Sorry I m not used yet at all to LKML rules.
So here a slight difference in assembly generated between the two
versions (amd64) :
`
.loc 1 7 7
leaq -12(%rbp), %rax
movq %rax, -8(%rbp)
- .loc 1 11 2
+ .loc 1 9 6
movq -8(%rbp), %rax
movl $4, %edx
movl $0, %esi
movq %rax, %rdi
call memset@PLT
+ movq %rax, -8(%rbp)
.loc 1 13 23
movq -8(%rbp), %rax
movl (%rax), %eax
`
On Mon, 26 Nov 2018 at 11:37, Joey Pabalinas <joeypabali...@gmail.com> wrote:
>
> On Sat, Nov 24, 2018 at 12:35:43PM +0000, David CARLIER wrote:
> > Using the return value of memset for save/load sake.
> >
> > Signed-off-by: David Carlier <devne...@gmail.com>
> > ---
> > lib/string.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/lib/string.c b/lib/string.c
> > index 38e4ca08e757..92da04a0213b 100644
> > --- a/lib/string.c
> > +++ b/lib/string.c
> > @@ -720,7 +720,7 @@ EXPORT_SYMBOL(memset);
> > */
> > void memzero_explicit(void *s, size_t count)
> > {
> > - memset(s, 0, count);
> > + s = memset(s, 0, count);
> > barrier_data(s);
> > }
> > EXPORT_SYMBOL(memzero_explicit);
>
> Could you elaborate on the optimization that this patch performs?
>
> --
> Cheers,
> Joey Pabalinas
