linux.git/arch/powerpc/kernel/machine_kexec_64.c, branch v3.2

powerpc: Use for_each_node_by_type instead of open coding it

2011-09-20T05:53:23+00:00

Use for_each_node_by_type instead of open coding it.

Signed-off-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt

powerpc/kexec: Fix orphaned offline CPUs across kexec

2010-07-31T05:05:22+00:00

When CPU hotplug is used, some CPUs may be offline at the time a kexec is
performed.  The subsequent kernel may expect these CPUs to be already running,
and will declare them stuck.  On pseries, there's also a soft-offline (cede)
state that CPUs may be in; this can also cause problems as the kexeced kernel
may ask RTAS if they're online -- and RTAS would say they are.  The CPU will
either appear stuck, or will cause a crash as we replace its cede loop beneath
it.

This patch kicks each present offline CPU awake before the kexec, so that
none are forever lost to these assumptions in the subsequent kernel.

Now, the behaviour is that all available CPUs that were offlined are now
online & usable after the kexec.  This mimics the behaviour of a full reboot
(on which all CPUs will be restarted).

Signed-off-by: Matt Evans 
Signed-off-by: Benjamin Herrenschmidt

powerpc/kexec: Add to and tidy debug/comments in machine_kexec64.c

2010-07-31T05:05:21+00:00

Tidies some typos, KERN_INFO-ise an info msg, and add a debug msg showing
when the final sequence starts.

Also adds a comment to kexec_prepare_cpus_wait() to make note of a possible
problem; the need for kexec to deal with CPUs that failed to originally start
up.

Signed-off-by: Matt Evans 
Signed-off-by: Benjamin Herrenschmidt

powerpc/kexec: Switch to a static PACA on the way out

2010-07-31T04:56:30+00:00

With dynamic PACAs, the kexecing CPU's PACA won't lie within the kernel
static data and there is a chance that something may stomp it when preparing
to kexec.  This patch switches this final CPU to a static PACA just before
we pull the switch.

Signed-off-by: Matt Evans 
Signed-off-by: Benjamin Herrenschmidt

Merge commit 'paulus-perf/master' into next

2010-07-09T01:25:48+00:00

powerpc, hw_breakpoints: Implement hw_breakpoints for 64-bit server processors

2010-06-22T09:40:50+00:00

Implement perf-events based hw-breakpoint interfaces for PowerPC
64-bit server (Book III S) processors.  This allows access to a
given location to be used as an event that can be counted or
profiled by the perf_events subsystem.

This is done using the DABR (data breakpoint register), which can
also be used for process debugging via ptrace.  When perf_event
hw_breakpoint support is configured in, the perf_event subsystem
manages the DABR and arbitrates access to it, and ptrace then
creates a perf_event when it is requested to set a data breakpoint.

[Adopted suggestions from Paul Mackerras  to
- emulate_step() all system-wide breakpoints and single-step only the
  per-task breakpoints
- perform arch-specific cleanup before unregistration through
  arch_unregister_hw_breakpoint()
]

Signed-off-by: K.Prasad 
Signed-off-by: Paul Mackerras

powerpc/kexec: Wait for online/possible CPUs only.

2010-06-15T05:02:33+00:00

kexec_perpare_cpus_wait() iterates i through NR_CPUS to check
paca[i].kexec_state of each to make sure they have quiesced.
However now we have dynamic PACA allocation, paca[NR_CPUS] is not necessarily
valid and we overrun the array;  spurious "cpu is not possible, ignoring"
errors result.  This patch iterates for_each_online_cpu so stays
within the bounds of paca[] -- and every CPU is now 'possible'.

Signed-off-by: Matt Evans 
Signed-off-by: Benjamin Herrenschmidt

powerpc/kexec: Fix race in kexec shutdown

2010-05-21T07:31:11+00:00

In kexec_prepare_cpus, the primary CPU IPIs the secondary CPUs to
kexec_smp_down().  kexec_smp_down() calls kexec_smp_wait() which sets
the hw_cpu_id() to -1.  The primary does this while leaving IRQs on
which means the primary can take a timer interrupt which can lead to
the IPIing one of the secondary CPUs (say, for a scheduler re-balance)
but since the secondary CPU now has a hw_cpu_id = -1, we IPI CPU
-1... Kaboom!

We are hitting this case regularly on POWER7 machines.

There is also a second race, where the primary will tear down the MMU
mappings before knowing the secondaries have entered real mode.

Also, the secondaries are clearing out any pending IPIs before
guaranteeing that no more will be received.

This changes kexec_prepare_cpus() so that we turn off IRQs in the
primary CPU much earlier.  It adds a paca flag to say that the
secondaries have entered the kexec_smp_down() IPI and turned off IRQs,
rather than overloading hw_cpu_id with -1.  This new paca flag is
again used to in indicate when the secondaries has entered real mode.

It also ensures that all CPUs have their IRQs off before we clear out
any pending IPI requests (in kexec_cpu_down()) to ensure there are no
trailing IPIs left unacknowledged.

Signed-off-by: Michael Neuling 
Signed-off-by: Benjamin Herrenschmidt

Use new __init_task_data macro in arch init_task.c files.

2009-09-21T04:27:08+00:00

Signed-off-by: Joe Perches 
Signed-off-by: Tim Abbott 
Acked-by: Paul Mundt 
Signed-off-by: Sam Ravnborg

powerpc/32: Setup OF properties for kdump

2008-12-23T04:13:29+00:00

Refactor the setting of kdump OF properties, moving the common code
from machine_kexec_64.c to machine_kexec.c where it can be used on
both ppc64 and ppc32.  This will be needed for kdump to work on ppc32
platforms.

Signed-off-by: Dale Farnsworth 
Signed-off-by: Anton Vorontsov 
Signed-off-by: Paul Mackerras