linux-kernel - [PATCH v1 1/1] lib/vsprinf: Deduplicate special hex number specifier data

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Message-ID: <20251113093015.2283883-1-andriy.shevchenko@linux.intel.com>
Date: Thu, 13 Nov 2025 10:30:15 +0100
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: linux-kernel@...r.kernel.org
Cc: Andrew Morton <akpm@...ux-foundation.org>,
	Petr Mladek <pmladek@...e.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Sergey Senozhatsky <senozhatsky@...omium.org>
Subject: [PATCH v1 1/1] lib/vsprinf: Deduplicate special hex number specifier data

Two functions use the same specifier data for the special hex number.
Almost the same as the field width is calculated on the size of the
given type. Due to that, make a compound literal macro in order to
deduplicate the rest.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 lib/vsprintf.c | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 3143496f6bf8..51a88b3f5b52 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -582,17 +582,18 @@ char *number(char *buf, char *end, unsigned long long num,
 	return buf;
 }
 
+#define special_hex_spec(size)					\
+(struct printf_spec) {						\
+	.field_width = 2 + 2 * (size),		/* 0x + hex */	\
+	.flags = SPECIAL | SMALL | ZEROPAD,			\
+	.base = 16,						\
+	.precision = -1,					\
+}
+
 static noinline_for_stack
 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 {
-	struct printf_spec spec;
-
-	spec.field_width = 2 + 2 * size;	/* 0x + hex */
-	spec.flags = SPECIAL | SMALL | ZEROPAD;
-	spec.base = 16;
-	spec.precision = -1;
-
-	return number(buf, end, num, spec);
+	return number(buf, end, num, special_hex_spec(size));
 }
 
 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
@@ -1164,18 +1165,11 @@ char *range_string(char *buf, char *end, const struct range *range,
 	char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")];
 	char *p = sym, *pend = sym + sizeof(sym);
 
-	struct printf_spec range_spec = {
-		.field_width = 2 + 2 * sizeof(range->start), /* 0x + 2 * 8 */
-		.flags = SPECIAL | SMALL | ZEROPAD,
-		.base = 16,
-		.precision = -1,
-	};
-
 	if (check_pointer(&buf, end, range, spec))
 		return buf;
 
 	p = string_nocheck(p, pend, "[range ", default_str_spec);
-	p = hex_range(p, pend, range->start, range->end, range_spec);
+	p = hex_range(p, pend, range->start, range->end, special_hex_spec(sizeof(range->start)));
 	*p++ = ']';
 	*p = '\0';
 
-- 
2.50.1