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tracing: Use div64_u64() instead of do_div()

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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>
This commit is contained in:
Thorsten Blum 2024-02-25 17:45:08 +01:00 committed by Steven Rostedt (Google)
parent 19f0423fd5
commit d6cb38e108
1 changed files with 2 additions and 3 deletions
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5
kernel/trace/trace_benchmark.c
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@ -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);