From: Jiri Olsa <jolsa@kernel.org>
To: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>
Cc: "Song Liu" <songliubraving@fb.com>,
netdev@vger.kernel.org, bpf@vger.kernel.org,
"Andrii Nakryiko" <andriin@fb.com>, "Yonghong Song" <yhs@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>,
"Arnaldo Carvalho de Melo" <acme@redhat.com>,
"Song Liu" <song@kernel.org>
Subject: [PATCH 04/15] bpf: Add name to struct bpf_ksym
Date: Thu, 12 Mar 2020 20:55:59 +0100 [thread overview]
Message-ID: <20200312195610.346362-5-jolsa@kernel.org> (raw)
In-Reply-To: <20200312195610.346362-1-jolsa@kernel.org>
Adding name to 'struct bpf_ksym' object to carry the name
of the symbol for bpf_prog, bpf_trampoline, bpf_dispatcher
objects.
The current benefit is that name is now generated only when
the symbol is added to the list, so we don't need to generate
it every time it's accessed.
The future benefit is that we will have all the bpf objects
symbols represented by struct bpf_ksym.
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 2 ++
include/linux/filter.h | 6 ------
kernel/bpf/core.c | 9 ++++++---
kernel/events/core.c | 9 ++++-----
4 files changed, 12 insertions(+), 14 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f5fa4c847451..e1cd64f2bf05 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -18,6 +18,7 @@
#include <linux/refcount.h>
#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/kallsyms.h>
struct bpf_verifier_env;
struct bpf_verifier_log;
@@ -474,6 +475,7 @@ void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start);
struct bpf_ksym {
unsigned long start;
unsigned long end;
+ char name[KSYM_NAME_LEN];
};
enum bpf_tramp_prog_type {
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 6249679275b3..9b5aa5c483cc 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1083,7 +1083,6 @@ bpf_address_lookup(unsigned long addr, unsigned long *size,
void bpf_prog_kallsyms_add(struct bpf_prog *fp);
void bpf_prog_kallsyms_del(struct bpf_prog *fp);
-void bpf_get_prog_name(const struct bpf_prog *prog, char *sym);
#else /* CONFIG_BPF_JIT */
@@ -1152,11 +1151,6 @@ static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
{
}
-static inline void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
-{
- sym[0] = '\0';
-}
-
#endif /* CONFIG_BPF_JIT */
void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index e2dd2d87c987..f86cb15d6f2e 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -535,8 +535,10 @@ bpf_prog_ksym_set_addr(struct bpf_prog *prog)
prog->aux->ksym.end = addr + hdr->pages * PAGE_SIZE;
}
-void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
+static void
+bpf_prog_ksym_set_name(struct bpf_prog *prog)
{
+ char *sym = prog->aux->ksym.name;
const char *end = sym + KSYM_NAME_LEN;
const struct btf_type *type;
const char *func_name;
@@ -643,6 +645,7 @@ void bpf_prog_kallsyms_add(struct bpf_prog *fp)
return;
bpf_prog_ksym_set_addr(fp);
+ bpf_prog_ksym_set_name(fp);
spin_lock_bh(&bpf_lock);
bpf_prog_ksym_node_add(fp->aux);
@@ -681,7 +684,7 @@ const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
unsigned long symbol_start = prog->aux->ksym.start;
unsigned long symbol_end = prog->aux->ksym.end;
- bpf_get_prog_name(prog, sym);
+ strncpy(sym, prog->aux->ksym.name, KSYM_NAME_LEN);
ret = sym;
if (size)
@@ -738,7 +741,7 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
if (it++ != symnum)
continue;
- bpf_get_prog_name(aux->prog, sym);
+ strncpy(sym, aux->ksym.name, KSYM_NAME_LEN);
*value = (unsigned long)aux->prog->bpf_func;
*type = BPF_SYM_ELF_TYPE;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index bbdfac0182f4..9b89ef176247 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8255,23 +8255,22 @@ static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog,
enum perf_bpf_event_type type)
{
bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD;
- char sym[KSYM_NAME_LEN];
int i;
if (prog->aux->func_cnt == 0) {
- bpf_get_prog_name(prog, sym);
perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF,
(u64)(unsigned long)prog->bpf_func,
- prog->jited_len, unregister, sym);
+ prog->jited_len, unregister,
+ prog->aux->ksym.name);
} else {
for (i = 0; i < prog->aux->func_cnt; i++) {
struct bpf_prog *subprog = prog->aux->func[i];
- bpf_get_prog_name(subprog, sym);
perf_event_ksymbol(
PERF_RECORD_KSYMBOL_TYPE_BPF,
(u64)(unsigned long)subprog->bpf_func,
- subprog->jited_len, unregister, sym);
+ subprog->jited_len, unregister,
+ prog->aux->ksym.name);
}
}
}
--
2.24.1
next prev parent reply other threads:[~2020-03-12 19:56 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-12 19:55 [PATCHv5 00/15] bpf: Add trampoline and dispatcher to /proc/kallsyms Jiri Olsa
2020-03-12 19:55 ` [PATCH 01/15] x86/mm: Rename is_kernel_text to __is_kernel_text Jiri Olsa
2020-03-12 19:55 ` [PATCH 02/15] bpf: Add bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER Jiri Olsa
2020-03-12 19:55 ` [PATCH 03/15] bpf: Add struct bpf_ksym Jiri Olsa
2020-03-12 19:55 ` Jiri Olsa [this message]
2020-03-12 19:56 ` [PATCH 05/15] bpf: Move lnode list node to " Jiri Olsa
2020-03-12 19:56 ` [PATCH 06/15] bpf: Move ksym_tnode to bpf_ksym Jiri Olsa
2020-03-12 19:56 ` [PATCH 07/15] bpf: Add bpf_ksym_find function Jiri Olsa
2020-03-12 19:56 ` [PATCH 08/15] bpf: Add prog flag to struct bpf_ksym object Jiri Olsa
2020-03-12 19:56 ` [PATCH 09/15] bpf: Add bpf_ksym_add/del functions Jiri Olsa
2020-03-12 19:56 ` [PATCH 10/15] bpf: Add trampolines to kallsyms Jiri Olsa
2020-03-12 19:56 ` [PATCH 11/15] bpf: Add dispatchers " Jiri Olsa
2020-03-12 19:56 ` [PATCH 12/15] bpf: Remove bpf_image tree Jiri Olsa
2020-03-12 19:56 ` [PATCH 13/15] perf tools: Synthesize bpf_trampoline/dispatcher ksymbol event Jiri Olsa
2020-04-06 12:54 ` Arnaldo Carvalho de Melo
2020-04-06 13:00 ` Jiri Olsa
2020-03-12 19:56 ` [PATCH 14/15] perf tools: Set ksymbol dso as loaded on arrival Jiri Olsa
2020-03-12 19:56 ` [PATCH 15/15] perf annotate: Add base support for bpf_image Jiri Olsa
2020-03-13 2:39 ` [PATCHv5 00/15] bpf: Add trampoline and dispatcher to /proc/kallsyms Alexei Starovoitov
2020-03-13 8:31 ` Jiri Olsa
2020-04-03 15:32 ` Arnaldo Carvalho de Melo
-- strict thread matches above, loose matches on Subject: below --
2020-03-02 14:31 [PATCHv4 " Jiri Olsa
2020-03-02 14:31 ` [PATCH 04/15] bpf: Add name to struct bpf_ksym 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=20200312195610.346362-5-jolsa@kernel.org \
--to=jolsa@kernel.org \
--cc=acme@redhat.com \
--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=song@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).