From 9d8b612d88e81c2cf7dbc0d4a827da6ca0d848e0 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Tue, 8 Mar 2016 15:07:52 -0800 Subject: [PATCH] samples/bpf: add bpf map stress test this test calls bpf programs from different contexts: from inside of slub, from rcu, from pretty much everywhere, since it kprobes all spin_lock functions. It stresses the bpf hash and percpu map pre-allocation, deallocation logic and call_rcu mechanisms. User space part adding more stress by walking and deleting map elements. Note that due to nature bpf_load.c the earlier kprobe+bpf programs are already active while loader loads new programs, creates new kprobes and attaches them. Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- samples/bpf/Makefile | 4 +++ samples/bpf/spintest_kern.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ samples/bpf/spintest_user.c | 50 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 113 insertions(+) create mode 100644 samples/bpf/spintest_kern.c create mode 100644 samples/bpf/spintest_user.c diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index c4f8ae0..75a13e7 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -17,6 +17,7 @@ hostprogs-y += tracex6 hostprogs-y += trace_output hostprogs-y += lathist hostprogs-y += offwaketime +hostprogs-y += spintest test_verifier-objs := test_verifier.o libbpf.o test_maps-objs := test_maps.o libbpf.o @@ -34,6 +35,7 @@ tracex6-objs := bpf_load.o libbpf.o tracex6_user.o trace_output-objs := bpf_load.o libbpf.o trace_output_user.o lathist-objs := bpf_load.o libbpf.o lathist_user.o offwaketime-objs := bpf_load.o libbpf.o offwaketime_user.o +spintest-objs := bpf_load.o libbpf.o spintest_user.o # Tell kbuild to always build the programs always := $(hostprogs-y) @@ -50,6 +52,7 @@ always += trace_output_kern.o always += tcbpf1_kern.o always += lathist_kern.o always += offwaketime_kern.o +always += spintest_kern.o HOSTCFLAGS += -I$(objtree)/usr/include @@ -67,6 +70,7 @@ HOSTLOADLIBES_tracex6 += -lelf HOSTLOADLIBES_trace_output += -lelf -lrt HOSTLOADLIBES_lathist += -lelf HOSTLOADLIBES_offwaketime += -lelf +HOSTLOADLIBES_spintest += -lelf # point this to your LLVM backend with bpf support LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc diff --git a/samples/bpf/spintest_kern.c b/samples/bpf/spintest_kern.c new file mode 100644 index 0000000..ef8ac33 --- /dev/null +++ b/samples/bpf/spintest_kern.c @@ -0,0 +1,59 @@ +/* Copyright (c) 2016, Facebook + * + * 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. + */ +#include +#include +#include +#include +#include "bpf_helpers.h" + +struct bpf_map_def SEC("maps") my_map = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(long), + .value_size = sizeof(long), + .max_entries = 1024, +}; +struct bpf_map_def SEC("maps") my_map2 = { + .type = BPF_MAP_TYPE_PERCPU_HASH, + .key_size = sizeof(long), + .value_size = sizeof(long), + .max_entries = 1024, +}; + +#define PROG(foo) \ +int foo(struct pt_regs *ctx) \ +{ \ + long v = ctx->ip, *val; \ +\ + val = bpf_map_lookup_elem(&my_map, &v); \ + bpf_map_update_elem(&my_map, &v, &v, BPF_ANY); \ + bpf_map_update_elem(&my_map2, &v, &v, BPF_ANY); \ + bpf_map_delete_elem(&my_map2, &v); \ + return 0; \ +} + +/* add kprobes to all possible *spin* functions */ +SEC("kprobe/spin_unlock")PROG(p1) +SEC("kprobe/spin_lock")PROG(p2) +SEC("kprobe/mutex_spin_on_owner")PROG(p3) +SEC("kprobe/rwsem_spin_on_owner")PROG(p4) +SEC("kprobe/spin_unlock_irqrestore")PROG(p5) +SEC("kprobe/_raw_spin_unlock_irqrestore")PROG(p6) +SEC("kprobe/_raw_spin_unlock_bh")PROG(p7) +SEC("kprobe/_raw_spin_unlock")PROG(p8) +SEC("kprobe/_raw_spin_lock_irqsave")PROG(p9) +SEC("kprobe/_raw_spin_trylock_bh")PROG(p10) +SEC("kprobe/_raw_spin_lock_irq")PROG(p11) +SEC("kprobe/_raw_spin_trylock")PROG(p12) +SEC("kprobe/_raw_spin_lock")PROG(p13) +SEC("kprobe/_raw_spin_lock_bh")PROG(p14) +/* and to inner bpf helpers */ +SEC("kprobe/htab_map_update_elem")PROG(p15) +SEC("kprobe/__htab_percpu_map_update_elem")PROG(p16) +SEC("kprobe/htab_map_alloc")PROG(p17) + +char _license[] SEC("license") = "GPL"; +u32 _version SEC("version") = LINUX_VERSION_CODE; diff --git a/samples/bpf/spintest_user.c b/samples/bpf/spintest_user.c new file mode 100644 index 0000000..311ede5 --- /dev/null +++ b/samples/bpf/spintest_user.c @@ -0,0 +1,50 @@ +#include +#include +#include +#include +#include +#include +#include "libbpf.h" +#include "bpf_load.h" + +int main(int ac, char **argv) +{ + struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; + long key, next_key, value; + char filename[256]; + struct ksym *sym; + int i; + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + setrlimit(RLIMIT_MEMLOCK, &r); + + if (load_kallsyms()) { + printf("failed to process /proc/kallsyms\n"); + return 2; + } + + if (load_bpf_file(filename)) { + printf("%s", bpf_log_buf); + return 1; + } + + for (i = 0; i < 5; i++) { + key = 0; + printf("kprobing funcs:"); + while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0) { + bpf_lookup_elem(map_fd[0], &next_key, &value); + assert(next_key == value); + sym = ksym_search(value); + printf(" %s", sym->name); + key = next_key; + } + if (key) + printf("\n"); + key = 0; + while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0) + bpf_delete_elem(map_fd[0], &next_key); + sleep(1); + } + + return 0; +} -- 2.7.4