drm/mediatek: Use spin_lock_irqsave() for CRTC event lock

[PATCH] drm/mediatek: Use spin_lock_irqsave() for CRTC event lock

Posted by Fei Shao 3 weeks, 1 day ago

Use the state-aware spin_lock_irqsave() and spin_unlock_irqrestore()
to avoid unconditionally re-enabling the local interrupts.

Fixes: 411f5c1eacfe ("drm/mediatek: handle events when enabling/disabling crtc")
Signed-off-by: Fei Shao <fshao@chromium.org>
---

 drivers/gpu/drm/mediatek/mtk_crtc.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
index 6f34f573e127..42f47086f414 100644
--- a/drivers/gpu/drm/mediatek/mtk_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
@@ -449,6 +449,7 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_crtc *mtk_crtc)
 {
 	struct drm_device *drm = mtk_crtc->base.dev;
 	struct drm_crtc *crtc = &mtk_crtc->base;
+	unsigned long flags;
 	int i;
 
 	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
@@ -480,10 +481,10 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_crtc *mtk_crtc)
 	pm_runtime_put(drm->dev);
 
 	if (crtc->state->event && !crtc->state->active) {
-		spin_lock_irq(&crtc->dev->event_lock);
+		spin_lock_irqsave(&crtc->dev->event_lock, flags);
 		drm_crtc_send_vblank_event(crtc, crtc->state->event);
 		crtc->state->event = NULL;
-		spin_unlock_irq(&crtc->dev->event_lock);
+		spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
 	}
 }
 
-- 
2.46.0.295.g3b9ea8a38a-goog

Re: [PATCH] drm/mediatek: Use spin_lock_irqsave() for CRTC event lock

Posted by Chun-Kuang Hu 2 weeks, 6 days ago

Hi, Fei:

Fei Shao <fshao@chromium.org> 於 2024年8月28日 週三 下午6:16寫道：
>
> Use the state-aware spin_lock_irqsave() and spin_unlock_irqrestore()
> to avoid unconditionally re-enabling the local interrupts.

Applied to mediatek-drm-next [1], thanks.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next

Regards,
Chun-Kuang.

>
> Fixes: 411f5c1eacfe ("drm/mediatek: handle events when enabling/disabling crtc")
> Signed-off-by: Fei Shao <fshao@chromium.org>
> ---
>
>  drivers/gpu/drm/mediatek/mtk_crtc.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
> index 6f34f573e127..42f47086f414 100644
> --- a/drivers/gpu/drm/mediatek/mtk_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
> @@ -449,6 +449,7 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_crtc *mtk_crtc)
>  {
>         struct drm_device *drm = mtk_crtc->base.dev;
>         struct drm_crtc *crtc = &mtk_crtc->base;
> +       unsigned long flags;
>         int i;
>
>         for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
> @@ -480,10 +481,10 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_crtc *mtk_crtc)
>         pm_runtime_put(drm->dev);
>
>         if (crtc->state->event && !crtc->state->active) {
> -               spin_lock_irq(&crtc->dev->event_lock);
> +               spin_lock_irqsave(&crtc->dev->event_lock, flags);
>                 drm_crtc_send_vblank_event(crtc, crtc->state->event);
>                 crtc->state->event = NULL;
> -               spin_unlock_irq(&crtc->dev->event_lock);
> +               spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
>         }
>  }
>
> --
> 2.46.0.295.g3b9ea8a38a-goog
>