From: Jiri Olsa <jolsa@kernel.org>
To: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org, bpf@vger.kernel.org,
"Andrii Nakryiko" <andriin@fb.com>, "Yonghong Song" <yhs@fb.com>,
"Song Liu" <songliubraving@fb.com>,
"Martin KaFai Lau" <kafai@fb.com>,
"Jakub Kicinski" <kuba@kernel.org>,
"David Miller" <davem@redhat.com>,
"Björn Töpel" <bjorn.topel@intel.com>,
"John Fastabend" <john.fastabend@gmail.com>,
"Jesper Dangaard Brouer" <hawk@kernel.org>
Subject: [PATCH 12/14] bpf: Add trampolines to kallsyms
Date: Sat, 8 Feb 2020 16:42:07 +0100 [thread overview]
Message-ID: <20200208154209.1797988-13-jolsa@kernel.org> (raw)
In-Reply-To: <20200208154209.1797988-1-jolsa@kernel.org>
Adding trampolines to kallsyms. It's displayed as
bpf_trampoline_<ID> [bpf]
where ID is the BTF id of the trampoline function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 2 ++
kernel/bpf/trampoline.c | 23 +++++++++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 7a4626c8e747..b91bac10d3ea 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -502,6 +502,7 @@ struct bpf_trampoline {
/* Executable image of trampoline */
void *image;
u64 selector;
+ struct bpf_ksym ksym;
};
#define BPF_DISPATCHER_MAX 48 /* Fits in 2048B */
@@ -573,6 +574,7 @@ struct bpf_image {
#define BPF_IMAGE_SIZE (PAGE_SIZE - sizeof(struct bpf_image))
bool is_bpf_image_address(unsigned long address);
void *bpf_image_alloc(void);
+void bpf_image_ksym_add(void *data, struct bpf_ksym *ksym);
/* Called only from code, so there's no need for stubs. */
void bpf_ksym_add(struct bpf_ksym *ksym);
void bpf_ksym_del(struct bpf_ksym *ksym);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 6b264a92064b..1ee29907cbe5 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -96,6 +96,15 @@ bool is_bpf_image_address(unsigned long addr)
return ret;
}
+void bpf_image_ksym_add(void *data, struct bpf_ksym *ksym)
+{
+ struct bpf_image *image = container_of(data, struct bpf_image, data);
+
+ ksym->start = (unsigned long) image;
+ ksym->end = ksym->start + PAGE_SIZE;
+ bpf_ksym_add(ksym);
+}
+
struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
{
struct bpf_trampoline *tr;
@@ -131,6 +140,7 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
for (i = 0; i < BPF_TRAMP_MAX; i++)
INIT_HLIST_HEAD(&tr->progs_hlist[i]);
tr->image = image;
+ INIT_LIST_HEAD_RCU(&tr->ksym.lnode);
out:
mutex_unlock(&trampoline_mutex);
return tr;
@@ -267,6 +277,15 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(enum bpf_attach_type t)
}
}
+static void bpf_trampoline_kallsyms_add(struct bpf_trampoline *tr)
+{
+ struct bpf_ksym *ksym = &tr->ksym;
+
+ snprintf(ksym->name, KSYM_NAME_LEN, "bpf_trampoline_%llu",
+ tr->key & ((u64) (1LU << 32) - 1));
+ bpf_image_ksym_add(tr->image, &tr->ksym);
+}
+
int bpf_trampoline_link_prog(struct bpf_prog *prog)
{
enum bpf_tramp_prog_type kind;
@@ -311,6 +330,8 @@ int bpf_trampoline_link_prog(struct bpf_prog *prog)
if (err) {
hlist_del(&prog->aux->tramp_hlist);
tr->progs_cnt[kind]--;
+ } else if (cnt == 0) {
