linux-kernel - [PATCH 01/29] x86/boot/e820: Remove inverted boolean logic from the e820_nomerge() function name, rename it to e820_type

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Message-ID: <20250421185210.3372306-2-mingo@kernel.org>
Date: Mon, 21 Apr 2025 20:51:41 +0200
From: Ingo Molnar <mingo@...nel.org>
To: linux-kernel@...r.kernel.org
Cc: Andy Shevchenko <andy@...nel.org>,
	Arnd Bergmann <arnd@...nel.org>,
	Borislav Petkov <bp@...en8.de>,
	Juergen Gross <jgross@...e.com>,
	"H . Peter Anvin" <hpa@...or.com>,
	Kees Cook <keescook@...omium.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Mike Rapoport <rppt@...nel.org>,
	Paul Menzel <pmenzel@...gen.mpg.de>,
	Peter Zijlstra <peterz@...radead.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...nel.org>,
	David Woodhouse <dwmw@...zon.co.uk>
Subject: [PATCH 01/29] x86/boot/e820: Remove inverted boolean logic from the e820_nomerge() function name, rename it to e820_type_mergeable()

It's a bad practice to put inverted logic into function names,
flip it back and rename it to e820_type_mergeable().

Add/update a few comments about this function while at it.

Signed-off-by: Ingo Molnar <mingo@...nel.org>
Cc: Andy Shevchenko <andy@...nel.org>
Cc: Arnd Bergmann <arnd@...nel.org>
Cc: David Woodhouse <dwmw@...zon.co.uk>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Kees Cook <keescook@...omium.org>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Mike Rapoport (Microsoft) <rppt@...nel.org>
---
 arch/x86/kernel/e820.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 9d8dd8deb2a7..4a81f9e94137 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -304,18 +304,22 @@ static int __init cpcompare(const void *a, const void *b)
 	return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);
 }
 
-static bool e820_nomerge(enum e820_type type)
+/*
+ * Can two consecutive E820 entries of this same E820 type be merged?
+ */
+static bool e820_type_mergeable(enum e820_type type)
 {
 	/*
 	 * These types may indicate distinct platform ranges aligned to
-	 * numa node, protection domain, performance domain, or other
+	 * NUMA node, protection domain, performance domain, or other
 	 * boundaries. Do not merge them.
 	 */
 	if (type == E820_TYPE_PRAM)
-		return true;
+		return false;
 	if (type == E820_TYPE_SOFT_RESERVED)
-		return true;
-	return false;
+		return false;
+
+	return true;
 }
 
 int __init e820__update_table(struct e820_table *table)
@@ -393,7 +397,7 @@ int __init e820__update_table(struct e820_table *table)
 		}
 
 		/* Continue building up new map based on this information: */
-		if (current_type != last_type || e820_nomerge(current_type)) {
+		if (current_type != last_type || !e820_type_mergeable(current_type)) {
 			if (last_type) {
 				new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
 				/* Move forward only if the new size was non-zero: */
-- 
2.45.2