perf bench mem: Defer type munging of size to float

Do type conversion to double at the point of use.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20250917152418.4077386-3-ankur.a.arora@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: terminus

tools/perf/bench/mem-functions.c

@@ -139,7 +139,7 @@ struct bench_mem_info {
 	bool alloc_src;
 };
 
-static void __bench_mem_function(struct bench_mem_info *info, int r_idx, size_t size, double size_total)
+static void __bench_mem_function(struct bench_mem_info *info, int r_idx, size_t size, size_t size_total)
 {
 	const struct function *r = &info->functions[r_idx];
 	double result_bps = 0.0;
@@ -165,18 +165,18 @@ static void __bench_mem_function(struct bench_mem_info *info, int r_idx, size_t
 	switch (bench_format) {
 	case BENCH_FORMAT_DEFAULT:
 		if (use_cycles) {
-			printf(" %14lf cycles/byte\n", (double)rt.cycles/size_total);
+			printf(" %14lf cycles/byte\n", (double)rt.cycles/(double)size_total);
 		} else {
-			result_bps = size_total/timeval2double(&rt.tv);
+			result_bps = (double)size_total/timeval2double(&rt.tv);
 			print_bps(result_bps);
 		}
 		break;
 
 	case BENCH_FORMAT_SIMPLE:
 		if (use_cycles) {
-			printf("%lf\n", (double)rt.cycles/size_total);
+			printf("%lf\n", (double)rt.cycles/(double)size_total);
 		} else {
-			result_bps = size_total/timeval2double(&rt.tv);
+			result_bps = (double)size_total/timeval2double(&rt.tv);
 			printf("%lf\n", result_bps);
 		}
 		break;
@@ -199,7 +199,7 @@ static int bench_mem_common(int argc, const char **argv, struct bench_mem_info *
 {
 	int i;
 	size_t size;
-	double size_total;
+	size_t size_total;
 
 	argc = parse_options(argc, argv, options, info->usage, 0);
 
@@ -212,7 +212,7 @@ static int bench_mem_common(int argc, const char **argv, struct bench_mem_info *
 	}
 
 	size = (size_t)perf_atoll((char *)size_str);
-	size_total = (double)size * nr_loops;
+	size_total = size * nr_loops;
 
 	if ((s64)size <= 0) {
 		fprintf(stderr, "Invalid size:%s\n", size_str);