[v8,28/35] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS

Message ID	170887441095.564249.13161375761711605227.stgit@devnote2 (mailing list archive)
State	Superseded
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 EF4C61C68C; Sun, 25 Feb 2024 15:20:16 +0000 (UTC) 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>, Sven Schnelle <svens@linux.ibm.com>, Alexei Starovoitov <ast@kernel.org>, Jiri Olsa <jolsa@kernel.org>, Arnaldo Carvalho de Melo <acme@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Alan Maguire <alan.maguire@oracle.com>, Mark Rutland <mark.rutland@arm.com>, Peter Zijlstra <peterz@infradead.org>, Thomas Gleixner <tglx@linutronix.de>, Guo Ren <guoren@kernel.org> Subject: [PATCH v8 28/35] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Date: Mon, 26 Feb 2024 00:20:11 +0900 Message-Id: <170887441095.564249.13161375761711605227.stgit@devnote2> In-Reply-To: <170887410337.564249.6360118840946697039.stgit@devnote2> References: <170887410337.564249.6360118840946697039.stgit@devnote2> User-Agent: StGit/0.19 Precedence: bulk MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit
Series	tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph \| expand [v8,00/35] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph [v8,01/35] tracing: Add a comment about ftrace_regs definition [v8,02/35] tracing: Rename ftrace_regs_return_value to ftrace_regs_get_return_value [v8,03/35] x86: tracing: Add ftrace_regs definition in the header [v8,04/35] function_graph: Convert ret_stack to a series of longs [v8,05/35] fgraph: Use BUILD_BUG_ON() to make sure we have structures divisible by long [v8,06/35] function_graph: Add an array structure that will allow multiple callbacks [v8,07/35] function_graph: Allow multiple users to attach to function graph [v8,08/35] function_graph: Remove logic around ftrace_graph_entry and return [v8,09/35] ftrace/function_graph: Pass fgraph_ops to function graph callbacks [v8,10/35] ftrace: Allow function_graph tracer to be enabled in instances [v8,11/35] ftrace: Allow ftrace startup flags exist without dynamic ftrace [v8,12/35] function_graph: Have the instances use their own ftrace_ops for filtering [v8,13/35] function_graph: Use a simple LRU for fgraph_array index number [v8,14/35] function_graph: Add "task variables" per task for fgraph_ops [v8,15/35] function_graph: Move set_graph_function tests to shadow stack global var [v8,16/35] function_graph: Move graph depth stored data to shadow stack global var [v8,17/35] function_graph: Move graph notrace bit to shadow stack global var [v8,18/35] function_graph: Implement fgraph_reserve_data() and fgraph_retrieve_data() [v8,19/35] function_graph: Add selftest for passing local variables [v8,20/35] ftrace: Add multiple fgraph storage selftest [v8,21/35] function_graph: Pass ftrace_regs to entryfunc [v8,22/35] function_graph: Replace fgraph_ret_regs with ftrace_regs [v8,23/35] function_graph: Pass ftrace_regs to retfunc [v8,24/35] fprobe: Use ftrace_regs in fprobe entry handler [v8,25/35] fprobe: Use ftrace_regs in fprobe exit handler [v8,26/35] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs [v8,27/35] tracing: Add ftrace_fill_perf_regs() for perf event [v8,28/35] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS [v8,29/35] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled [v8,30/35] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC [v8,31/35] fprobe: Rewrite fprobe on function-graph tracer [v8,32/35] tracing/fprobe: Remove nr_maxactive from fprobe [v8,33/35] selftests: ftrace: Remove obsolate maxactive syntax check [v8,34/35] selftests/ftrace: Add a test case for repeating register/unregister fprobe [v8,35/35] Documentation: probes: Update fprobe on function-graph tracer

