public inbox for linux-media@vger.kernel.org
 help / color / mirror / Atom feed
From: Dan Scally <dan.scally@ideasonboard.com>
To: Jacopo Mondi <jacopo.mondi@ideasonboard.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
	Biju Das <biju.das.jz@bp.renesas.com>,
	Hans Verkuil <hverkuil+cisco@kernel.org>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Cc: "Barnabás Pőcze" <pobrn@protonmail.com>,
	"Lad Prabhakar" <prabhakar.mahadev-lad.rj@bp.renesas.com>,
	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 14/15] media: rzg2l-cru: Remove debug printouts from irq
Date: Tue, 31 Mar 2026 11:45:45 +0100	[thread overview]
Message-ID: <4bd1ecdc-294b-4261-ae1f-1e8f1384bcd0@ideasonboard.com> (raw)
In-Reply-To: <20260331-b4-cru-rework-v2-14-f94b238b35d4@ideasonboard.com>

Hi Jacopo

On 31/03/2026 11:27, Jacopo Mondi wrote:
> Using dev_dbg() in irq handlers to debug per-frame events is marginally
> useful and possibly not the best idea, as using printk-based helpers
> introduce latencies that impact the drivers operations.
> 
> If any tracing/debugging has to be performed around frame events
> in interrupt handlers, the tracing subsystem offers better alternatives.
> 
> Drop dev_dgb() calls from the CRU interrupt handlers.
> 
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>

Yeah good idea:

Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>

> ---
>   drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c | 8 --------
>   1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> index 721057edca6b..e2073cc1afc6 100644
> --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> @@ -627,9 +627,6 @@ irqreturn_t rzg2l_cru_irq(int irq, void *data)
>   		vb2_buffer_done(&cru->queue_buf[slot]->vb2_buf,
>   				VB2_BUF_STATE_DONE);
>   		cru->queue_buf[slot] = NULL;
> -	} else {
> -		/* Scratch buffer was used, dropping frame. */
> -		dev_dbg(cru->dev, "Dropping frame %u\n", cru->sequence);
>   	}
>   
>   	cru->sequence++;
> @@ -656,8 +653,6 @@ irqreturn_t rzg3e_cru_irq(int irq, void *data)
>   	slot = cru->active_slot;
>   	cru->active_slot = rzg2l_cru_slot_next(cru, cru->active_slot);
>   
> -	dev_dbg(cru->dev, "Current written slot: %d\n", slot);
> -
>   	/* Capture frame */
>   	if (cru->queue_buf[slot]) {
>   		struct vb2_v4l2_buffer *buf = cru->queue_buf[slot];
> @@ -667,9 +662,6 @@ irqreturn_t rzg3e_cru_irq(int irq, void *data)
>   		buf->vb2_buf.timestamp = ktime_get_ns();
>   		vb2_buffer_done(&buf->vb2_buf, VB2_BUF_STATE_DONE);
>   		cru->queue_buf[slot] = NULL;
> -	} else {
> -		/* Scratch buffer was used, dropping frame. */
> -		dev_dbg(cru->dev, "Dropping frame %u\n", cru->sequence);
>   	}
>   
>   	cru->sequence++;
> 


  reply	other threads:[~2026-03-31 10:45 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-31 10:27 [PATCH v2 00/15] media: rzg2l-cru: Rework slot programming for V2H/G3E Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 01/15] media: rzg2l-cru: Skip ICnMC configuration when ICnSVC is used Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 02/15] media: rzg2l-cru: Use only frame end interrupts Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 03/15] media: rzg2l-cru: Modernize locking usage with guards Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 04/15] media: rzg2l-cru: Use proper guard() in irq handler Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 05/15] media: rzg2l-cru: Remove locking from start/stop routines Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 06/15] media: rzg2l-cru: Do not use irqsave when not needed Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 07/15] media: rzg2l-cru: Remove wrong locking comment Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 08/15] media: rz2gl-cru: Introduce a spinlock for hw operations Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 09/15] media: rzg2l-cru: Split hw locking from buffers Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 10/15] media: rzg2l-cru: Manually track active slot number Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 11/15] media: rz2gl-cru: Return pending buffers in order Jacopo Mondi
2026-03-31 10:27 ` [PATCH v2 12/15] media: rzg2l-cru: Rework rzg2l_cru_fill_hw_slot() Jacopo Mondi
2026-03-31 16:26   ` Tommaso Merciai
2026-03-31 10:27 ` [PATCH v2 13/15] media: rzg2l-cru: Remove the 'state' variable Jacopo Mondi
2026-03-31 16:32   ` Tommaso Merciai
2026-03-31 10:27 ` [PATCH v2 14/15] media: rzg2l-cru: Remove debug printouts from irq Jacopo Mondi
2026-03-31 10:45   ` Dan Scally [this message]
2026-03-31 10:27 ` [PATCH v2 15/15] media: rzg2l-cru: Simplify irq return value handling Jacopo Mondi

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=4bd1ecdc-294b-4261-ae1f-1e8f1384bcd0@ideasonboard.com \
    --to=dan.scally@ideasonboard.com \
    --cc=biju.das.jz@bp.renesas.com \
    --cc=hverkuil+cisco@kernel.org \
    --cc=jacopo.mondi@ideasonboard.com \
    --cc=laurent.pinchart+renesas@ideasonboard.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@kernel.org \
    --cc=pobrn@protonmail.com \
    --cc=prabhakar.mahadev-lad.rj@bp.renesas.com \
    --cc=sakari.ailus@linux.intel.com \
    --cc=tommaso.merciai.xr@bp.renesas.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