blob: 4e4554e0c5d3c82fb8aa50ff4f740770077cf87e [file] [log] [blame]
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/*
* filetop Trace file reads/writes by process.
* Copyright (c) 2021 Hengqi Chen
*
* Based on filetop(8) from BCC by Brendan Gregg.
* 17-Jul-2021 Hengqi Chen Created this.
*/
#include <argp.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <bpf/libbpf.h>
#include <bpf/bpf.h>
#include "filetop.h"
#include "filetop.skel.h"
#include "trace_helpers.h"
#define warn(...) fprintf(stderr, __VA_ARGS__)
#define OUTPUT_ROWS_LIMIT 10240
enum SORT {
ALL,
READS,
WRITES,
RBYTES,
WBYTES,
};
static volatile sig_atomic_t exiting = 0;
static pid_t target_pid = 0;
static bool clear_screen = true;
static bool regular_file_only = true;
static int output_rows = 20;
static int sort_by = ALL;
static int interval = 1;
static int count = 99999999;
static bool verbose = false;
const char *argp_program_version = "filetop 0.1";
const char *argp_program_bug_address =
"https://github.com/iovisor/bcc/tree/master/libbpf-tools";
const char argp_program_doc[] =
"Trace file reads/writes by process.\n"
"\n"
"USAGE: filetop [-h] [-p PID] [interval] [count]\n"
"\n"
"EXAMPLES:\n"
" filetop # file I/O top, refresh every 1s\n"
" filetop -p 1216 # only trace PID 1216\n"
" filetop 5 10 # 5s summaries, 10 times\n";
static const struct argp_option opts[] = {
{ "pid", 'p', "PID", 0, "Process ID to trace" },
{ "noclear", 'C', NULL, 0, "Don't clear the screen" },
{ "all", 'a', NULL, 0, "Include special files" },
{ "sort", 's', "SORT", 0, "Sort columns, default all [all, reads, writes, rbytes, wbytes]" },
{ "rows", 'r', "ROWS", 0, "Maximum rows to print, default 20" },
{ "verbose", 'v', NULL, 0, "Verbose debug output" },
{ NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
{},
};
static error_t parse_arg(int key, char *arg, struct argp_state *state)
{
long pid, rows;
static int pos_args;
switch (key) {
case 'p':
errno = 0;
pid = strtol(arg, NULL, 10);
if (errno || pid <= 0) {
warn("invalid PID: %s\n", arg);
argp_usage(state);
}
target_pid = pid;
break;
case 'C':
clear_screen = false;
break;
case 'a':
regular_file_only = false;
break;
case 's':
if (!strcmp(arg, "all")) {
sort_by = ALL;
} else if (!strcmp(arg, "reads")) {
sort_by = READS;
} else if (!strcmp(arg, "writes")) {
sort_by = WRITES;
} else if (!strcmp(arg, "rbytes")) {
sort_by = RBYTES;
} else if (!strcmp(arg, "wbytes")) {
sort_by = WBYTES;
} else {
warn("invalid sort method: %s\n", arg);
argp_usage(state);
}
break;
case 'r':
errno = 0;
rows = strtol(arg, NULL, 10);
if (errno || rows <= 0) {
warn("invalid rows: %s\n", arg);
argp_usage(state);
}
output_rows = rows;
if (output_rows > OUTPUT_ROWS_LIMIT)
output_rows = OUTPUT_ROWS_LIMIT;
break;
case 'v':
verbose = true;
break;
case 'h':
argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
break;
case ARGP_KEY_ARG:
errno = 0;
if (pos_args == 0) {
interval = strtol(arg, NULL, 10);
if (errno || interval <= 0) {
warn("invalid interval\n");
argp_usage(state);
}
} else if (pos_args == 1) {
count = strtol(arg, NULL, 10);
if (errno || count <= 0) {
warn("invalid count\n");
argp_usage(state);
}
} else {
warn("unrecognized positional argument: %s\n", arg);
argp_usage(state);
}
pos_args++;
break;
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
{
if (level == LIBBPF_DEBUG && !verbose)
return 0;
return vfprintf(stderr, format, args);
}