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 56ee02afc15b..d895767dcb93 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -256,6 +256,23 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs) frame_pointer(&(fregs)->regs) #endif +#ifdef CONFIG_HAVE_REGS_AND_STACK_ACCESS_API +static __always_inline unsigned long +ftrace_regs_get_kernel_stack_nth(struct ftrace_regs *fregs, unsigned int nth) +{ + unsigned long *stackp; + + stackp = (unsigned long *)ftrace_regs_get_stack_pointer(fregs); + if (((unsigned long)(stackp + nth) & ~(THREAD_SIZE - 1)) == + ((unsigned long)stackp & ~(THREAD_SIZE - 1))) + return *(stackp + nth); + + return 0; +} +#else /* !CONFIG_HAVE_REGS_AND_STACK_ACCESS_API */ +#define ftrace_regs_get_kernel_stack_nth(fregs, nth) (0L) +#endif /* CONFIG_HAVE_REGS_AND_STACK_ACCESS_API */ + typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index d818ba3ff943..e2fc600f0ef2 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -680,7 +680,6 @@ 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/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 3982626c82e6..7d2a66135f83 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -132,7 +132,7 @@ static int process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, void *base) { - struct pt_regs *regs = rec; + struct ftrace_regs *fregs = rec; unsigned long val; int ret; @@ -140,17 +140,17 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, /* 1st stage: get value from context */ switch (code->op) { case FETCH_OP_STACK: - val = regs_get_kernel_stack_nth(regs, code->param); + val = ftrace_regs_get_kernel_stack_nth(fregs, code->param); break; case FETCH_OP_STACKP: - val = kernel_stack_pointer(regs); + val = ftrace_regs_get_stack_pointer(fregs); break; case FETCH_OP_RETVAL: - val = regs_return_value(regs); + val = ftrace_regs_get_return_value(fregs); break; #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API case FETCH_OP_ARG: - val = regs_get_kernel_argument(regs, code->param); + val = ftrace_regs_get_argument(fregs, code->param); break; #endif case FETCH_NOP_SYMBOL: /* Ignore a place holder */ @@ -170,7 +170,7 @@ NOKPROBE_SYMBOL(process_fetch_insn) /* function entry handler */ static nokprobe_inline void __fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs, + struct ftrace_regs *fregs, struct trace_event_file *trace_file) { struct fentry_trace_entry_head *entry; @@ -184,36 +184,36 @@ __fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, if (trace_trigger_soft_disabled(trace_file)) return; - dsize = __get_data_size(&tf->tp, regs); + dsize = __get_data_size(&tf->tp, fregs); entry = trace_event_buffer_reserve(&fbuffer, trace_file, sizeof(*entry) + tf->tp.size + dsize); if (!entry) return; - fbuffer.regs = regs; + fbuffer.regs = ftrace_get_regs(fregs); entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->ip = entry_ip; - store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, sizeof(*entry), dsize); trace_event_buffer_commit(&fbuffer); } static void fentry_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs) + struct ftrace_regs *fregs) { struct event_file_link *link; trace_probe_for_each_link_rcu(link, &tf->tp) - __fentry_trace_func(tf, entry_ip, regs, link->file); + __fentry_trace_func(tf, entry_ip, fregs, link->file); } NOKPROBE_SYMBOL(fentry_trace_func); /* Kretprobe handler */ static nokprobe_inline void __fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs, + unsigned long ret_ip, struct ftrace_regs *fregs, struct trace_event_file *trace_file) { struct fexit_trace_entry_head *entry; @@ -227,60 +227,63 @@ __fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, if (trace_trigger_soft_disabled(trace_file)) return; - dsize = __get_data_size(&tf->tp, regs); + dsize = __get_data_size(&tf->tp, fregs); entry = trace_event_buffer_reserve(&fbuffer, trace_file, sizeof(*entry) + tf->tp.size + dsize); if (!entry) return; - fbuffer.regs = regs; + fbuffer.regs = ftrace_get_regs(fregs); entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); entry->func = entry_ip; entry->ret_ip = ret_ip; - store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, sizeof(*entry), dsize); trace_event_buffer_commit(&fbuffer); } static void fexit_trace_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs) + unsigned long ret_ip, struct ftrace_regs *fregs) { struct event_file_link *link; trace_probe_for_each_link_rcu(link, &tf->tp) - __fexit_trace_func(tf, entry_ip, ret_ip, regs, link->file); + __fexit_trace_func(tf, entry_ip, ret_ip, fregs, link->file); } NOKPROBE_SYMBOL(fexit_trace_func); #ifdef CONFIG_PERF_EVENTS static int fentry_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, - struct pt_regs *regs) + struct ftrace_regs *fregs) { struct trace_event_call *call = trace_probe_event_call(&tf->tp); struct fentry_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; + struct pt_regs *regs; int rctx; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) return 0; - dsize = __get_data_size(&tf->tp, regs); + dsize = __get_data_size(&tf->tp, fregs); __size = sizeof(*entry) + tf->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_alloc(size, NULL, &rctx); + entry = perf_trace_buf_alloc(size, &regs, &rctx); if (!entry) return 0; + regs = ftrace_fill_perf_regs(fregs, regs); + entry->ip = entry_ip; memset(&entry[1], 0, dsize); - store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, sizeof(*entry), dsize); perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, head, NULL); return 0; @@ -289,30 +292,33 @@ NOKPROBE_SYMBOL(fentry_perf_func); static void fexit_perf_func(struct trace_fprobe *tf, unsigned long entry_ip, - unsigned long ret_ip, struct pt_regs *regs) + unsigned long ret_ip, struct ftrace_regs *fregs) { struct trace_event_call *call = trace_probe_event_call(&tf->tp); struct fexit_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; + struct pt_regs *regs; int rctx; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) return; - dsize = __get_data_size(&tf->tp, regs); + dsize = __get_data_size(&tf->tp, fregs); __size = sizeof(*entry) + tf->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); - entry = perf_trace_buf_alloc(size, NULL, &rctx); + entry = perf_trace_buf_alloc(size, &regs, &rctx); if (!entry) return; + regs = ftrace_fill_perf_regs(fregs, regs); + entry->func = entry_ip; entry->ret_ip = ret_ip; - store_trace_args(&entry[1], &tf->tp, regs, sizeof(*entry), dsize); + store_trace_args(&entry[1], &tf->tp, fregs, sizeof(*entry), dsize); perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, head, NULL); } @@ -324,17 +330,14 @@ static int fentry_dispatcher(struct fprobe *fp, unsigned long entry_ip, 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); + fentry_trace_func(tf, entry_ip, fregs); + #ifdef CONFIG_PERF_EVENTS if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) - ret = fentry_perf_func(tf, entry_ip, regs); + ret = fentry_perf_func(tf, entry_ip, fregs); #endif return ret; } @@ -345,16 +348,13 @@ static void fexit_dispatcher(struct fprobe *fp, unsigned long entry_ip, 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); + fexit_trace_func(tf, entry_ip, ret_ip, fregs); + #ifdef CONFIG_PERF_EVENTS if (trace_probe_test_flag(&tf->tp, TP_FLAG_PROFILE)) - fexit_perf_func(tf, entry_ip, ret_ip, regs); + fexit_perf_func(tf, entry_ip, ret_ip, fregs); #endif } NOKPROBE_SYMBOL(fexit_dispatcher); diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index 3935b347f874..05445a745a07 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -232,7 +232,7 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val, /* Sum up total data length for dynamic arrays (strings) */ static nokprobe_inline int -__get_data_size(struct trace_probe *tp, struct pt_regs *regs) +__get_data_size(struct trace_probe *tp, void *regs) { struct probe_arg *arg; int i, len, ret = 0;

[v8,28/35] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS

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