xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: notify offload JITs about optimizations

Browse Source 
Let offload JITs know when instructions are replaced and optimized
out, so they can update their state appropriately.  The optimizations
are best effort, if JIT returns an error from any callback verifier
will stop notifying it as state may now be out of sync, but the
verifier continues making progress.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Jakub Kicinski
2019-01-22 22:45:24 -08:00
committed by Alexei Starovoitov
parent 9e4c24e7ee
commit 08ca90afba
4 changed files with 53 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
kernel/bpf/offload.c
View File

@@ -173,6 +173,41 @@ int bpf_prog_offload_finalize(struct bpf_verifier_env *env)
return ret;
}
void
bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off,
struct bpf_insn *insn)
{
const struct bpf_prog_offload_ops *ops;
struct bpf_prog_offload *offload;
int ret = -EOPNOTSUPP;
down_read(&bpf_devs_lock);
offload = env->prog->aux->offload;
if (offload) {
ops = offload->offdev->ops;
if (!offload->opt_failed && ops->replace_insn)
ret = ops->replace_insn(env, off, insn);
offload->opt_failed |= ret;
}
up_read(&bpf_devs_lock);
}
void
bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
{
struct bpf_prog_offload *offload;
int ret = -EOPNOTSUPP;
down_read(&bpf_devs_lock);
offload = env->prog->aux->offload;
if (offload) {
if (!offload->opt_failed && offload->offdev->ops->remove_insns)
ret = offload->offdev->ops->remove_insns(env, off, cnt);
offload->opt_failed |= ret;
}
up_read(&bpf_devs_lock);
}
static void __bpf_prog_offload_destroy(struct bpf_prog *prog)
{
struct bpf_prog_offload *offload = prog->aux->offload;

6
kernel/bpf/verifier.c
View File

@@ -6558,6 +6558,9 @@ static int verifier_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
unsigned int orig_prog_len = env->prog->len;
int err;
if (bpf_prog_is_dev_bound(env->prog->aux))
bpf_prog_offload_remove_insns(env, off, cnt);
err = bpf_remove_insns(env->prog, off, cnt);
if (err)
return err;
@@ -6632,6 +6635,9 @@ static void opt_hard_wire_dead_code_branches(struct bpf_verifier_env *env)
else
continue;
if (bpf_prog_is_dev_bound(env->prog->aux))
bpf_prog_offload_replace_insn(env, i, &ja);
memcpy(insn, &ja, sizeof(ja));
}
}