[for-next,04/18] fprobe: Use ftrace_regs in fprobe entry handler

Message ID	20241227151401.253071329@goodmis.org (mailing list archive)
State	New
Delegated to:	BPF
Headers	show Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2BFC01F7096; Fri, 27 Dec 2024 15:13:00 +0000 (UTC) Message-ID: <20241227151401.253071329@goodmis.org> User-Agent: quilt/0.68 Date: Fri, 27 Dec 2024 10:13:39 -0500 From: Steven Rostedt <rostedt@goodmis.org> To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Andrew Morton <akpm@linux-foundation.org>, Alexei Starovoitov <alexei.starovoitov@gmail.com>, 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>, Florent Revest <revest@chromium.org> Subject: [for-next][PATCH 04/18] fprobe: Use ftrace_regs in fprobe entry handler References: <20241227151335.898746489@goodmis.org> Precedence: bulk MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8
Series	[for-next,01/18] fgraph: Pass ftrace_regs to entryfunc \| expand [for-next,01/18] fgraph: Pass ftrace_regs to entryfunc [for-next,02/18] fgraph: Replace fgraph_ret_regs with ftrace_regs [for-next,03/18] fgraph: Pass ftrace_regs to retfunc [for-next,04/18] fprobe: Use ftrace_regs in fprobe entry handler [for-next,05/18] fprobe: Use ftrace_regs in fprobe exit handler [for-next,06/18] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs [for-next,07/18] tracing: Add ftrace_fill_perf_regs() for perf event [for-next,08/18] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS [for-next,09/18] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled [for-next,10/18] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC [for-next,11/18] s390/tracing: Enable HAVE_FTRACE_GRAPH_FUNC [for-next,12/18] fprobe: Rewrite fprobe on function-graph tracer [for-next,13/18] fprobe: Add fprobe_header encoding feature [for-next,14/18] tracing/fprobe: Remove nr_maxactive from fprobe [for-next,15/18] selftests: ftrace: Remove obsolate maxactive syntax check [for-next,16/18] selftests/ftrace: Add a test case for repeating register/unregister fprobe [for-next,17/18] Documentation: probes: Update fprobe on function-graph tracer [for-next,18/18] ftrace: Add ftrace_get_symaddr to convert fentry_ip to symaddr

Context	Check	Description
netdev/tree_selection	success	Guessing tree name failed - patch did not apply
bpf/vmtest-bpf-PR	fail	merge-conflict

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 1b8db5aee9d3..7bb2e6ecd31f 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2561,7 +2561,7 @@ 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; @@ -2813,12 +2813,16 @@ 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; @@ -3093,7 +3097,7 @@ 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..0f254685e26a 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -217,12 +217,13 @@ NOKPROBE_SYMBOL(fentry_trace_func); /* function exit handler */ static int trace_fprobe_entry_handler(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); - if (tf->tp.entry_arg) + if (regs && tf->tp.entry_arg) store_trace_entry_data(entry_data, &tf->tp, regs); return 0; @@ -339,12 +340,16 @@ 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) /*

[for-next,04/18] fprobe: Use ftrace_regs in fprobe entry handler

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