From b2c88f5b1dea77b57759387728917a124eb1c098 Mon Sep 17 00:00:00 2001 From: Damien Lespiau Date: Tue, 15 Oct 2013 18:55:29 +0100 Subject: [PATCH] drm/i915: Keep the CRC values into a circular buffer There are a few good properties to a circular buffer, for instance it has a number of entries (before we were always dumping the full buffer). Signed-off-by: Damien Lespiau Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_debugfs.c | 20 ++++++++++++-------- drivers/gpu/drm/i915/i915_drv.h | 4 ++-- drivers/gpu/drm/i915/i915_irq.c | 19 +++++++++++++++---- 3 files changed, 29 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 0d8a9a397a24..991abff94e1e 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -27,6 +27,7 @@ */ #include +#include #include #include #include @@ -1739,25 +1740,28 @@ static int i915_pipe_crc(struct seq_file *m, void *data) struct drm_device *dev = node->minor->dev; struct drm_i915_private *dev_priv = dev->dev_private; enum pipe pipe = (enum pipe)node->info_ent->data; - const struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; - int i; - int start; + struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; + int head, tail; if (dev_priv->pipe_crc[pipe].source == INTEL_PIPE_CRC_SOURCE_NONE) { seq_puts(m, "none\n"); return 0; } - start = atomic_read(&pipe_crc->slot) + 1; seq_puts(m, " timestamp CRC1 CRC2 CRC3 CRC4 CRC5\n"); - for (i = 0; i < INTEL_PIPE_CRC_ENTRIES_NR; i++) { - const struct intel_pipe_crc_entry *entry = - &pipe_crc->entries[(start + i) % - INTEL_PIPE_CRC_ENTRIES_NR]; + head = atomic_read(&pipe_crc->head); + tail = atomic_read(&pipe_crc->tail); + + while (CIRC_CNT(head, tail, INTEL_PIPE_CRC_ENTRIES_NR) >= 1) { + struct intel_pipe_crc_entry *entry = &pipe_crc->entries[tail]; seq_printf(m, "%12u %8x %8x %8x %8x %8x\n", entry->timestamp, entry->crc[0], entry->crc[1], entry->crc[2], entry->crc[3], entry->crc[4]); + + BUILD_BUG_ON_NOT_POWER_OF_2(INTEL_PIPE_CRC_ENTRIES_NR); + tail = (tail + 1) & (INTEL_PIPE_CRC_ENTRIES_NR - 1); + atomic_set(&pipe_crc->tail, tail); } return 0; diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index bfaaaaee8a5b..a29a4a1d300a 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1230,11 +1230,11 @@ struct intel_pipe_crc_entry { uint32_t crc[5]; }; -#define INTEL_PIPE_CRC_ENTRIES_NR 200 +#define INTEL_PIPE_CRC_ENTRIES_NR 128 struct intel_pipe_crc { struct intel_pipe_crc_entry entries[INTEL_PIPE_CRC_ENTRIES_NR]; enum intel_pipe_crc_source source; - atomic_t slot; + atomic_t head, tail; }; typedef struct drm_i915_private { diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index d2074f129a36..73d76af13ed4 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -30,6 +30,7 @@ #include #include +#include #include #include #include "i915_drv.h" @@ -1195,20 +1196,30 @@ static void ivb_pipe_crc_update(struct drm_device *dev, enum pipe pipe) struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe]; struct intel_pipe_crc_entry *entry; ktime_t now; - int ts, slot; + int ts, head, tail; + + head = atomic_read(&pipe_crc->head); + tail = atomic_read(&pipe_crc->tail); + + if (CIRC_SPACE(head, tail, INTEL_PIPE_CRC_ENTRIES_NR) < 1) { + DRM_ERROR("CRC buffer overflowing\n"); + return; + } + + entry = &pipe_crc->entries[head]; now = ktime_get(); ts = ktime_to_us(now); - slot = (atomic_read(&pipe_crc->slot) + 1) % INTEL_PIPE_CRC_ENTRIES_NR; - entry = &pipe_crc->entries[slot]; entry->timestamp = ts; entry->crc[0] = I915_READ(PIPE_CRC_RES_1_IVB(pipe)); entry->crc[1] = I915_READ(PIPE_CRC_RES_2_IVB(pipe)); entry->crc[2] = I915_READ(PIPE_CRC_RES_3_IVB(pipe)); entry->crc[3] = I915_READ(PIPE_CRC_RES_4_IVB(pipe)); entry->crc[4] = I915_READ(PIPE_CRC_RES_5_IVB(pipe)); - atomic_set(&dev_priv->pipe_crc[pipe].slot, slot); + + head = (head + 1) & (INTEL_PIPE_CRC_ENTRIES_NR - 1); + atomic_set(&pipe_crc->head, head); } #else static void ivb_pipe_crc_update(struct drm_device *dev, int pipe) {} -- 2.34.1