blob: 2f3eb25941b7444fad44ef943c48833cbff852be [file] [log] [blame]
# mallocstacks Trace malloc() calls in a process and print the full
# stack trace for all callsites.
# For Linux, uses BCC, eBPF. Embedded C.
# This script is a basic example of the new Linux 4.6+ BPF_STACK_TRACE
# table API.
# Copyright 2016 GitHub, Inc.
# Licensed under the Apache License, Version 2.0 (the "License")
from __future__ import print_function
from bcc import BPF
from time import sleep
import sys
if len(sys.argv) < 2:
print("USAGE: mallocstacks PID")
pid = int(sys.argv[1])
# load BPF program
b = BPF(text="""
#include <uapi/linux/ptrace.h>
BPF_HASH(calls, int);
BPF_STACK_TRACE(stack_traces, 1024);
int alloc_enter(struct pt_regs *ctx, size_t size) {
int key = stack_traces.get_stackid(ctx,
if (key < 0)
return 0;
// could also use `calls.increment(key, size);`
u64 zero = 0, *val;
val = calls.lookup_or_init(&key, &zero);
(*val) += size;
return 0;
b.attach_uprobe(name="c", sym="malloc", fn_name="alloc_enter", pid=pid)
print("Attaching to malloc in pid %d, Ctrl+C to quit." % pid)
# sleep until Ctrl-C
except KeyboardInterrupt:
calls = b.get_table("calls")
stack_traces = b.get_table("stack_traces")
for k, v in reversed(sorted(calls.items(), key=lambda c: c[1].value)):
print("%d bytes allocated at:" % v.value)
for addr in stack_traces.walk(k.value):
print("\t%s" % b.sym(addr, pid, show_offset=True))