+ bpf_trampoline_kallsyms_add(tr);
}
out:
mutex_unlock(&tr->mutex);
@@ -336,6 +357,8 @@ int bpf_trampoline_unlink_prog(struct bpf_prog *prog)
}
hlist_del(&prog->aux->tramp_hlist);
tr->progs_cnt[kind]--;
+ if (!(tr->progs_cnt[BPF_TRAMP_FENTRY] + tr->progs_cnt[BPF_TRAMP_FEXIT]))
+ bpf_ksym_del(&tr->ksym);
err = bpf_trampoline_update(prog->aux->trampoline);
out:
mutex_unlock(&tr->mutex);
--
2.24.1
next prev parent reply other threads:[~2020-02-08 15:43 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-08 15:41 [PATCH 00/14] bpf: Add trampoline and dispatcher to /proc/kallsyms Jiri Olsa
2020-02-08 15:41 ` [PATCH 01/14] x86/mm: Rename is_kernel_text to __is_kernel_text Jiri Olsa
2020-02-08 15:41 ` [PATCH 02/14] bpf: Add bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER Jiri Olsa
2020-02-08 15:41 ` [PATCH 03/14] bpf: Add struct bpf_ksym Jiri Olsa
2020-02-08 15:41 ` [PATCH 04/14] bpf: Add name to " Jiri Olsa
2020-02-08 15:42 ` [PATCH 05/14] bpf: Add lnode list node " Jiri Olsa
2020-02-08 15:42 ` [PATCH 06/14] bpf: Add bpf_kallsyms_tree tree Jiri Olsa
2020-02-11 18:21 ` Andrii Nakryiko
2020-02-12 10:49 ` Jiri Olsa
2020-02-08 15:42 ` [PATCH 07/14] bpf: Move bpf_tree add/del from bpf_prog_ksym_node_add/del Jiri Olsa
2020-02-08 15:42 ` [PATCH 08/14] bpf: Separate kallsyms add/del functions Jiri Olsa
2020-02-08 15:42 ` [PATCH 09/14] bpf: Add bpf_ksym_add/del functions Jiri Olsa
2020-02-08 15:42 ` [PATCH 10/14] bpf: Re-initialize lnode in bpf_ksym_del Jiri Olsa
2020-02-11 18:28 ` Andrii Nakryiko
2020-02-12 10:43 ` Jiri Olsa
2020-02-08 15:42 ` [PATCH 11/14] bpf: Rename bpf_tree to bpf_progs_tree Jiri Olsa
2020-02-08 15:42 ` Jiri Olsa [this message]
2020-02-11 18:51 ` [PATCH 12/14] bpf: Add trampolines to kallsyms Andrii Nakryiko
2020-02-12 11:10 ` Jiri Olsa
2020-02-12 16:33 ` Andrii Nakryiko
2020-02-12 22:58 ` Jiri Olsa
2020-02-12 23:02 ` Jiri Olsa
2020-02-08 15:42 ` [PATCH 13/14] bpf: Add dispatchers " Jiri Olsa
2020-02-11 19:03 ` Andrii Nakryiko
2020-02-12 10:52 ` Jiri Olsa
2020-02-08 15:42 ` [PATCH 14/14] bpf: Sort bpf kallsyms symbols Jiri Olsa
2020-02-11 19:12 ` Andrii Nakryiko
2020-02-10 15:51 ` [PATCH 00/14] bpf: Add trampoline and dispatcher to /proc/kallsyms Björn Töpel
2020-02-10 16:17 ` Jiri Olsa
2020-02-11 19:32 ` Arnaldo Carvalho de Melo
2020-02-12 11:13 ` Jiri Olsa
2020-02-12 13:31 ` Arnaldo Carvalho de Melo
2020-02-12 22:40 ` Jiri Olsa
2020-02-13 16:23 ` Jiri Olsa
2020-02-11 19:13 ` Arnaldo Carvalho de Melo
2020-02-12 10:46 ` Jiri Olsa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200208154209.1797988-13-jolsa@kernel.org \
--to=jolsa@kernel.org \
--cc=andriin@fb.com \
--cc=ast@kernel.org \
--cc=bjorn.topel@intel.com \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=davem@redhat.com \
--cc=hawk@kernel.org \
--cc=john.fastabend@gmail.com \
--cc=kafai@fb.com \
--cc=kuba@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=songliubraving@fb.com \
--cc=yhs@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).