On Thu, Dec 17, 2020 at 11:06:11PM +0000, John Stultz wrote: > Reuse/abuse the pagepool code from the network code to speed > up allocation performance. > > This is similar to the ION pagepool usage, but tries to > utilize generic code instead of a custom implementation. > > Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx> > Cc: Liam Mark <lmark@xxxxxxxxxxxxxx> > Cc: Chris Goldsworthy <cgoldswo@xxxxxxxxxxxxxx> > Cc: Laura Abbott <labbott@xxxxxxxxxx> > Cc: Brian Starkey <Brian.Starkey@xxxxxxx> > Cc: Hridya Valsaraju <hridya@xxxxxxxxxx> > Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx> > Cc: Sandeep Patil <sspatil@xxxxxxxxxx> > Cc: Daniel Mentz <danielmentz@xxxxxxxxxx> > Cc: Ørjan Eide <orjan.eide@xxxxxxx> > Cc: Robin Murphy <robin.murphy@xxxxxxx> > Cc: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx> > Cc: Simon Ser <contact@xxxxxxxxxxx> > Cc: James Jones <jajones@xxxxxxxxxx> > Cc: linux-media@xxxxxxxxxxxxxxx > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> We also have one of these in ttm. I think we should have at most one of these for the gpu ecosystem overall, maybe as a helper that can be plugged into all the places. Or I'm kinda missing something, which could be since I only glanced at yours for a bit. But it's also called page pool for buffer allocations, and I don't think there's that many ways to implement that really :-) -Daniel > --- > drivers/dma-buf/heaps/Kconfig | 1 + > drivers/dma-buf/heaps/system_heap.c | 68 +++++++++++++++++++++++++++-- > 2 files changed, 65 insertions(+), 4 deletions(-) > > diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig > index ecf65204f714..fa5e1c330cce 100644 > --- a/drivers/dma-buf/heaps/Kconfig > +++ b/drivers/dma-buf/heaps/Kconfig > @@ -4,6 +4,7 @@ config DMABUF_HEAPS_DEFERRED_FREE > config DMABUF_HEAPS_SYSTEM > bool "DMA-BUF System Heap" > depends on DMABUF_HEAPS > + select PAGE_POOL > help > Choose this option to enable the system dmabuf heap. The system heap > is backed by pages from the buddy allocator. If in doubt, say Y. > diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c > index 17e0e9a68baf..885e30894b77 100644 > --- a/drivers/dma-buf/heaps/system_heap.c > +++ b/drivers/dma-buf/heaps/system_heap.c > @@ -20,6 +20,7 @@ > #include <linux/scatterlist.h> > #include <linux/slab.h> > #include <linux/vmalloc.h> > +#include <net/page_pool.h> > > static struct dma_heap *sys_heap; > > @@ -53,6 +54,7 @@ static gfp_t order_flags[] = {HIGH_ORDER_GFP, LOW_ORDER_GFP, LOW_ORDER_GFP}; > */ > static const unsigned int orders[] = {8, 4, 0}; > #define NUM_ORDERS ARRAY_SIZE(orders) > +struct page_pool *pools[NUM_ORDERS]; > > static struct sg_table *dup_sg_table(struct sg_table *table) > { > @@ -281,18 +283,59 @@ static void system_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map) > dma_buf_map_clear(map); > } > > +static int system_heap_clear_pages(struct page **pages, int num, pgprot_t pgprot) > +{ > + void *addr = vmap(pages, num, VM_MAP, pgprot); > + > + if (!addr) > + return -ENOMEM; > + memset(addr, 0, PAGE_SIZE * num); > + vunmap(addr); > + return 0; > +} > + > +static int system_heap_zero_buffer(struct system_heap_buffer *buffer) > +{ > + struct sg_table *sgt = &buffer->sg_table; > + struct sg_page_iter piter; > + struct page *pages[32]; > + int p = 0; > + int ret = 0; > + > + for_each_sgtable_page(sgt, &piter, 0) { > + pages[p++] = sg_page_iter_page(&piter); > + if (p == ARRAY_SIZE(pages)) { > + ret = system_heap_clear_pages(pages, p, PAGE_KERNEL); > + if (ret) > + return ret; > + p = 0; > + } > + } > + if (p) > + ret = system_heap_clear_pages(pages, p, PAGE_KERNEL); > + > + return ret; > +} > + > static void system_heap_dma_buf_release(struct dma_buf *dmabuf) > { > struct system_heap_buffer *buffer = dmabuf->priv; > struct sg_table *table; > struct scatterlist *sg; > - int i; > + int i, j; > + > + /* Zero the buffer pages before adding back to the pool */ > + system_heap_zero_buffer(buffer); > > table = &buffer->sg_table; > for_each_sg(table->sgl, sg, table->nents, i) { > struct page *page = sg_page(sg); > > - __free_pages(page, compound_order(page)); > + for (j = 0; j < NUM_ORDERS; j++) { > + if (compound_order(page) == orders[j]) > + break; > + } > + page_pool_put_full_page(pools[j], page, false); > } > sg_free_table(table); > kfree(buffer); > @@ -322,8 +365,7 @@ static struct page *alloc_largest_available(unsigned long size, > continue; > if (max_order < orders[i]) > continue; > - > - page = alloc_pages(order_flags[i], orders[i]); > + page = page_pool_alloc_pages(pools[i], order_flags[i]); > if (!page) > continue; > return page; > @@ -428,6 +470,24 @@ static const struct dma_heap_ops system_heap_ops = { > static int system_heap_create(void) > { > struct dma_heap_export_info exp_info; > + int i; > + > + for (i = 0; i < NUM_ORDERS; i++) { > + struct page_pool_params pp; > + > + memset(&pp, 0, sizeof(pp)); > + pp.order = orders[i]; > + pools[i] = page_pool_create(&pp); > + > + if (IS_ERR(pools[i])) { > + int j; > + > + pr_err("%s: page pool creation failed!\n", __func__); > + for (j = 0; j < i; j++) > + page_pool_destroy(pools[j]); > + return PTR_ERR(pools[i]); > + } > + } > > exp_info.name = "system"; > exp_info.ops = &system_heap_ops; > -- > 2.17.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel