On Tue, Jan 19, 2021 at 12:36:40PM -0800, Minchan Kim wrote: > On Tue, Jan 19, 2021 at 10:29:29AM -0800, John Stultz wrote: > > On Tue, Jan 12, 2021 at 5:22 PM Minchan Kim <minchan@xxxxxxxxxx> wrote: > > > > > > From: Hyesoo Yu <hyesoo.yu@xxxxxxxxxxx> > > > > > > This patch supports chunk heap that allocates the buffers that > > > arranged into a list a fixed size chunks taken from CMA. > > > > > > The chunk heap driver is bound directly to a reserved_memory > > > node by following Rob Herring's suggestion in [1]. > > > > > > [1] https://lore.kernel.org/lkml/20191025225009.50305-2-john.stultz@xxxxxxxxxx/T/#m3dc63acd33fea269a584f43bb799a876f0b2b45d > > > > > > Signed-off-by: Hyesoo Yu <hyesoo.yu@xxxxxxxxxxx> > > > Signed-off-by: Hridya Valsaraju <hridya@xxxxxxxxxx> > > > Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> > > > --- > > ... > > > +static int register_chunk_heap(struct chunk_heap *chunk_heap_info) > > > +{ > > > + struct dma_heap_export_info exp_info; > > > + > > > + exp_info.name = cma_get_name(chunk_heap_info->cma); > > > > One potential issue here, you're setting the name to the same as the > > CMA name. Since the CMA heap uses the CMA name, if one chunk was > > registered as a chunk heap but also was the default CMA area, it might > > be registered twice. But since both would have the same name it would > > be an initialization race as to which one "wins". > > Good point. Maybe someone might want to use default CMA area for > both cma_heap and chunk_heap. I cannot come up with ideas why we > should prohibit it atm. > > > > > So maybe could you postfix the CMA name with "-chunk" or something? > > Hyesoo, Any opinion? > Unless you have something other idea, let's fix it in next version. > I agree that. It is not good to use heap name directly as cma name. Let's postfix the name with '-chunk' Thanks, Regards.