Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds support to real-mode KVM to search for a core
running in the host partition and send it an IPI message with
VCPU to be woken. This avoids having to switch to the host
partition to complete an H_IPI hypercall when the VCPU which
is the target of the the H_IPI is not loaded (is not running
in the guest).
The patch also includes the support in the IPI handler running
in the host to do the wakeup by calling kvmppc_xics_ipi_action
for the PPC_MSG_RM_HOST_ACTION message.
When a guest is being destroyed, we need to ensure that there
are no pending IPIs waiting to wake up a VCPU before we free
the VCPUs of the guest. This is accomplished by:
- Forces a PPC_MSG_CALL_FUNCTION IPI to be completed by all CPUs
before freeing any VCPUs in kvm_arch_destroy_vm().
- Any PPC_MSG_RM_HOST_ACTION messages must be executed first
before any other PPC_MSG_CALL_FUNCTION messages.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
smp_muxed_ipi_message_pass() invokes smp_ops->cause_ipi, which
uses an ioremapped address to access registers on the XICS
interrupt controller to cause the IPI. Because of this real
mode callers cannot call smp_muxed_ipi_message_pass() for IPI
messaging.
This patch creates a separate function smp_muxed_ipi_set_message
just to set the IPI message without the cause_ipi routine.
After calling this function to set the IPI message, real
mode callers must cause the IPI by writing to the XICS registers
directly.
As part of this, we also change smp_muxed_ipi_message_pass
to call smp_muxed_ipi_set_message to set the message instead
of doing it directly inside the routine.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch increases the number of demuxed messages for a
controller with a single ipi to 8 for 64-bit systems.
This is required because we want to use the IPI mechanism
to send messages from a CPU running in KVM real mode in a
guest to a CPU in the host to take some action. Currently,
we only support 4 messages and all 4 are already taken.
Define a fifth message PPC_MSG_RM_HOST_ACTION for this
purpose.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Anton has a busy ppc64le KVM box where guests sometimes hit the infamous
"kernel BUG at kernel/smpboot.c:134!" issue during boot:
BUG_ON(td->cpu != smp_processor_id());
Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops
output confirms it:
CPU: 0
Comm: watchdog/130
The problem is that we aren't ensuring the CPU active bit is set for the
secondary before allowing the master to continue on. The master unparks
the secondary CPU's kthreads and the scheduler looks for a CPU to run
on. It calls select_task_rq() and realises the suggested CPU is not in
the cpus_allowed mask. It then ends up in select_fallback_rq(), and
since the active bit isnt't set we choose some other CPU to run on.
This seems to have been introduced by 6acbfb9697 "sched: Fix hotplug
vs. set_cpus_allowed_ptr()", which changed from setting active before
online to setting active after online. However that was in turn fixing a
bug where other code assumed an active CPU was also online, so we can't
just revert that fix.
The simplest fix is just to spin waiting for both active & online to be
set. We already have a barrier prior to set_cpu_online() (which also
sets active), to ensure all other setup is completed before online &
active are set.
Fixes: 6acbfb9697 ("sched: Fix hotplug vs. set_cpus_allowed_ptr()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Including:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath device
tree content, e300 machine check support, t1040 corenet error reporting,
and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath
device tree content, e300 machine check support, t1040 corenet
error reporting, and various cleanups and fixes"
* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
cxl: Add missing return statement after handling AFU errror
cxl: Fail AFU initialisation if an invalid configuration record is found
cxl: Export optional AFU configuration record in sysfs
powerpc/mm: Warn on flushing tlb page in kernel context
powerpc/powernv: Add OPAL soft-poweroff routine
powerpc/perf/hv-24x7: Document sysfs event description entries
powerpc/perf/hv-gpci: add the remaining gpci requests
powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
perf: add PMU_EVENT_ATTR_STRING() helper
perf: provide sysfs_show for struct perf_pmu_events_attr
powerpc/kernel: Avoid initializing device-tree pointer twice
powerpc: Remove old compile time disabled syscall tracing code
powerpc/kernel: Make syscall_exit a local label
cxl: Fix device_node reference counting
powerpc/mm: bail out early when flushing TLB page
powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
perf/powerpc: reset event hw state when adding it to the PMU
powerpc/qe: Use strlcpy()
...
Remove slice_set_psize() which is not used.
It was added in 3a8247cc2c "powerpc: Only demote individual slices
rather than whole process" but was never used.
Remove vsx_assist_exception() which is not used.
It was added in ce48b21007 "powerpc: Add VSX context save/restore,
ptrace and signal support" but was never used.
Remove generic_mach_cpu_die() which is not used.
Its last caller was removed in 375f561a41 "powerpc/powernv: Always go
into nap mode when CPU is offline".
Remove mpc7448_hpc2_power_off() and mpc7448_hpc2_halt() which are
unused.
These were introduced in c5d56332fd "[POWERPC] Add general support for
mpc7448hpc2 (Taiga) platform" but were never used.
This was partially found by using a static code analysis program called
cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
[mpe: Update changelog with details on when/why they are unused]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This reverts commit 7c5c92ed56.
Although this did fix the bug it was aimed at, it also broke secondary
startup on platforms that use give/take_timebase(). Unfortunately we
didn't detect that while it was in next.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
I have a busy ppc64le KVM box where guests sometimes hit the infamous
"kernel BUG at kernel/smpboot.c:134!" issue during boot:
BUG_ON(td->cpu != smp_processor_id());
Basically a per CPU hotplug thread scheduled on the wrong CPU. The oops
output confirms it:
CPU: 0
Comm: watchdog/130
The problem is that we aren't ensuring the CPU active and online bits are set
before allowing the master to continue on. The master unparks the secondary
CPUs kthreads and the scheduler looks for a CPU to run on. It calls
select_task_rq and realises the suggested CPU is not in the cpus_allowed
mask. It then ends up in select_fallback_rq, and since the active and
online bits aren't set we choose some other CPU to run on.
Cc: stable@vger.kernel.org
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This still has not been merged and now powerpc is the only arch that does
not have this change. Sorry about missing linuxppc-dev before.
V2->V2
- Fix up to work against 3.18-rc1
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
__this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
__this_cpu_inc(y)
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
[mpe: Fix build errors caused by set/or_softirq_pending(), and rework
assignment in __set_breakpoint() to use memcpy().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As Nish suggested, it makes more sense to init the numa node informatiion
for present cpus at boottime, which could also avoid WARN_ON(1) in
numa_setup_cpu().
With this change, we also need to change the smp_prepare_cpus() to set up
numa information only on present cpus.
For those possible, but not present cpus, their numa information
will be set up after they are started, as the original code did before commit
2fabf084b6.
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Fix a number of places where global functions were not including
their prototype. This ensures the prototype and the function match.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There is an issue currently where NUMA information is used on powerpc
(and possibly ia64) before it has been read from the device-tree, which
leads to large slab consumption with CONFIG_SLUB and memoryless nodes.
NUMA powerpc non-boot CPU's cpu_to_node/cpu_to_mem is only accurate
after start_secondary(), similar to ia64, which is invoked via
smp_init().
Commit 6ee0578b4d ("workqueue: mark init_workqueues() as
early_initcall()") made init_workqueues() be invoked via
do_pre_smp_initcalls(), which is obviously before the secondary
processors are online.
Additionally, the following commits changed init_workqueues() to use
cpu_to_node to determine the node to use for kthread_create_on_node:
bce903809a ("workqueue: add wq_numa_tbl_len and
wq_numa_possible_cpumask[]")
f3f90ad469 ("workqueue: determine NUMA node of workers accourding to
the allowed cpumask")
Therefore, when init_workqueues() runs, it sees all CPUs as being on
Node 0. On LPARs or KVM guests where Node 0 is memoryless, this leads to
a high number of slab deactivations
(http://www.spinics.net/lists/linux-mm/msg67489.html).
Fix this by initializing the powerpc-specific CPU<->node/local memory
node mapping as early as possible, which on powerpc is
do_init_bootmem(). Currently that function initializes the mapping for
the boot CPU, but we extend it to setup the mapping for all possible
CPUs. Then, in smp_prepare_cpus(), we can correspondingly set the
per-cpu values for all possible CPUs. That ensures that before the
early_initcalls run (and really as early as possible), the per-cpu NUMA
mapping is accurate.
