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To: Mike Rapoport Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Liangliang Huang Content-Type: multipart/alternative; boundary="000000000000f446c5060936fa45" X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 650CA80010 X-Stat-Signature: a1bq3ecpodq16fepbxbu76kmnyd5ri46 X-HE-Tag: 1698981604-377583 X-HE-Meta: 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 HX/vW3tp iSIlDZ23MoKxMUQx7eDDSev+6Hkg+udYqFi7mBBmKyxtzTLJAP+Lu88LrV+f+P4NQkdNwGT4KUEXHAKHkEz4LsEDfhXRSseahN9kDxC5oq0pVIYs/m8sik8XMeuPpmz5FAUiyzArokxIL7pB0z45jcL1i/xWfAogDZcJzezp7+dLsnBt1zEOf3N6D0zjng28fiU5isH9IIXHoNK0yeGBEI8nj7murThU1dLH2avQhFK5EZWshIMEsEdiiG28jeTzculzFrbGKfJwmMzxrDotcOg+/spjDQgcBU1V13JTOHKfbd05JMyyZlSYem1dugpN98bYkzKcjlT2kDL/e2Th6qxbtYeHnIJosqA5qcCNHcEuxSRgBJhtBZ4j9fhTLLa386JHAlMagOKQHpzAXkuv6t33kYVzUDz9ZmmBV58w0X/hKNDXjU1dWUfDnbPS4ZYpXtZ+h6wBPHj9R47l2eegvnNbsZ/IontCu8RoqSzbWgbrq5Bql7Az1Ow7aPKwCWcI2Fw++766MnFl+LPl39lJJUOMYFZ0IvHUMsHMPLDd+XhgFjBYWPbhsdTh6epkGkv5vwCDm+t+jNL9ovveLdOSx0i16wYX+WJfLZ+e6bAQLLpoVxLbP/ls5+8oISw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.076453, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: --000000000000f446c5060936fa45 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi, this patch can less loop once in this situation: base more than rbase and end less than rend. base end rbase----|-------------| --------rend | | | | ---------------------------------------------------> Mike Rapoport =E4=BA=8E2023=E5=B9=B411=E6=9C=882=E6=97=A5= =E5=91=A8=E5=9B=9B 16:54=E5=86=99=E9=81=93=EF=BC=9A > Hi, > > > Subject: [PATCH] mm/memblock.c: using judgment statement can reduce loo= p > and enhance readability. > > I disagree. > > On Thu, Nov 02, 2023 at 10:37:10AM +0800, huanglllzu@gmail.com wrote: > > From: Liangliang Huang > > > > Signed-off-by: Liangliang Huang > > --- > > mm/memblock.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/mm/memblock.c b/mm/memblock.c > > index 913b2520a9a0..e48dea7144bb 100644 > > --- a/mm/memblock.c > > +++ b/mm/memblock.c > > @@ -655,7 +655,11 @@ static int __init_memblock > memblock_add_range(struct memblock_type *type, > > } > > } > > /* area below @rend is dealt with, forget about it */ > > - base =3D min(rend, end); > > + if (end < rend) { > > + base =3D end; > > + break; > > + } else > > + base =3D rend; > > min() is perfectly clear and there no change in number of iterations of t= he > loop. > > > } > > > > /* insert the remaining portion */ > > -- > > 2.25.1 > > > > -- > Sincerely yours, > Mike. > --000000000000f446c5060936fa45 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi, this patch can = less loop once in this situation:
base more than rbase=C2=A0 and = end less than rend.
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 base=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 end
=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0 rbase----|-------------| --------rend
=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 | =C2=A0=C2=A0 =C2=A0 =C2=A0=C2=A0= =C2=A0 | =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 |=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 |
=C2=A0= --------------------------------------------------->
<= br>
Mike Ra= poport <rppt@kernel.org> =E4= =BA=8E2023=E5=B9=B411=E6=9C=882=E6=97=A5=E5=91=A8=E5=9B=9B 16:54=E5=86=99= =E9=81=93=EF=BC=9A
Hi,

> Subject: [PATCH] mm/memblock.c: using judgment statement can reduce lo= op and enhance readability.

I disagree.

On Thu, Nov 02, 2023 at 10:37:10AM +0800, huanglllzu@gmail.com wrote:
> From: Liangliang Huang <huangll@lemote.com>
>
> Signed-off-by: Liangliang Huang <huangll@lemote.com>
> ---
>=C2=A0 mm/memblock.c | 6 +++++-
>=C2=A0 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 913b2520a9a0..e48dea7144bb 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -655,7 +655,11 @@ static int __init_memblock memblock_add_range(str= uct memblock_type *type,
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0}
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0}
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0/* area below @r= end is dealt with, forget about it */
> -=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0base =3D min(rend, en= d);
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0if (end < rend) {<= br> > +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0= =C2=A0base =3D end;
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0= =C2=A0break;
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0} else
> +=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0= =C2=A0base =3D rend;

min() is perfectly clear and there no change in number of iterations of the=
loop.

>=C2=A0 =C2=A0 =C2=A0 =C2=A0}
>=C2=A0
>=C2=A0 =C2=A0 =C2=A0 =C2=A0/* insert the remaining portion */
> --
> 2.25.1
>

--
Sincerely yours,
Mike.
--000000000000f446c5060936fa45--