From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Florent Revest <revest@chromium.org>
Cc: linux-trace-kernel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
Martin KaFai Lau <martin.lau@linux.dev>,
bpf <bpf@vger.kernel.org>, Alexei Starovoitov <ast@kernel.org>,
Jiri Olsa <jolsa@kernel.org>,
Alan Maguire <alan.maguire@oracle.com>,
Mark Rutland <mark.rutland@arm.com>,
linux-arch@vger.kernel.org
Subject: [PATCH v20 04/19] fprobe: Use ftrace_regs in fprobe entry handler
Date: Fri, 6 Dec 2024 09:09:48 +0900 [thread overview]
Message-ID: <173344378792.50709.3102915644363061393.stgit@devnote2> (raw)
In-Reply-To: <173344373580.50709.5332611753907139634.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This allows fprobes to be available with CONFIG_DYNAMIC_FTRACE_WITH_ARGS
instead of CONFIG_DYNAMIC_FTRACE_WITH_REGS, then we can enable fprobe
on arm64.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Florent Revest <revest@chromium.org>
---
Changes in v6:
- Keep using SAVE_REGS flag to avoid breaking bpf kprobe-multi test.
---
include/linux/fprobe.h | 2 +-
kernel/trace/Kconfig | 3 ++-
kernel/trace/bpf_trace.c | 10 +++++++---
kernel/trace/fprobe.c | 3 ++-
kernel/trace/trace_fprobe.c | 6 +++++-
lib/test_fprobe.c | 4 ++--
samples/fprobe/fprobe_example.c | 2 +-
7 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h
index f39869588117..ca64ee5e45d2 100644
--- a/include/linux/fprobe.h
+++ b/include/linux/fprobe.h
@@ -10,7 +10,7 @@
struct fprobe;
typedef int (*fprobe_entry_cb)(struct fprobe *fp, unsigned long entry_ip,
- unsigned long ret_ip, struct pt_regs *regs,
+ unsigned long ret_ip, struct ftrace_regs *regs,
void *entry_data);
typedef void (*fprobe_exit_cb)(struct fprobe *fp, unsigned long entry_ip,
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index c5ab2a561272..f10ca86fbfad 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -297,7 +297,7 @@ config DYNAMIC_FTRACE_WITH_ARGS
config FPROBE
bool "Kernel Function Probe (fprobe)"
depends on FUNCTION_TRACER
- depends on DYNAMIC_FTRACE_WITH_REGS
+ depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS
depends on HAVE_RETHOOK
select RETHOOK
default n
@@ -682,6 +682,7 @@ config FPROBE_EVENTS
select TRACING
select PROBE_EVENTS
select DYNAMIC_EVENTS
+ depends on DYNAMIC_FTRACE_WITH_REGS
default y
help
This allows user to add tracing events on the function entry and
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 949a3870946c..ec83f1975e9e 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2550,7 +2550,7 @@ struct bpf_session_run_ctx {
void *data;
};
-#ifdef CONFIG_FPROBE
+#if defined(CONFIG_FPROBE) && defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS)
struct bpf_kprobe_multi_link {
struct bpf_link link;
struct fprobe fp;
@@ -2802,12 +2802,16 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
static int
kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip,
- unsigned long ret_ip, struct pt_regs *regs,
+ unsigned long ret_ip, struct ftrace_regs *fregs,
void *data)
{
+ struct pt_regs *regs = ftrace_get_regs(fregs);
struct bpf_kprobe_multi_link *link;
int err;
+ if (!regs)
+ return 0;
+
link = container_of(fp, struct bpf_kprobe_multi_link, fp);
err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false, data);
return is_kprobe_session(link->link.prog) ? err : 0;
@@ -3082,7 +3086,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
kvfree(cookies);
return err;
}
-#else /* !CONFIG_FPROBE */
+#else /* !CONFIG_FPROBE || !CONFIG_DYNAMIC_FTRACE_WITH_REGS */
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
return -EOPNOTSUPP;
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 9ff018245840..3d3789283873 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -46,7 +46,7 @@ static inline void __fprobe_handler(unsigned long ip, unsigned long parent_ip,
}
if (fp->entry_handler)
- ret = fp->entry_handler(fp, ip, parent_ip, ftrace_get_regs(fregs), entry_data);
+ ret = fp->entry_handler(fp, ip, parent_ip, fregs, entry_data);
/* If entry_handler returns !0, nmissed is not counted. */
if (rh) {
@@ -182,6 +182,7 @@ static void fprobe_init(struct fprobe *fp)
fp->ops.func = fprobe_kprobe_handler;
else
fp->ops.func = fprobe_handler;
+
fp->ops.flags |= FTRACE_OPS_FL_SAVE_REGS;
}
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
index c62d1629cffe..af54191a35b5 100644
--- a/kernel/trace/trace_fprobe.c
+++ b/kernel/trace/trace_fprobe.c
