The compiler is not automatically caching the i915->regs address inside
a register and emitting a load for every mmio access. For simple
functions like gen8_gt_irq_handler that are already using the raw
accessors, we can open-code them for substantial savings:
add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-83 (-83)
Function old new delta
gen8_gt_irq_handler 290 266 -24
gen8_gt_irq_ack 181 122 -59
Total: Before=954637, After=954554, chg -0.01%
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
---
And so begins the long haul of de-I915_READ/WRITE-ing the driver...
---
drivers/gpu/drm/i915/i915_irq.c | 57 +++++++++++++++++++----------------------
1 file changed, 27 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index b7b377ba7b6e..10d62b33cb13 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1413,9 +1413,11 @@ gen8_cs_irq_handler(struct intel_engine_cs *engine, u32 iir, int test_shift)
tasklet_hi_schedule(&execlists->tasklet);
}
-static void gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
+static void gen8_gt_irq_ack(struct drm_i915_private *i915,
u32 master_ctl, u32 gt_iir[4])
{
+ void __iomem * const regs = i915->regs;
+
#define GEN8_GT_IRQS (GEN8_GT_RCS_IRQ | \
GEN8_GT_BCS_IRQ | \
GEN8_GT_VCS1_IRQ | \
@@ -1425,62 +1427,57 @@ static void gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
GEN8_GT_GUC_IRQ)
if (master_ctl & (GEN8_GT_RCS_IRQ | GEN8_GT_BCS_IRQ)) {
- gt_iir[0] = I915_READ_FW(GEN8_GT_IIR(0));
- if (gt_iir[0])
- I915_WRITE_FW(GEN8_GT_IIR(0), gt_iir[0]);
+ gt_iir[0] = readl(regs + i915_mmio_reg_offset(GEN8_GT_IIR(0)));
+ if (likely(gt_iir[0]))
+ writel(gt_iir[0], regs + i915_mmio_reg_offset(GEN8_GT_IIR(0)));
}
if (master_ctl & (GEN8_GT_VCS1_IRQ | GEN8_GT_VCS2_IRQ)) {
- gt_iir[1] = I915_READ_FW(GEN8_GT_IIR(1));
- if (gt_iir[1])
- I915_WRITE_FW(GEN8_GT_IIR(1), gt_iir[1]);
+ gt_iir[1] = readl(regs + i915_mmio_reg_offset(GEN8_GT_IIR(1)));
+ if (likely(gt_iir[1]))
+ writel(gt_iir[1], regs + i915_mmio_reg_offset(GEN8_GT_IIR(1)));
}
- if (master_ctl & GEN8_GT_VECS_IRQ) {
- gt_iir[3] = I915_READ_FW(GEN8_GT_IIR(3));
- if (gt_iir[3])
- I915_WRITE_FW(GEN8_GT_IIR(3), gt_iir[3]);
+ if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
+ gt_iir[2] = readl(regs + i915_mmio_reg_offset(GEN8_GT_IIR(2)));
+ if (likely(gt_iir[2] & (i915->pm_rps_events | i915->pm_guc_events)))
+ writel(gt_iir[2] & (i915->pm_rps_events |
+ i915->pm_guc_events),
+ regs + i915_mmio_reg_offset(GEN8_GT_IIR(2)));
}
- if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
- gt_iir[2] = I915_READ_FW(GEN8_GT_IIR(2));
- if (gt_iir[2] & (dev_priv->pm_rps_events |
- dev_priv->pm_guc_events)) {
- I915_WRITE_FW(GEN8_GT_IIR(2),
- gt_iir[2] & (dev_priv->pm_rps_events |
- dev_priv->pm_guc_events));
- }
+ if (master_ctl & GEN8_GT_VECS_IRQ) {
+ gt_iir[3] = readl(regs + i915_mmio_reg_offset(GEN8_GT_IIR(3)));
+ if (likely(gt_iir[3]))
+ writel(gt_iir[3], regs + i915_mmio_reg_offset(GEN8_GT_IIR(3)));
}
}
-static void gen8_gt_irq_handler(struct drm_i915_private *dev_priv,
+static void gen8_gt_irq_handler(struct drm_i915_private *i915,
u32 master_ctl, u32 gt_iir[4])
{
if (master_ctl & (GEN8_GT_RCS_IRQ | GEN8_GT_BCS_IRQ)) {
- gen8_cs_irq_handler(dev_priv->engine[RCS],
+ gen8_cs_irq_handler(i915->engine[RCS],
gt_iir[0], GEN8_RCS_IRQ_SHIFT);
- gen8_cs_irq_handler(dev_priv->engine[BCS],
+ gen8_cs_irq_handler(i915->engine[BCS],
gt_iir[0], GEN8_BCS_IRQ_SHIFT);
}
if (master_ctl & (GEN8_GT_VCS1_IRQ | GEN8_GT_VCS2_IRQ)) {
- gen8_cs_irq_handler(dev_priv->engine[VCS],
+ gen8_cs_irq_handler(i915->engine[VCS],
gt_iir[1], GEN8_VCS1_IRQ_SHIFT);
- gen8_cs_irq_handler(dev_priv->engine[VCS2],
+ gen8_cs_irq_handler(i915->engine[VCS2],
gt_iir[1], GEN8_VCS2_IRQ_SHIFT);
}
if (master_ctl & GEN8_GT_VECS_IRQ) {
- gen8_cs_irq_handler(dev_priv->engine[VECS],
+ gen8_cs_irq_handler(i915->engine[VECS],
gt_iir[3], GEN8_VECS_IRQ_SHIFT);
}
if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
- if (gt_iir[2] & dev_priv->pm_rps_events)
- gen6_rps_irq_handler(dev_priv, gt_iir[2]);
-
- if (gt_iir[2] & dev_priv->pm_guc_events)
- gen9_guc_irq_handler(dev_priv, gt_iir[2]);
+ gen6_rps_irq_handler(i915, gt_iir[2]);
+ gen9_guc_irq_handler(i915, gt_iir[2]);
}
}
--
2.16.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
