linux-kernel - [PATCH] mm: Reduce mem_dump

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Date:   Fri, 12 Feb 2021 15:40:59 -0800
From:   Joe Perches <joe@...ches.com>
To:     Andrew Morton <akpm@...ux-foundation.org>
Cc:     linux-mm <linux-mm@...ck.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH] mm: Reduce mem_dump_obj() object size

Simplify the code by using a temporary and reduce the object size
by using a single call to pr_cont().  Reverse a test and unindent
a block too.

$ size mm/util.o* (defconfig x86-64)
   text	   data	    bss	    dec	    hex	filename
   7419	    372	     40	   7831	   1e97	mm/util.o.new
   7477	    372	     40	   7889	   1ed1	mm/util.o.old

Signed-off-by: Joe Perches <joe@...ches.com>
---
 mm/util.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/mm/util.c b/mm/util.c
index c37e24d5fa43..143c627fb3e8 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -997,22 +997,26 @@ int __weak memcmp_pages(struct page *page1, struct page *page2)
  */
 void mem_dump_obj(void *object)
 {
+	const char *type;
+
 	if (kmem_valid_obj(object)) {
 		kmem_dump_obj(object);
 		return;
 	}
+
 	if (vmalloc_dump_obj(object))
 		return;
-	if (!virt_addr_valid(object)) {
-		if (object == NULL)
-			pr_cont(" NULL pointer.\n");
-		else if (object == ZERO_SIZE_PTR)
-			pr_cont(" zero-size pointer.\n");
-		else
-			pr_cont(" non-paged memory.\n");
-		return;
-	}
-	pr_cont(" non-slab/vmalloc memory.\n");
+
+	if (virt_addr_valid(object))
+		type = "non-slab/vmalloc memory";
+	else if (object == NULL)
+		type = "NULL pointer";
+	else if (object == ZERO_SIZE_PTR)
+		type = "zero-size pointer";
+	else
+		type = "non-paged memory";
+
+	pr_cont(" %s\n", type);
 }
 EXPORT_SYMBOL_GPL(mem_dump_obj);
 #endif