While testing memoryless nodes on PowerKVM guests with a fix to the
workqueue logic to use cpu_to_mem() instead of cpu_to_node(), with a
guest topology of:
available: 2 nodes (0-1)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
node 1 size: 16336 MB
node 1 free: 15329 MB
node distances:
node 0 1
0: 10 40
1: 40 10
the slab consumption decreases from
Slab: 932416 kB
SUnreclaim: 902336 kB
to
Slab: 395264 kB
SUnreclaim: 359424 kB
And we a corresponding increase in the slab efficiency from
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 337 MB 11.28% 100.00%
task_struct 288 MB 9.93% 100.00%
to
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 37 MB 100.00% 100.00%
task_struct 31 MB 100.00% 100.00%
Powerpc didn't support memoryless nodes until recently (64bb80d87f
"powerpc/numa: Enable CONFIG_HAVE_MEMORYLESS_NODES" and 8c27226119
"powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"). Those commits also
helped improve memory consumption with these kind of environments.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 143e1e28cb (sched: Rework sched_domain topology definition)
introduced a number of functions with a return value of 'const int'.
gcc doesn't know what to do with that and, if the kernel is compiled
with W=1, complains with the following warnings whenever sched.h
is included.
include/linux/sched.h:875:25: warning: type qualifiers ignored on function return type
include/linux/sched.h:882:25: warning: type qualifiers ignored on function return type
include/linux/sched.h:889:25: warning: type qualifiers ignored on function return type
include/linux/sched.h:1002:21: warning: type qualifiers ignored on function return type
Commits fb2aa855 (sched, ARM: Create a dedicated scheduler topology table)
and 607b45e9a (sched, powerpc: Create a dedicated topology table) introduce
the same warning in the arm and powerpc code.
Drop 'const' from the function declarations to fix the problem.
The fix for all three patches has to be applied together to avoid
compilation failures for the affected architectures.
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1403658329-13196-1-git-send-email-linux@roeck-us.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull more scheduler updates from Ingo Molnar:
"Second round of scheduler changes:
- try-to-wakeup and IPI reduction speedups, from Andy Lutomirski
- continued power scheduling cleanups and refactorings, from Nicolas
Pitre
- misc fixes and enhancements"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Delete extraneous extern for to_ratio()
sched/idle: Optimize try-to-wake-up IPI
sched/idle: Simplify wake_up_idle_cpu()
sched/idle: Clear polling before descheduling the idle thread
sched, trace: Add a tracepoint for IPI-less remote wakeups
cpuidle: Set polling in poll_idle
sched: Remove redundant assignment to "rt_rq" in update_curr_rt(...)
sched: Rename capacity related flags
sched: Final power vs. capacity cleanups
sched: Remove remaining dubious usage of "power"
sched: Let 'struct sched_group_power' care about CPU capacity
sched/fair: Disambiguate existing/remaining "capacity" usage
sched/fair: Change "has_capacity" to "has_free_capacity"
sched/fair: Remove "power" from 'struct numa_stats'
sched: Fix signedness bug in yield_to()
sched/fair: Use time_after() in record_wakee()
sched/balancing: Reduce the rate of needless idle load balancing
sched/fair: Fix unlocked reads of some cfs_b->quota/period
Pull powerpc updates from Ben Herrenschmidt:
"Here is the bulk of the powerpc changes for this merge window. It got
a bit delayed in part because I wasn't paying attention, and in part
because I discovered I had a core PCI change without a PCI maintainer
ack in it. Bjorn eventually agreed it was ok to merge it though we'll
probably improve it later and I didn't want to rebase to add his ack.
There is going to be a bit more next week, essentially fixes that I
still want to sort through and test.
The biggest item this time is the support to build the ppc64 LE kernel
with our new v2 ABI. We previously supported v2 userspace but the
kernel itself was a tougher nut to crack. This is now sorted mostly
thanks to Anton and Rusty.
We also have a fairly big series from Cedric that add support for
64-bit LE zImage boot wrapper. This was made harder by the fact that
traditionally our zImage wrapper was always 32-bit, but our new LE
toolchains don't really support 32-bit anymore (it's somewhat there
but not really "supported") so we didn't want to rely on it. This
meant more churn that just endian fixes.
This brings some more LE bits as well, such as the ability to run in
LE mode without a hypervisor (ie. under OPAL firmware) by doing the
right OPAL call to reinitialize the CPU to take HV interrupts in the
right mode and the usual pile of endian fixes.
There's another series from Gavin adding EEH improvements (one day we
*will* have a release with less than 20 EEH patches, I promise!).
Another highlight is the support for the "Split core" functionality on
P8 by Michael. This allows a P8 core to be split into "sub cores" of
4 threads which allows the subcores to run different guests under KVM
(the HW still doesn't support a partition per thread).
And then the usual misc bits and fixes ..."
[ Further delayed by gmail deciding that BenH is a dirty spammer.
Google knows. ]
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (155 commits)
powerpc/powernv: Add missing include to LPC code
selftests/powerpc: Test the THP bug we fixed in the previous commit
powerpc/mm: Check paca psize is up to date for huge mappings
powerpc/powernv: Pass buffer size to OPAL validate flash call
powerpc/pseries: hcall functions are exported to modules, need _GLOBAL_TOC()
powerpc: Exported functions __clear_user and copy_page use r2 so need _GLOBAL_TOC()
powerpc/powernv: Set memory_block_size_bytes to 256MB
powerpc: Allow ppc_md platform hook to override memory_block_size_bytes
powerpc/powernv: Fix endian issues in memory error handling code
powerpc/eeh: Skip eeh sysfs when eeh is disabled
powerpc: 64bit sendfile is capped at 2GB
powerpc/powernv: Provide debugfs access to the LPC bus via OPAL
powerpc/serial: Use saner flags when creating legacy ports
powerpc: Add cpu family documentation
powerpc/xmon: Fix up xmon format strings
powerpc/powernv: Add calls to support little endian host
powerpc: Document sysfs DSCR interface
powerpc: Fix regression of per-CPU DSCR setting
powerpc: Split __SYSFS_SPRSETUP macro
arch: powerpc/fadump: Cleaning up inconsistent NULL checks
...
It is better not to think about compute capacity as being equivalent
to "CPU power". The upcoming "power aware" scheduler work may create
confusion with the notion of energy consumption if "power" is used too
liberally.
Let's rename the following feature flags since they do relate to capacity:
SD_SHARE_CPUPOWER -> SD_SHARE_CPUCAPACITY
ARCH_POWER -> ARCH_CAPACITY
NONTASK_POWER -> NONTASK_CAPACITY
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linaro-kernel@lists.linaro.org
Cc: Andy Fleming <afleming@freescale.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/n/tip-e93lpnxb87owfievqatey6b5@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To support split core we need to change the check in __cpu_up() that
determines if a cpu is allowed to come online.
Currently we refuse to online cpus which are not the primary thread
within their core.
On POWER8 with split core support this check needs to instead refuse to
online cpus which are not the primary thread within their *sub* core.
On POWER7 and other systems that do not support split core,
threads_per_subcore == threads_per_core and so the check is equivalent.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As part of the support for split core on POWER8, we want to be able to
block splitting of the core while KVM VMs are active.
The logic to do that would be exactly the same as the code we currently
have for inhibiting onlining of secondaries.
Instead of adding an identical mechanism to block split core, rework the
secondary inhibit code to be a "HV KVM is active" check. We can then use
that in both the cpu hotplug code and the upcoming split core code.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Alexander Graf <agraf@suse.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Based off 3bccd996 for ia64, convert powerpc to use the generic per-CPU
topology tracking, specifically:
initialize per cpu numa_node entry in start_secondary
remove the powerpc cpu_to_node()
define CONFIG_USE_PERCPU_NUMA_NODE_ID if NUMA
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
For scalability and performance reasons, we want the tick broadcast IPIs
to be handled as efficiently as possible. Fixed IPI messages
are one of the most efficient mechanisms available - they are faster than
the smp_call_function mechanism because the IPI handlers are fixed and hence
they don't involve costly operations such as adding IPI handlers to the target
CPU's function queue, acquiring locks for synchronization etc.
