diff options
| author | Daniel T. Lee <danieltimlee@gmail.com> | 2023-08-18 11:01:19 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-08-22 00:39:10 +0200 |
| commit | 456d53554ca7e93d7e5e8eb7fe8c906d5ec6e7d0 (patch) | |
| tree | 4fd7df7b9f5d0c1d6627867b16b32ef113e5188a /samples | |
| parent | samples/bpf: refactor syscall tracing programs using BPF_KSYSCALL macro (diff) | |
| download | linux-456d53554ca7e93d7e5e8eb7fe8c906d5ec6e7d0.tar.xz linux-456d53554ca7e93d7e5e8eb7fe8c906d5ec6e7d0.zip | |
samples/bpf: simplify spintest with kprobe.multi
With the introduction of kprobe.multi, it is now possible to attach
multiple kprobes to a single BPF program without the need for multiple
definitions. Additionally, this method supports wildcard-based
matching, allowing for further simplification of BPF programs. In here,
an asterisk (*) wildcard is used to map to all symbols relevant to
spin_{lock|unlock}.
Furthermore, since kprobe.multi handles symbol matching, this commit
eliminates the need for the previous logic of reading the ksym table to
verify the existence of symbols.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Link: https://lore.kernel.org/r/20230818090119.477441-10-danieltimlee@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'samples')
| -rw-r--r-- | samples/bpf/spintest.bpf.c | 17 | ||||
| -rw-r--r-- | samples/bpf/spintest_user.c | 22 |
2 files changed, 10 insertions, 29 deletions
diff --git a/samples/bpf/spintest.bpf.c b/samples/bpf/spintest.bpf.c index 15740b16a3f7..cba5a9d50783 100644 --- a/samples/bpf/spintest.bpf.c +++ b/samples/bpf/spintest.bpf.c @@ -47,20 +47,9 @@ int foo(struct pt_regs *ctx) \ } /* 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) +SEC("kprobe.multi/spin_*lock*")PROG(spin_lock) +SEC("kprobe.multi/*_spin_on_owner")PROG(spin_on_owner) +SEC("kprobe.multi/_raw_spin_*lock*")PROG(raw_spin_lock) /* and to inner bpf helpers */ SEC("kprobe/htab_map_update_elem")PROG(p15) diff --git a/samples/bpf/spintest_user.c b/samples/bpf/spintest_user.c index 8c77600776fb..55971edb1088 100644 --- a/samples/bpf/spintest_user.c +++ b/samples/bpf/spintest_user.c @@ -9,13 +9,12 @@ int main(int ac, char **argv) { - char filename[256], symbol[256]; struct bpf_object *obj = NULL; struct bpf_link *links[20]; long key, next_key, value; struct bpf_program *prog; int map_fd, i, j = 0; - const char *section; + char filename[256]; struct ksym *sym; if (load_kallsyms()) { @@ -44,20 +43,13 @@ int main(int ac, char **argv) } bpf_object__for_each_program(prog, obj) { - section = bpf_program__section_name(prog); - if (sscanf(section, "kprobe/%s", symbol) != 1) - continue; - - /* Attach prog only when symbol exists */ - if (ksym_get_addr(symbol)) { - links[j] = bpf_program__attach(prog); - if (libbpf_get_error(links[j])) { - fprintf(stderr, "bpf_program__attach failed\n"); - links[j] = NULL; - goto cleanup; - } - j++; + links[j] = bpf_program__attach(prog); + if (libbpf_get_error(links[j])) { + fprintf(stderr, "bpf_program__attach failed\n"); + links[j] = NULL; + goto cleanup; } + j++; } for (i = 0; i < 5; i++) { |