From patchwork Fri Dec 6 00:09:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13896101 X-Patchwork-Delegate: bpf@iogearbox.net 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 4B702BE46; Fri, 6 Dec 2024 00:10:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733443809; cv=none; b=jZ7tNRWhFc+P/mZML056sCfpK33gKF1aBs2aZ+ZL00WLfGCPXCLOAIBn30TLa7QcdKCLY1QM+XtoVI8GHwTyVZtsWjFEvXvLQk13An98CsYJoiDWSpxJygraLjx380u5u5jaCAJxk6rumKOohQIigxsra6g64lBrhIQmbjFFEqA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733443809; c=relaxed/simple; bh=iXpxzYtZSGT2TD0TwvAvJhEeBJZOzWR+9L5OxJZ7FS4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=d1Tyurma34DO+bDHcHWko+22VLz1Vcsjb6LeJecZ8+25I8wFXMoNAtGHDrNHF71PoY33G1PoBnrmjOrFIy2lqn2WmZ3aypo8lepPcQlLDebLqbfUGzdaZMwcK5UVx4QGK5BdFRWzthTqTtd6cyCE0vhbTDJ7ZjO1cHVy1YbfLTk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nTgewY0g; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nTgewY0g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 34F63C4CED1; Fri, 6 Dec 2024 00:10:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733443809; bh=iXpxzYtZSGT2TD0TwvAvJhEeBJZOzWR+9L5OxJZ7FS4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nTgewY0gSNh4iNs02FUmcr5hB659dsOKvF6jAxs0fxzWxMvp80f47EI24/NYxz1CF aIlzVac816lkn40tU50CGpfpXgKGaQkXmnLSAR7ZOUw6h48iB+aUqbJbRVqEnLuJhl A65jv95+WEHh1ctXhL6Dgc1TIwgh6fqTbek7cvgEThbQx3qKTHrBmOlve5BmNigvlf 8C6yrrTkG8WIBgScgBG3+pRvG/zywMS0YYp8ps1Jf2bPWerco5J6QOJp5RqVxpjUxz M89uYmM0qfLgwECpon8lTJsv22nw6wJoFYsQu8hvt1Y2uz0rgw+Z2uYAqWzIs53onm elpEAhJQn2Zkg== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Alexei Starovoitov , Jiri Olsa , Alan Maguire , Mark Rutland , linux-arch@vger.kernel.org, Huacai Chen , WANG Xuerui , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Mathieu Desnoyers , Song Liu , KP Singh , Matt Bobrowski , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Yonghong Song , John Fastabend , Stanislav Fomichev , Hao Luo , Andrew Morton Subject: [PATCH v20 05/19] fprobe: Use ftrace_regs in fprobe exit handler Date: Fri, 6 Dec 2024 09:09:58 +0900 Message-ID: <173344379888.50709.6405665526252062738.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <173344373580.50709.5332611753907139634.stgit@devnote2> References: <173344373580.50709.5332611753907139634.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Masami Hiramatsu (Google) Change the fprobe exit handler to use ftrace_regs structure instead of pt_regs. This also introduce HAVE_FTRACE_REGS_HAVING_PT_REGS which means the ftrace_regs is including the pt_regs so that ftrace_regs can provide pt_regs without memory allocation. Fprobe introduces a new dependency with that. Signed-off-by: Masami Hiramatsu (Google) Cc: Huacai Chen Cc: WANG Xuerui Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Sven Schnelle Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: x86@kernel.org Cc: "H. Peter Anvin" Cc: Steven Rostedt Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Song Liu Cc: Jiri Olsa Cc: KP Singh Cc: Matt Bobrowski Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Andrii Nakryiko Cc: Martin KaFai Lau Cc: Eduard Zingerman Cc: Yonghong Song Cc: John Fastabend Cc: Stanislav Fomichev Cc: Hao Luo Cc: Andrew Morton --- Changes in v16: - Rename HAVE_PT_REGS_TO_FTRACE_REGS_CAST to HAVE_FTRACE_REGS_HAVING_PT_REGS. Changes in v3: - Use ftrace_regs_get_return_value() Changes from previous series: NOTHING, just forward ported. --- arch/loongarch/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/x86/Kconfig | 1 + include/linux/fprobe.h | 2 +- include/linux/ftrace.h | 6 ++++++ kernel/trace/Kconfig | 7 +++++++ kernel/trace/bpf_trace.c | 6 +++++- kernel/trace/fprobe.c | 3 ++- kernel/trace/trace_fprobe.c | 6 +++++- lib/test_fprobe.c | 6 +++--- samples/fprobe/fprobe_example.c | 2 +- 11 files changed, 33 insertions(+), 8 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 49f5bfc00e5a..6396615ec035 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -128,6 +128,7 @@ config LOONGARCH select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_ARGS + select HAVE_FTRACE_REGS_HAVING_PT_REGS select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EBPF_JIT diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 102029e56cf0..d8eee56c10b6 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -183,6 +183,7 @@ config S390 select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_ARGS + select HAVE_FTRACE_REGS_HAVING_PT_REGS select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ff0d7e07c611..6cb420783ef3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -225,6 +225,7 @@ config X86 select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64 + select HAVE_FTRACE_REGS_HAVING_PT_REGS if X86_64 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_SAMPLE_FTRACE_DIRECT