The debug store selftest code uses a stack-allocated buffer, which is
not necessarily correctly aligned.

For tests using a buffer to hold a single entry, the buffer that is
passed to ds_request must already be suitably aligned.

Pass a suitably aligned portion of the bigger buffer.

[ Impact: fix hw-branch-tracer self-test failure ]
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: markus.t.metzger@gmail.com
LKML-Reference: <20090424094309.A30145@sedona.ch.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Check the buffer size more precisely to allow buffers for exactly
one element provided the base address is already properly aligned.

Add a debug store selftest.
Reported-by: NStephane Eranian <eranian@googlemail.com>
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144606.139137000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add selftests to cover per-task branch tracing.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144600.329346000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Perform debug store selftests on each cpu.

Cover both the normal and the _noirq variant of the debug store interface.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144559.394583000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix a bad bounds check in the debug store selftest.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144558.450027000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Size_t is defined differently on i386 and x86_64.
Change type to avoid compiler warning.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144557.523964000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The hw-branch-tracer uses debug store functions from an on_each_cpu()
context, which is simply wrong since the functions may sleep.

Add _noirq variants for most functions, which  may be called with
interrupts disabled.

Separate per-cpu and per-task tracing and allow per-cpu tracing to be
controlled from any cpu.

Make the hw-branch-tracer use the new debug store interface, synchronize
with hotplug cpu event using get/put_online_cpus(), and remove the
unnecessary spinlock.

Make the ptrace bts and the ds selftest code use the new interface.

Defer the ds selftest.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144555.658136000@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Perform a selftest of branch trace store when a cpu is initialized.

WARN and disable branch trace store support if the selftest fails.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090313104507.A30125@sedona.ch.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>