From: David Laight <David.Laight@ACULAB.COM>
To: 'Guo Ren' <guoren@kernel.org>, Leonardo Bras <leobras@redhat.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"paul.walmsley@sifive.com" <paul.walmsley@sifive.com>,
"palmer@dabbelt.com" <palmer@dabbelt.com>,
"alexghiti@rivosinc.com" <alexghiti@rivosinc.com>,
"charlie@rivosinc.com" <charlie@rivosinc.com>,
"xiao.w.wang@intel.com" <xiao.w.wang@intel.com>,
"david@redhat.com" <david@redhat.com>,
"panqinglin2020@iscas.ac.cn" <panqinglin2020@iscas.ac.cn>,
"rick.p.edgecombe@intel.com" <rick.p.edgecombe@intel.com>,
"willy@infradead.org" <willy@infradead.org>,
"bjorn@rivosinc.com" <bjorn@rivosinc.com>,
"conor.dooley@microchip.com" <conor.dooley@microchip.com>,
"cleger@rivosinc.com" <cleger@rivosinc.com>,
"linux-riscv@lists.infradead.org"
<linux-riscv@lists.infradead.org>,
Guo Ren <guoren@linux.alibaba.com>
Subject: RE: [PATCH V2 4/4] riscv: mm: Optimize TASK_SIZE definition
Date: Fri, 22 Dec 2023 11:52:39 +0000 [thread overview]
Message-ID: <e3f1521a9f04463587d07d0c99534d5a@AcuMS.aculab.com> (raw)
In-Reply-To: <CAJF2gTTX7AjexoRUw=ZS34HEWno7H3zvnXA+Q7TYsztNU=k2cg@mail.gmail.com>
From: Guo Ren
> Sent: 22 December 2023 11:25
...
> > > +#define TASK_SIZE (is_compat_task() ? \
> > > TASK_SIZE_32 : TASK_SIZE_64)
> I would remove is_compat_task() in the next version because your patch
> contains that.
Does TASK_SIZE get used in access_ok() ?
If so the repeated expansion of that 'mess' will slow things down.
OTOH access_ok(ptr, len) can just check (ptr | (ptr + len)) < 0)
and rely on the page faults for everything else.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
next prev parent reply other threads:[~2023-12-22 11:52 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-21 15:46 [PATCH V2 0/4] riscv: mm: Fixup & Optimize COMPAT code guoren
2023-12-21 15:46 ` [PATCH V2 1/4] riscv: mm: Fixup compat mode boot failure guoren
2023-12-22 1:51 ` Leonardo Bras
2023-12-22 2:57 ` Guo Ren
2023-12-22 3:50 ` Charlie Jenkins
2023-12-22 4:32 ` Leonardo Bras
2023-12-22 7:33 ` Guo Ren
2023-12-22 10:58 ` Guo Ren
2023-12-21 15:46 ` [PATCH V2 2/4] riscv: mm: Fixup compat arch_get_mmap_end guoren
2023-12-22 3:34 ` Leonardo Bras
2023-12-22 4:04 ` Charlie Jenkins
2023-12-22 4:23 ` Leonardo Bras
2023-12-22 5:42 ` Charlie Jenkins
2023-12-22 8:27 ` Leonardo Bras
2023-12-22 4:36 ` Guo Ren
2023-12-22 4:26 ` Guo Ren
2023-12-22 4:43 ` Leonardo Bras
2023-12-22 4:50 ` Guo Ren
2023-12-22 5:27 ` Leonardo Bras
2023-12-22 7:20 ` Guo Ren
2023-12-22 7:49 ` Leonardo Bras
2023-12-22 8:59 ` David Laight
2023-12-22 9:33 ` Guo Ren
2023-12-21 15:47 ` [PATCH V2 3/4] riscv: mm: Remove unused TASK_SIZE_MIN guoren
2023-12-22 4:49 ` Leonardo Bras
2023-12-22 7:16 ` Guo Ren
2023-12-22 7:22 ` Leonardo Bras
2023-12-21 15:47 ` [PATCH V2 4/4] riscv: mm: Optimize TASK_SIZE definition guoren
2023-12-22 5:09 ` Leonardo Bras
2023-12-22 11:25 ` Guo Ren
2023-12-22 11:52 ` David Laight [this message]
2023-12-23 2:38 ` Guo Ren
2023-12-23 2:52 ` Guo Ren
2023-12-23 10:31 ` David Laight
2023-12-24 1:24 ` Guo Ren
2023-12-24 14:37 ` David Laight
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=e3f1521a9f04463587d07d0c99534d5a@AcuMS.aculab.com \
--to=david.laight@aculab.com \
--cc=alexghiti@rivosinc.com \
--cc=bjorn@rivosinc.com \
--cc=charlie@rivosinc.com \
--cc=cleger@rivosinc.com \
--cc=conor.dooley@microchip.com \
--cc=david@redhat.com \
--cc=guoren@kernel.org \
--cc=guoren@linux.alibaba.com \
--cc=leobras@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=palmer@dabbelt.com \
--cc=panqinglin2020@iscas.ac.cn \
--cc=paul.walmsley@sifive.com \
--cc=rick.p.edgecombe@intel.com \
--cc=willy@infradead.org \
--cc=xiao.w.wang@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®