x10 or higher).
This patch adds cpu vendor check to the postcore_initcalls.
Reported-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix merge fallout:
arch/x86/pci/amd_bus.c: In function ‘enable_pci_io_ecs':
arch/x86/pci/amd_bus.c:581: error: too many arguments to function ‘on_each_cpu'
Signed-off-by: Ingo Molnar <mingo@elte.hu>
"Form follows function". Code is now where it belongs to.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The name fits better since this is code not only for K8.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
