Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756955Ab0HCPYa (ORCPT ); Tue, 3 Aug 2010 11:24:30 -0400 Received: from smtp-gw11.han.skanova.net ([81.236.55.20]:40932 "EHLO smtp-gw11.han.skanova.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756293Ab0HCPY0 (ORCPT ); Tue, 3 Aug 2010 11:24:26 -0400 X-Greylist: delayed 378 seconds by postgrey-1.27 at vger.kernel.org; Tue, 03 Aug 2010 11:24:25 EDT Subject: [PATCH 1/3 v2] media: Add a cached version of the contiguous video buffers From: Richard =?ISO-8859-1?Q?R=F6jfors?= To: Linux Media Mailing List Cc: Linux Kernel Mailing List , Mauro Carvalho Chehab , Douglas Schilling Landgraf , Samuel Ortiz Content-Type: text/plain; charset="UTF-8" Date: Tue, 03 Aug 2010 17:18:31 +0200 Message-ID: <1280848711.19898.161.camel@debian> Mime-Version: 1.0 X-Mailer: Evolution 2.30.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8435 Lines: 276 This patch adds another init functions in the videobuf-dma-contig which is named _cached in the end. It creates a buffer factory which allocates buffers using kmalloc and the buffers are cached. A sync callback is added to sync the buffers. Most of the code is reused from the uncached version a bool is added to the memory struct to flag if the buffers are to be cached or not. The reason is that I found the performance of the uncached buffers was too poor on an atom-based X86, so I added this cached version. Signed-off-by: Richard Röjfors --- diff --git a/drivers/media/video/videobuf-dma-contig.c b/drivers/media/video/videobuf-dma-contig.c index 74730c6..a35f65a 100644 --- a/drivers/media/video/videobuf-dma-contig.c +++ b/drivers/media/video/videobuf-dma-contig.c @@ -27,6 +27,7 @@ struct videobuf_dma_contig_memory { u32 magic; void *vaddr; dma_addr_t dma_handle; + bool cached; unsigned long size; int is_userptr; }; @@ -38,6 +39,54 @@ struct videobuf_dma_contig_memory { BUG(); \ } +static int __videobuf_dc_alloc(struct device *dev, + struct videobuf_dma_contig_memory *mem, unsigned long size) +{ + mem->size = size; + if (mem->cached) { + mem->vaddr = kmalloc(mem->size, GFP_KERNEL); + if (mem->vaddr) { + int err; + + mem->dma_handle = dma_map_single(dev, mem->vaddr, + mem->size, DMA_FROM_DEVICE); + err = dma_mapping_error(dev, mem->dma_handle); + if (err) { + dev_err(dev, "dma_map_single failed\n"); + + kfree(mem->vaddr); + mem->vaddr = 0; + return err; + } + } + } else + mem->vaddr = dma_alloc_coherent(dev, mem->size, + &mem->dma_handle, GFP_KERNEL); + + if (!mem->vaddr) { + dev_err(dev, "memory alloc size %ld failed\n", + mem->size); + return -ENOMEM; + } + + dev_dbg(dev, "dma mapped data is at %p (%ld)\n", mem->vaddr, mem->size); + + return 0; +} + +static void __videobuf_dc_free(struct device *dev, + struct videobuf_dma_contig_memory *mem) +{ + if (mem->cached) { + dma_unmap_single(dev, mem->dma_handle, mem->size, + DMA_FROM_DEVICE); + kfree(mem->vaddr); + } else + dma_free_coherent(dev, mem->size, mem->vaddr, mem->dma_handle); + + mem->vaddr = NULL; +} + static void videobuf_vm_open(struct vm_area_struct *vma) { @@ -92,9 +141,7 @@ static void videobuf_vm_close(struct vm_area_struct *vma) dev_dbg(q->dev, "buf[%d] freeing %p\n", i, mem->vaddr); - dma_free_coherent(q->dev, mem->size, - mem->vaddr, mem->dma_handle); - mem->vaddr = NULL; + __videobuf_dc_free(q->dev, mem); } q->bufs[i]->map = NULL; @@ -190,7 +237,7 @@ static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem, return ret; } -static struct videobuf_buffer *__videobuf_alloc(size_t size) +static struct videobuf_buffer *__videobuf_alloc(size_t size, bool cached) { struct videobuf_dma_contig_memory *mem; struct videobuf_buffer *vb; @@ -199,11 +246,22 @@ static struct videobuf_buffer *__videobuf_alloc(size_t size) if (vb) { mem = vb->priv = ((char *)vb) + size; mem->magic = MAGIC_DC_MEM; + mem->cached = cached; } return vb; } +static struct videobuf_buffer *__videobuf_alloc_uncached(size_t size) +{ + return __videobuf_alloc(size, false); +} + +static struct videobuf_buffer *__videobuf_alloc_cached(size_t size) +{ + return __videobuf_alloc(size, true); +} + static void *__videobuf_to_vaddr(struct videobuf_buffer *buf) { struct videobuf_dma_contig_memory *mem = buf->priv; @@ -241,17 +299,8 @@ static int __videobuf_iolock(struct