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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="000000000000397449060938d25d" X-Rspam-User: X-Stat-Signature: apx3xtwiu111qgjc78kmm4y8rhjoihzb X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 01A63100011 X-HE-Tag: 1698989510-473749 X-HE-Meta: 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 GGf7aB0C kPKR28xH8GrRmDzRBc8mNRSaLohA5AYh6XAihcZ08Hlv08BMzooBvNN7rF0mjllxuDCaVxtWTZAU3YhMf/BryfrkZi/0hNtISrg/OQQ5HrP2EnsDYlHe2AG1z/hta2t2Oce171qKrxhlQXcwlTlY6perM7hycCs6ylKlQFb1mPDwmHcMoJo54NaSGhro9nBcPIyhxW9R5Qfq0pxtQdLAYIzL3/N8PoW9QMBBWhxRzjTYHPahwYkxDNpB420vlAw4zfrP6TyUd6VH2u5XC8jv7HRQXlDbkm3nhfGht6tRD99ETg3Xz7RePxWTzrmfk8QlNHdsluRy5m972aPGrxWpfXaczq90mXJjeCj0eOsd6SxO2flBh2F2mdEvei4kmmqBcwPs8yMgwiBQFly2y6+qbNGQRPb0DJ66qI/DWDztbHCtHluFektrqxpPKSQOLU3jJHps4ba75NH9cI1mMPDCDaIK+fdZcxAdlmkTJwEqD+ULIn/KYijRjhZLhxopLNJ5QUFfKQP3gHq58+PrUWKfVCkEjg2MPt/WrWu7H/DfHW51gJha+2awS6YqXLOI0uPC/ZlvVRAhT3zC1MeRlE9m08ksutzbM44KlyLcsWUAjRzjgDxaP6cClEriVWw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.020952, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: --000000000000397449060938d25d 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. 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. > --000000000000397449060938d25d 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 and end less than re= nd.

Mike Rapoport <rppt@k= ernel.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.
--000000000000397449060938d25d--