Luckily we have an unused IPI message slot, so use that to implement
tick broadcast IPIs efficiently.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
[Functions renamed to tick_broadcast* and Changelog modified by
Preeti U. Murthy<preeti@linux.vnet.ibm.com>]
Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Geoff Levand <geoff@infradead.org> [For the PS3 part]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The IPI handlers for both PPC_MSG_CALL_FUNC and PPC_MSG_CALL_FUNC_SINGLE map
to a common implementation - generic_smp_call_function_single_interrupt(). So,
we can consolidate them and save one of the IPI message slots, (which are
precious on powerpc, since only 4 of those slots are available).
So, implement the functionality of PPC_MSG_CALL_FUNC_SINGLE using
PPC_MSG_CALL_FUNC itself and release its IPI message slot, so that it can be
used for something else in the future, if desired.
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Acked-by: Geoff Levand <geoff@infradead.org> [For the PS3 part]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Merge a pile of fixes that went into the "merge" branch (3.13-rc's) such
as Anton Little Endian fixes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cpu_to_core_id() is missing a byteswap:
cat /sys/devices/system/cpu/cpu63/topology/core_id
201326592
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since not need 'max_cpus' after the related commit, the related code
are useless too, need be removed.
The related commit:
c1aa687 powerpc: Clean up obsolete code relating to decrementer and timebase
The related warning:
arch/powerpc/kernel/smp.c:323:43: warning: parameter ‘max_cpus’ set but not used [-Wunused-but-set-parameter]
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Up until now we have only used cpu_to_chip_id() in the topology code,
which is only used on SMP builds. However my recent commit a4da0d5
"Implement arch_get_random_long/int() for powernv" added a usage when
SMP=n, breaking the build.
Move cpu_to_chip_id() into prom.c so it is available for SMP=n builds.
We would move the extern to prom.h, but that breaks the include in
topology.h. Instead we leave it in smp.h, but move it out of the
CONFIG_SMP #ifdef. We also need to include asm/smp.h in rng.c, because
the linux version skips asm/smp.h on UP. What a mess.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cpu_hotplug_driver_lock() serializes CPU online/offline operations
when ARCH_CPU_PROBE_RELEASE is set. This lock interface is no longer
necessary with the following reason:
- lock_device_hotplug() now protects CPU online/offline operations,
including the probe & release interfaces enabled by
ARCH_CPU_PROBE_RELEASE. The use of cpu_hotplug_driver_lock() is
redundant.
- cpu_hotplug_driver_lock() is only valid when ARCH_CPU_PROBE_RELEASE
is defined, which is misleading and is only enabled on powerpc.
This patch removes the cpu_hotplug_driver_lock() interface. As
a result, ARCH_CPU_PROBE_RELEASE only enables / disables the cpu
probe & release interface as intended. There is no functional change
in this patch.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
powerpc allmodconfig build fails with:
ERROR: ".cpu_to_chip_id" [drivers/block/mtip32xx/mtip32xx.ko] undefined!
The problem was introduced with commit 15863ff3b (powerpc: Make chip-id
information available to userspace).
Export the missing symbol.
Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Cc: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add little endian support for demuxing SMP IPIs
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
So far "/sys/devices/system/cpu/cpuX/topology/physical_package_id"
was always default (-1) on ppc64 architecture.
Now, some systems have an ibm,chip-id property in the cpu nodes in
the device tree. On these systems, we now use this information to
display physical_package_id.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some systems have an ibm,chip-id property in the cpu nodes in the
device tree. On these systems, we now use that to compute the
cpu_core_mask (i.e. the set of core siblings) rather than looking
at cache properties.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Tested-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This factors out the details of updating cpu_core_mask into a separate
function, to make it easier to change how the mask is calculated later.
This makes no functional change.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cell and PSeries both implemented their own versions of a
cpu_bootable smp_op which do the same thing (well, the PSeries
one has support for more than 2 threads). Copy the PSeries one
to generic code, and rename it smp_generic_cpu_bootable.
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Address some of the trivial sparse warnings in arch/powerpc.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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 powerpc uses of the __cpuinit macros. There
are no __CPUINIT users in assembly files in powerpc.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/20130321215235.026838003@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It seems, we're fine with just annotating the two functions.
Thus, this fixes the following build warnings on ppc64:
WARNING: arch/powerpc/sysdev/xics/built-in.o(.text+0x1664):
The function .ics_rtas_init() references
the function __init .xics_register_ics().
This is often because .ics_rtas_init lacks a __init
annotation or the annotation of .xics_register_ics is wrong.
WARNING: arch/powerpc/sysdev/built-in.o(.text+0x6044):
The function .ics_rtas_init() references
the function __init .xics_register_ics().
This is often because .ics_rtas_init lacks a __init
annotation or the annotation of .xics_register_ics is wrong.
WARNING: arch/powerpc/kernel/built-in.o(.text+0x2db30):
The function .start_secondary() references
the function __cpuinit .vdso_getcpu_init().
This is often because .start_secondary lacks a __cpuinit
annotation or the annotation of .vdso_getcpu_init is wrong.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.
This change removes the use of __devinit, __devexit_p, __devinitdata,
__devinitconst, and __devexit from these drivers.
Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a Book3S HV KVM guest is running, we need the host to be in
single-thread mode, that is, all of the cores (or at least all of
the cores where the KVM guest could run) to be running only one
active hardware thread. This is because of the hardware restriction
in POWER processors that all of the hardware threads in the core
must be in the same logical partition. Complying with this restriction
is much easier if, from the host kernel's point of view, only one
hardware thread is active.
This adds two hooks in the SMP hotplug code to allow the KVM code to
make sure that secondary threads (i.e. hardware threads other than
thread 0) cannot come online while any KVM guest exists. The KVM
code still has to check that any core where it runs a guest has the
secondary threads offline, but having done that check it can now be
sure that they will not come online while the guest is running.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
During suspend, all interrupts including IPI will be disabled. In this case,
the suspend process will hang in SMP. To prevent this, pass the flag
IRQF_NO_SUSPEND when requesting IPI irq.
Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
In the case of cpu hotplug, the cpu_state should be set to CPU_UP_PREPARE
when kicking cpu. Otherwise, the cpu_state is always CPU_DEAD after
calling generic_set_cpu_dead(), which makes the delay in generic_cpu_die()
not happen.
Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
We have been observing hangs, both of KVM guest vcpu tasks and more
generally, where a process that is woken doesn't properly wake up and
continue to run, but instead sticks in TASK_WAKING state. This
happens because the update of rq->wake_list in ttwu_queue_remote()
is not ordered with the update of ipi_message in
smp_muxed_ipi_message_pass(), and the reading of rq->wake_list in
scheduler_ipi() is not ordered with the reading of ipi_message in
smp_ipi_demux(). Thus it is possible for the IPI receiver not to see
the updated rq->wake_list and therefore conclude that there is nothing
for it to do.
In order to make sure that anything done before smp_send_reschedule()
is ordered before anything done in the resulting call to scheduler_ipi(),
this adds barriers in smp_muxed_message_pass() and smp_ipi_demux().
The barrier in smp_muxed_message_pass() is a full barrier to ensure that
there is a full ordering between the smp_send_reschedule() caller and
scheduler_ipi(). In smp_ipi_demux(), we use xchg() rather than
xchg_local() because xchg() includes release and acquire barriers.
Using xchg() rather than xchg_local() makes sense given that
ipi_message is not just accessed locally.
This moves the barrier between setting the message and calling the
cause_ipi() function into the individual cause_ipi implementations.
Most of them -- those that used outb, out_8 or similar -- already had
a full barrier because out_8 etc. include a sync before the MMIO
store. This adds an explicit barrier in the two remaining cases.
These changes made no measurable difference to the speed of IPIs as
measured using a simple ping-pong latency test across two CPUs on
different cores of a POWER7 machine.
The analysis of the reason why processes were not waking up properly
is due to Milton Miller.
Cc: stable@vger.kernel.org # v3.0+
Reported-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have a request for a fast method of getting CPU and NUMA node IDs
from userspace. This patch implements a getcpu VDSO function,
similar to x86.
Ben suggested we use SPRG3 which is userspace readable. SPRG3 can be
modified by a KVM guest, so we save the SPRG3 value in the paca and
restore it when transitioning from the guest to the host.
I have a glibc patch that implements sched_getcpu on top of this.
Testing on a POWER7:
baseline: 538 cycles
vdso: 30 cycles
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
1) call_function.lock used in smp_call_function_many() is just to protect
call_function.queue and &data->refs, cpu_online_mask is outside of the
lock. And it's not necessary to protect cpu_online_mask,
because data->cpumask is pre-calculate and even if a cpu is brougt up
when calling arch_send_call_function_ipi_mask(), it's harmless because
validation test in generic_smp_call_function_interrupt() will take care
of it.