@@ -339,12 +339,16 @@ NOKPROBE_SYMBOL(fexit_perf_func);
#endif /* CONFIG_PERF_EVENTS */
static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip,
- unsigned long ret_ip, struct pt_regs *regs,
+ unsigned long ret_ip, struct ftrace_regs *fregs,
void *entry_data)
{
struct trace_fprobe *tf = container_of(fp, struct trace_fprobe, fp);
+ struct pt_regs *regs = ftrace_get_regs(fregs);
int ret = 0;
+ if (!regs)
+ return 0;
+
if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE))
fentry_trace_func(tf, entry_ip, regs);
#ifdef CONFIG_PERF_EVENTS
diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c
index 24de0e5ff859..ff607babba18 100644
--- a/lib/test_fprobe.c
+++ b/lib/test_fprobe.c
@@ -40,7 +40,7 @@ static noinline u32 fprobe_selftest_nest_target(u32 value, u32 (*nest)(u32))
static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip,
unsigned long ret_ip,
- struct pt_regs *regs, void *data)
+ struct ftrace_regs *fregs, void *data)
{
KUNIT_EXPECT_FALSE(current_test, preemptible());
/* This can be called on the fprobe_selftest_target and the fprobe_selftest_target2 */
@@ -81,7 +81,7 @@ static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip,
static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip,
unsigned long ret_ip,
- struct pt_regs *regs, void *data)
+ struct ftrace_regs *fregs, void *data)
{
KUNIT_EXPECT_FALSE(current_test, preemptible());
return 0;
diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c
index 0a50b05add96..c234afae52d6 100644
--- a/samples/fprobe/fprobe_example.c
+++ b/samples/fprobe/fprobe_example.c
@@ -50,7 +50,7 @@ static void show_backtrace(void)
static int sample_entry_handler(struct fprobe *fp, unsigned long ip,
unsigned long ret_ip,
- struct pt_regs *regs, void *data)
+ struct ftrace_regs *fregs, void *data)
{
if (use_trace)
/*
next prev parent reply other threads:[~2024-12-06 0:09 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-06 0:08 [PATCH v20 00/19] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu (Google)
2024-12-06 0:09 ` [PATCH v20 01/19] fgraph: Pass ftrace_regs to entryfunc Masami Hiramatsu (Google)
2024-12-06 0:09 ` [PATCH v20 02/19] fgraph: Replace fgraph_ret_regs with ftrace_regs Masami Hiramatsu (Google)
2024-12-06 0:09 ` [PATCH v20 03/19] fgraph: Pass ftrace_regs to retfunc Masami Hiramatsu (Google)
2024-12-06 0:09 ` Masami Hiramatsu (Google) [this message]
2024-12-06 0:09 ` [PATCH v20 05/19] fprobe: Use ftrace_regs in fprobe exit handler Masami Hiramatsu (Google)
2024-12-06 0:10 ` [PATCH v20 06/19] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Masami Hiramatsu (Google)
2024-12-06 0:10 ` [PATCH v20 07/19] tracing: Add ftrace_fill_perf_regs() for perf event Masami Hiramatsu (Google)
2024-12-06 0:10 ` [PATCH v20 08/19] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Masami Hiramatsu (Google)
2024-12-06 0:10 ` [PATCH v20 09/19] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Masami Hiramatsu (Google)
2024-12-06 0:11 ` [PATCH v20 10/19] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC Masami Hiramatsu (Google)
2024-12-06 0:11 ` [PATCH v20 11/19] s390/tracing: Enable HAVE_FTRACE_GRAPH_FUNC Masami Hiramatsu (Google)
2024-12-06 0:11 ` [PATCH v20 12/19] fprobe: Rewrite fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-12-06 0:11 ` [PATCH v20 13/19] fprobe: Add fprobe_header encoding feature Masami Hiramatsu (Google)
2024-12-06 0:11 ` [PATCH v20 14/19] tracing/fprobe: Remove nr_maxactive from fprobe Masami Hiramatsu (Google)
2024-12-06 0:12 ` [PATCH v20 15/19] selftests: ftrace: Remove obsolate maxactive syntax check Masami Hiramatsu (Google)
2024-12-06 0:12 ` [PATCH v20 16/19] selftests/ftrace: Add a test case for repeating register/unregister fprobe Masami Hiramatsu (Google)
2024-12-06 0:12 ` [PATCH v20 17/19] Documentation: probes: Update fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-12-06 0:12 ` [PATCH v20 18/19] ftrace: Add ftrace_get_symaddr to convert fentry_ip to symaddr Masami Hiramatsu (Google)
2024-12-06 0:12 ` [PATCH v20 19/19] bpf: Use ftrace_get_symaddr() in get_entry_ip() Masami Hiramatsu (Google)
2024-12-06 8:20 ` [PATCH v20 00/19] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu
2024-12-07 6:51 ` Masami Hiramatsu
2024-12-07 14:47 ` Steven Rostedt
2024-12-09 6:36 ` Masami Hiramatsu
2024-12-06 9:35 ` Heiko Carstens
2024-12-06 14:52 ` Steven Rostedt
2024-12-09 6:36 ` Masami Hiramatsu
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