On Thu, Dec 10, 2020 at 12:26:01PM +0100, Daniel Vetter wrote: > On Thu, Dec 10, 2020 at 11:55 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Thu, Dec 10, 2020 at 11:27:27AM +0100, Daniel Vetter wrote: > > > On Thu, Dec 10, 2020 at 11:10:45AM +0100, Greg KH wrote: > > > > On Thu, Dec 10, 2020 at 10:58:50AM +0100, Christian König wrote: > > > > > In general a good idea, but I have a few concern/comments here. > > > > > > > > > > Am 10.12.20 um 05:43 schrieb Hridya Valsaraju: > > > > > > This patch allows statistics to be enabled for each DMA-BUF in > > > > > > sysfs by enabling the config CONFIG_DMABUF_SYSFS_STATS. > > > > > > > > > > > > The following stats will be exposed by the interface: > > > > > > > > > > > > /sys/kernel/dmabuf/<inode_number>/exporter_name > > > > > > /sys/kernel/dmabuf/<inode_number>/size > > > > > > /sys/kernel/dmabuf/<inode_number>/dev_map_info > > > > > > > > > > > > The inode_number is unique for each DMA-BUF and was added earlier [1] > > > > > > in order to allow userspace to track DMA-BUF usage across different > > > > > > processes. > > > > > > > > > > > > Currently, this information is exposed in > > > > > > /sys/kernel/debug/dma_buf/bufinfo. > > > > > > However, since debugfs is considered unsafe to be mounted in production, > > > > > > it is being duplicated in sysfs. > > > > > > > > > > Mhm, this makes it part of the UAPI. What is the justification for this? > > > > > > > > > > In other words do we really need those debug information in a production > > > > > environment? > > > > > > > > Production environments seem to want to know who is using up memory :) > > > > > > This only shows shared memory, so it does smell a lot like $specific_issue > > > and we're designing a narrow solution for that and then have to carry it > > > forever. > > > > I think the "issue" is that this was a feature from ion that people > > "missed" in the dmabuf move. Taking away the ability to see what kind > > of allocations were being made didn't make a lot of debugging tools > > happy :( > > If this is just for dma-heaps then why don't we add the stuff back > over there? It reinforces more that the android gpu stack and the > non-android gpu stack on linux are fairly different in fundamental > ways, but that's not really new. Back "over where"? dma-bufs are not only used for the graphics stack on android from what I can tell, so this shouldn't be a gpu-specific issue. confused, greg k-h _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
