The relative functions is copy from bcc tools source code: libbpf-tools/trace_helpers.c. URL: https://github.com/iovisor/bcc.git Log2 histogram can display the change of the collected data more conveniently. Signed-off-by: Xin Hao <xhao@xxxxxxxxxxxxxxxxx> --- samples/bpf/common.h | 67 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 samples/bpf/common.h diff --git a/samples/bpf/common.h b/samples/bpf/common.h new file mode 100644 index 000000000000..ec60fb665544 --- /dev/null +++ b/samples/bpf/common.h @@ -0,0 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ + +#define min(x, y) ({ \ + typeof(x) _min1 = (x); \ + typeof(y) _min2 = (y); \ + (void) (&_min1 == &_min2); \ + _min1 < _min2 ? _min1 : _min2; }) + +static void print_stars(unsigned int val, unsigned int val_max, int width) +{ + int num_stars, num_spaces, i; + bool need_plus; + + num_stars = min(val, val_max) * width / val_max; + num_spaces = width - num_stars; + need_plus = val > val_max; + + for (i = 0; i < num_stars; i++) + printf("*"); + for (i = 0; i < num_spaces; i++) + printf(" "); + if (need_plus) + printf("+"); +} + +static void print_log2_hist(unsigned int *vals, int vals_size, char *val_type) +{ + int stars_max = 40, idx_max = -1; + unsigned int val, val_max = 0; + unsigned long long low, high; + int stars, width, i; + + for (i = 0; i < vals_size; i++) { + val = vals[i]; + if (val > 0) + idx_max = i; + if (val > val_max) + val_max = val; + } + + if (idx_max < 0) + return; + + printf("%*s%-*s : count distribution\n", idx_max <= 32 ? 5 : 15, "", + idx_max <= 32 ? 19 : 29, val_type); + if (idx_max <= 32) + stars = stars_max; + else + stars = stars_max / 2; + + for (i = 0; i <= idx_max; i++) { + low = (1ULL << (i + 1)) >> 1; + high = (1ULL << (i + 1)) - 1; + if (low == high) + low -= 1; + val = vals[i]; + width = idx_max <= 32 ? 10 : 20; + printf("%*lld -> %-*lld : %-8d |", width, low, width, high, val); + print_stars(val, val_max, stars); + printf("|\n"); + } +} -- 2.28.0
