Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
MIME-Version: 1.0
References: <20230814132309.32641-1-rf@opensource.cirrus.com>
In-Reply-To: <20230814132309.32641-1-rf@opensource.cirrus.com>
From:   Rae Moar <rmoar@google.com>
Date:   Wed, 16 Aug 2023 15:57:24 -0400
Message-ID: <CA+GJov6dkLkeUE4nAW6BnY+75VAemqMxTE-na6SUrGqAz1ntWQ@mail.gmail.com>
Subject: Re: [PATCH v4 00/10] kunit: Add dynamically-extending log
To:     Richard Fitzgerald <rf@opensource.cirrus.com>
Cc:     brendan.higgins@linux.dev, davidgow@google.com,
        linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com,
        linux-kernel@vger.kernel.org, patches@opensource.cirrus.com
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Mon, Aug 14, 2023 at 9:23=E2=80=AFAM Richard Fitzgerald
<rf@opensource.cirrus.com> wrote:
>
> This patch chain changes the logging implementation to use string_stream
> so that the log will grow dynamically.
>
> The first 8 patches add test code for string_stream, and make some
> changes to string_stream needed to be able to use it for the log.
>
> The final patch adds a performance report of string_stream.
>
> CHANGES SINCE V3:
>
> Completely rewritten to use string_stream instead of implementing a
> separate extending-buffer implementation for logging.
>
> I have used the performance test from the final patch on my original
> fixed-size-fragment implementation from V3 to get a comparison of the
> two implementations (run on i3-8145UE CPU @ 2.20GHz):
>
>                         string_stream     V3 fixed-size-buffer
> Time elapsed:           7748 us           3251 us
> Total string length:    573890            573890
> Bytes requested:        823994            728336
> Actual bytes allocated: 1061440           728352
>
> I don't think the difference is enough to be worth complicating the
> string_stream implementation with my fixed-fragment implementation from
> V3 of this patch chain.

Hello!

I just wanted to note that I have tested this series and it looks good
to me. I specifically looked over the newline handling and that looks
really good.

I understand you will likely be doing a new version of this. But other
than the things noted in comments by David, this seems to be working
really well.

Tested-by: Rae Moar <rmoar@google.com>

Thanks for all the work you did in moving this framework to string-stream!
-Rae

>
> Richard Fitzgerald (10):
>   kunit: string-stream: Improve testing of string_stream
>   kunit: string-stream: Don't create a fragment for empty strings
>   kunit: string-stream: Add cases for adding empty strings to a
>     string_stream
>   kunit: string-stream: Add option to make all lines end with newline
>   kunit: string-stream: Add cases for string_stream newline appending
>   kunit: string-stream: Pass struct kunit to string_stream_get_string()
>   kunit: string-stream: Decouple string_stream from kunit
>   kunit: string-stream: Add test for freeing resource-managed
>     string_stream
>   kunit: Use string_stream for test log
>   kunit: string-stream: Test performance of string_stream
>
>  include/kunit/test.h           |  14 +-
>  lib/kunit/Makefile             |   5 +-
>  lib/kunit/debugfs.c            |  36 ++-
>  lib/kunit/kunit-test.c         |  52 +---
>  lib/kunit/log-test.c           |  72 ++++++
>  lib/kunit/string-stream-test.c | 447 +++++++++++++++++++++++++++++++--
>  lib/kunit/string-stream.c      | 129 +++++++---
>  lib/kunit/string-stream.h      |  22 +-
>  lib/kunit/test.c               |  48 +---
>  9 files changed, 656 insertions(+), 169 deletions(-)
>  create mode 100644 lib/kunit/log-test.c
>
> --
> 2.30.2
>