From: Eric Dumazet edumazet@google.com
[ Upstream commit 9ff6aa027dbb98755f0265695354f2dd07c0d1ce ]
debug_dma_dump_mappings() can take a lot of cpu cycles :
lpk43:/# time wc -l /sys/kernel/debug/dma-api/dump 163435 /sys/kernel/debug/dma-api/dump
real 0m0.463s user 0m0.003s sys 0m0.459s
Let's add a cond_resched() to avoid holding cpu for too long.
Signed-off-by: Eric Dumazet edumazet@google.com Cc: Corentin Labbe clabbe@baylibre.com Cc: Christoph Hellwig hch@lst.de Cc: Marek Szyprowski m.szyprowski@samsung.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- lib/dma-debug.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/lib/dma-debug.c b/lib/dma-debug.c index 51a76af25c66..173013f5e41b 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -427,6 +427,7 @@ void debug_dma_dump_mappings(struct device *dev) }
spin_unlock_irqrestore(&bucket->lock, flags); + cond_resched(); } } EXPORT_SYMBOL(debug_dma_dump_mappings);