if X86_64 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if X86_64 diff --git a/include/linux/fprobe.h b/include/linux/fprobe.h index ca64ee5e45d2..ef609bcca0f9 100644 --- a/include/linux/fprobe.h +++ b/include/linux/fprobe.h @@ -14,7 +14,7 @@ typedef int (*fprobe_entry_cb)(struct fprobe *fp, unsigned long entry_ip, void *entry_data); typedef void (*fprobe_exit_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); /** diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 9a1e768e47da..bf8bb6c10553 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -176,6 +176,12 @@ static inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) #define ftrace_regs_set_instruction_pointer(fregs, ip) do { } while (0) #endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ +#ifdef CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS + +static_assert(sizeof(struct pt_regs) == ftrace_regs_size()); + +#endif /* CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS */ + static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs) { if (!fregs) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index f10ca86fbfad..7f8165f2049a 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -57,6 +57,12 @@ config HAVE_DYNAMIC_FTRACE_WITH_ARGS This allows for use of ftrace_regs_get_argument() and ftrace_regs_get_stack_pointer(). +config HAVE_FTRACE_REGS_HAVING_PT_REGS + bool + help + If this is set, ftrace_regs has pt_regs, thus it can convert to + pt_regs without allocating memory. + config HAVE_DYNAMIC_FTRACE_NO_PATCHABLE bool help @@ -298,6 +304,7 @@ config FPROBE bool "Kernel Function Probe (fprobe)" depends on FUNCTION_TRACER depends on DYNAMIC_FTRACE_WITH_REGS || DYNAMIC_FTRACE_WITH_ARGS + depends on HAVE_FTRACE_REGS_HAVING_PT_REGS || !HAVE_DYNAMIC_FTRACE_WITH_ARGS depends on HAVE_RETHOOK select RETHOOK default n diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index ec83f1975e9e..88aad3e3742c 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2819,10 +2819,14 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, static void kprobe_multi_link_exit_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 bpf_kprobe_multi_link *link; + struct pt_regs *regs = ftrace_get_regs(fregs); + + if (!regs) + return; link = container_of(fp, struct bpf_kprobe_multi_link, fp); kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true, data); diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 3d3789283873..90a3c8e2bbdf 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -124,6 +124,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, { struct fprobe *fp = (struct fprobe *)data; struct fprobe_rethook_node *fpr; + struct ftrace_regs *fregs = (struct ftrace_regs *)regs; int bit; if (!fp || fprobe_disabled(fp)) @@ -141,7 +142,7 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, return; } - fp->exit_handler(fp, fpr->entry_ip, ret_ip, regs, + fp->exit_handler(fp, fpr->entry_ip, ret_ip, fregs, fp->entry_data_size ? (void *)fpr->data : NULL); ftrace_test_recursion_unlock(bit); } diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index af54191a35b5..0a428a993ced 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -360,10 +360,14 @@ static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, NOKPROBE_SYMBOL(fentry_dispatcher); static void fexit_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); + + if (!regs) + return; if (trace_probe_test_flag(&tf->tp, TP_FLAG_TRACE)) fexit_trace_func(tf, entry_ip, ret_ip, regs, entry_data); diff --git a/lib/test_fprobe.c b/lib/test_fprobe.c index ff607babba18..271ce0caeec0 100644 --- a/lib/test_fprobe.c +++ b/lib/test_fprobe.c @@ -59,9 +59,9 @@ static notrace int fp_entry_handler(struct fprobe *fp, unsigned long ip, static notrace void fp_exit_handler(struct fprobe *fp, unsigned long ip, unsigned long ret_ip, - struct pt_regs *regs, void *data) + struct ftrace_regs *fregs, void *data) { - unsigned long ret = regs_return_value(regs); + unsigned long ret = ftrace_regs_get_return_value(fregs); KUNIT_EXPECT_FALSE(current_test, preemptible()); if (ip != target_ip) { @@ -89,7 +89,7 @@ static notrace int nest_entry_handler(struct fprobe *fp, unsigned long ip, static notrace void nest_exit_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()); KUNIT_EXPECT_EQ(current_test, ip, target_nest_ip); diff --git a/samples/fprobe/fprobe_example.c b/samples/fprobe/fprobe_example.c index c234afae52d6..bfe98ce826f3 100644 --- a/samples/fprobe/fprobe_example.c +++ b/samples/fprobe/fprobe_example.c @@ -67,7 +67,7 @@ static int sample_entry_handler(struct fprobe *fp, unsigned long ip, } static void sample_exit_handler(struct fprobe *fp, unsigned long ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *regs, void *data) { unsigned long rip = ret_ip;