linux-kernel - [for-next][PATCH 1/4] tracing: Cleanup upper_empty() in pid

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Message-ID: <20250515085127.011811382@goodmis.org>
Date: Thu, 15 May 2025 04:51:10 -0400
From: Steven Rostedt <rostedt@...dmis.org>
To: linux-kernel@...r.kernel.org
Cc: Masami Hiramatsu <mhiramat@...nel.org>,
 Mark Rutland <mark.rutland@....com>,
 Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
 Andrew Morton <akpm@...ux-foundation.org>,
 Yury Norov <yury.norov@...il.com>
Subject: [for-next][PATCH 1/4] tracing: Cleanup upper_empty() in pid_list

From: Yury Norov <yury.norov@...il.com>

Instead of find_first_bit() use the dedicated bitmap_empty(),
and make upper_empty() a nice one-liner.

While there, fix opencoded BITS_PER_TYPE().

Cc: Masami Hiramatsu <mhiramat@...nel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Link: https://lore.kernel.org/20250429195119.620204-1-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@...il.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@...dmis.org>
---
 kernel/trace/pid_list.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/pid_list.c b/kernel/trace/pid_list.c
index c62b9b3cfb3d..090bb5ea4a19 100644
--- a/kernel/trace/pid_list.c
+++ b/kernel/trace/pid_list.c
@@ -81,13 +81,9 @@ static inline bool upper_empty(union upper_chunk *chunk)
 {
 	/*
 	 * If chunk->data has no lower chunks, it will be the same
-	 * as a zeroed bitmask. Use find_first_bit() to test it
-	 * and if it doesn't find any bits set, then the array
-	 * is empty.
+	 * as a zeroed bitmask.
 	 */
-	int bit = find_first_bit((unsigned long *)chunk->data,
-				 sizeof(chunk->data) * 8);
-	return bit >= sizeof(chunk->data) * 8;
+	return bitmap_empty((unsigned long *)chunk->data, BITS_PER_TYPE(chunk->data));
 }
 
 static inline int pid_split(unsigned int pid, unsigned int *upper1,
-- 
2.47.2