Move the defintion and lock helper routines for the cpu hotplug driver
lock from pseries to powerpc code to avoid build breaks for platforms
other than pseries that use cpu hotplug.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
And add the __acquires() and __releases() annotations, while at it.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The recent patch to add cpu offline/online as part of the DLPAR
process for pseries causes a build break if CONFIG_SMP is not
defined. Original patch here;
http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-November/078299.html
This corrects the build break by moving the online_node_cpus
and offline_node_cpus under the #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
portions of dlpar.c.
This patch also slightly modifies the online_node_cpus and offline_node_cpus
routines to prepend dlpar_ to the them and make them static. These two
routine are only used in the dlpar add/remove of cpus and these changes
should help clarify that.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the cpu-allocation/deallocation process comprises of two steps:
- Set the indicators and to update the device tree with DLPAR node
information.
- Online/offline the allocated/deallocated CPU.
This is achieved by writing to the sysfs tunables "probe" during allocation
and "release" during deallocation.
At the sametime, the userspace can independently online/offline the CPUs of
the system using the sysfs tunable "online".
It is quite possible that when a userspace tool offlines a CPU
for the purpose of deallocation and is in the process of updating the device
tree, some other userspace tool could bring the CPU back online by writing to
the "online" sysfs tunable thereby causing the deallocate process to fail.
The solution to this is to serialize writes to the "probe/release" sysfs
tunable with the writes to the "online" sysfs tunable.
This patch employs a mutex to provide this serialization, which is a no-op on
all architectures except PPC_PSERIES
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the cpu-allocation/deallocation on pSeries is a
two step process from the Userspace.
- Set the indicators and update the device tree by writing to the sysfs
tunable "probe" during allocation and "release" during deallocation.
- Online / Offline the CPUs of the allocated/would_be_deallocated node by
writing to the sysfs tunable "online".
This patch adds kernel code to online/offline the CPUs soon_after/just_before
they have been allocated/would_be_deallocated. This way, the userspace tool
that performs DLPAR operations would only have to deal with one set of sysfs
tunables namely "probe" and release".
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds the specific routines to probe and release (add and remove)
cpu resource for the powerpc pseries platform and registers these handlers
with the ppc_md callout structure.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Dynamic Logical Partitioning capabilities of the powerpc pseries platform
allows for the addition and removal of resources (i.e. CPU's, memory, and PCI
devices) from a partition. The removal of a resource involves
removing the resource's node from the device tree and then returning the
resource to firmware via the rtas set-indicator call. To add a resource, it
is first obtained from firmware via the rtas set-indicator call and then a
new device tree node is created using the ibm,configure-coinnector rtas call
and added to the device tree.
This patch provides the kernel DLPAR infrastructure in a new filed named
dlpar.c. The functionality provided is for acquiring and releasing a resource
from firmware and the parsing of information returned from the
ibm,configure-connector rtas call. Additionally this exports the pSeries
reconfiguration notifier chain so that it can be invoked when device tree
updates are made.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Nathan Fontenot