From a012024571d98e2e4bf29a9168fb7ddc44b7ab86 Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Wed, 18 Apr 2018 14:51:21 +0200 Subject: [PATCH] drm/crc: Only report a single overflow when a CRC fd is opened MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This reduces the amount of spam when you debug a CRC reading program. Signed-off-by: Maarten Lankhorst [mlankhorst: Change bool overflow to was_overflow (Ville)] Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20180418125121.72081-1-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/drm_debugfs_crc.c | 9 ++++++++- include/drm/drm_debugfs_crc.h | 3 ++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c index 9f8312137cad..99961192bf03 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -139,6 +139,7 @@ static int crtc_crc_data_count(struct drm_crtc_crc *crc) static void crtc_crc_cleanup(struct drm_crtc_crc *crc) { kfree(crc->entries); + crc->overflow = false; crc->entries = NULL; crc->head = 0; crc->tail = 0; @@ -391,8 +392,14 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame, tail = crc->tail; if (CIRC_SPACE(head, tail, DRM_CRC_ENTRIES_NR) < 1) { + bool was_overflow = crc->overflow; + + crc->overflow = true; spin_unlock(&crc->lock); - DRM_ERROR("Overflow of CRC buffer, userspace reads too slow.\n"); + + if (!was_overflow) + DRM_ERROR("Overflow of CRC buffer, userspace reads too slow.\n"); + return -ENOBUFS; } diff --git a/include/drm/drm_debugfs_crc.h b/include/drm/drm_debugfs_crc.h index 7d63b1d4adb9..b225eeb30d05 100644 --- a/include/drm/drm_debugfs_crc.h +++ b/include/drm/drm_debugfs_crc.h @@ -43,6 +43,7 @@ struct drm_crtc_crc_entry { * @lock: protects the fields in this struct * @source: name of the currently configured source of CRCs * @opened: whether userspace has opened the data file for reading + * @overflow: whether an overflow occured. * @entries: array of entries, with size of %DRM_CRC_ENTRIES_NR * @head: head of circular queue * @tail: tail of circular queue @@ -52,7 +53,7 @@ struct drm_crtc_crc_entry { struct drm_crtc_crc { spinlock_t lock; const char *source; - bool opened; + bool opened, overflow; struct drm_crtc_crc_entry *entries; int head, tail; size_t values_cnt; -- 2.30.2