2) For cpu down issue, stop_machine() will guarantee that no concurrent
smp_call_fuction() is processing.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/20120420124557.311212868@linutronix.de
Preparatory patch to make the idle thread allocation for secondary
cpus generic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
Disintegrate asm/system.h for PowerPC.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cc: linuxppc-dev@lists.ozlabs.org
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
arm: fix up some samsung merge sysdev conversion problems
firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
Drivers:hv: Fix a bug in vmbus_driver_unregister()
driver core: remove __must_check from device_create_file
debugfs: add missing #ifdef HAS_IOMEM
arm: time.h: remove device.h #include
driver-core: remove sysdev.h usage.
clockevents: remove sysdev.h
arm: convert sysdev_class to a regular subsystem
arm: leds: convert sysdev_class to a regular subsystem
kobject: remove kset_find_obj_hinted()
m86k: gpio - convert sysdev_class to a regular subsystem
mips: txx9_sram - convert sysdev_class to a regular subsystem
mips: 7segled - convert sysdev_class to a regular subsystem
sh: dma - convert sysdev_class to a regular subsystem
sh: intc - convert sysdev_class to a regular subsystem
power: suspend - convert sysdev_class to a regular subsystem
power: qe_ic - convert sysdev_class to a regular subsystem
power: cmm - convert sysdev_class to a regular subsystem
s390: time - convert sysdev_class to a regular subsystem
...
Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
- arch/arm/mach-exynos/cpu.c
- arch/arm/mach-exynos/irq-eint.c
- arch/arm/mach-s3c64xx/common.c
- arch/arm/mach-s3c64xx/cpu.c
- arch/arm/mach-s5p64x0/cpu.c
- arch/arm/mach-s5pv210/common.c
- arch/arm/plat-samsung/include/plat/cpu.h
- arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.
The microcode_core.c patch was provided by Stephen Rothwell
<sfr@canb.auug.org.au> who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
IPI handlers cannot be threaded. Remove the obsolete IRQF_DISABLED
flag (see commit e58aa3d2) while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).
So now this flag is a NOOP and can be removed.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
All these files were including module.h just for the basic
EXPORT_SYMBOL infrastructure. We can shift them off to the
export.h header which is a way smaller footprint and thus
realize some compile time gains.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This adds more generic support for doing CPU hotplug with a simple
idle loop and no actual reset of the processors. The generic
smp_generic_kick_cpu() does the hotplug bringup trick if the PACA
shows that the CPU has already been started at boot and we provide
an accessor for the CPU state.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (99 commits)
drivers/virt: add missing linux/interrupt.h to fsl_hypervisor.c
powerpc/85xx: fix mpic configuration in CAMP mode
powerpc: Copy back TIF flags on return from softirq stack
powerpc/64: Make server perfmon only built on ppc64 server devices
powerpc/pseries: Fix hvc_vio.c build due to recent changes
powerpc: Exporting boot_cpuid_phys
powerpc: Add CFAR to oops output
hvc_console: Add kdb support
powerpc/pseries: Fix hvterm_raw_get_chars to accept < 16 chars, fixing xmon
powerpc/irq: Quieten irq mapping printks
powerpc: Enable lockup and hung task detectors in pseries and ppc64 defeconfigs
powerpc: Add mpt2sas driver to pseries and ppc64 defconfig
powerpc: Disable IRQs off tracer in ppc64 defconfig
powerpc: Sync pseries and ppc64 defconfigs
powerpc/pseries/hvconsole: Fix dropped console output
hvc_console: Improve tty/console put_chars handling
powerpc/kdump: Fix timeout in crash_kexec_wait_realmode
powerpc/mm: Fix output of total_ram.
powerpc/cpufreq: Add cpufreq driver for Momentum Maple boards
powerpc: Correct annotations of pmu registration functions
...
Fix up trivial Kconfig/Makefile conflicts in arch/powerpc, drivers, and
drivers/cpufreq
This adds support for KVM running on 64-bit Book 3S processors,
specifically POWER7, in hypervisor mode. Using hypervisor mode means
that the guest can use the processor's supervisor mode. That means
that the guest can execute privileged instructions and access privileged
registers itself without trapping to the host. This gives excellent
performance, but does mean that KVM cannot emulate a processor
architecture other than the one that the hardware implements.
This code assumes that the guest is running paravirtualized using the
PAPR (Power Architecture Platform Requirements) interface, which is the
interface that IBM's PowerVM hypervisor uses. That means that existing
Linux distributions that run on IBM pSeries machines will also run
under KVM without modification. In order to communicate the PAPR
hypercalls to qemu, this adds a new KVM_EXIT_PAPR_HCALL exit code
to include/linux/kvm.h.
Currently the choice between book3s_hv support and book3s_pr support
(i.e. the existing code, which runs the guest in user mode) has to be
made at kernel configuration time, so a given kernel binary can only
do one or the other.
This new book3s_hv code doesn't support MMIO emulation at present.
Since we are running paravirtualized guests, this isn't a serious
restriction.
With the guest running in supervisor mode, most exceptions go straight
to the guest. We will never get data or instruction storage or segment
interrupts, alignment interrupts, decrementer interrupts, program
interrupts, single-step interrupts, etc., coming to the hypervisor from
the guest. Therefore this introduces a new KVMTEST_NONHV macro for the
exception entry path so that we don't have to do the KVM test on entry
to those exception handlers.
We do however get hypervisor decrementer, hypervisor data storage,
hypervisor instruction storage, and hypervisor emulation assist
interrupts, so we have to handle those.
In hypervisor mode, real-mode accesses can access all of RAM, not just
a limited amount. Therefore we put all the guest state in the vcpu.arch
and use the shadow_vcpu in the PACA only for temporary scratch space.
We allocate the vcpu with kzalloc rather than vzalloc, and we don't use
anything in the kvmppc_vcpu_book3s struct, so we don't allocate it.
We don't have a shared page with the guest, but we still need a
kvm_vcpu_arch_shared struct to store the values of various registers,
so we include one in the vcpu_arch struct.
The POWER7 processor has a restriction that all threads in a core have
to be in the same partition. MMU-on kernel code counts as a partition
(partition 0), so we have to do a partition switch on every entry to and
exit from the guest. At present we require the host and guest to run
in single-thread mode because of this hardware restriction.
This code allocates a hashed page table for the guest and initializes
it with HPTEs for the guest's Virtual Real Memory Area (VRMA). We
require that the guest memory is allocated using 16MB huge pages, in
order to simplify the low-level memory management. This also means that
we can get away without tracking paging activity in the host for now,
since huge pages can't be paged or swapped.
This also adds a few new exports needed by the book3s_hv code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
This is used to round-robin TLBCAM entries.
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
On many platforms (including pSeries), smp_ops->message_pass is always
smp_muxed_ipi_message_pass. This changes arch/powerpc/kernel/smp.c so
that if smp_ops->message_pass is NULL, it calls smp_muxed_ipi_message_pass
directly.
This means that a platform doesn't need to set both .message_pass and
.cause_ipi, only one of them. It is a slight performance improvement
in that it gets rid of an indirect function call at the expense of a
predictable conditional branch.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The cell iic interrupt controller has enough software caused interrupts
to use a unique interrupt for each of the 4 messages powerpc uses.
This means each interrupt gets its own irq action/data combination.
Use the seperate, optimized, arch common ipi action functions
registered via the helper smp_request_message_ipi instead passing the
message as action data to a single action that then demultipexes to
the required acton via a switch statement.
smp_request_message_ipi will register the action as IRQF_PER_CPU
and IRQF_DISABLED, and WARN if the allocation fails for some reason,
so no need to print on that failure. It will return positive if
the message will not be used by the kernel, in which case we can
free the virq.
In addition to elimiating inefficient code, this also corrects the
error that a kernel built with kexec but without a debugger would
not register the ipi for kdump to notify the other cpus of a crash.
This also restores the debugger action to be static to kernel/smp.c.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Manual merge of arch/powerpc/kernel/smp.c and add missing scheduler_ipi()
call to arch/powerpc/platforms/cell/interrupt.c
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since there are only 4 messages, we can replace the atomic bit set
(which uses atomic load reserve and store conditional sequence) with
a byte stores to seperate bytes. We still have to perform a load
reserve and store conditional sequence to avoid loosing messages on
reception but we can do that with a single call to xchg.
