lkml.org 
[lkml]   [2019]   [Aug]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v6 3/6] powerpc/perf: consolidate read_user_stack_32
From
Date


Le 30/08/2019 à 20:57, Michal Suchanek a écrit :
> There are two almost identical copies for 32bit and 64bit.
>
> The function is used only in 32bit code which will be split out in next
> patch so consolidate to one function.
>
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>

Reviewed-by: Christophe.Leroy@c-s.fr

> ---
> new patch in v6
> ---
> arch/powerpc/perf/callchain.c | 25 +++++++++----------------
> 1 file changed, 9 insertions(+), 16 deletions(-)
>
> diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c
> index c84bbd4298a0..b7cdcce20280 100644
> --- a/arch/powerpc/perf/callchain.c
> +++ b/arch/powerpc/perf/callchain.c
> @@ -165,22 +165,6 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
> return read_user_stack_slow(ptr, ret, 8);
> }
>
> -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);
> -}
> -
> static inline int valid_user_sp(unsigned long sp, int is_64)
> {
> if (!sp || (sp & 7) || sp > (is_64 ? TASK_SIZE : 0x100000000UL) - 32)
> @@ -295,6 +279,12 @@ static inline int current_is_64bit(void)
> }
>
> #else /* CONFIG_PPC64 */
> +static int read_user_stack_slow(void __user *ptr, void *buf, int nb)
> +{
> + return 0;
> +}
> +#endif /* 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
> @@ -313,9 +303,12 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
> rc = __get_user_inatomic(*ret, ptr);
> pagefault_enable();
>
> + if (IS_ENABLED(CONFIG_PPC64) && rc)
> + return read_user_stack_slow(ptr, ret, 4);
> return rc;
> }
>
> +#ifndef CONFIG_PPC64
> static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
> struct pt_regs *regs)
> {
>

\
 
 \ /
  Last update: 2019-08-30 22:22    [W:0.133 / U:4.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site