patches/old/mm-cma-print-total-and-used-count-in-cma_alloc.patch

From: gaoxiang17 <gaoxiang17@xiaomi.com>
Subject: mm/cma: print total and used count in cma_alloc()
Date: Thu, 26 Sep 2024 20:00:49 +0800

To better understand cma area during debugging.

before:
[   24.407814] cma: cma_alloc(cma (____ptrval____), name: reserved, count 1, align 0)
[   24.413397] cma: cma_alloc(cma (____ptrval____), name: reserved, count 1, align 0)
[   24.415886] cma: cma_alloc(cma (____ptrval____), name: reserved, count 1, align 0)

after:
[   24.097989] cma: cma_alloc(cma (____ptrval____), name: reserved, total count 16384, used count: 64, request count 1, align 0)
[   24.104260] cma: cma_alloc(cma (____ptrval____), name: reserved, total count 16384, used count: 65, request count 1, align 0)
[   24.107504] cma: cma_alloc(cma (____ptrval____), name: reserved, total count 16384, used count: 66, request count 1, align 0)

Link: https://lkml.kernel.org/r/20240926120049.321514-1-gxxa03070307@gmail.com
Signed-off-by: gaoxiang17 <gaoxiang17@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/cma.c |   15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

--- a/mm/cma.c~mm-cma-print-total-and-used-count-in-cma_alloc
+++ a/mm/cma.c
@@ -402,6 +402,17 @@ static void cma_debug_show_areas(struct
 	spin_unlock_irq(&cma->lock);
 }
 
+static unsigned long cma_get_used(struct cma *cma)
+{
+	unsigned long used;
+
+	spin_lock_irq(&cma->lock);
+	used = bitmap_weight(cma->bitmap, (int)cma_bitmap_maxno(cma));
+	spin_unlock_irq(&cma->lock);
+
+	return used << cma->order_per_bit;
+}
+
 static struct page *__cma_alloc(struct cma *cma, unsigned long count,
 				unsigned int align, gfp_t gfp)
 {
@@ -419,8 +430,8 @@ static struct page *__cma_alloc(struct c
 	if (!cma || !cma->count || !cma->bitmap)
 		return page;
 
-	pr_debug("%s(cma %p, name: %s, count %lu, align %d)\n", __func__,
-		(void *)cma, cma->name, count, align);
+	pr_debug("%s(cma %p, name: %s, total count %lu, used count: %lu, request count %lu, align %d)\n", __func__,
+		(void *)cma, cma->name, cma->count, cma_get_used(cma), count, align);
 
 	if (!count)
 		return page;
_