On Fri, 30 Aug 2019 08:42:25 +0200
Michal Suchánek <msucha...@suse.de> wrote:
> On Fri, 30 Aug 2019 06:35:11 +0000 (UTC)
> Christophe Leroy <christophe.le...@c-s.fr> wrote:
>
> > On 08/29/2019 10:28 PM, Michal Suchanek wrote:
> > obj-$(CONFIG_PPC_PERF_CTRS) += core-book3s.o bhrb.o
> > diff --git a/arch/powerpc/perf/callchain_32.c
> > b/arch/powerpc/perf/callchain_32.c
> > index 0bd4484eddaa..17c43ae03084 100644
> > --- a/arch/powerpc/perf/callchain_32.c
> > +++ b/arch/powerpc/perf/callchain_32.c
> > @@ -15,50 +15,13 @@
> > #include <asm/sigcontext.h>
> > #include <asm/ucontext.h>
> > #include <asm/vdso.h>
> > -#ifdef CONFIG_PPC64
> > -#include "../kernel/ppc32.h"
> > -#endif
> > #include <asm/pte-walk.h>
> >
> > #include "callchain.h"
> >
> > #ifdef CONFIG_PPC64
> > -static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
> > -{
> > - if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
> > - ((unsigned long)ptr & 3))
> > - return -EFAULT;
> > -
> > - pagefault_disable();
> > - if (!__get_user_inatomic(*ret, ptr)) {
> > - pagefault_enable();
> > - return 0;
> > - }
> > - pagefault_enable();
> > -
> > - return read_user_stack_slow(ptr, ret, 4);
> > -}
> > -#else /* CONFIG_PPC64 */
> > -/*
> > - * On 32-bit we just access the address and let hash_page create a
> > - * HPTE if necessary, so there is no need to fall back to reading
> > - * the page tables. Since this is called at interrupt level,
> > - * do_page_fault() won't treat a DSI as a page fault.
> > - */
> > -static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
> > -{
> > - int rc;
> > -
> > - if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
> > - ((unsigned long)ptr & 3))
> > - return -EFAULT;
> > -
> > - pagefault_disable();
> > - rc = __get_user_inatomic(*ret, ptr);
> > - pagefault_enable();
> > -
> > - return rc;
> > -}
> > +#include "../kernel/ppc32.h"
> > +#else
> >
> > #define __SIGNAL_FRAMESIZE32 __SIGNAL_FRAMESIZE
> > #define sigcontext32 sigcontext
> > @@ -95,6 +58,30 @@ struct rt_signal_frame_32 {
> > int abigap[56];
> > };
> >
> > +/*
> > + * On 32-bit we just access the address and let hash_page create a
> > + * HPTE if necessary, so there is no need to fall back to reading
> > + * the page tables. Since this is called at interrupt level,
> > + * do_page_fault() won't treat a DSI as a page fault.
> > + */
> > +static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
> > +{
> > + int rc;
> > +
> > + if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
> > + ((unsigned long)ptr & 3))
> > + return -EFAULT;
> > +
> > + pagefault_disable();
> > + rc = __get_user_inatomic(*ret, ptr);
> > + pagefault_enable();
> > +
> > + if (IS_ENABLED(CONFIG_PPC32) || !rc)
> > + return rc;
> > +
> > + return read_user_stack_slow(ptr, ret, 4);
> > +}
> > +
> > static int is_sigreturn_32_address(unsigned int nip, unsigned int fp)
> > {
> > if (nip == fp + offsetof(struct signal_frame_32, mctx.mc_pad))
>
> I will leave consolidating this function to somebody who knows what the
> desired semantic is. With a short ifdef section at the top of the file
> it is a low-hanging fruit.
It looks ok if done as a separate patch.
Thanks
Michal
