dma-debug: Make leak-like behaviour apparent
authorRobin Murphy <robin.murphy@arm.com>
Mon, 10 Dec 2018 14:00:30 +0000 (14:00 +0000)
committerChristoph Hellwig <hch@lst.de>
Tue, 11 Dec 2018 13:31:18 +0000 (14:31 +0100)
commitceb51173b2b5bd7af0d99079f6bbacdcfc58fe08
treebc9245f7e98c8e07a1d203d143da808330c244fd
parent2b9d9ac02b9d8d32c515c82bb17401c429f160ab
dma-debug: Make leak-like behaviour apparent

Now that we can dynamically allocate DMA debug entries to cope with
drivers maintaining excessively large numbers of live mappings, a driver
which *does* actually have a bug leaking mappings (and is not unloaded)
will no longer trigger the "DMA-API: debugging out of memory - disabling"
message until it gets to actual kernel OOM conditions, which means it
could go unnoticed for a while. To that end, let's inform the user each
time the pool has grown to a multiple of its initial size, which should
make it apparent that they either have a leak or might want to increase
the preallocation size.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Documentation/DMA-API.txt
kernel/dma/debug.c