From: hekuang@huawei•com (Hekuang)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 2/2 v2] perf tools: Enable bpf prologue for arm64
Date: Fri, 3 Feb 2017 19:08:53 +0800 [thread overview]
Message-ID: <589464C5.5050205@huawei.com> (raw)
In-Reply-To: <20170126193122.GB17504@kernel.org>
hi,
? 2017/1/27 3:31, Arnaldo Carvalho de Melo ??:
> Em Thu, Jan 26, 2017 at 04:52:12PM +0000, Will Deacon escreveu:
>> On Thu, Jan 26, 2017 at 10:49:16AM +0900, Masami Hiramatsu wrote:
>>> On Wed, 25 Jan 2017 13:32:01 +0000
>>> Will Deacon <will.deacon@arm•com> wrote:
>>>
>>>> On Wed, Jan 25, 2017 at 07:23:11AM +0000, He Kuang wrote:
>>>>> Since HAVE_KPROBES can be enabled in arm64, this patch introduces
>>>>> regs_query_register_offset() to convert register name to offset for
>>>>> arm64, so the BPF prologue feature is ready to use.
>>>>>
>>>>> This patch also changes the 'dwarfnum' to 'offset' in register table,
>>>>> so the related functions are consistent with x86.
>>>> Wouldn't it be an awful lot simpler just to leave the code as-is, and
>>>> implement regs_query_register_offset in the same way that we implement
>>>> get_arch_regstr but return the dwarfnum?
>>> No, since the offset is not same as dwarfnum.
>>>
>>> With this style, the index of array becomes the dwarfnum (the index of
>>> each register defined by DWARF) and the "offset" member means the
>>> byte-offset of the register in (user_)pt_regs. Those should be different.
>> Ok, then do it as two patches then, rather than introduce functionality
>> along with the renaming.
>>
>>>> I don't really see the point of all the refactoring.
>>> Also, from the maintenance point of view, this rewrite work makes
>>> the code simply similar to x86 implementation, that will be easier to
>>> maintain :)
>> Right, apart from the two howling bugs in the version that was nearly merged
>> initially :p. I tend to err on the "if it ain't broke, don't fix it" side
>> of the argument but if you really want the refactoring lets keep it as a
>> separate change.
> So, He, can you do that? How do we proceed?
>
> - Arnaldo
I split the patch as Will suggested and resend them. Sorry for
late response, just back from Spring festival.
next prev parent reply other threads:[~2017-02-03 11:08 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20170124190908.GG10340@kernel.org>
2017-01-25 7:23 ` [PATCH 2/2 v2] perf tools: Enable bpf prologue for arm64 He Kuang
2017-01-25 13:32 ` Will Deacon
2017-01-26 1:49 ` Masami Hiramatsu
2017-01-26 16:52 ` Will Deacon
2017-01-26 19:31 ` Arnaldo Carvalho de Melo
2017-02-03 11:08 ` Hekuang [this message]
2017-01-26 1:51 ` Masami Hiramatsu
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=589464C5.5050205@huawei.com \
--to=hekuang@huawei$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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