videobuf_queue *q, return videobuf_dma_contig_user_get(mem, vb); /* allocate memory for the read() method */ - mem->size = PAGE_ALIGN(vb->size); - mem->vaddr = dma_alloc_coherent(q->dev, mem->size, - &mem->dma_handle, GFP_KERNEL); - if (!mem->vaddr) { - dev_err(q->dev, "dma_alloc_coherent %ld failed\n", - mem->size); + if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size))) return -ENOMEM; - } - - dev_dbg(q->dev, "dma_alloc_coherent data is at %p (%ld)\n", - mem->vaddr, mem->size); break; case V4L2_MEMORY_OVERLAY: default: @@ -263,6 +312,19 @@ static int __videobuf_iolock(struct videobuf_queue *q, return 0; } +static int __videobuf_sync(struct videobuf_queue *q, + struct videobuf_buffer *buf) +{ + struct videobuf_dma_contig_memory *mem = buf->priv; + BUG_ON(!mem); + MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); + + dma_sync_single_for_cpu(q->dev, mem->dma_handle, mem->size, + DMA_FROM_DEVICE); + + return 0; +} + static int __videobuf_mmap_mapper(struct videobuf_queue *q, struct videobuf_buffer *buf, struct vm_area_struct *vma) @@ -290,30 +352,22 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q, BUG_ON(!mem); MAGIC_CHECK(mem->magic, MAGIC_DC_MEM); - mem->size = PAGE_ALIGN(buf->bsize); - mem->vaddr = dma_alloc_coherent(q->dev, mem->size, - &mem->dma_handle, GFP_KERNEL); - if (!mem->vaddr) { - dev_err(q->dev, "dma_alloc_coherent size %ld failed\n", - mem->size); + if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize))) goto error; - } - dev_dbg(q->dev, "dma_alloc_coherent data is at addr %p (size %ld)\n", - mem->vaddr, mem->size); /* Try to remap memory */ size = vma->vm_end - vma->vm_start; size = (size < mem->size) ? size : mem->size; - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + if (!mem->cached) + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); retval = remap_pfn_range(vma, vma->vm_start, mem->dma_handle >> PAGE_SHIFT, size, vma->vm_page_prot); if (retval) { dev_err(q->dev, "mmap: remap failed with error %d. ", retval); - dma_free_coherent(q->dev, mem->size, - mem->vaddr, mem->dma_handle); + __videobuf_dc_free(q->dev, mem); goto error; } @@ -338,8 +392,18 @@ error: static struct videobuf_qtype_ops qops = { .magic = MAGIC_QTYPE_OPS, - .alloc = __videobuf_alloc, + .alloc = __videobuf_alloc_uncached, + .iolock = __videobuf_iolock, + .mmap_mapper = __videobuf_mmap_mapper, + .vaddr = __videobuf_to_vaddr, +}; + +static struct videobuf_qtype_ops qops_cached = { + .magic = MAGIC_QTYPE_OPS, + + .alloc = __videobuf_alloc_cached, .iolock = __videobuf_iolock, + .sync = __videobuf_sync, .mmap_mapper = __videobuf_mmap_mapper, .vaddr = __videobuf_to_vaddr, }; @@ -358,6 +422,20 @@ void videobuf_queue_dma_contig_init(struct videobuf_queue *q, } EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init); +void videobuf_queue_dma_contig_init_cached(struct videobuf_queue *q, + const struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv) +{ + videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize, + priv, &qops_cached); +} +EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init_cached); + dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf) { struct videobuf_dma_contig_memory *mem = buf->priv; @@ -394,9 +472,7 @@ void videobuf_dma_contig_free(struct videobuf_queue *q, return; } - /* read() method */ - dma_free_coherent(q->dev, mem->size, mem->vaddr, mem->dma_handle); - mem->vaddr = NULL; + __videobuf_dc_free(q->dev, mem); } EXPORT_SYMBOL_GPL(videobuf_dma_contig_free); diff --git a/include/media/videobuf-dma-contig.h b/include/media/videobuf-dma-contig.h index ebaa9bc..43b94cd 100644 --- a/include/media/videobuf-dma-contig.h +++ b/include/media/videobuf-dma-contig.h @@ -25,6 +25,15 @@ void videobuf_queue_dma_contig_init(struct videobuf_queue *q, unsigned int msize, void *priv); +void videobuf_queue_dma_contig_init_cached(struct videobuf_queue *q, + const struct videobuf_queue_ops *ops, + struct device *dev, + spinlock_t *irqlock, + enum v4l2_buf_type type, + enum v4l2_field field, + unsigned int msize, + void *priv); + dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf); void videobuf_dma_contig_free(struct videobuf_queue *q, struct videobuf_buffer *buf); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/