The do {} while and __BIG_ENDIAN specific mask testing was chosen by
looking at the generated asm code. On gcc-4.4, the bit masking becomes
a simple bit mask and test of the register returned from xchg without
storing and loading the value to the stack like attempts with a union
of bytes and an int (or worse, loading single bit constants from the
constant pool into non-voliatle registers that had to be preseved on
the stack). The do {} while avoids an unconditional branch to the
end of the loop to test the entry / repeat condition of a while loop
and instead optimises for the expected single iteration of the loop.
We have a full mb() at the beginning to cover ordering between send,
ipi, and receive so we can use xchg_local and forgo the further
acquire and release barriers of xchg.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Compile the new smp ipi mux and demux code only if a platform
will make use of it. The new config is selected as required.
The new cause_ipi smp op is only available conditionally to point out
configs where the select is required; this makes setting the op an
immediate fail instead of a deferred unresolved symbol at link.
This also creates a new config for power surge powermac upgrade support
that can be disabled in expert mode but is default on.
I also removed the depends / default y on CONFIG_XICS since it is selected
by PSERIES.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Consolidate the mux and demux of ipi messages into smp.c and call
a new smp_ops callback to actually trigger the ipi.
The powerpc architecture code is optimised for having 4 distinct
ipi triggers, which are mapped to 4 distinct messages (ipi many, ipi
single, scheduler ipi, and enter debugger). However, several interrupt
controllers only provide a single software triggered interrupt that
can be delivered to each cpu. To resolve this limitation, each smp_ops
implementation created a per-cpu variable that is manipulated with atomic
bitops. Since these lines will be contended they are optimialy marked as
shared_aligned and take a full cache line for each cpu. Distro kernels
may have 2 or 3 of these in their config, each taking per-cpu space
even though at most one will be in use.
This consolidation removes smp_message_recv and replaces the single call
actions cases with direct calls from the common message recognition loop.
The complicated debugger ipi case with its muxed crash handling code is
moved to debug_ipi_action which is now called from the demux code (instead
of the multi-message action calling smp_message_recv).
I put a call to reschedule_action to increase the likelyhood of correctly
merging the anticipated scheduler_ipi() hook coming from the scheduler
tree; that single required call can be inlined later.
The actual message decode is a copy of the old pseries xics code with its
memory barriers and cache line spacing, augmented with a per-cpu unsigned
long based on the book-e doorbell code. The optional data is set via a
callback from the implementation and is passed to the new cause-ipi hook
along with the logical cpu number. While currently only the doorbell
implemntation uses this data it should be almost zero cost to retrieve and
pass it -- it adds a single register load for the argument from the same
cache line to which we just completed a store and the register is dead
on return from the call. I extended the data element from unsigned int
to unsigned long in case some other code wanted to associate a pointer.
The doorbell check_self is replaced by a call to smp_muxed_ipi_resend,
conditioned on the CPU_DBELL feature. The ifdef guard could be relaxed
to CONFIG_SMP but I left it with BOOKE for now.
Also, the doorbell interrupt vector for book-e was not calling irq_enter
and irq_exit, which throws off cpu accounting and causes code to not
realize it is running in interrupt context. Add the missing calls.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The only user of MSG_ALL_BUT_SELF in the whole kernel tree is powerpc,
and it only uses it to start the debugger. Both debuggers always call
smp_send_debugger_break with MSG_ALL_BUT_SELF, and only mpic can do
anything more optimal than a loop over all online cpus, but all message
passing implementations have to code for this special delivery target.
Convert smp_send_debugger_break to take void and loop calling the smp_ops
message_pass function for each of the other cpus in the online cpumask.
Use raw_smp_processor_id() because we are either entering the debugger
or trying to start kdump and the additional warning it not useful were
it to trigger.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
commit c56e58537d breaks SMP support in PPC_47x chip.
secondary_ti must be set to current thread info before callin kick_cpu or else
start_secondary_47x will jump into void when trying to return to c-code.
In the current setup secondary_ti is initialized before the CPU idle task is started
and only the boot core will start. I am not sure this is the correct solution, but it
makes SMP possible in my chip.
Note! The HOTPLUG support probably need some fixing to, There is no trampoline code
available in head_44x.S - start_secondary_resume?
Signed-off-by: Kerstin Jonsson <kerstin.jonsson@ericsson.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Adapt new API.
Almost change is trivial. Most important change is the below line
because we plan to change task->cpus_allowed implementation.
- ctx->cpus_allowed = current->cpus_allowed;
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we start a cpu we use smp_ops->kick_cpu(), which currently
returns void, it should be able to fail. Convert it to return
int, and update all uses.
Convert all the current error cases to return -ENOENT, which is
what would eventually be returned by __cpu_up() currently when
it doesn't detect the cpu as coming up in time.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.
In order to do so we need a generic callback from the existing scheduler IPI.
This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.
BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
Instead of creating idle threads at boot for all possible CPUs, we
create them on demand, like x86 or ARM, and we properly call init_idle
to re-initialize an idle thread when a CPU was unplugged and is now
re-plugged.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Instead, keep it static, expose an accessor and use that from
the PowerMac code. Avoids easy namespace collisions and will
make it easier to consolidate with other implementations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This allows us to stop abusing smp_ops->setup_cpu() for cleanup
tasks that have to take place after the initial boot time CPU
bringup.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove the last remnants of cpu_enable(), everybody uses the normal
__cpu_up() path now
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is used by some "soft" hotplug implementations. I needs to
call idle_task_exit() when the CPU is going away, and we remove
the now no-longer needed set_cpu_online() and local_irq_enable()
which are handled by the return to start_secondary
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Various thing are torn down when a CPU is hot-unplugged. That CPU
is expected to go back to start_secondary when re-plugged to re
initialize everything, such as clock sources, maps, ...
Some implementations just return from cpu_die() callback
in the idle loop when the CPU is "re-plugged". This is not enough.
We fix it using a little asm trampoline which resets the stack
and calls back into start_secondary as if we were all fresh from
boot. The trampoline already existed on ppc64, but we add it for
ppc32
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These APIs take logical cpu number as input
Change cpu_first_thread_in_core() to cpu_first_thread_sibling()
Change cpu_last_thread_in_core() to cpu_last_thread_sibling()
These APIs convert core number (index) to logical cpu/thread numbers
Add cpu_first_thread_of_core(int core)
Changed cpu_thread_to_core() to cpu_core_index_of_thread(int cpu)
The goal is to make 'threads_per_core' accessible to the
pseries_energy module. Instead of making an API to read
threads_per_core, this is a higher level wrapper function to
convert from logical cpu number to core number.
The current APIs cpu_first_thread_in_core() and
cpu_last_thread_in_core() returns logical CPU number while
cpu_thread_to_core() returns core number or index which is
not a logical CPU number. The new APIs are now clearly named to
distinguish 'core number' versus first and last 'logical cpu
number' in that core.
The new APIs cpu_{first,last}_thread_sibling() work on
logical cpu numbers. While cpu_first_thread_of_core() and
cpu_core_index_of_thread() work on core index.
Example usage: (4 threads per core system)
cpu_first_thread_sibling(5) = 4
cpu_last_thread_sibling(5) = 7
cpu_core_index_of_thread(5) = 1
cpu_first_thread_of_core(1) = 4
cpu_core_index_of_thread() is used in cpu_to_drc_index() in the
module and cpu_first_thread_of_core() is used in
drc_index_to_cpu() in the module.
Make API changes to few callers. Export symbols for use in modules.
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, when CONFIG_VIRT_CPU_ACCOUNTING is enabled, we use the
PURR register for measuring the user and system time used by
processes, as well as other related times such as hardirq and
softirq times. This turns out to be quite confusing for users
because it means that a program will often be measured as taking
less time when run on a multi-threaded processor (SMT2 or SMT4 mode)
than it does when run on a single-threaded processor (ST mode), even
though the program takes longer to finish. The discrepancy is
accounted for as stolen time, which is also confusing, particularly
when there are no other partitions running.
This changes the accounting to use the timebase instead, meaning that
the reported user and system times are the actual number of real-time
seconds that the program was executing on the processor thread,
regardless of which SMT mode the processor is in. Thus a program will
generally show greater user and system times when run on a
multi-threaded processor than on a single-threaded processor.
