From 4263565d491145b57621a761714f2ca6f1293a45 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 13 Aug 2009 16:35:26 -0400 Subject: [PATCH] tracing: Generate names for each kprobe event automatically MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Generate names for each kprobe event based on the probe point. (SYMBOL+offs or MEMADDR). Also remove generic k*probe event types because there is no user of those types. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Avi Kivity Cc: Andi Kleen Cc: Christoph Hellwig Cc: Frank Ch. Eigler Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Jason Baron Cc: Jim Keniston Cc: K.Prasad Cc: Lai Jiangshan Cc: Li Zefan Cc: Przemysław Pawełczyk Cc: Roland McGrath Cc: Sam Ravnborg Cc: Srikar Dronamraju Cc: Steven Rostedt Cc: Tom Zanussi Cc: Vegard Nossum LKML-Reference: <20090813203526.31965.56672.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker --- Documentation/trace/kprobetrace.txt | 3 +- kernel/trace/trace_event_types.h | 18 -------- kernel/trace/trace_kprobe.c | 64 +++++++++++++++-------------- 3 files changed, 35 insertions(+), 50 deletions(-) diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index c9c09b45038..5e59e854e71 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 186b598a1f1..e74f0906ab1 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 6d488efd16b..8aeb24cc295 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. */ @@ -280,11 +281,11 @@ 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; @@ -314,7 +315,7 @@ 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; } @@ -330,8 +331,7 @@ 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); } @@ -360,18 +360,16 @@ 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: @@ -580,7 +578,18 @@ 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); @@ -661,8 +670,7 @@ static int probes_seq_show(struct seq_file *m, void *v) char buf[MAX_ARGSTR_LEN + 1]; 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)); @@ -780,10 +788,7 @@ 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(); @@ -815,10 +820,7 @@ 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(); -- 2.39.2