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| author | Naveen N. Rao | 2015-04-24 10:54:44 +0200 |
|---|---|---|
| committer | Michael Ellerman | 2015-08-06 08:36:23 +0200 |
| commit | 197165d44925bd0fa892990851dee4d312a44b39 (patch) | |
| tree | 5a3c35443e155b69a87456624ce458ee08a4ba08 /arch/powerpc/kernel/trace_clock.c | |
| parent | powerpc/4xx: Fix return value check in hsta_msi_probe() (diff) | |
| download | kernel-qcow2-linux-197165d44925bd0fa892990851dee4d312a44b39.tar.gz kernel-qcow2-linux-197165d44925bd0fa892990851dee4d312a44b39.tar.xz kernel-qcow2-linux-197165d44925bd0fa892990851dee4d312a44b39.zip | |
powerpc/ftrace: add powerpc timebase as a trace clock source
Add a new powerpc-specific trace clock using the timebase register,
similar to x86-tsc. This gives us
- a fast, monotonic, hardware clock source for trace entries, and
- a clock that can be used to correlate events across cpus as well as across
hypervisor and guests.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/trace_clock.c')
| -rw-r--r-- | arch/powerpc/kernel/trace_clock.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/trace_clock.c b/arch/powerpc/kernel/trace_clock.c new file mode 100644 index 000000000000..49170690946d --- /dev/null +++ b/arch/powerpc/kernel/trace_clock.c @@ -0,0 +1,15 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * Copyright (C) 2015 Naveen N. Rao, IBM Corporation + */ + +#include <asm/trace_clock.h> +#include <asm/time.h> + +u64 notrace trace_clock_ppc_tb(void) +{ + return get_tb(); +} |