From: Johannes Berg <johannes@sipsolutions.net>
To: Tiwei Bie <tiwei.bie@linux.dev>,
richard@nod.at, anton.ivanov@cambridgegreys.com
Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org,
benjamin@sipsolutions.net, arnd@arndb.de,
tiwei.btw@antgroup.com
Subject: Re: [PATCH v2 08/10] um: Add initial SMP support
Date: Thu, 11 Sep 2025 11:32:56 +0200 [thread overview]
Message-ID: <03cb4661a6135a641c5a3779f2cb424356b8e345.camel@sipsolutions.net> (raw)
In-Reply-To: <20250810055136.897712-9-tiwei.bie@linux.dev> (sfid-20250810_075311_619208_642A3A1A)
On Sun, 2025-08-10 at 13:51 +0800, Tiwei Bie wrote:
> From: Tiwei Bie <tiwei.btw@antgroup.com>
>
> Add initial symmetric multi-processing (SMP) support to UML. With
> this support enabled, users can tell UML to start multiple virtual
> processors, each represented as a separate host thread.
>
> In UML, kthreads and normal threads (when running in kernel mode)
> can be scheduled and executed simultaneously on different virtual
> processors. However, the userspace code of normal threads still
> runs within their respective single-threaded stubs.
>
> That is, SMP support is currently available both within the kernel
> and across different processes, but still remains limited within
> threads of the same process in userspace.
Another thing that isn't covered is anything relating to interrupt
affinity, I guess? Is that automatically not working, or will it look
like you can change things but that not do anything?
I don't think it's important now (though eventually I would actually
like to have it for our simulations), but was just thinking about it.
johannes
next prev parent reply other threads:[~2025-09-11 9:33 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-10 5:51 [PATCH v2 00/10] um: Add SMP support Tiwei Bie
2025-08-10 5:51 ` [PATCH v2 01/10] um: Stop tracking virtual CPUs via mm_cpumask() Tiwei Bie
2025-08-10 5:51 ` [PATCH v2 02/10] um: Remove unused cpu_data and current_cpu_data macros Tiwei Bie
2025-08-10 5:51 ` [PATCH v2 03/10] um: vdso: Implement __vdso_getcpu() via syscall Tiwei Bie
2025-09-10 11:59 ` Johannes Berg
2025-09-11 4:29 ` Tiwei Bie
2025-09-21 20:00 ` Thomas Weißschuh
2025-09-22 4:50 ` Tiwei Bie
2025-09-22 12:05 ` Thomas Weißschuh
2025-09-22 12:12 ` Johannes Berg
2025-09-22 14:01 ` Thomas Weißschuh
2025-09-22 15:14 ` Johannes Berg
2025-09-22 16:04 ` Thomas Weißschuh
2025-09-22 17:07 ` Johannes Berg
2025-09-25 17:08 ` Thomas Weißschuh
2025-10-21 13:20 ` Johannes Berg
2025-08-10 5:51 ` [PATCH v2 04/10] um: Turn signals_* into thread-local variables Tiwei Bie
2025-09-10 12:15 ` Johannes Berg
2025-09-11 4:34 ` Tiwei Bie
2025-09-11 7:37 ` Benjamin Berg
2025-09-11 8:06 ` Benjamin Berg
2025-09-12 0:30 ` Tiwei Bie
2025-09-12 7:58 ` Benjamin Berg
2025-09-12 13:27 ` Tiwei Bie
2025-09-11 9:44 ` Johannes Berg
2025-09-11 10:35 ` Benjamin Berg
2025-08-10 5:51 ` [PATCH v2 05/10] um: Determine sleep based on need_resched() Tiwei Bie
2025-09-10 12:10 ` Johannes Berg
2025-09-11 4:39 ` Tiwei Bie
2025-09-11 6:59 ` Johannes Berg
2025-09-12 0:59 ` Tiwei Bie
2025-09-11 9:27 ` Johannes Berg
2025-09-12 0:54 ` Tiwei Bie
2025-08-10 5:51 ` [PATCH v2 06/10] um: Define timers on a per-CPU basis Tiwei Bie
2025-08-10 9:49 ` kernel test robot
2025-08-10 5:51 ` [PATCH v2 07/10] um: Remove unused ipi_pipe field from cpuinfo_um Tiwei Bie
2025-08-10 5:51 ` [PATCH v2 08/10] um: Add initial SMP support Tiwei Bie
2025-09-11 9:32 ` Johannes Berg [this message]
2025-09-12 0:45 ` Tiwei Bie
2025-09-12 7:58 ` Johannes Berg
2025-08-10 5:51 ` [PATCH v2 09/10] asm-generic: percpu: Add assembly guard Tiwei Bie
2025-09-10 12:12 ` Johannes Berg
2025-08-10 5:51 ` [PATCH v2 10/10] um: Enable SMP support on x86 Tiwei Bie
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=03cb4661a6135a641c5a3779f2cb424356b8e345.camel@sipsolutions.net \
--to=johannes@sipsolutions.net \
--cc=anton.ivanov@cambridgegreys.com \
--cc=arnd@arndb.de \
--cc=benjamin@sipsolutions.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-um@lists.infradead.org \
--cc=richard@nod.at \
--cc=tiwei.bie@linux.dev \
--cc=tiwei.btw@antgroup.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;
as well as URLs for NNTP newsgroup(s).