2009-08-14 04:35:11 +08:00
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/*
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2009-11-04 08:12:47 +08:00
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* Kprobes-based tracing events
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2009-08-14 04:35:11 +08:00
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*
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* Created by Masami Hiramatsu <mhiramat@redhat.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/module.h>
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#include <linux/uaccess.h>
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2012-04-09 17:11:44 +08:00
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#include "trace_probe.h"
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2011-02-04 20:52:05 +08:00
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2012-04-09 17:11:44 +08:00
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#define KPROBE_EVENT_SYSTEM "kprobes"
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2010-07-06 02:54:45 +08:00
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2009-08-14 04:35:11 +08:00
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/**
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2009-11-04 08:12:47 +08:00
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* Kprobe event core functions
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2009-08-14 04:35:11 +08:00
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*/
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struct trace_probe {
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struct list_head list;
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2009-09-11 11:31:21 +08:00
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struct kretprobe rp; /* Use rp.kp for kprobe use */
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2009-08-14 04:35:42 +08:00
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unsigned long nhit;
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2009-09-15 04:49:20 +08:00
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unsigned int flags; /* For TP_FLAG_* */
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2009-08-14 04:35:11 +08:00
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const char *symbol; /* symbol name */
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2010-04-22 00:27:06 +08:00
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struct ftrace_event_class class;
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2009-08-14 04:35:11 +08:00
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struct ftrace_event_call call;
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tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
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ssize_t size; /* trace entry size */
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2009-08-14 04:35:18 +08:00
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unsigned int nr_args;
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2009-09-11 07:53:38 +08:00
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struct probe_arg args[];
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2009-08-14 04:35:11 +08:00
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};
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2009-08-14 04:35:18 +08:00
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#define SIZEOF_TRACE_PROBE(n) \
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(offsetof(struct trace_probe, args) + \
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2009-09-11 07:53:38 +08:00
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(sizeof(struct probe_arg) * (n)))
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2009-08-14 04:35:18 +08:00
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|
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tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
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2013-05-09 13:44:32 +08:00
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static __kprobes bool trace_probe_is_return(struct trace_probe *tp)
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2009-08-14 04:35:11 +08:00
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{
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2009-09-11 11:31:21 +08:00
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return tp->rp.handler != NULL;
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2009-08-14 04:35:11 +08:00
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}
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2011-06-27 15:26:36 +08:00
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static __kprobes const char *trace_probe_symbol(struct trace_probe *tp)
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2009-08-14 04:35:11 +08:00
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{
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return tp->symbol ? tp->symbol : "unknown";
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}
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2011-06-27 15:26:56 +08:00
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static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp)
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{
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return tp->rp.kp.offset;
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}
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static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp)
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{
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return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
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}
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static __kprobes bool trace_probe_is_registered(struct trace_probe *tp)
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{
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return !!(tp->flags & TP_FLAG_REGISTERED);
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}
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static __kprobes bool trace_probe_has_gone(struct trace_probe *tp)
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{
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return !!(kprobe_gone(&tp->rp.kp));
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}
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static __kprobes bool trace_probe_within_module(struct trace_probe *tp,
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struct module *mod)
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{
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int len = strlen(mod->name);
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const char *name = trace_probe_symbol(tp);
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return strncmp(mod->name, name, len) == 0 && name[len] == ':';
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}
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static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp)
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{
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return !!strchr(trace_probe_symbol(tp), ':');
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}
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2009-08-14 04:35:11 +08:00
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static int register_probe_event(struct trace_probe *tp);
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static void unregister_probe_event(struct trace_probe *tp);
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static DEFINE_MUTEX(probe_lock);
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static LIST_HEAD(probe_list);
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2009-09-15 04:49:20 +08:00
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static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
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static int kretprobe_dispatcher(struct kretprobe_instance *ri,
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struct pt_regs *regs);
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2009-09-11 11:31:21 +08:00
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/*
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* Allocate new trace_probe and initialize it (including kprobes).
