blob: f70f091487d65dd2f5ff52861bbd8b9a57e1dcd8 [file] [log] [blame]
#!/usr/bin/python
#
# bitehist.py Block I/O size histogram.
# For Linux, uses BCC, eBPF. See .c file.
#
# USAGE: bitesize
#
# Ctrl-C will print the partially gathered histogram then exit.
#
# Copyright (c) 2016 Allan McAleavy
# Licensed under the Apache License, Version 2.0 (the "License")
#
# 05-Feb-2016 Allan McAleavy ran pep8 against file
from bcc import BPF
from time import sleep
bpf_text = """
#include <uapi/linux/ptrace.h>
#include <linux/blkdev.h>
struct proc_key_t {
char name[TASK_COMM_LEN];
u64 slot;
};
struct val_t {
char name[TASK_COMM_LEN];
};
BPF_HISTOGRAM(dist, struct proc_key_t);
BPF_HASH(commbyreq, struct request *, struct val_t);
int trace_pid_start(struct pt_regs *ctx, struct request *req)
{
struct val_t val = {};
if (bpf_get_current_comm(&val.name, sizeof(val.name)) == 0) {
commbyreq.update(&req, &val);
}
return 0;
}
int do_count(struct pt_regs *ctx, struct request *req)
{
struct val_t *valp;
valp = commbyreq.lookup(&req);
if (valp == 0) {
return 0;
}
if (req->__data_len > 0) {
struct proc_key_t key = {.slot = bpf_log2l(req->__data_len / 1024)};
bpf_probe_read(&key.name, sizeof(key.name),valp->name);
dist.increment(key);
}
return 0;
}
"""
# load BPF program
b = BPF(text=bpf_text)
b.attach_kprobe(event="blk_account_io_start", fn_name="trace_pid_start")
b.attach_kprobe(event="blk_account_io_completion", fn_name="do_count")
print("Tracing... Hit Ctrl-C to end.")
# trace until Ctrl-C
dist = b.get_table("dist")
try:
sleep(99999999)
except KeyboardInterrupt:
dist.print_log2_hist("Kbytes", "Process Name",
section_print_fn=bytes.decode)