linux-kernel - [PATCH] x86/mm: Replace manual bounding with clamp()

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Message-Id: <20250207164218.8247-1-qasdev00@gmail.com>
Date: Fri,  7 Feb 2025 16:42:18 +0000
From: Qasim Ijaz <qasdev00@...il.com>
To: dave.hansen@...ux.intel.com,
	luto@...nel.org,
	peterz@...radead.org,
	tglx@...utronix.de,
	mingo@...hat.com,
	bp@...en8.de,
	hpa@...or.com
Cc: x86@...nel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] x86/mm: Replace manual bounding with clamp()

Rather than manually bounding gap between gap_min and gap_max,
use the clamp() macro to make the code more concise.

Signed-off-by: Qasim Ijaz <qasdev00@...il.com>
---
 arch/x86/mm/mmap.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index b8a6ffffb451..5ed2109211da 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -84,7 +84,6 @@ static unsigned long mmap_base(unsigned long rnd, unsigned long task_size,
 {
 	unsigned long gap = rlim_stack->rlim_cur;
 	unsigned long pad = stack_maxrandom_size(task_size) + stack_guard_gap;
-	unsigned long gap_min, gap_max;
 
 	/* Values close to RLIM_INFINITY can overflow. */
 	if (gap + pad > gap)
@@ -94,13 +93,7 @@ static unsigned long mmap_base(unsigned long rnd, unsigned long task_size,
 	 * Top of mmap area (just below the process stack).
 	 * Leave an at least ~128 MB hole with possible stack randomization.
 	 */
-	gap_min = SIZE_128M;
-	gap_max = (task_size / 6) * 5;
-
-	if (gap < gap_min)
-		gap = gap_min;
-	else if (gap > gap_max)
-		gap = gap_max;
+	gap = clamp(gap, SIZE_128M, (task_size / 6) * 5);
 
 	return PAGE_ALIGN(task_size - gap - rnd);
 }
-- 
2.39.5