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*/
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2009-09-11 07:53:53 +08:00
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static struct trace_probe *alloc_trace_probe(const char *group,
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const char *event,
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2009-09-11 11:31:21 +08:00
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void *addr,
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const char *symbol,
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unsigned long offs,
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2012-04-09 17:11:33 +08:00
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int nargs, bool is_return)
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2009-08-14 04:35:11 +08:00
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{
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struct trace_probe *tp;
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2009-12-17 06:24:08 +08:00
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int ret = -ENOMEM;
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2009-08-14 04:35:11 +08:00
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2009-08-14 04:35:18 +08:00
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tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);
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2009-08-14 04:35:11 +08:00
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if (!tp)
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2009-12-17 06:24:08 +08:00
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return ERR_PTR(ret);
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2009-08-14 04:35:11 +08:00
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if (symbol) {
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tp->symbol = kstrdup(symbol, GFP_KERNEL);
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if (!tp->symbol)
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goto error;
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2009-09-11 11:31:21 +08:00
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tp->rp.kp.symbol_name = tp->symbol;
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tp->rp.kp.offset = offs;
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} else
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tp->rp.kp.addr = addr;
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if (is_return)
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2009-09-15 04:49:20 +08:00
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tp->rp.handler = kretprobe_dispatcher;
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2009-09-11 11:31:21 +08:00
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else
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2009-09-15 04:49:20 +08:00
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tp->rp.kp.pre_handler = kprobe_dispatcher;
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2009-09-11 11:31:21 +08:00
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2010-08-27 19:39:12 +08:00
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if (!event || !is_good_name(event)) {
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2009-12-17 06:24:08 +08:00
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ret = -EINVAL;
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2009-08-14 04:35:26 +08:00
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goto error;
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2009-12-17 06:24:08 +08:00
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}
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2010-04-22 00:27:06 +08:00
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tp->call.class = &tp->class;
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2009-08-14 04:35:26 +08:00
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tp->call.name = kstrdup(event, GFP_KERNEL);
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if (!tp->call.name)
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goto error;
