Re: ALSA on MIPS platform

[Takashi Iwai <tiwai@suse.de>]

At Mon, 30 Jan 2006 18:56:08 +0900 (JST),
Atsushi Nemoto wrote:
> 
> >>>>> On Fri, 27 Jan 2006 16:57:49 +0100, Takashi Iwai <tiwai@suse.de> said:
> hugh> Yes, mark_pages() and unmark_pages() can just be removed as soon
> hugh> as you like.
> 
> >> When I tried undefining NEED_RESERVE_PAGES for MIPS on 2.6.13,
> >> something did not work (I can not remember details...).  But it seems
> >> things have been changed in 2.6.15.  I'll try again.  Thanks.
> 
> tiwai> Yes, it was changed pretty much.
> 
> I undefined NEED_RESERVE_PAGES on 2.6.15 and it seems OK on MIPS.
> Thank you.

Well, as Hugu pointed out, that page reservation plays no longer any
role.  The patch below should work too on 2.6.15 or later.


Takashi


--- linux/sound/core/memalloc.c	23 Jan 2006 15:53:15 -0000	1.52
+++ linux/sound/core/memalloc.c	30 Jan 2006 10:16:31 -0000
@@ -141,10 +141,6 @@
 
 #endif /* arch */
 
-#if ! defined(__arm__)
-#define NEED_RESERVE_PAGES
-#endif
-
 /*
  *
  *  Generic memory allocators
@@ -163,20 +159,6 @@
 	snd_allocated_pages -= 1 << order;
 }
 
-static void mark_pages(struct page *page, int order)
-{
-	struct page *last_page = page + (1 << order);
-	while (page < last_page)
-		SetPageReserved(page++);
-}
-
-static void unmark_pages(struct page *page, int order)
-{
-	struct page *last_page = page + (1 << order);
-	while (page < last_page)
-		ClearPageReserved(page++);
-}
-
 /**
  * snd_malloc_pages - allocate pages with the given size
  * @size: the size to allocate in bytes
@@ -195,10 +177,8 @@
 	snd_assert(gfp_flags != 0, return NULL);
 	gfp_flags |= __GFP_COMP;	/* compound page lets parts be mapped */
 	pg = get_order(size);
-	if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL) {
-		mark_pages(virt_to_page(res), pg);
+	if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL)
 		inc_snd_pages(pg);
-	}
 	return res;
 }
 
@@ -217,7 +197,6 @@
 		return;
 	pg = get_order(size);
 	dec_snd_pages(pg);
-	unmark_pages(virt_to_page(ptr), pg);
 	free_pages((unsigned long) ptr, pg);
 }
 
@@ -242,12 +221,8 @@
 		| __GFP_NORETRY /* don't trigger OOM-killer */
 		| __GFP_NOWARN; /* no stack trace print - this call is non-critical */
 	res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
-	if (res != NULL) {
-#ifdef NEED_RESERVE_PAGES
-		mark_pages(virt_to_page(res), pg); /* should be dma_to_page() */
-#endif
+	if (res != NULL)
 		inc_snd_pages(pg);
-	}
 
 	return res;
 }
@@ -262,9 +237,6 @@
 		return;
 	pg = get_order(size);
 	dec_snd_pages(pg);
-#ifdef NEED_RESERVE_PAGES
-	unmark_pages(virt_to_page(ptr), pg); /* should be dma_to_page() */
-#endif
 	dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
 }