Re: [PATCH] hw_breakpoint: Fix build warnings with clang

[Ravi Bangoria]

On 6/2/20 4:30 PM, Michael Ellerman wrote:
> Christophe Leroy <christophe.leroy@xxxxxxxxxx> writes:
> > Le 02/06/2020 Ã 06:12, Ravi Bangoria a ÃcritÂ:
> > > kbuild test robot reported few build warnings with hw_breakpoint code
> > > when compiled with clang[1]. Fix those.
> > >
> > > [1]: https://lore.kernel.org/linuxppc-dev/202005192233.oi9CjRtA%25lkp@xxxxxxxxx/
>
> This should have mentioned that some of the errors were recently
> introduced by your commit.

Sure, will take care next time.

> > > Reported-by: kbuild test robot <lkp@xxxxxxxxx>
> > > Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
> > > ---
> > > Note: Prepared on top of powerpc/next.
> > >
> > >    arch/powerpc/include/asm/hw_breakpoint.h | 3 ---
> > >    include/linux/hw_breakpoint.h            | 4 ++++
> > >    2 files changed, 4 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
> > > index f42a55eb77d2..cb424799da0d 100644
> > > --- a/arch/powerpc/include/asm/hw_breakpoint.h
> > > +++ b/arch/powerpc/include/asm/hw_breakpoint.h
> > > @@ -70,9 +70,6 @@ extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
> > >    						unsigned long val, void *data);
> > >    int arch_install_hw_breakpoint(struct perf_event *bp);
> > >    void arch_uninstall_hw_breakpoint(struct perf_event *bp);
> > > -int arch_reserve_bp_slot(struct perf_event *bp);
> > > -void arch_release_bp_slot(struct perf_event *bp);
> > > -void arch_unregister_hw_breakpoint(struct perf_event *bp);
> > >    void hw_breakpoint_pmu_read(struct perf_event *bp);
> > >    extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
> > >    
> > > diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h
> > > index 6058c3844a76..521481f0d320 100644
> > > --- a/include/linux/hw_breakpoint.h
> > > +++ b/include/linux/hw_breakpoint.h
> > > @@ -80,6 +80,10 @@ extern int dbg_reserve_bp_slot(struct perf_event *bp);
> > >    extern int dbg_release_bp_slot(struct perf_event *bp);
> > >    extern int reserve_bp_slot(struct perf_event *bp);
> > >    extern void release_bp_slot(struct perf_event *bp);
> > > +extern int hw_breakpoint_weight(struct perf_event *bp);
> > > +extern int arch_reserve_bp_slot(struct perf_event *bp);
> > > +extern void arch_release_bp_slot(struct perf_event *bp);
> > > +extern void arch_unregister_hw_breakpoint(struct perf_event *bp);
> >
> > Please no new 'extern'. In the old days 'extern' keyword was used, but
> > new code shall not introduce new unnecessary usage of 'extern' keyword.
> > See report from Checkpatch below:
> >
> > WARNING:COMMIT_LOG_LONG_LINE: Possible unwrapped commit description
> > (prefer a maximum 75 chars per line)
> > #9:
> > [1]:
> > https://lore.kernel.org/linuxppc-dev/202005192233.oi9CjRtA%25lkp@xxxxxxxxx/
> >
> > CHECK:AVOID_EXTERNS: extern prototypes should be avoided in .h files
> > #40: FILE: include/linux/hw_breakpoint.h:83:
> > +extern int hw_breakpoint_weight(struct perf_event *bp);
>
> I fixed it up when applying.

Thanks Michael.

Ravi