From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Subject: [PATCH -tip -v11 10/11] tracing: Generate names for each kprobe event automatically Date: Thu, 09 Jul 2009 16:23:21 -0400 Message-ID: <20090709202321.13223.76914.stgit@localhost.localdomain> References: <20090709202220.13223.97114.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: systemtap, kvm, DLE, Masami Hiramatsu , Ananth N Mavinakayanahalli , Christoph Hellwig , Steven Rostedt , Ingo Molnar , Frederic Weisbecker , Tom Zanussi To: Ingo Molnar , Steven Rostedt , lkml Return-path: In-Reply-To: <20090709202220.13223.97114.stgit@localhost.localdomain> List-Unsubscribe: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org List-Id: kvm.vger.kernel.org Generate names for each kprobe event based on the probe point, and remove generic k*probe event types because there is no user of those types. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Christoph Hellwig Cc: Steven Rostedt Cc: Ingo Molnar Cc: Frederic Weisbecker Cc: Tom Zanussi --- Documentation/trace/kprobetrace.txt | 3 +- kernel/trace/trace_event_types.h | 18 ---------- kernel/trace/trace_kprobe.c | 62 +++++++++++++++++++---------------- 3 files changed, 35 insertions(+), 48 deletions(-) diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index b29a54b..437ad49 100644 --- a/Documentation/trace/kprobetrace.txt +++ b/Documentation/trace/kprobetrace.txt @@ -28,7 +28,8 @@ Synopsis of kprobe_events p[:EVENT] SYMBOL[+offs|-offs]|MEMADDR [FETCHARGS] : Set a probe r[:EVENT] SYMBOL[+0] [FETCHARGS] : Set a return probe - EVENT : Event name. + EVENT : Event name. If omitted, the event name is generated + based on SYMBOL+offs or MEMADDR. SYMBOL[+offs|-offs] : Symbol+offset where the probe is inserted. MEMADDR : Address where the probe is inserted. diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h index 186b598..e74f090 100644 --- a/kernel/trace/trace_event_types.h +++ b/kernel/trace/trace_event_types.h @@ -175,22 +175,4 @@ TRACE_EVENT_FORMAT(kmem_free, TRACE_KMEM_FREE, kmemtrace_free_entry, ignore, TP_RAW_FMT("type:%u call_site:%lx ptr:%p") ); -TRACE_EVENT_FORMAT(kprobe, TRACE_KPROBE, kprobe_trace_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, ip, ip) - TRACE_FIELD(int, nargs, nargs) - TRACE_FIELD_ZERO(unsigned long, args) - ), - TP_RAW_FMT("%08lx: args:0x%lx ...") -); - -TRACE_EVENT_FORMAT(kretprobe, TRACE_KRETPROBE, kretprobe_trace_entry, ignore, - TRACE_STRUCT( - TRACE_FIELD(unsigned long, func, func) - TRACE_FIELD(unsigned long, ret_ip, ret_ip) - TRACE_FIELD(int, nargs, nargs) - TRACE_FIELD_ZERO(unsigned long, args) - ), - TP_RAW_FMT("%08lx <- %08lx: args:0x%lx ...") -); #undef TRACE_SYSTEM diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 8754c7e..9c6ffcc 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -34,6 +34,7 @@ #define MAX_TRACE_ARGS 128 #define MAX_ARGSTR_LEN 63 +#define MAX_EVENT_NAME_LEN 64 /* currently, trace_kprobe only supports X86. */ @@ -265,11 +266,11 @@ static struct trace_probe *alloc_trace_probe(const char *symbol, if (!tp->symbol) goto error; } - if (event) { - tp->call.name = kstrdup(event, GFP_KERNEL); - if (!tp->call.name) - goto error; - } + if (!event) + goto error; + tp->call.name = kstrdup(event, GFP_KERNEL); + if (!tp->call.name) + goto error; INIT_LIST_HEAD(&tp->list); return tp; @@ -297,7 +298,7 @@ static struct trace_probe *find_probe_event(const char *event) { struct trace_probe *tp; list_for_each_entry(tp, &probe_list, list) - if (tp->call.name && !strcmp(tp->call.name, event)) + if (!strcmp(tp->call.name, event)) return tp; return NULL; } @@ -313,8 +314,7 @@ static void __unregister_trace_probe(struct trace_probe *tp) /* Unregister a trace_probe and probe_event: call with locking probe_lock */ static void unregister_trace_probe(struct trace_probe *tp) { - if (tp->call.name) - unregister_probe_event(tp); + unregister_probe_event(tp); __unregister_trace_probe(tp); list_del(&tp->list); } @@ -343,18 +343,16 @@ static int register_trace_probe(struct trace_probe *tp) goto end; } /* register as an event */ - if (tp->call.name) { - old_tp = find_probe_event(tp->call.name); - if (old_tp) { - /* delete old event */ - unregister_trace_probe(old_tp); - free_trace_probe(old_tp); - } - ret = register_probe_event(tp); - if (ret) { - pr_warning("Faild to register probe event(%d)\n", ret); - __unregister_trace_probe(tp); - } + old_tp = find_probe_event(tp->call.name); + if (old_tp) { + /* delete old event */ + unregister_trace_probe(old_tp); + free_trace_probe(old_tp); + } + ret = register_probe_event(tp); + if (ret) { + pr_warning("Faild to register probe event(%d)\n", ret); + __unregister_trace_probe(tp); } list_add_tail(&tp->list, &probe_list); end: @@ -557,7 +555,18 @@ static int create_trace_probe(int argc, char **argv) argc -= 2; argv += 2; /* setup a probe */ - tp = alloc_trace_probe(symbol, event, argc); + if (!event) { + /* Make a new event name */ + char buf[MAX_EVENT_NAME_LEN]; + if (symbol) + snprintf(buf, MAX_EVENT_NAME_LEN, "%c@%s%+ld", + is_return ? 'r' : 'p', symbol, offset); + else + snprintf(buf, MAX_EVENT_NAME_LEN, "%c@0x%p", + is_return ? 'r' : 'p', addr); + tp = alloc_trace_probe(symbol, buf, argc); + } else + tp = alloc_trace_probe(symbol, event, argc); if (IS_ERR(tp)) return PTR_ERR(tp); @@ -640,8 +649,7 @@ static int probes_seq_show(struct seq_file *m, void *v) return 0; seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p'); - if (tp->call.name) - seq_printf(m, ":%s", tp->call.name); + seq_printf(m, ":%s", tp->call.name); if (tp->symbol) seq_printf(m, " %s%+ld", probe_symbol(tp), probe_offset(tp)); @@ -762,9 +770,7 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) struct ring_buffer_event *event; int size, i, pc; unsigned long irq_flags; - struct ftrace_event_call *call = &event_kprobe; - if (&tp->call.name) - call = &tp->call; + struct ftrace_event_call *call = &tp->call; local_save_flags(irq_flags); pc = preempt_count(); @@ -796,9 +802,7 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, struct ring_buffer_event *event; int size, i, pc; unsigned long irq_flags; - struct ftrace_event_call *call = &event_kretprobe; - if (&tp->call.name) - call = &tp->call; + struct ftrace_event_call *call = &tp->call; local_save_flags(irq_flags); pc = preempt_count(); -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@redhat.com