On pSeries systems on POWER5 or later processors, we measure the
stolen time (time when this partition wasn't running) using the
hypervisor dispatch trace log. We check for new entries in the
log on every entry from user mode and on every transition from
kernel process context to soft or hard IRQ context (i.e. when
account_system_vtime() gets called). So that we can correctly
distinguish time stolen from user time and time stolen from system
time, without having to check the log on every exit to user mode,
we store separate timestamps for exit to user mode and entry from
user mode.
On systems that have a SPURR (POWER6 and POWER7), we read the SPURR
in account_system_vtime() (as before), and then apportion the SPURR
ticks since the last time we read it between scaled user time and
scaled system time according to the relative proportions of user
time and system time over the same interval. This avoids having to
read the SPURR on every kernel entry and exit. On systems that have
PURR but not SPURR (i.e., POWER5), we do the same using the PURR
rather than the SPURR.
This disables the DTL user interface in /sys/debug/kernel/powerpc/dtl
for now since it conflicts with the use of the dispatch trace log
by the time accounting code.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Simple cleanup by moving arch_sd_sibling_asym_packing from process.c to
smp.c to save an #ifdef CONFIG_SMP
No functionality change.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During CPU offline/online tests __cpu_up would flood the logs with
the following message:
Processor 0 found.
This provides no useful information to the user as there is no context
provided, and since the operation was a success (to this point) it is expected
that the CPU will come back online, providing all the feedback necessary.
Change the "Processor found" message to DBG() similar to other such messages in
the same function. Also, add an appropriate log level for the "Processor is
stuck" message.
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Fontenot <nfont@austin.ibm.com>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We already defined start_cpu_decrementer() to invoke decrementer for AP as
the following path:
start_secondary() -> secondary_cpu_time_init() -> start_cpu_decrementer()
So remove these incorrect codes introduced from commit:
e7f75ad0 powerpc/47x: Base ppc476 support
And actually we really should not enable decrementer before calling set_dec().
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since the decrementer and timekeeping code was moved over to using
the generic clockevents and timekeeping infrastructure, several
variables and functions have been obsolete and effectively unused.
This deletes them.
In particular, wakeup_decrementer() is no longer needed since the
generic code reprograms the decrementer as part of the process of
resuming the timekeeping code, which happens during sysdev resume.
Thus the wakeup_decrementer calls in the suspend_enter methods for
52xx platforms have been removed. The call in the powermac cpu
frequency change code has been replaced by set_dec(1), which will
cause a timer interrupt as soon as interrupts are enabled, and the
generic code will then reprogram the decrementer with the correct
value.
This also simplifies the generic_suspend_en/disable_irqs functions
and makes them static since they are not referenced outside time.c.
The preempt_enable/disable calls are removed because the generic
code has disabled all but the boot cpu at the point where these
functions are called, so we can't be moved to another cpu.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Configuring a powerpc 32 bit kernel for both SMP and SUSPEND turns on
CPU_HOTPLUG to enable disable_nonboot_cpus to be called by the common
suspend code. Previously the definition of cpu_die for ppc32 was in
the powermac platform code, causing it to be undefined if that platform
as not selected.
arch/powerpc/kernel/built-in.o: In function 'cpu_idle':
arch/powerpc/kernel/idle.c:98: undefined reference to 'cpu_die'
Move the code from setup_64 to smp.c and rename the power mac
versions to their specific names.
Note that this does not setup the cpu_die pointers in either
smp_ops (request a given cpu die) or ppc_md (make this cpu die),
for other platforms but there are generic versions in smp.c.
Reported-by: Matt Sealey <matt@genesi-usa.com>
Reported-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since the *_map cpumask variants are deprecated, change the comments to
instead refer to *_mask.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Dynamically allocate cpu_sibling_map and cpu_core_map cpumasks.
We don't need to set_cpu_online() the boot cpu in smp_prepare_boot_cpu,
init/main.c does it for us.
We also postpone setting of the boot cpu in cpu_sibling_map and cpu_core_map
until when the memory allocator is available (smp_prepare_cpus), similar
to x86.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use new cpumask_* functions, and dynamically allocate cpumask in fixup_irqs.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use the new cpumask_* functions and dynamically allocate the cpumask in
smp_cpus_done.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds the base support for the 476 processor. The code was
primarily written by Ben Herrenschmidt and Torez Smith, but I've been
maintaining it for a while.
The goal is to have a single binary that will run on 44x and 47x, but
we still have some details to work out. The biggest is that the L1 cache
line size differs on the two platforms, but it's currently a compile-time
option.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Torez Smith <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Use set_cpus_allowed_ptr rather than set_cpus_allowed.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression E1,E2;
@@
- set_cpus_allowed(E1, cpumask_of_cpu(E2))
+ set_cpus_allowed_ptr(E1, cpumask_of(E2))
@@
expression E;
identifier I;
@@
- set_cpus_allowed(E, I)
+ set_cpus_allowed_ptr(E, &I)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
m68k: rename global variable vmalloc_end to m68k_vmalloc_end
percpu: add missing per_cpu_ptr_to_phys() definition for UP
percpu: Fix kdump failure if booted with percpu_alloc=page
percpu: make misc percpu symbols unique
percpu: make percpu symbols in ia64 unique
percpu: make percpu symbols in powerpc unique
percpu: make percpu symbols in x86 unique
percpu: make percpu symbols in xen unique
percpu: make percpu symbols in cpufreq unique
percpu: make percpu symbols in oprofile unique
percpu: make percpu symbols in tracer unique
percpu: make percpu symbols under kernel/ and mm/ unique
percpu: remove some sparse warnings
percpu: make alloc_percpu() handle array types
vmalloc: fix use of non-existent percpu variable in put_cpu_var()
this_cpu: Use this_cpu_xx in trace_functions_graph.c
this_cpu: Use this_cpu_xx for ftrace
this_cpu: Use this_cpu_xx in nmi handling
this_cpu: Use this_cpu operations in RCU
this_cpu: Use this_cpu ops for VM statistics
...
Fix up trivial (famous last words) global per-cpu naming conflicts in
arch/x86/kvm/svm.c
mm/slab.c
Remove the CPU from the online map to prevent smp_call_function
from sending messages to a stopped CPU.
Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch updates percpu related symbols in powerpc such that percpu
symbols are unique and don't clash with local symbols. This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.
* arch/powerpc/kernel/perf_callchain.c: s/callchain/cpu_perf_callchain/
* arch/powerpc/kernel/setup-common.c: s/pvr/cpu_pvr/
* arch/powerpc/platforms/pseries/dtl.c: s/dtl/cpu_dtl/
* arch/powerpc/platforms/cell/interrupt.c: s/iic/cpu_iic/
Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org
Use the accessors rather than frobbing bits directly (the new versions
are const).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
We're weaning the core code off handing cpumask's around on-stack.
This introduces arch_send_call_function_ipi_mask(), and by defining
it, the old arch_send_call_function_ipi is defined by the core code.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The following commit introduced a compile error since it removed
the implementation of smp_85xx_basic_setup:
commit 77c0a700c1
Author: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri Aug 28 14:25:04 2009 +1000
powerpc: Properly start decrementer on BookE secondary CPUs
Make it so that smp_ops probe() and setup_cpu() can be set to NULL.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Time time taken for a single cpu online operation on a pseries machine
is as follows:
Dedicated LPAR (POWER6): ~220ms.
Shared LPAR (POWER5) : ~240ms.
Of this time, approximately 200ms is taken up by __cpu_up(). This is because
we poll every 200ms to check if the new cpu has notified it's presence
through the cpu_callin_map. We repeat this operation until the new cpu sets
the value in cpu_callin_map or 5 seconds elapse, whichever comes earlier.
However, using completion_structs instead of polling loops,
the time taken by the new processor to indicate it's presence has
found to be less than 1ms on pseries. This method however may not
work on all powerpc platforms due to the time-base synchronization code.
Keeping this in mind, we could reduce msleep polling interval from
200ms to 1ms while retaining the 5 second timeout.
With this, the time taken for a cpu online operation changes as follows:
Dedicated LPAR (POWER6): 20-25ms.
Shared LPAR (POWER5) : 60-80ms.
In both these cases, it was found that the code polls through the loop
only once indicating that 1ms is a reasonable value, atleast on pseries.