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2009-08-14 04:35:11 +08:00
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2010-08-27 19:39:12 +08:00
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if (!group || !is_good_name(group)) {
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2009-12-17 06:24:08 +08:00
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ret = -EINVAL;
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2009-09-11 07:53:53 +08:00
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goto error;
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2009-12-17 06:24:08 +08:00
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}
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2010-04-22 00:27:06 +08:00
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tp->class.system = kstrdup(group, GFP_KERNEL);
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if (!tp->class.system)
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2009-09-11 07:53:53 +08:00
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goto error;
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2009-08-14 04:35:11 +08:00
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INIT_LIST_HEAD(&tp->list);
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return tp;
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error:
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2009-09-11 07:53:53 +08:00
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kfree(tp->call.name);
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2009-08-14 04:35:11 +08:00
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kfree(tp->symbol);
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kfree(tp);
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2009-12-17 06:24:08 +08:00
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return ERR_PTR(ret);
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2009-08-14 04:35:11 +08:00
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}
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static void free_trace_probe(struct trace_probe *tp)
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{
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int i;
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for (i = 0; i < tp->nr_args; i++)
|
2012-04-09 17:11:44 +08:00
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traceprobe_free_probe_arg(&tp->args[i]);
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2009-08-14 04:35:11 +08:00
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2010-04-20 22:47:33 +08:00
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kfree(tp->call.class->system);
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2009-08-14 04:35:11 +08:00
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kfree(tp->call.name);
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kfree(tp->symbol);
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kfree(tp);
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}
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2011-06-27 15:26:36 +08:00
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static struct trace_probe *find_trace_probe(const char *event,
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2009-10-28 04:42:44 +08:00
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const char *group)
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2009-08-14 04:35:11 +08:00
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{
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struct trace_probe *tp;
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list_for_each_entry(tp, &probe_list, list)
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2009-10-28 04:42:44 +08:00
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if (strcmp(tp->call.name, event) == 0 &&
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2010-04-20 22:47:33 +08:00
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strcmp(tp->call.class->system, group) == 0)
|
2009-08-14 04:35:11 +08:00
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return tp;
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return NULL;
