linux-kernel - [PATCH v4 32/40] microblaze: optimize get_mmu

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Date: Thu, 20 Jun 2024 10:56:55 -0700
From: Yury Norov <yury.norov@...il.com>
To: linux-kernel@...r.kernel.org,
	Michal Simek <monstr@...str.eu>,
	Yury Norov <yury.norov@...il.com>
Cc: Alexey Klimov <alexey.klimov@...aro.org>,
	Bart Van Assche <bvanassche@....org>,
	Jan Kara <jack@...e.cz>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Matthew Wilcox <willy@...radead.org>,
	Mirsad Todorovac <mirsad.todorovac@....unizg.hr>,
	Rasmus Villemoes <linux@...musvillemoes.dk>,
	Sergey Shtylyov <s.shtylyov@....ru>
Subject: [PATCH v4 32/40] microblaze: optimize get_mmu_context()

Simplify get_mmu_context() by using find_and_set_bit_wrap().

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 arch/microblaze/include/asm/mmu_context_mm.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/microblaze/include/asm/mmu_context_mm.h b/arch/microblaze/include/asm/mmu_context_mm.h
index c2c77f708455..d4d1e80b3b66 100644
--- a/arch/microblaze/include/asm/mmu_context_mm.h
+++ b/arch/microblaze/include/asm/mmu_context_mm.h
@@ -9,6 +9,7 @@
 #define _ASM_MICROBLAZE_MMU_CONTEXT_H
 
 #include <linux/atomic.h>
+#include <linux/find_atomic.h>
 #include <linux/mm_types.h>
 #include <linux/sched.h>
 
@@ -82,12 +83,11 @@ static inline void get_mmu_context(struct mm_struct *mm)
 		return;
 	while (atomic_dec_if_positive(&nr_free_contexts) < 0)
 		steal_context();
-	ctx = next_mmu_context;
-	while (test_and_set_bit(ctx, context_map)) {
-		ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx);
-		if (ctx > LAST_CONTEXT)
-			ctx = 0;
-	}
+
+	do {
+		ctx = find_and_set_bit_wrap(context_map, LAST_CONTEXT + 1, next_mmu_context);
+	} while (ctx > LAST_CONTEXT);
+
 	next_mmu_context = (ctx + 1) & LAST_CONTEXT;
 	mm->context = ctx;
 	context_mm[ctx] = mm;
-- 
2.43.0