The code needs testing on other powerpc platforms.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Acked-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The old PowerSurge SMP (ie, dual or quad 604 machines) code has
numerous issues in modern world.
One is cpu_possible_map is set too late (the device-tree is bogus)
so we fail to allocate the interrupt stacks and crash. Another
problem is the fact the timebase is frozen by the bringup of the
second CPU so the delays in the generic code will hang, we need
to move some of the calling procedure to inside the powermac code.
This makes it boot again for me
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
x86: export vector_used_by_percpu_irq
x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
sched: nominate preferred wakeup cpu, fix
x86: fix lguest used_vectors breakage, -v2
x86: fix warning in arch/x86/kernel/io_apic.c
sched: fix warning in kernel/sched.c
sched: move test_sd_parent() to an SMP section of sched.h
sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
sched: activate active load balancing in new idle cpus
sched: bias task wakeups to preferred semi-idle packages
sched: nominate preferred wakeup cpu
sched: favour lower logical cpu number for sched_mc balance
sched: framework for sched_mc/smt_power_savings=N
sched: convert BALANCE_FOR_xx_POWER to inline functions
x86: use possible_cpus=NUM to extend the possible cpus allowed
x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
x86: update io_apic.c to the new cpumask code
x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
x86: xen: use smp_call_function_many()
x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
...
Fixed up trivial conflict in kernel/time/tick-sched.c manually
The smp code uses cache information to populate cpu_core_map; change
it to use common code for cache lookup.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
smp_hw_index isn't used on 64-bit, so move it from smp.c to
setup_32.c.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Impact: cleanup
Each SMP arch defines these themselves. Move them to a central
location.
Twists:
1) Some archs (m32, parisc, s390) set possible_map to all 1, so we add a
CONFIG_INIT_ALL_POSSIBLE for this rather than break them.
2) mips and sparc32 '#define cpu_possible_map phys_cpu_present_map'.
Those archs simply have phys_cpu_present_map replaced everywhere.
3) Alpha defined cpu_possible_map to cpu_present_map; this is tricky
so I just manipulate them both in sync.
4) IA64, cris and m32r have gratuitous 'extern cpumask_t cpu_possible_map'
declarations.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Mike Travis <travis@sgi.com>
Cc: ink@jurassic.park.msu.ru
Cc: rmk@arm.linux.org.uk
Cc: starvik@axis.com
Cc: tony.luck@intel.com
Cc: takata@linux-m32r.org
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: paulus@samba.org
Cc: schwidefsky@de.ibm.com
Cc: lethal@linux-sh.org
Cc: wli@holomorphy.com
Cc: davem@davemloft.net
Cc: jdike@addtoit.com
Cc: mingo@redhat.com
With the new generic smp call function helpers, I noticed the code in
smp_message_recv was a single function call in many cases. While
getting the message number from the ipi data is easy, we can reduce
the path length by a function and data-dependent switch by registering
seperate IPI actions for these simple calls.
Originally I left the ipi action array exposed, but then I realized the
registration code should be common too.
The three users each had their own name array, so I made a fourth
to convert all users to use a common one.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The comment in the code was asking "Do we have to do this?", and according
to x86 and s390 the answer is no, the scheduler will do it before calling
the arch hook.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Right now, there is no notifier that is called on a new cpu, before the new
cpu begins processing interrupts/softirqs.
Various kernel function would need that notification, e.g. kvm works around
by calling smp_call_function_single(), rcu polls cpu_online_map.
The patch adds a CPU_STARTING notification. It also adds a helper function
that sends the message to all cpu_chain handlers.
Tested on x86-64.
All other archs are untested. Especially on sparc, I'm not sure if I got
it right.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Existing Open Firmware practice is to report each processor core as a
separate node in the device tree. Report the value of the "reg" OF
property corresponding to a logical CPU's device node as the core_id
attribute in /sys/devices/system/cpu/cpu*/topology/core_id.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Implement the notion of "core siblings" for powerpc. This makes
/sys/devices/system/cpu/cpu*/topology/core_siblings present sensible
values, indicating online CPUs which share an L2 cache.
BenH: Made cpu_to_l2cache() use of_find_node_by_phandle() instead
of IBM-specific open coded search
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather doing one initialization pass over all the per-cpu
cpu_sibling_maps at boot, update the maps at cpu online/offline time.
This is a behavior change -- the thread_siblings attribute now
reflects only online siblings, whereas it would display offline
siblings before. The new behavior matches that of x86, and is
arguably more useful.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This converts ppc to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().
ppc loses the timeout functionality of smp_call_function_mask() with
this change, as the generic code does not provide that.
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Make a few things static in lparcfg.c
Make init and exit routines static in rtas_flash.c
Make things static in rtas_pci.c
Make some functions static in rtas.c
Make fops static in rtas-proc.c
Remove unneeded extern for do_gtod in smp.c
Make clocksource_init() static in time.c
Make last_tick_len and ticklen_to_xs static in time.c
Move the declaration of the pvr per-cpu into smp.h
Make kexec_smp_down() and kexec_stack static in machine_kexec_64.c
Don't return void in arch_teardown_msi_irqs() in msi.c
Move declaration of GregorianDay()into asm/time.h
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a regression reported by Kamalesh Bulabel where a POWER4
machine would crash because of an SLB miss at a point where the SLB
miss exception was unrecoverable. This regression is tracked at:
http://bugzilla.kernel.org/show_bug.cgi?id=10082
SLB misses at such points shouldn't happen because the kernel stack is
the only memory accessed other than things in the first segment of the
linear mapping (which is mapped at all times by entry 0 of the SLB).
The context switch code ensures that SLB entry 2 covers the kernel
stack, if it is not already covered by entry 0. None of entries 0
to 2 are ever replaced by the SLB miss handler.
Where this went wrong is that the context switch code assumes it
doesn't have to write to SLB entry 2 if the new kernel stack is in the
same segment as the old kernel stack, since entry 2 should already be
correct. However, when we start up a secondary cpu, it calls
slb_initialize, which doesn't set up entry 2. This is correct for
the boot cpu, where we will be using a stack in the kernel BSS at this
point (i.e. init_thread_union), but not necessarily for secondary
cpus, whose initial stack can be allocated anywhere. This doesn't
cause any immediate problem since the SLB miss handler will just
create an SLB entry somewhere else to cover the initial stack.
In fact it's possible for the cpu to go quite a long time without SLB
entry 2 being valid. Eventually, though, the entry created by the SLB
miss handler will get overwritten by some other entry, and if the next
access to the stack is at an unrecoverable point, we get the crash.
This fixes the problem by making slb_initialize create a suitable
entry for the kernel stack, if we are on a secondary cpu and the stack
isn't covered by SLB entry 0. This requires initializing the
get_paca()->kstack field earlier, so I do that in smp_create_idle
where the current field is initialized. This also abstracts a bit of
the computation that mk_esid_data in slb.c does so that it can be used
in slb_initialize.
Signed-off-by: Paul Mackerras <paulus@samba.org>
smp_send_stop() will send an IPI to all other cpus to shut them down.
However, for the case of xmon-based reboots (as well as potentially some
panics), the other cpus are (or might be) spinning with interrupts off,
and won't take the IPI.
Current code will drop us into the debugger when the IPI fails, which
means we're in an infinite loop that we can't get out of without an
external reset of some sort.
Instead, make the smp_send_stop() IPI call path just print the warning
about being unable to send IPIs, but make it return so the rest of the
shutdown sequence can continue. It's not perfect, but the lesser of
two evils.
Also move the call_lock handling outside of smp_call_function_map so we
can avoid deadlocks in smp_send_stop().
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
smp_call_function_map should be static, and for consistency prepend it
with __ like other local helper functions in the same file.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Convert cpu_sibling_map from a static array sized by NR_CPUS to a per_cpu
variable. This saves sizeof(cpumask_t) * NR unused cpus. Access is mostly
from startup and CPU HOTPLUG functions.
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This registers a clock event structure for the decrementer and turns
on CONFIG_GENERIC_CLOCKEVENTS, which means that we now don't need
most of timer_interrupt(), since the work is done in generic code.
For secondary CPUs, their decrementer clockevent is registered when
the CPU comes up (the generic code automatically removes the
clockevent when the CPU goes down).
