linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Masami Hiramatsu <mhiramat@kernel.org>
To: Borislav Petkov <bp@alien8.de>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [for-next][PATCH 04/26] bootconfig: Add Extra Boot Config support
Date: Sat, 8 Feb 2020 00:06:48 +0900	[thread overview]
Message-ID: <20200208000648.3383f991fee68af5ee229d65@kernel.org> (raw)
In-Reply-To: <20200207114122.GB24074@zn.tnic>

On Fri, 7 Feb 2020 12:41:22 +0100
Borislav Petkov <bp@alien8.de> wrote:

> On Fri, Feb 07, 2020 at 11:46:17AM +0900, Masami Hiramatsu wrote:
> > It could change some other things. I recommend developers to use this
> > feature to configure their subsystem easier and admins to configure
> > kernel boot options more readable way.
> 
> Well, I could use an actual justification for why I would need it.
> Because, frankly, I haven't sat down and thought: "hmm, this boot
> command line supplement thing is awful and I need a better one." IOW,
> it has never bothered me so far. But I'm always open to improvements as
> long as they don't make it worse. :)

OK, could you tell me your idea to make it better? I'm waiting for such
discussion a half of last year :)

For your information, here is the background of this bootconfig.
To build my boot-time tracing, I need a way to pass a flexible and
structured configuration at boot time.
I had tried to reuse devicetree at first, but it was rejected because
the devicetree is only for describing hardware. So I introduced this
bootconfig.
When I designed the bootconfig, I tried to sort out the requirements.
That config should be able to pass all setting we can do on tracefs.
Since ftrace already has a parser for tracefs, we don't need any types
for each settings. Thus it should be something like sysctl.conf. But the
sysctl.conf was too simple, it couldn't handle several related keys
well. So I decided to introduce braces which put together some related
parameters. And the bootconfig syntax was born.

I see that current piggyback method might look a bit odd. My first
implementation was bootloader based method (I implemented it on grub and
qemu), but that was not useful, especially it required user to replace
their bootloader...

> > Many distros may not use it unless it is default y. I couldn't find any
> > good example that the feature "default n" turns into "default y".
> > Would you have any example?
> 
> We - SUSE - always reevaluate our configs for the next service pack and
> enable things which make sense and customers use. So all the new drivers
> get enabled, kernel infra which makes sense too, etc.
> 
> If the bootconfig thing proves useful, I will glady enable it in our
> tree.

Okay, I hope it and try to prove it. Anyway, to use boot-time tracing which
can fully utilize ftrace at boot-time, we have to enable bootconfig.

Thank you,

-- 
Masami Hiramatsu <mhiramat@kernel.org>

  reply	other threads:[~2020-02-07 15:06 UTC|newest]

Thread overview: 65+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-14 21:03 [for-next][PATCH 00/26] tracing: Updates for 5.6 Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 01/26] perf: Make struct ring_buffer less ambiguous Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 02/26] tracing: Rename trace_buffer to array_buffer Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 03/26] tracing: Make struct ring_buffer less ambiguous Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 04/26] bootconfig: Add Extra Boot Config support Steven Rostedt
2020-02-06 11:54   ` Borislav Petkov
2020-02-06 14:41     ` Masami Hiramatsu
2020-02-06 17:20       ` Geert Uytterhoeven
2020-02-07  0:30         ` Masami Hiramatsu
2020-02-07  8:49           ` Geert Uytterhoeven
2020-02-07 13:17             ` Masami Hiramatsu
2020-02-07 14:28               ` [PATCH] bootconfig: Allocate xbc_nodes array dynamically Masami Hiramatsu
2020-02-06 17:58       ` [for-next][PATCH 04/26] bootconfig: Add Extra Boot Config support Borislav Petkov
2020-02-06 18:10         ` Randy Dunlap
2020-02-06 22:39           ` Steven Rostedt
2020-02-06 22:51             ` Borislav Petkov
2020-02-07  8:59             ` Geert Uytterhoeven
2020-02-07  2:46         ` Masami Hiramatsu
2020-02-07 11:41           ` Borislav Petkov
2020-02-07 15:06             ` Masami Hiramatsu [this message]
2020-02-10 11:25               ` Borislav Petkov
2020-02-10 15:10                 ` Masami Hiramatsu
2020-02-10 17:40                   ` Borislav Petkov
2020-02-11  2:02                     ` Masami Hiramatsu
2020-02-18 13:27                       ` Borislav Petkov
2020-02-18 17:57                         ` Steven Rostedt
2020-02-18 19:38                           ` Borislav Petkov
2020-02-19  2:26                             ` Masami Hiramatsu
2020-02-19  2:26                           ` Masami Hiramatsu
2020-02-19  2:26                         ` Masami Hiramatsu
2020-02-11  9:25                     ` Geert Uytterhoeven
2020-01-14 21:03 ` [for-next][PATCH 05/26] bootconfig: Load boot config from the tail of initrd Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 06/26] tools: bootconfig: Add bootconfig command Steven Rostedt
2020-02-07 13:02   ` Michael Ellerman
2020-02-07 13:39     ` Masami Hiramatsu
2020-02-07 13:55     ` [PATCH] tools/bootconfig: Fix wrong __VA_ARGS__ usage Masami Hiramatsu
2020-02-08 11:10       ` Michael Ellerman
2020-02-09  4:09         ` Masami Hiramatsu
2020-02-09 13:05         ` [PATCH] tools/bootconfig: Suppress non-error messages Masami Hiramatsu
2020-02-10  2:06           ` Michael Ellerman
2020-02-10  7:18             ` Masami Hiramatsu
2020-02-10  9:50               ` Michael Ellerman
2020-02-10  9:50       ` [PATCH] tools/bootconfig: Fix wrong __VA_ARGS__ usage Michael Ellerman
2020-02-10 17:07         ` Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 07/26] tools: bootconfig: Add bootconfig test script Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 08/26] proc: bootconfig: Add /proc/bootconfig to show boot config list Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 09/26] init/main.c: Alloc initcall_command_line in do_initcall() and free it Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 10/26] bootconfig: init: Allow admin to use bootconfig for kernel command line Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 11/26] bootconfig: init: Allow admin to use bootconfig for init " Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 12/26] Documentation: bootconfig: Add a doc for extended boot config Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 13/26] tracing: Apply soft-disabled and filter to tracepoints printk Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 14/26] tracing: kprobes: Output kprobe event to printk buffer Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 15/26] tracing: kprobes: Register to dynevent earlier stage Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 16/26] tracing: Accept different type for synthetic event fields Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 17/26] tracing: Add NULL trace-array check in print_synth_event() Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 18/26] tracing/boot: Add boot-time tracing Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 19/26] tracing/boot: Add per-event settings Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 20/26] tracing/boot Add kprobe event support Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 21/26] tracing/boot: Add synthetic " Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 22/26] tracing/boot: Add instance node support Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 23/26] tracing/boot: Add cpu_mask option support Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 24/26] tracing/boot: Add function tracer filter options Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 25/26] Documentation: tracing: Add boot-time tracing document Steven Rostedt
2020-01-14 21:03 ` [for-next][PATCH 26/26] tracing: trigger: Replace unneeded RCU-list traversals Steven Rostedt
2020-01-14 22:11   ` Steven Rostedt

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=20200208000648.3383f991fee68af5ee229d65@kernel.org \
    --to=mhiramat@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=bp@alien8.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=rostedt@goodmis.org \
    --subject='Re: [for-next][PATCH 04/26] bootconfig: Add Extra Boot Config support' \
    /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

This is a public inbox, see mirroring instructions
on how to clone and mirror all data and code used for this inbox