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}
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2011-06-27 15:26:44 +08:00
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/* Enable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
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static int enable_trace_probe(struct trace_probe *tp, int flag)
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{
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int ret = 0;
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tp->flags |= flag;
|
2011-06-27 15:26:56 +08:00
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if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) &&
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!trace_probe_has_gone(tp)) {
|
2011-06-27 15:26:44 +08:00
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if (trace_probe_is_return(tp))
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ret = enable_kretprobe(&tp->rp);
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else
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ret = enable_kprobe(&tp->rp.kp);
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}
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return ret;
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}
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/* Disable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
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static void disable_trace_probe(struct trace_probe *tp, int flag)
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{
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tp->flags &= ~flag;
|
2011-06-27 15:26:56 +08:00
|
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if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) {
|
2011-06-27 15:26:44 +08:00
|
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if (trace_probe_is_return(tp))
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disable_kretprobe(&tp->rp);
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else
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|
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disable_kprobe(&tp->rp.kp);
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|
|
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}
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}
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2011-06-27 15:26:56 +08:00
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/* Internal register function - just handle k*probes and flags */
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|
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static int __register_trace_probe(struct trace_probe *tp)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
2011-06-27 15:27:03 +08:00
|
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int i, ret;
|
2011-06-27 15:26:56 +08:00
|
|
|
|
|
|
|
if (trace_probe_is_registered(tp))
|
|
|
|
return -EINVAL;
|
|
|
|
|
2011-06-27 15:27:03 +08:00
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
2012-04-09 17:11:44 +08:00
|
|
|
traceprobe_update_arg(&tp->args[i]);
|
2011-06-27 15:27:03 +08:00
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
/* Set/clear disabled flag according to tp->flag */
|
|
|
|
if (trace_probe_is_enabled(tp))
|
|
|
|
tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
|
|
|
|
else
|
|
|
|
tp->rp.kp.flags |= KPROBE_FLAG_DISABLED;
|
|
|
|
|
2011-06-27 15:26:36 +08:00
|
|
|
if (trace_probe_is_return(tp))
|
2011-06-27 15:26:56 +08:00
|
|
|
ret = register_kretprobe(&tp->rp);
|
2009-08-14 04:35:11 +08:00
|
|
|
else
|
2011-06-27 15:26:56 +08:00
|
|
|
ret = register_kprobe(&tp->rp.kp);
|
|
|
|
|
|
|
|
if (ret == 0)
|
|
|
|
tp->flags |= TP_FLAG_REGISTERED;
|
|
|
|
else {
|
|
|
|
pr_warning("Could not insert probe at %s+%lu: %d\n",
|
|
|
|
trace_probe_symbol(tp), trace_probe_offset(tp), ret);
|
|
|
|
if (ret == -ENOENT && trace_probe_is_on_module(tp)) {
|
|
|
|
pr_warning("This probe might be able to register after"
|
|
|
|
"target module is loaded. Continue.\n");
|
|
|
|
ret = 0;
|
|
|
|
} else if (ret == -EILSEQ) {
|
|
|
|
pr_warning("Probing address(0x%p) is not an "
|
|
|
|
"instruction boundary.\n",
|
|
|
|
