linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] Supports to use the default CMA when the device-specified CMA memory is not enough.
@ 2024-06-12  2:38 zhai.he
  2024-06-12  7:20 ` Greg KH
  0 siblings, 1 reply; 4+ messages in thread
From: zhai.he @ 2024-06-12  2:38 UTC (permalink / raw)
  To: akpm; +Cc: sboyd, linux-mm, linux-kernel, stable, zhipeng.wang_1, jindong.yue

From: He Zhai <zhai.he@nxp.com>

In the current code logic, if the device-specified CMA memory
allocation fails, memory will not be allocated from the default CMA area.
This patch will use the default cma region when the device's
specified CMA is not enough.

Signed-off-by: He Zhai <zhai.he@nxp.com>
---
 kernel/dma/contiguous.c | 11 +++++++++--
 mm/cma.c                |  2 +-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 055da410ac71..e45cfb24500f 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -357,8 +357,13 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)
 	/* CMA can be used only in the context which permits sleeping */
 	if (!gfpflags_allow_blocking(gfp))
 		return NULL;
-	if (dev->cma_area)
-		return cma_alloc_aligned(dev->cma_area, size, gfp);
+	if (dev->cma_area) {
+		struct page *page = NULL;
+
+		page = cma_alloc_aligned(dev->cma_area, size, gfp);
+		if (page)
+			return page;
+	}
 	if (size <= PAGE_SIZE)
 		return NULL;
 
@@ -406,6 +411,8 @@ void dma_free_contiguous(struct device *dev, struct page *page, size_t size)
 	if (dev->cma_area) {
 		if (cma_release(dev->cma_area, page, count))
 			return;
+		if (cma_release(dma_contiguous_default_area, page, count))
+			return;
 	} else {
 		/*
 		 * otherwise, page is from either per-numa cma or default cma
diff --git a/mm/cma.c b/mm/cma.c
index 3e9724716bad..f225b3f65bd2 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -495,7 +495,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
 	}
 
 	if (ret && !no_warn) {
-		pr_err_ratelimited("%s: %s: alloc failed, req-size: %lu pages, ret: %d\n",
+		pr_debug("%s: %s: alloc failed, req-size: %lu pages, ret: %d, try to use default cma\n",
 				   __func__, cma->name, count, ret);
 		cma_debug_show_areas(cma);
 	}
-- 
2.34.1



^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2024-06-12  7:47 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-06-12  2:38 [PATCH] Supports to use the default CMA when the device-specified CMA memory is not enough zhai.he
2024-06-12  7:20 ` Greg KH
2024-06-12  7:34   ` [EXT] " Zhai He
2024-06-12  7:47     ` Greg KH

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox