From: Steven Rostedt <rostedt@goodmis.org>
To: Alan Kao <alankao@andestech.com>
Cc: Palmer Dabbelt <palmer@sifive.com>, Albert Ou <albert@sifive.com>,
<sw-dev@groups.riscv.org>, <linux-kernel@vger.kernel.org>,
<greentime@andestech.com>, <zong@andestech.com>
Subject: Re: ftrace: Proposal for an Alternative RecordMcount framework
Date: Tue, 27 Feb 2018 16:12:52 -0500 [thread overview]
Message-ID: <20180227161252.25162d81@vmware.local.home> (raw)
In-Reply-To: <20180227100425.GB20904@andestech.com>
On Tue, 27 Feb 2018 18:04:26 +0800
Alan Kao <alankao@andestech.com> wrote:
> 1. During the final linking stages, do "objdump vmlinux.o | grep ..." [2]
Note, doing it at that stage takes the longest time. It makes small
changes much longer to compile. That said...
> 2. Form the output as an ELF objecj
> 3. Link the object to __mcount_loc_start symbol
> 4. Done
>
> With the similar reason as the patch [3], we should mark _mcount to be
> a weak symbol to prevent it from being relaxed later.
>
> We would like to know your opinion and comments on this.
> Thanks!
What about just having your arch use recordmcount.c instead? It doesn't
do any grepping. It is an elf reader and modifier and modifies the .o
file directly.
Note, I will be rewriting that code in the near future too, to
consolidate it with objtool.
-- Steve
next prev parent reply other threads:[~2018-02-27 21:12 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-27 10:04 Alan Kao
2018-02-27 21:12 ` Steven Rostedt [this message]
2018-03-01 2:05 ` Alan Kao
2018-03-07 1:47 ` Alan Kao
2018-03-07 2:00 ` Steven Rostedt
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