From: David Laight <David.Laight@ACULAB.COM>
To: 'Zhen Lei' <thunder.leizhen@huawei.com>,
Josh Poimboeuf <jpoimboe@kernel.org>,
Jiri Kosina <jikos@kernel.org>, Miroslav Benes <mbenes@suse.cz>,
Petr Mladek <pmladek@suse.com>,
Joe Lawrence <joe.lawrence@redhat.com>,
"live-patching@vger.kernel.org" <live-patching@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Masahiro Yamada <masahiroy@kernel.org>,
Alexei Starovoitov <ast@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
Kees Cook <keescook@chromium.org>,
Andrew Morton <akpm@linux-foundation.org>,
"Luis Chamberlain" <mcgrof@kernel.org>,
"linux-modules@vger.kernel.org" <linux-modules@vger.kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
"Ingo Molnar" <mingo@redhat.com>
Subject: RE: [PATCH v8 4/9] kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[]
Date: Wed, 2 Nov 2022 12:00:51 +0000 [thread overview]
Message-ID: <bd30cbc9b7594261a7b9da26e9c98da4@AcuMS.aculab.com> (raw)
In-Reply-To: <20221102084921.1615-5-thunder.leizhen@huawei.com>
From: Zhen Lei
> Sent: 02 November 2022 08:49
>
> kallsyms_seqs_of_names[] records the symbol index sorted by address, the
> maximum value in kallsyms_seqs_of_names[] is the number of symbols. And
> 2^24 = 16777216, which means that three bytes are enough to store the
> index. This can help us save (1 * kallsyms_num_syms) bytes of memory.
You can get the compiler to do the 'heavy lifting' for you.
struct uint24 {
unsigned int val24:24;
} __attribute__((packed));
struct uint24 table[1024];
works fine.
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
next prev parent reply other threads:[~2022-11-02 12:01 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-02 8:49 [PATCH v8 0/9] kallsyms: Optimizes the performance of lookup symbols Zhen Lei
2022-11-02 8:49 ` [PATCH v8 1/9] scripts/kallsyms: rename build_initial_tok_table() Zhen Lei
2022-11-02 8:49 ` [PATCH v8 2/9] kallsyms: Improve the performance of kallsyms_lookup_name() Zhen Lei
2022-11-02 8:49 ` [PATCH v8 3/9] kallsyms: Correctly sequence symbols when CONFIG_LTO_CLANG=y Zhen Lei
2022-11-02 8:49 ` [PATCH v8 4/9] kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] Zhen Lei
2022-11-02 12:00 ` David Laight [this message]
2022-11-07 8:01 ` Leizhen (ThunderTown)
2022-11-02 8:49 ` [PATCH v8 5/9] kallsyms: Add helper kallsyms_on_each_match_symbol() Zhen Lei
2022-11-02 8:49 ` [PATCH v8 6/9] livepatch: Use kallsyms_on_each_match_symbol() to improve performance Zhen Lei
2022-11-23 13:28 ` Petr Mladek
2022-11-24 2:36 ` Leizhen (ThunderTown)
2022-11-24 8:29 ` Petr Mladek
2022-12-06 22:08 ` Luis Chamberlain
2022-12-07 1:30 ` Leizhen (ThunderTown)
2022-11-02 8:49 ` [PATCH v8 7/9] livepatch: Improve the search performance of module_kallsyms_on_each_symbol() Zhen Lei
2022-11-14 7:47 ` Jiri Olsa
2022-11-14 8:50 ` Leizhen (ThunderTown)
2022-11-14 9:27 ` Jiri Olsa
2022-11-14 10:00 ` Leizhen (ThunderTown)
2022-11-14 10:31 ` Jiri Olsa
2022-11-14 11:30 ` Leizhen (ThunderTown)
2022-11-14 13:26 ` Jiri Olsa
2022-11-14 15:46 ` Luis Chamberlain
2022-11-15 2:10 ` Leizhen (ThunderTown)
2022-11-15 7:30 ` Jiri Olsa
2022-11-15 7:54 ` Luis Chamberlain
2022-11-15 8:14 ` Leizhen (ThunderTown)
2022-11-15 20:11 ` Stephen Rothwell
2022-11-23 13:57 ` Petr Mladek
2022-11-24 2:41 ` Leizhen (ThunderTown)
2022-11-02 8:49 ` [PATCH v8 8/9] kallsyms: Delete an unused parameter related to kallsyms_on_each_symbol() Zhen Lei
2022-11-02 8:49 ` [PATCH v8 9/9] kallsyms: Add self-test facility Zhen Lei
2022-11-13 2:44 ` [PATCH v8 0/9] kallsyms: Optimizes the performance of lookup symbols Luis Chamberlain
2022-11-13 2:55 ` Luis Chamberlain
2022-11-14 1:25 ` Leizhen (ThunderTown)
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=bd30cbc9b7594261a7b9da26e9c98da4@AcuMS.aculab.com \
--to=david.laight@aculab.com \
--cc=akpm@linux-foundation.org \
--cc=ast@kernel.org \
--cc=jikos@kernel.org \
--cc=joe.lawrence@redhat.com \
--cc=jolsa@kernel.org \
--cc=jpoimboe@kernel.org \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-modules@vger.kernel.org \
--cc=live-patching@vger.kernel.org \
--cc=masahiroy@kernel.org \
--cc=mbenes@suse.cz \
--cc=mcgrof@kernel.org \
--cc=mingo@redhat.com \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=thunder.leizhen@huawei.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