static void sig_int(int signo)
{
exiting = 1;
}
static int sort_column(const void *obj1, const void *obj2)
{
struct file_stat *s1 = (struct file_stat *)obj1;
struct file_stat *s2 = (struct file_stat *)obj2;
if (sort_by == READS) {
return s2->reads - s1->reads;
} else if (sort_by == WRITES) {
return s2->writes - s1->writes;
} else if (sort_by == RBYTES) {
return s2->read_bytes - s1->read_bytes;
} else if (sort_by == WBYTES) {
return s2->write_bytes - s1->write_bytes;
} else {
return (s2->reads + s2->writes + s2->read_bytes + s2->write_bytes)
- (s1->reads + s1->writes + s1->read_bytes + s1->write_bytes);
}
}
static int print_stat(struct filetop_bpf *obj)
{
FILE *f;
time_t t;
struct tm *tm;
char ts[16], buf[256];
struct file_id key, *prev_key = NULL;
static struct file_stat values[OUTPUT_ROWS_LIMIT];
int n, i, err = 0, rows = 0;
int fd = bpf_map__fd(obj->maps.entries);
f = fopen("/proc/loadavg", "r");
if (f) {
time(&t);
tm = localtime(&t);
strftime(ts, sizeof(ts), "%H:%M:%S", tm);
memset(buf, 0, sizeof(buf));
n = fread(buf, 1, sizeof(buf), f);
if (n)
printf("%8s loadavg: %s\n", ts, buf);
fclose(f);
}
printf("%-7s %-16s %-6s %-6s %-7s %-7s %1s %s\n",
"TID", "COMM", "READS", "WRITES", "R_Kb", "W_Kb", "T", "FILE");
while (1) {
err = bpf_map_get_next_key(fd, prev_key, &key);
if (err) {
if (errno == ENOENT) {
err = 0;
break;
}
warn("bpf_map_get_next_key failed: %s\n", strerror(errno));
return err;
}
err = bpf_map_lookup_elem(fd, &key, &values[rows++]);
if (err) {
warn("bpf_map_lookup_elem failed: %s\n", strerror(errno));
return err;
}
prev_key = &key;
}
qsort(values, rows, sizeof(struct file_stat), sort_column);
rows = rows < output_rows ? rows : output_rows;
for (i = 0; i < rows; i++)
printf("%-7d %-16s %-6lld %-6lld %-7lld %-7lld %c %s\n",
values[i].tid, values[i].comm, values[i].reads, values[i].writes,
values[i].read_bytes / 1024, values[i].write_bytes / 1024,
values[i].type, values[i].filename);
printf("\n");
prev_key = NULL;
while (1) {
err = bpf_map_get_next_key(fd, prev_key, &key);
if (err) {
if (errno == ENOENT) {
err = 0;
break;
}
warn("bpf_map_get_next_key failed: %s\n", strerror(errno));
return err;
}
err = bpf_map_delete_elem(fd, &key);
if (err) {
warn("bpf_map_delete_elem failed: %s\n", strerror(errno));
return err;
}
prev_key = &key;
}
return err;
}
int main(int argc, char **argv)
{
static const struct argp argp = {
.options = opts,
.parser = parse_arg,
.doc = argp_program_doc,
};
struct filetop_bpf *obj;
int err;
err = argp_parse(&argp, argc, argv, 0, NULL, NULL);
if (err)
return err;
libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
libbpf_set_print(libbpf_print_fn);
obj = filetop_bpf__open();
if (!obj) {
warn("failed to open BPF object\n");
return 1;
}
obj->rodata->target_pid = target_pid;
obj->rodata->regular_file_only = regular_file_only;
err = filetop_bpf__load(obj);
if (err) {
warn("failed to load BPF object: %d\n", err);
goto cleanup;
}
err = filetop_bpf__attach(obj);
if (err) {
warn("failed to attach BPF programs: %d\n", err);
goto cleanup;
}
if (signal(SIGINT, sig_int) == SIG_ERR) {
warn("can't set signal handler: %s\n", strerror(errno));
err = 1;
goto cleanup;
}
while (1) {
sleep(interval);
if (clear_screen) {
err = system("clear");
if (err)
goto cleanup;
}
err = print_stat(obj);
if (err)
goto cleanup;
count--;
if (exiting || !count)
goto cleanup;
}
cleanup:
filetop_bpf__destroy(obj);
return err != 0;
}