tp->rp.kp.addr);
|
|
|
|
ret = -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Internal unregister function - just handle k*probes and flags */
|
|
|
|
static void __unregister_trace_probe(struct trace_probe *tp)
|
|
|
|
{
|
|
|
|
if (trace_probe_is_registered(tp)) {
|
|
|
|
if (trace_probe_is_return(tp))
|
|
|
|
unregister_kretprobe(&tp->rp);
|
|
|
|
else
|
|
|
|
unregister_kprobe(&tp->rp.kp);
|
|
|
|
tp->flags &= ~TP_FLAG_REGISTERED;
|
|
|
|
/* Cleanup kprobe for reuse */
|
|
|
|
if (tp->rp.kp.symbol_name)
|
|
|
|
tp->rp.kp.addr = NULL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Unregister a trace_probe and probe_event: call with locking probe_lock */
|
2011-10-04 18:44:38 +08:00
|
|
|
static int unregister_trace_probe(struct trace_probe *tp)
|
2011-06-27 15:26:56 +08:00
|
|
|
{
|
2011-10-04 18:44:38 +08:00
|
|
|
/* Enabled event can not be unregistered */
|
|
|
|
if (trace_probe_is_enabled(tp))
|
|
|
|
return -EBUSY;
|
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
__unregister_trace_probe(tp);
|
2009-08-14 04:35:11 +08:00
|
|
|
list_del(&tp->list);
|
2009-09-15 04:48:56 +08:00
|
|
|
unregister_probe_event(tp);
|
2011-10-04 18:44:38 +08:00
|
|
|
|
|
|
|
return 0;
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Register a trace_probe and probe_event */
|
|
|
|
static int register_trace_probe(struct trace_probe *tp)
|
|
|
|
{
|
|
|
|
struct trace_probe *old_tp;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
mutex_lock(&probe_lock);
|
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
/* Delete old (same name) event if exist */
|
2011-06-27 15:26:36 +08:00
|
|
|
old_tp = find_trace_probe(tp->call.name, tp->call.class->system);
|
2009-09-15 04:48:56 +08:00
|
|
|
if (old_tp) {
|
2011-10-04 18:44:38 +08:00
|
|
|
ret = unregister_trace_probe(old_tp);
|
|
|
|
if (ret < 0)
|
|
|
|
goto end;
|
2009-09-15 04:48:56 +08:00
|
|
|
free_trace_probe(old_tp);
|
|
|
|
}
|
2011-06-27 15:26:56 +08:00
|
|
|
|
|
|
|
/* Register new event */
|
2009-09-15 04:48:56 +08:00
|
|
|
ret = register_probe_event(tp);
|
|
|
|
if (ret) {
|
2010-08-07 18:30:03 +08:00
|
|
|
pr_warning("Failed to register probe event(%d)\n", ret);
|
2009-09-15 04:48:56 +08:00
|
|
|
goto end;
|
|
|
|
}
|
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
/* Register k*probe */
|
|
|
|
ret = __register_trace_probe(tp);
|
|
|
|
if (ret < 0)
|
2009-09-15 04:48:56 +08:00
|
|
|
unregister_probe_event(tp);
|
2011-06-27 15:26:56 +08:00
|
|
|
else
|
2009-09-15 04:48:56 +08:00
|
|
|
list_add_tail(&tp->list, &probe_list);
|
2011-06-27 15:26:56 +08:00
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
end:
|
|
|
|
mutex_unlock(&probe_lock);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
/* Module notifier call back, checking event on the module */
|
|
|
|
static int trace_probe_module_callback(struct notifier_block *nb,
|
|
|
|
unsigned long val, void *data)
|
|
|
|
{
|
|
|
|
struct module *mod = data;
|
|
|
|
struct trace_probe *tp;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
if (val != MODULE_STATE_COMING)
|
|
|
|
return NOTIFY_DONE;
|
|
|
|
|
|
|
|
/* Update probes on coming module */
|
|
|
|
mutex_lock(&probe_lock);
|
|
|
|
list_for_each_entry(tp, &probe_list, list) {
|
|
|
|
if (trace_probe_within_module(tp, mod)) {
|
2011-10-04 18:44:38 +08:00
|
|
|
/* Don't need to check busy - this should have gone. */
|
2011-06-27 15:26:56 +08:00
|
|
|
__unregister_trace_probe(tp);
|
|
|
|
ret = __register_trace_probe(tp);
|
|
|
|
if (ret)
|
|
|
|
pr_warning("Failed to re-register probe %s on"
|
|
|
|
"%s: %d\n",
|
|
|
|
tp->call.name, mod->name, ret);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
mutex_unlock(&probe_lock);
|
|
|
|
|
|
|
|
return NOTIFY_DONE;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct notifier_block trace_probe_module_nb = {
|
|
|
|
.notifier_call = trace_probe_module_callback,
|
|
|
|
.priority = 1 /* Invoked after kprobe module callback */
|
|
|
|
};
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
static int create_trace_probe(int argc, char **argv)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Argument syntax:
|
2011-06-27 15:26:56 +08:00
|
|
|
* - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
