From: Martin KaFai Lau <kafai@fb.com>
Date: Thu, 25 Mar 2021 01:51:30 +0000 (-0700)
Subject: bpf: Simplify freeing logic in linfo and jited_linfo
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e16301fbe183;p=linux.git
bpf: Simplify freeing logic in linfo and jited_linfo
This patch simplifies the linfo freeing logic by combining
"bpf_prog_free_jited_linfo()" and "bpf_prog_free_unused_jited_linfo()"
into the new "bpf_prog_jit_attempt_done()".
It is a prep work for the kernel function call support. In a later
patch, freeing the kernel function call descriptors will also
be done in the "bpf_prog_jit_attempt_done()".
"bpf_prog_free_linfo()" is removed since it is only called by
"__bpf_prog_put_noref()". The kvfree() are directly called
instead.
It also takes this chance to s/kcalloc/kvcalloc/ for the jited_linfo
allocation.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015130.1544323-1-kafai@fb.com
---
diff --git a/include/linux/filter.h b/include/linux/filter.h
index b2b85b2cad8e4..0d9c710eb0508 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -877,8 +877,7 @@ void bpf_prog_free_linfo(struct bpf_prog *prog);
void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
const u32 *insn_to_jit_off);
int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
-void bpf_prog_free_jited_linfo(struct bpf_prog *prog);
-void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog);
+void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 75244ecb2389f..a35eb3d7b1261 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -143,25 +143,22 @@ int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog)
if (!prog->aux->nr_linfo || !prog->jit_requested)
return 0;
- prog->aux->jited_linfo = kcalloc(prog->aux->nr_linfo,
- sizeof(*prog->aux->jited_linfo),
- GFP_KERNEL_ACCOUNT | __GFP_NOWARN);
+ prog->aux->jited_linfo = kvcalloc(prog->aux->nr_linfo,
+ sizeof(*prog->aux->jited_linfo),
+ GFP_KERNEL_ACCOUNT | __GFP_NOWARN);
if (!prog->aux->jited_linfo)
return -ENOMEM;
return 0;
}
-void bpf_prog_free_jited_linfo(struct bpf_prog *prog)
+void bpf_prog_jit_attempt_done(struct bpf_prog *prog)
{
- kfree(prog->aux->jited_linfo);
- prog->aux->jited_linfo = NULL;
-}
-
-void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog)
-{
- if (prog->aux->jited_linfo && !prog->aux->jited_linfo[0])
- bpf_prog_free_jited_linfo(prog);
+ if (prog->aux->jited_linfo &&
+ (!prog->jited || !prog->aux->jited_linfo[0])) {
+ kvfree(prog->aux->jited_linfo);
+ prog->aux->jited_linfo = NULL;
+ }
}
/* The jit engine is responsible to provide an array
@@ -217,12 +214,6 @@ void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
insn_to_jit_off[linfo[i].insn_off - insn_start - 1];
}
-void bpf_prog_free_linfo(struct bpf_prog *prog)
-{
- bpf_prog_free_jited_linfo(prog);
- kvfree(prog->aux->linfo);
-}
-
struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
gfp_t gfp_extra_flags)
{
@@ -1866,15 +1857,13 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
return fp;
fp = bpf_int_jit_compile(fp);
- if (!fp->jited) {
- bpf_prog_free_jited_linfo(fp);
+ bpf_prog_jit_attempt_done(fp);
#ifdef CONFIG_BPF_JIT_ALWAYS_ON
+ if (!fp->jited) {
*err = -ENOTSUPP;
return fp;
-#endif
- } else {
- bpf_prog_free_unused_jited_linfo(fp);
}
+#endif
} else {
*err = bpf_prog_offload_compile(fp);
if (*err)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 250503482cda2..eaf85bf51c5a7 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1694,7 +1694,8 @@ static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
{
bpf_prog_kallsyms_del_all(prog);
btf_put(prog->aux->btf);
- bpf_prog_free_linfo(prog);
+ kvfree(prog->aux->jited_linfo);
+ kvfree(prog->aux->linfo);
if (prog->aux->attach_btf)
btf_put(prog->aux->attach_btf);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 85f9f842d15c2..b7df3f06a2796 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -11741,7 +11741,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
prog->bpf_func = func[0]->bpf_func;
prog->aux->func = func;
prog->aux->func_cnt = env->subprog_cnt;
- bpf_prog_free_unused_jited_linfo(prog);
+ bpf_prog_jit_attempt_done(prog);
return 0;
out_free:
for (i = 0; i < env->subprog_cnt; i++) {
@@ -11764,7 +11764,7 @@ out_undo_insn:
insn->off = 0;
insn->imm = env->insn_aux_data[i].call_imm;
}
- bpf_prog_free_jited_linfo(prog);
+ bpf_prog_jit_attempt_done(prog);
return err;
}