[PATCH v2] dma-debug: Make things less spammy under memory pressure

[Rob Clark]

From: Rob Clark <robdclark at chromium.org>

Limit the error msg to avoid flooding the console.  If you have a lot of
threads hitting this at once, they could have already gotten passed the
dma_debug_disabled() check before they get to the point of allocation
failure, resulting in quite a lot of this error message spamming the
log.  Use pr_err_once() to limit that.

Signed-off-by: Rob Clark <robdclark at chromium.org>
---
v2: Use pr_err_once() instead of ratelimited, and spiff out commit msg a bit.

 kernel/dma/debug.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index f8ff598596b8..754e3456f017 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -564,7 +564,7 @@ static void add_dma_entry(struct dma_debug_entry *entry, unsigned long attrs)
 
 	rc = active_cacheline_insert(entry);
 	if (rc == -ENOMEM) {
-		pr_err("cacheline tracking ENOMEM, dma-debug disabled\n");
+		pr_err_once("cacheline tracking ENOMEM, dma-debug disabled\n");
 		global_disable = true;
 	} else if (rc == -EEXIST && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {
 		err_printk(entry->dev, entry,
-- 
2.36.1