|
|
|
|
* - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
|
2009-08-14 04:35:11 +08:00
|
|
|
* Fetch args:
|
2009-10-08 06:27:59 +08:00
|
|
|
* $retval : fetch return value
|
|
|
|
* $stack : fetch stack address
|
|
|
|
* $stackN : fetch Nth of stack (N:0-)
|
2009-08-14 04:35:11 +08:00
|
|
|
* @ADDR : fetch memory at ADDR (ADDR should be in kernel)
|
|
|
|
* @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
|
|
|
|
* %REG : fetch register REG
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
* Dereferencing memory fetch:
|
2009-08-14 04:35:11 +08:00
|
|
|
* +|-offs(ARG) : fetch memory at ARG +|- offs address.
|
2009-09-11 07:53:38 +08:00
|
|
|
* Alias name of args:
|
|
|
|
* NAME=FETCHARG : set NAME as alias of FETCHARG.
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
* Type of args:
|
|
|
|
* FETCHARG:TYPE : use TYPE instead of unsigned long.
|
2009-08-14 04:35:11 +08:00
|
|
|
*/
|
|
|
|
struct trace_probe *tp;
|
|
|
|
int i, ret = 0;
|
2012-04-09 17:11:33 +08:00
|
|
|
bool is_return = false, is_delete = false;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
char *symbol = NULL, *event = NULL, *group = NULL;
|
2010-08-27 19:39:12 +08:00
|
|
|
char *arg;
|
2009-09-11 07:53:14 +08:00
|
|
|
unsigned long offset = 0;
|
2009-08-14 04:35:11 +08:00
|
|
|
void *addr = NULL;
|
2009-09-11 11:31:21 +08:00
|
|
|
char buf[MAX_EVENT_NAME_LEN];
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-12-09 06:03:16 +08:00
|
|
|
/* argc must be >= 1 */
|
2009-08-14 04:35:11 +08:00
|
|
|
if (argv[0][0] == 'p')
|
2012-04-09 17:11:33 +08:00
|
|
|
is_return = false;
|
2009-08-14 04:35:11 +08:00
|
|
|
else if (argv[0][0] == 'r')
|
2012-04-09 17:11:33 +08:00
|
|
|
is_return = true;
|
2009-12-09 06:03:16 +08:00
|
|
|
else if (argv[0][0] == '-')
|
2012-04-09 17:11:33 +08:00
|
|
|
is_delete = true;
|
2009-10-17 08:07:28 +08:00
|
|
|
else {
|
2009-12-09 06:03:16 +08:00
|
|
|
pr_info("Probe definition must be started with 'p', 'r' or"
|
|
|
|
" '-'.\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return -EINVAL;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
if (argv[0][1] == ':') {
|
|
|
|
event = &argv[0][2];
|
2009-09-11 07:53:53 +08:00
|
|
|
if (strchr(event, '/')) {
|
|
|
|
group = event;
|
|
|
|
event = strchr(group, '/') + 1;
|
|
|
|
event[-1] = '\0';
|
|
|
|
if (strlen(group) == 0) {
|
2010-02-24 15:40:23 +08:00
|
|
|
pr_info("Group name is not specified\n");
|
2009-09-11 07:53:53 +08:00
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
if (strlen(event) == 0) {
|
2010-02-24 15:40:23 +08:00
|
|
|
pr_info("Event name is not specified\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
2009-12-09 06:03:16 +08:00
|
|
|
if (!group)
|
|
|
|
group = KPROBE_EVENT_SYSTEM;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-12-09 06:03:16 +08:00
|
|
|
if (is_delete) {
|
|
|
|
if (!event) {
|
|
|
|
pr_info("Delete command needs an event name.\n");
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
2010-06-30 16:45:48 +08:00
|
|
|
mutex_lock(&probe_lock);
|
2011-06-27 15:26:36 +08:00
|
|
|
tp = find_trace_probe(event, group);
|
2009-12-09 06:03:16 +08:00
|
|
|
if (!tp) {
|
2010-06-30 16:45:48 +08:00
|
|
|
mutex_unlock(&probe_lock);
|
2009-12-09 06:03:16 +08:00
|
|
|
pr_info("Event %s/%s doesn't exist.\n", group, event);
|
|
|
|
return -ENOENT;
|
|
|
|
}
|
|
|
|
/* delete an event */
|
2011-10-04 18:44:38 +08:00
|
|
|
ret = unregister_trace_probe(tp);
|
|
|
|
if (ret == 0)
|
|
|
|
free_trace_probe(tp);
|
2010-06-30 16:45:48 +08:00
|
|
|
mutex_unlock(&probe_lock);
|
2011-10-04 18:44:38 +08:00
|
|
|
return ret;
|
2009-12-09 06:03:16 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
if (argc < 2) {
|
|
|
|
pr_info("Probe point is not specified.\n");
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
if (isdigit(argv[1][0])) {
|
2009-10-17 08:07:28 +08:00
|
|
|
if (is_return) {
|
|
|
|
pr_info("Return probe point must be a symbol.\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return -EINVAL;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
/* an address specified */
|
2012-09-27 04:08:38 +08:00
|
|
|
ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
|
2009-10-17 08:07:28 +08:00
|
|
|
if (ret) {
