diff options
| author | Lyude Paul <lyude@redhat.com> | 2020-06-23 23:24:00 +0300 |
|---|---|---|
| committer | Lyude Paul <lyude@redhat.com> | 2020-07-17 01:16:31 +0300 |
| commit | a7e3ad5fdc51b4795cb935282819996718c0d187 (patch) | |
| tree | a8f465b5111f6e836fe7fbd6ce2647f736eb5f46 /drivers/gpu/drm/drm_vblank.c | |
| parent | a7e5e06de22223e0a00f569ea8446243d5f58386 (diff) | |
| download | linux-a7e3ad5fdc51b4795cb935282819996718c0d187.tar.xz | |
drm/vblank: Use spin_(un)lock_irq() in drm_crtc_vblank_off()
This got me confused for a bit while looking over this code: I had been
planning on adding some blocking function calls into this function, but
seeing the irqsave/irqrestore variants of spin_(un)lock() didn't make it
very clear whether or not that would actually be safe.
So I went ahead and reviewed every single driver in the kernel that uses
this function, and they all fall into three categories:
* Driver probe code
* ->atomic_disable() callbacks
* Legacy modesetting callbacks
All of these will be guaranteed to have IRQs enabled, which means it's
perfectly safe to block here. Just to make things a little less
confusing to others in the future, let's switch over to
spin_lock_irq()/spin_unlock_irq() to make that fact a little more
obvious.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200627194657.156514-3-lyude@redhat.com
Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
| -rw-r--r-- | drivers/gpu/drm/drm_vblank.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 4b0a9b206116..e277e40e5b82 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -1283,13 +1283,12 @@ void drm_crtc_vblank_off(struct drm_crtc *crtc) struct drm_pending_vblank_event *e, *t; ktime_t now; - unsigned long irqflags; u64 seq; if (drm_WARN_ON(dev, pipe >= dev->num_crtcs)) return; - spin_lock_irqsave(&dev->event_lock, irqflags); + spin_lock_irq(&dev->event_lock); spin_lock(&dev->vbl_lock); drm_dbg_vbl(dev, "crtc %d, vblank enabled %d, inmodeset %d\n", @@ -1325,7 +1324,7 @@ void drm_crtc_vblank_off(struct drm_crtc *crtc) drm_vblank_put(dev, pipe); send_vblank_event(dev, e, seq, now); } - spin_unlock_irqrestore(&dev->event_lock, irqflags); + spin_unlock_irq(&dev->event_lock); /* Will be reset by the modeset helpers when re-enabling the crtc by * calling drm_calc_timestamping_constants(). */ |