We no longer need ftrace_ops in each bpf_trampoline object, we can manage with just single ftrace_ops for all direct trampoline attachments.
Signed-off-by: Jiri Olsa <[email protected]> --- include/linux/bpf.h | 1 - kernel/bpf/trampoline.c | 34 ++++++++++------------------------ 2 files changed, 10 insertions(+), 25 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c14bde400d97..bad29fe38a12 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1257,7 +1257,6 @@ struct bpf_trampoline { struct hlist_node hlist_key; /* hlist for trampoline_ip_table */ struct hlist_node hlist_ip; - struct ftrace_ops *fops; /* serializes access to fields of this trampoline */ struct mutex mutex; refcount_t refcnt; diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 398c1a722d83..e6a0e7b20bb6 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -175,16 +175,6 @@ static struct bpf_trampoline *bpf_trampoline_lookup(u64 key, unsigned long ip) tr = kzalloc(sizeof(*tr), GFP_KERNEL); if (!tr) goto out; -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS - tr->fops = kzalloc(sizeof(struct ftrace_ops), GFP_KERNEL); - if (!tr->fops) { - kfree(tr); - tr = NULL; - goto out; - } - tr->fops->private = tr; - tr->fops->ops_func = bpf_tramp_ftrace_ops_func; -#endif tr->key = key; tr->ip = ip; @@ -202,13 +192,19 @@ static struct bpf_trampoline *bpf_trampoline_lookup(u64 key, unsigned long ip) return tr; } +struct ftrace_ops direct_ops = { +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + .ops_func = bpf_tramp_ftrace_ops_func, +#endif +}; + static int unregister_fentry(struct bpf_trampoline *tr, void *old_addr) { void *ip = tr->func.addr; int ret; if (tr->func.ftrace_managed) - ret = unregister_ftrace_direct(tr->fops, (unsigned long) ip, (long)old_addr, false); + ret = unregister_ftrace_direct(&direct_ops, (unsigned long) ip, (long)old_addr, false); else ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, old_addr, NULL); @@ -222,7 +218,7 @@ static int modify_fentry(struct bpf_trampoline *tr, void *old_addr, void *new_ad int ret; if (tr->func.ftrace_managed) { - ret = modify_ftrace_direct(tr->fops, (unsigned long) ip, (long)new_addr, lock_direct_mutex); + ret = modify_ftrace_direct(&direct_ops, (unsigned long) ip, (long)new_addr, lock_direct_mutex); } else { ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, old_addr, new_addr); } @@ -237,14 +233,11 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr) int ret; faddr = ftrace_location((unsigned long)ip); - if (faddr) { - if (!tr->fops) - return -ENOTSUPP; + if (faddr) tr->func.ftrace_managed = true; - } if (tr->func.ftrace_managed) { - ret = register_ftrace_direct(tr->fops, (unsigned long)ip, (long)new_addr); + ret = register_ftrace_direct(&direct_ops, (unsigned long)ip, (long)new_addr); } else { ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, NULL, new_addr); } @@ -502,9 +495,6 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut * BPF_TRAMP_F_SHARE_IPMODIFY is set, we can generate the * trampoline again, and retry register. */ - /* reset fops->func and fops->trampoline for re-register */ - tr->fops->func = NULL; - tr->fops->trampoline = 0; /* free im memory and reallocate later */ bpf_tramp_image_free(im); @@ -885,10 +875,6 @@ void bpf_trampoline_put(struct bpf_trampoline *tr) */ hlist_del(&tr->hlist_key); hlist_del(&tr->hlist_ip); - if (tr->fops) { - ftrace_free_filter(tr->fops); - kfree(tr->fops); - } kfree(tr); out: mutex_unlock(&trampoline_mutex); -- 2.50.1