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
> ------------[ cut here ]------------
> Badness at arch/powerpc/kernel/smp.c:202
comes when smp_call_function_map() has been called with irqs disabled,
which is illegal. However, there is a special case, the panic() codepath,
when we do not want to warn about this -- warning at that time is pointless
anyway, and only serves to scroll away the *real* cause of the panic and
distracts from the real bug.
* So let's extract the WARN_ON() from smp_call_function_map() into all its
callers -- smp_call_function() and smp_call_function_single()
* Also, introduce another caller of smp_call_function_map(), namely
__smp_call_function() (and make smp_call_function() a wrapper over this)
which does *not* warn about disabled irqs
* Use this __smp_call_function() from the panic codepath's smp_send_stop()
We also end having to move code of smp_send_stop() below the definition
of __smp_call_function().
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In smp_call_function_map(), num_cpus is set to the number of online
CPUs minus one. However, if the CPU mask does not include all CPUs
(except the one we're running on), the routine will hang in the first
while() loop until the 8 second timeout occurs.
The num_cpus should be set to the number of CPUs specified in the mask
passed into the routine, after we've made any modifications to the
mask. With this change, we can also get rid of the call to
cpus_empty() and avoid adding another pass through the bitmask.
Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This removes the requirement for callers to get_cpu() to check in simple
cases. i386 and x86_64 already received a similar treatment.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
smp_call_function_map() was not safe against preemption to another
cpu: its test for removing self from map was outside the spinlock.
Rearrange it a little to fix that.
smp_call_function_single() was also wrong: now get_cpu() before
excluding self, as other architectures do.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add a new function named smp_call_function_single(). This matches a generic
prototype from include/linux/smp.h.
Add a function smp_call_function_map(). This is, for the most part, a rename
of smp_call_function, with some added cpumask support. smp_call_function and
smp_call_function_single call into smp_call_function_map.
Lightly tested on 970mp (blade), power4 and power5.
Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The current tlb flush code on powerpc 64 bits has a subtle race since we
lost the page table lock due to the possible faulting in of new PTEs
after a previous one has been removed but before the corresponding hash
entry has been evicted, which can leads to all sort of fatal problems.
This patch reworks the batch code completely. It doesn't use the mmu_gather
stuff anymore. Instead, we use the lazy mmu hooks that were added by the
paravirt code. They have the nice property that the enter/leave lazy mmu
mode pair is always fully contained by the PTE lock for a given range
of PTEs. Thus we can guarantee that all batches are flushed on a given
CPU before it drops that lock.
We also generalize batching for any PTE update that require a flush.
Batching is now enabled on a CPU by arch_enter_lazy_mmu_mode() and
disabled by arch_leave_lazy_mmu_mode(). The code epects that this is
always contained within a PTE lock section so no preemption can happen
and no PTE insertion in that range from another CPU. When batching
is enabled on a CPU, every PTE updates that need a hash flush will
use the batch for that flush.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Move a couple of MPIC smp routines into mpic.c, they're inside an SMP
block in mpic.c - so they're still only built for SMP.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Compiling the kernel with CONFIG_HOTPLUG = y and CONFIG_HOTPLUG_CPU = n
with CONFIG_RELOCATABLE = y generates the following modpost warnings
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141b7d) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141b9c) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.text:__cpu_up
from .text between '_cpu_up' (at offset 0xc0141bd8) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c05) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c26) and 'cpu_up'
WARNING: vmlinux - Section mismatch: reference to .init.data: from
.text between '_cpu_up' (at offset 0xc0141c37) and 'cpu_up'
This is because cpu_up, _cpu_up and __cpu_up (in some architectures) are
defined as __devinit
AND
__cpu_up calls some __cpuinit functions.
Since __cpuinit would map to __init with this kind of a configuration,
we get a .text refering .init.data warning.
This patch solves the problem by converting all of __cpu_up, _cpu_up
and cpu_up from __devinit to __cpuinit. The approach is justified since
the callers of cpu_up are either dependent on CONFIG_HOTPLUG_CPU or
are of __init type.
Thus when CONFIG_HOTPLUG_CPU=y, all these cpu up functions would land up
in .text section, and when CONFIG_HOTPLUG_CPU=n, all these functions would
land up in .init section.
Tested on a i386 SMP machine running linux-2.6.20-rc3-mm1.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds a cpufreq backend driver to enable frequency scaling on cell.
Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Pseudo-CHRP machines like Pegasos without an MPIC would crash at boot if
CONFIG_SMP was set because the "smp_ops" pointer was set to MPIC related
ops unconditionally. This patch makes it NULL on machines that don't
support SMP and provides proper default behaviour in the callers when
smp_ops is NULL.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Clear the high BATS during load_up_mmu if FTR_HAS_HIGH_BATS.
Allow just a bit more time for secondary CPUs to phone home.
Signed-off-by: Wei Zhang <Wei.Zhang@freescale.com>
Signed-off-by: Haiying Wang <Haiying.Wang@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.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>
This implements accurate task and cpu time accounting for 64-bit
powerpc kernels. Instead of accounting a whole jiffy of time to a
task on a timer interrupt because that task happened to be running at
the time, we now account time in units of timebase ticks according to
the actual time spent by the task in user mode and kernel mode. We
also count the time spent processing hardware and software interrupts
accurately. This is conditional on CONFIG_VIRT_CPU_ACCOUNTING. If
that is not set, we do tick-based approximate accounting as before.
To get this accurate information, we read either the PURR (processor
utilization of resources register) on POWER5 machines, or the timebase
on other machines on
* each entry to the kernel from usermode
* each exit to usermode
* transitions between process context, hard irq context and soft irq
context in kernel mode
* context switches.
On POWER5 systems with shared-processor logical partitioning we also
read both the PURR and the timebase at each timer interrupt and
context switch in order to determine how much time has been taken by
the hypervisor to run other partitions ("steal" time). Unfortunately,
since we need values of the PURR on both threads at the same time to
accurately calculate the steal time, and since we can only calculate
steal time on a per-core basis, the apportioning of the steal time
between idle time (time which we ceded to the hypervisor in the idle
loop) and actual stolen time is somewhat approximate at the moment.
This is all based quite heavily on what s390 does, and it uses the
generic interfaces that were added by the s390 developers,
i.e. account_system_time(), account_user_time(), etc.
This patch doesn't add any new interfaces between the kernel and
userspace, and doesn't change the units in which time is reported to
userspace by things such as /proc/stat, /proc/<pid>/stat, getrusage(),
times(), etc. Internally the various task and cpu times are stored in
timebase units, but they are converted to USER_HZ units (1/100th of a
second) when reported to userspace. Some precision is therefore lost
but there should not be any accumulating error, since the internal
accumulation is at full precision.
Signed-off-by: Paul Mackerras <paulus@samba.org>
When a cpu is hotplug-onlined, if we don't set per_cpu(last_jiffy) to
something sane, timer_interrupt will execute its while loop for every
tick missed since the cpu was last online (or since the system was
booted, if we're adding a new cpu). This can cause weird hangs, ssh
sessions dropping, and we can even go xmon if we take a global IPI at
the wrong time.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We used to print a NUMA cpu summary at boot before the hotplug cpu code
was added. This has been useful for catching machine configuration as
well as firmware bugs in the past.
This patch restores that functionality. An example of the output is:
Node 0 CPUs: 0-7
Node 1 CPUs: 8-15
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Implementing the machine_crash_shutdown which will be called by
crash_kexec (called in case of a panic, sysrq etc.). Disable the
interrupts, shootdown cpus using debugger IPI and collect regs
for all CPUs.
elfcorehdr= specifies the location of elf core header stored by
the crashed kernel. This command line option will be passed by
the kexec-tools to capture kernel.
savemaxmem= specifies the actual memory size that the first kernel
has and this value will be used for dumping in the capture kernel.
This command line option will be passed by the kexec-tools to
capture kernel.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch removes several unnecessary fields from the paca:
- next_jiffy_update_tb was simply unused. Remove trivially.
- The exdsi exception save area was not used. There were plans to use
it, but they never seem to have gone anywhere. If they ever do, we
can put it back. Remove from the paca, and from asm-offsets.c
- The default_decr field was used from asm, but was only ever assigned
the value of tb_ticks_per_jiffy. Just access tb_ticks_per_jiffy from
asm directly instead.
Built and booted on POWER5 LPAR and iSeries RS64.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
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>
Thomas Gleixner