From: Thorsten Blum <thorsten.blum@toblux.com>
Date: Sun, 25 Feb 2024 16:45:08 +0000 (+0100)
Subject: tracing: Use div64_u64() instead of do_div()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d6cb38e10810743addf8cac0b277861d614de1e9;p=linux.git

tracing: Use div64_u64() instead of do_div()

Fixes Coccinelle/coccicheck warnings reported by do_div.cocci.

Compared to do_div(), div64_u64() does not implicitly cast the divisor and
does not unnecessarily calculate the remainder.

Link: https://lore.kernel.org/linux-trace-kernel/20240225164507.232942-2-thorsten.blum@toblux.com

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---

diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c
index 54d5fa35c90ab..811b08439406a 100644
--- a/kernel/trace/trace_benchmark.c
+++ b/kernel/trace/trace_benchmark.c
@@ -92,7 +92,6 @@ static void trace_do_benchmark(void)
 	bm_total += delta;
 	bm_totalsq += delta * delta;
 
-
 	if (bm_cnt > 1) {
 		/*
 		 * Apply Welford's method to calculate standard deviation:
@@ -105,7 +104,7 @@ static void trace_do_benchmark(void)
 		stddev = 0;
 
 	delta = bm_total;
-	do_div(delta, bm_cnt);
+	delta = div64_u64(delta, bm_cnt);
 	avg = delta;
 
 	if (stddev > 0) {
@@ -127,7 +126,7 @@ static void trace_do_benchmark(void)
 			seed = stddev;
 			if (!last_seed)
 				break;
-			do_div(seed, last_seed);
+			seed = div64_u64(seed, last_seed);
 			seed += last_seed;
 			do_div(seed, 2);
 		} while (i++ < 10 && last_seed != seed);