Re: [PATCH 4/4] mtd: rawnand: meson: only initialize the RB completion once

From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
To: Liang Yang <liang.yang@amlogic.com>
Cc: linux-amlogic@lists.infradead.org, linux-mtd@lists.infradead.org,
	richard@nod.at, miquel.raynal@bootlin.com,
	linux-arm-kernel@lists.infradead.org, marek.vasut@gmail.com,
	linux-kernel@vger.kernel.org, computersforpeace@gmail.com,
	dwmw2@infradead.org, bbrezillon@kernel.org,
	jianxin.pan@amlogic.com
Subject: Re: [PATCH 4/4] mtd: rawnand: meson: only initialize the RB completion once
Date: Thu, 18 Apr 2019 21:44:05 +0200	[thread overview]
Message-ID: <CAFBinCB9Z_H4wX3_g2hVL-XnS6Oq-KtPHa4Z1ws79FGp5jCapQ@mail.gmail.com> (raw)
In-Reply-To: <bd1900db-7ca1-a6e5-39f9-db54e0b570dd@amlogic.com>

Hi Liang,

On Mon, Apr 15, 2019 at 8:04 AM Liang Yang <liang.yang@amlogic.com> wrote:
>
>
> On 2019/4/12 6:00, Martin Blumenstingl wrote:
> > Documentation/scheduler/completion.txt states:
> >    Calling init_completion() on the same completion object twice is
> >    most likely a bug as it re-initializes the queue to an empty queue and
> >    enqueued tasks could get "lost" - use reinit_completion() in that case,
> >    but be aware of other races.
> >
> > Initialize nfc->completion in meson_nfc_probe using init_completion and
> > change the call in meson_nfc_queue_rb to reinit_completion so the logic
> > matches what the documentation suggests.
> >
> > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> > ---
> >   drivers/mtd/nand/raw/meson_nand.c | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c
> > index 57cc4bd3f665..ea57ddcec41e 100644
> > --- a/drivers/mtd/nand/raw/meson_nand.c
> > +++ b/drivers/mtd/nand/raw/meson_nand.c
> > @@ -400,7 +400,7 @@ static int meson_nfc_queue_rb(struct meson_nfc *nfc, int timeout_ms)
> >       cfg |= NFC_RB_IRQ_EN;
> >       writel(cfg, nfc->reg_base + NFC_REG_CFG);
> >
> > -     init_completion(&nfc->completion);
> > +     reinit_completion(&nfc->completion);
> Tested-by:Liang Yang <liang.yang@amlogic.com>
> Acked-by: Liang Yang <liang.yang@amlogic.com>
thank you for reviewing and testing my patches!

[...]
> Tested-by:Liang Yang <liang.yang@amlogic.com>
> Acked-by: Liang Yang <liang.yang@amlogic.com>
please consider the following note for future code-reviews:
most maintainers take the patch from patchwork and apply it to their git tree.
however, patchwork is not smart enough to detect when the same
Tested-by/Acked-by is sent multiple times.
this results in the same Tested-by/Acked-by being listed multiple
times in the final commit: [0]

what I do instead is to reply with one set of Tested-by/Acked-by
(below the author's Signed-off-by) which is then valid for the whole
patch.
There's no problem to have Tested-by and Acked-by at the same time,
the issue only shows up if you send Acked-by (or any other tag) for
the same patch multiple times.

Have a great day!
Regards,
Martin

[0] https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git/commit/?h=nand/next&id=39e01956e2f70ff9f0e97db1a69c9847aa1d5d8b