From: Ville Syrjala <ville.syrjala@linux.intel.com>
To: dri-devel@lists.freedesktop.org
Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org
Subject: [PATCH] drm/vblank: Extract get_vblank_counter_and_timestamp()
Date: Mon, 23 Mar 2026 23:36:45 +0200 [thread overview]
Message-ID: <20260323213645.10965-1-ville.syrjala@linux.intel.com> (raw)
From: Ville Syrjälä <ville.syrjala@linux.intel.com>
We have three copies of the "read vblank counter and timestamp
in a loop" code. Consolidate to a single a function.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/drm_vblank.c | 36 +++++++++++++++++++++---------------
1 file changed, 21 insertions(+), 15 deletions(-)
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index f78bf37f1e0a..f90fb2d13e42 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -236,6 +236,21 @@ static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe)
return drm_vblank_no_hw_counter(dev, pipe);
}
+static bool get_vblank_counter_and_timestamp(struct drm_device *dev, unsigned int pipe,
+ u32 *cur_vblank, ktime_t *t_vblank,
+ bool in_vblank_irq)
+{
+ int count = DRM_TIMESTAMP_MAXRETRIES;
+ bool rc;
+
+ do {
+ *cur_vblank = __get_vblank_counter(dev, pipe);
+ rc = drm_get_last_vbltimestamp(dev, pipe, t_vblank, in_vblank_irq);
+ } while (*cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+
+ return rc;
+}
+
/*
* Reset the stored timestamp for the current vblank count to correspond
* to the last vblank occurred.
@@ -250,7 +265,6 @@ static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe
u32 cur_vblank;
bool rc;
ktime_t t_vblank;
- int count = DRM_TIMESTAMP_MAXRETRIES;
spin_lock(&dev->vblank_time_lock);
@@ -258,10 +272,8 @@ static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe
* sample the current counter to avoid random jumps
* when drm_vblank_enable() applies the diff
*/
- do {
- cur_vblank = __get_vblank_counter(dev, pipe);
- rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
- } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+ rc = get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+ &t_vblank, false);
/*
* Only reinitialize corresponding vblank timestamp if high-precision query
@@ -299,7 +311,6 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
u32 cur_vblank, diff;
bool rc;
ktime_t t_vblank;
- int count = DRM_TIMESTAMP_MAXRETRIES;
int framedur_ns = vblank->framedur_ns;
u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
@@ -315,10 +326,8 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
* updating its hardware counter while we are retrieving the
* corresponding vblank timestamp.
*/
- do {
- cur_vblank = __get_vblank_counter(dev, pipe);
- rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq);
- } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+ rc = get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+ &t_vblank, in_vblank_irq);
if (max_vblank_count) {
/* trust the hw counter when it's around */
@@ -1543,7 +1552,6 @@ static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
int framedur_ns;
u64 diff_ns;
u32 cur_vblank, diff = 1;
- int count = DRM_TIMESTAMP_MAXRETRIES;
u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
@@ -1558,10 +1566,8 @@ static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
"Cannot compute missed vblanks without frame duration\n");
framedur_ns = vblank->framedur_ns;
- do {
- cur_vblank = __get_vblank_counter(dev, pipe);
- drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
- } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+ get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+ &t_vblank, false);
diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
if (framedur_ns)
--
2.52.0
next reply other threads:[~2026-03-23 21:36 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-23 21:36 Ville Syrjala [this message]
2026-03-24 6:28 ` [PATCH] drm/vblank: Extract get_vblank_counter_and_timestamp() Kandpal, Suraj
2026-03-24 21:15 ` Claude review: " Claude Code Review Bot
2026-03-24 21:15 ` Claude Code Review Bot
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