On Wed, 2009-10-21 at 10:46 -0400, Steven Rostedt wrote:
> On Wed, 2009-10-21 at 22:34 +0800, Wu Zhangjin wrote:
> > This patch add the mips_timecounter_read() based high precision version
> > of trace_clock_local().
> >
> > Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
> > ---
> > arch/mips/kernel/Makefile | 6 ++++++
> > arch/mips/kernel/trace_clock.c | 37 +++++++++++++++++++++++++++++++++++++
> > 2 files changed, 43 insertions(+), 0 deletions(-)
> > create mode 100644 arch/mips/kernel/trace_clock.c
> >
> > diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
> > index 8e26e9c..f228868 100644
> > --- a/arch/mips/kernel/Makefile
> > +++ b/arch/mips/kernel/Makefile
> > @@ -8,6 +8,10 @@ obj-y += cpu-probe.o branch.o entry.o genex.o irq.o process.o \
> > ptrace.o reset.o setup.o signal.o syscall.o \
> > time.o topology.o traps.o unaligned.o watch.o
> >
> > +ifdef CONFIG_FUNCTION_TRACER
> > +CFLAGS_REMOVE_trace_clock.o = -pg
> > +endif
> > +
> > obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o
> > obj-$(CONFIG_CEVT_R4K_LIB) += cevt-r4k.o
> > obj-$(CONFIG_MIPS_MT_SMTC) += cevt-smtc.o
> > @@ -24,6 +28,8 @@ obj-$(CONFIG_SYNC_R4K) += sync-r4k.o
> > obj-$(CONFIG_STACKTRACE) += stacktrace.o
> > obj-$(CONFIG_MODULES) += mips_ksyms.o module.o
> >
> > +obj-$(CONFIG_FTRACE) += trace_clock.o
> > +
> > obj-$(CONFIG_CPU_LOONGSON2) += r4k_fpu.o r4k_switch.o
> > obj-$(CONFIG_CPU_MIPS32) += r4k_fpu.o r4k_switch.o
> > obj-$(CONFIG_CPU_MIPS64) += r4k_fpu.o r4k_switch.o
> > diff --git a/arch/mips/kernel/trace_clock.c b/arch/mips/kernel/trace_clock.c
> > new file mode 100644
> > index 0000000..2e3475f
> > --- /dev/null
> > +++ b/arch/mips/kernel/trace_clock.c
> > @@ -0,0 +1,37 @@
> > +/*
> > + * This file is subject to the terms and conditions of the GNU General Public
> > + * License. See the file "COPYING" in the main directory of this archive for
> > + * more details.
> > + *
> > + * Copyright (C) 2009 Lemote Inc. & DSLab, Lanzhou University, China
> > + * Author: Wu Zhangjin <wuzj@xxxxxxxxxx>
> > + */
> > +
> > +#include <linux/clocksource.h>
> > +#include <linux/sched.h>
> > +
> > +#include <asm/time.h>
> > +
> > +/*
> > + * trace_clock_local(): the simplest and least coherent tracing clock.
> > + *
> > + * Useful for tracing that does not cross to other CPUs nor
> > + * does it go through idle events.
> > + */
> > +u64 trace_clock_local(void)
> > +{
> > + unsigned long flags;
> > + u64 clock;
> > +
> > + raw_local_irq_save(flags);
> > +
> > + preempt_disable_notrace();
>
> Why have the preempt_disable? You disable interrupts already, that will
> prevent any preemption at that point.
>
just removed it.
Thanks!
Regards,
Wu Zhangjin
