dma-buf: deprecate DMABUF_SYSFS_STATS

Add a warning that this UAPI wasn't such a good idea and shouldn't be
used by anybody.

That should give us a better chance to remove it at some point and
prevents others from running into the same issues.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: T.J. Mercier <tjmercier@google.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220617085702.4298-1-christian.koenig@amd.com

diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig
index 541efe01abc7c4323d9ac20283681c282556f432..e4dc53a364282457e6a85fbc9a09f27ad561c401 100644 (file)
--- a/drivers/dma-buf/Kconfig
+++ b/drivers/dma-buf/Kconfig
@@ -75,7 +75,7 @@ menuconfig DMABUF_HEAPS
          between drivers.
 
 menuconfig DMABUF_SYSFS_STATS
-       bool "DMA-BUF sysfs statistics"
+       bool "DMA-BUF sysfs statistics (DEPRECATED)"
        depends on DMA_SHARED_BUFFER
        help
           Choose this option to enable DMA-BUF sysfs statistics
@@ -85,6 +85,10 @@ menuconfig DMABUF_SYSFS_STATS
           statistics for the DMA-BUF with the unique inode number
           <inode_number>.
 
+          This option is deprecated and should sooner or later be removed.
+          Android is the only user of this and it turned out that this resulted
+          in quite some performance problems.
+
 source "drivers/dma-buf/heaps/Kconfig"
 
 endmenu