7 files changed, 63 insertions, 2 deletions

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 6676c2dd6dcb..1cb3d9b540e9 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -44,6 +44,7 @@ perf-y += is_printable_array.o
 perf-y += bitmap.o
 perf-y += perf-hooks.o
 perf-y += clang.o
+perf-y += unit_number__scnprintf.o
 
 $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c tests/Build
         $(call rule_mkdir)
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index a77dcc0d24e3..37e326bfd2dc 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -247,6 +247,10 @@ static struct test generic_tests[] = {
                 }
         },
         {
+                .desc = "unit_number__scnprintf",
+                .func = test__unit_number__scnprint,
+        },
+        {
                 .func = NULL,
         },
 };
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index a512f0c8ff5b..1fa9b9d83aa5 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -96,6 +96,7 @@ int test__perf_hooks(int subtest);
 int test__clang(int subtest);
 const char *test__clang_subtest_get_desc(int subtest);
 int test__clang_subtest_get_nr(void);
+int test__unit_number__scnprint(int subtest);
 
 #if defined(__arm__) || defined(__aarch64__)
 #ifdef HAVE_DWARF_UNWIND_SUPPORT
diff --git a/tools/perf/tests/unit_number__scnprintf.c b/tools/perf/tests/unit_number__scnprintf.c
new file mode 100644
index 000000000000..623c2aa53c4a
--- /dev/null
+++ b/tools/perf/tests/unit_number__scnprintf.c
@@ -0,0 +1,37 @@
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include "tests.h"
+#include "util.h"
+#include "debug.h"
+
+int test__unit_number__scnprint(int subtest __maybe_unused)
+{
+        struct {
+                u64              n;
+                const char      *str;
+        } test[] = {
+                { 1,                    "1B"    },
+                { 10*1024,              "10K"   },
+                { 20*1024*1024,         "20M"   },
+                { 30*1024*1024*1024ULL, "30G"   },
+                { 0,                    "0B"    },
+                { 0,                    NULL    },
+        };
+        unsigned i = 0;
+
+        while (test[i].str) {
+                char buf[100];
+
+                unit_number__scnprintf(buf, sizeof(buf), test[i].n);
+
+                pr_debug("n %" PRIu64 ", str '%s', buf '%s'\n",
+                         test[i].n, test[i].str, buf);
+
+                if (strcmp(test[i].str, buf))
+                        return TEST_FAIL;
+
+                i++;
+        }
+
+        return TEST_OK;
+}
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 23e6f33edcf2..dc4df3d2660e 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1224,12 +1224,16 @@ static long parse_pages_arg(const char *str, unsigned long min,
         if (pages == 0 && min == 0) {
                 /* leave number of pages at 0 */
         } else if (!is_power_of_2(pages)) {
+                char buf[100];
+
                 /* round pages up to next power of 2 */
                 pages = roundup_pow_of_two(pages);
                 if (!pages)
                         return -EINVAL;
-                pr_info("rounding mmap pages size to %lu bytes (%lu pages)\n",
-                        pages * page_size, pages);
+
+                unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
+                pr_info("rounding mmap pages size to %s (%lu pages)\n",
+                        buf, pages);
         }
 
         if (pages > max)
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 9ddd98827d12..bf29aed16bd6 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -789,3 +789,16 @@ int is_printable_array(char *p, unsigned int len)
         }
         return 1;
 }
+
+int unit_number__scnprintf(char *buf, size_t size, u64 n)
+{
+        char unit[4] = "BKMG";
+        int i = 0;
+
+        while (((n / 1024) > 1) && (i < 3)) {
+                n /= 1024;
+                i++;
+        }
+
+        return scnprintf(buf, size, "%" PRIu64 "%c", n, unit[i]);
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 1d639e38aa82..6e8be174ec0b 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -363,4 +363,5 @@ int is_printable_array(char *p, unsigned int len);
 
 int timestamp__scnprintf_usec(u64 timestamp, char *buf, size_t sz);
 
+int unit_number__scnprintf(char *buf, size_t size, u64 n);
 #endif /* GIT_COMPAT_UTIL_H */