|
|
|
|
pr_info("Failed to parse address.\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return ret;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
} else {
|
|
|
|
/* a symbol specified */
|
|
|
|
symbol = argv[1];
|
|
|
|
/* TODO: support .init module functions */
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_split_symbol_offset(symbol, &offset);
|
2009-10-17 08:07:28 +08:00
|
|
|
if (ret) {
|
|
|
|
pr_info("Failed to parse symbol.\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return ret;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
|
|
|
if (offset && is_return) {
|
|
|
|
pr_info("Return probe must be used without offset.\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return -EINVAL;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
2009-08-14 04:35:18 +08:00
|
|
|
argc -= 2; argv += 2;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
/* setup a probe */
|
2009-08-14 04:35:26 +08:00
|
|
|
if (!event) {
|
|
|
|
/* Make a new event name */
|
|
|
|
if (symbol)
|
2009-12-17 06:24:08 +08:00
|
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
|
2009-08-14 04:35:26 +08:00
|
|
|
is_return ? 'r' : 'p', symbol, offset);
|
|
|
|
else
|
2009-12-17 06:24:08 +08:00
|
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
|
2009-08-14 04:35:26 +08:00
|
|
|
is_return ? 'r' : 'p', addr);
|
2009-09-11 11:31:21 +08:00
|
|
|
event = buf;
|
|
|
|
}
|
2009-09-11 07:53:53 +08:00
|
|
|
tp = alloc_trace_probe(group, event, addr, symbol, offset, argc,
|
|
|
|
is_return);
|
2009-10-17 08:07:28 +08:00
|
|
|
if (IS_ERR(tp)) {
|
|
|
|
pr_info("Failed to allocate trace_probe.(%d)\n",
|
|
|
|
(int)PTR_ERR(tp));
|
2009-08-14 04:35:11 +08:00
|
|
|
return PTR_ERR(tp);
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
/* parse arguments */
|
2009-08-14 04:35:18 +08:00
|
|
|
ret = 0;
|
|
|
|
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
|
2010-08-27 19:38:46 +08:00
|
|
|
/* Increment count for freeing args in error case */
|
|
|
|
tp->nr_args++;
|
|
|
|
|
2009-09-11 07:53:38 +08:00
|
|
|
/* Parse argument name */
|
|
|
|
arg = strchr(argv[i], '=');
|
2010-08-27 19:39:06 +08:00
|
|
|
if (arg) {
|
2009-09-11 07:53:38 +08:00
|
|
|
*arg++ = '\0';
|
2010-08-27 19:39:06 +08:00
|
|
|
tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
|
|
|
|
} else {
|
2009-09-11 07:53:38 +08:00
|
|
|
arg = argv[i];
|
2010-08-27 19:39:06 +08:00
|
|
|
/* If argument name is omitted, set "argN" */
|
|
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
|
|
|
|
tp->args[i].name = kstrdup(buf, GFP_KERNEL);
|
|
|
|
}
|
2009-10-08 06:28:07 +08:00
|
|
|
|
2009-12-01 08:19:20 +08:00
|
|
|
if (!tp->args[i].name) {
|
2010-08-27 19:39:06 +08:00
|
|
|
pr_info("Failed to allocate argument[%d] name.\n", i);
|
2009-12-01 08:19:20 +08:00
|
|
|
ret = -ENOMEM;
|
2009-08-14 04:35:11 +08:00
|
|
|
goto error;
|
|
|
|
}
|
2010-08-27 19:39:12 +08:00
|
|
|
|
|
|
|
if (!is_good_name(tp->args[i].name)) {
|
|
|
|
pr_info("Invalid argument[%d] name: %s\n",
|
|
|
|
i, tp->args[i].name);
|
|
|
|
ret = -EINVAL;
|
|
|
|
goto error;
|
|
|
|
}
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
|
2012-04-09 17:11:44 +08:00
|
|
|
if (traceprobe_conflict_field_name(tp->args[i].name,
|
|
|
|
tp->args, i)) {
|
2010-08-27 19:39:06 +08:00
|
|
|
pr_info("Argument[%d] name '%s' conflicts with "
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
"another field.\n", i, argv[i]);
|
|
|
|
ret = -EINVAL;
|
|
|
|
goto error;
|
|
|
|
}
|
2009-12-01 08:19:20 +08:00
|
|
|
|
|
|
|
/* Parse fetch argument */
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i],
|
2012-04-11 18:30:43 +08:00
|
|
|
is_return, true);
|
2009-10-17 08:07:28 +08:00
|
|
|
if (ret) {
|
2010-08-27 19:39:06 +08:00
|
|
|
pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
|
2009-08-14 04:35:11 +08:00
|
|
|
goto error;
|
2009-10-17 08:07:28 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
ret = register_trace_probe(tp);
|
|
|
|
if (ret)
|
|
|
|
goto error;
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
error:
|
|
|
|
free_trace_probe(tp);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2011-10-04 18:44:38 +08:00
|
|
|
static int release_all_trace_probes(void)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
|
|
|
struct trace_probe *tp;
|
2011-10-04 18:44:38 +08:00
|
|
|
int ret = 0;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
mutex_lock(&probe_lock);
|
2011-10-04 18:44:38 +08:00
|
|
|
/* Ensure no probe is in use. */
|
|
|
|
list_for_each_entry(tp, &probe_list, list)
|
|
|
|
if (trace_probe_is_enabled(tp)) {
|
|
|
|
ret = -EBUSY;
|
|
|
|
goto end;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
/* TODO: Use batch unregistration */
|
|
|
|
while (!list_empty(&probe_list)) {
|
|
|
|
tp = list_entry(probe_list.next, struct trace_probe, list);
|
|
|
|
unregister_trace_probe(tp);
|
|
|
|
free_trace_probe(tp);
|
|
|
|
}
|
2011-10-04 18:44:38 +08:00
|
|
|
|
|
|
|
end:
|
2009-08-14 04:35:11 +08:00
|
|
|
mutex_unlock(&probe_lock);
|
2011-10-04 18:44:38 +08:00
|
|
|
|
|
|
|
return ret;
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Probes listing interfaces */
|
|
|
|
static void *probes_seq_start(struct seq_file *m, loff_t *pos)
|
|
|
|
{
|
|
|
|
mutex_lock(&probe_lock);
|
|
|
|
return seq_list_start(&probe_list, *pos);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos)
|
|
|
|
{
|
|
|
|
return seq_list_next(v, &probe_list, pos);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void probes_seq_stop(struct seq_file *m, void *v)
|
|
|
|
{
|
|
|
|
mutex_unlock(&probe_lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int probes_seq_show(struct seq_file *m, void *v)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = v;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
int i;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2011-06-27 15:26:36 +08:00
|
|
|
seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p');
|
2010-04-20 22:47:33 +08:00
|
|
|
seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-11-25 16:33:15 +08:00
|
|
|
if (!tp->symbol)
|
|
|
|
seq_printf(m, " 0x%p", tp->rp.kp.addr);
|
|
|
|
else if (tp->rp.kp.offset)
|
2011-06-27 15:26:36 +08:00
|
|
|
seq_printf(m, " %s+%u", trace_probe_symbol(tp),
|
|
|
|
tp->rp.kp.offset);
|
2009-08-14 04:35:11 +08:00
|
|
|
else
|
2011-06-27 15:26:36 +08:00
|
|
|
seq_printf(m, " %s", trace_probe_symbol(tp));
|
2009-08-14 04:35:11 +08:00
|
|
|
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
|
|
seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
|
2009-08-14 04:35:11 +08:00
|
|
|
seq_printf(m, "\n");
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct seq_operations probes_seq_op = {
|
|
|
|
.start = probes_seq_start,
|
|
|
|
.next = probes_seq_next,
|
|
|
|
.stop = probes_seq_stop,
|
|
|
|
.show = probes_seq_show
|
|
|
|
};
|
|
|
|
|
|
|
|
static int probes_open(struct inode *inode, struct file *file)
|
|
|
|
{
|
2011-10-04 18:44:38 +08:00
|
|
|
int ret;
|
|
|
|
|
|
|
|
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
|
|
|
|
ret = release_all_trace_probes();
|
|
|
|
if (ret < 0)
|
|
|
|
return ret;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
return seq_open(file, &probes_seq_op);
|
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t probes_write(struct file *file, const char __user *buffer,
|
|
|
|
size_t count, loff_t *ppos)
|
|
|
|
{
|
2012-04-09 17:11:44 +08:00
|
|
|
return traceprobe_probes_write(file, buffer, count, ppos,
|
|
|
|
create_trace_probe);
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations kprobe_events_ops = {
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.open = probes_open,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.release = seq_release,
|
|
|
|
.write = probes_write,
|
|
|
|
};
|
|
|
|
|
2009-08-14 04:35:42 +08:00
|
|
|
/* Probes profiling interfaces */
|
|
|
|
static int probes_profile_seq_show(struct seq_file *m, void *v)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = v;
|
|
|
|
|
|
|
|
seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit,
|
2009-09-11 11:31:21 +08:00
|
|
|
tp->rp.kp.nmissed);
|
2009-08-14 04:35:42 +08:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct seq_operations profile_seq_op = {
|
|
|
|
.start = probes_seq_start,
|
|
|
|
.next = probes_seq_next,
|
|
|
|
.stop = probes_seq_stop,
|
|
|
|
.show = probes_profile_seq_show
|
|
|
|
};
|
|
|
|
|
|
|
|
static int profile_open(struct inode *inode, struct file *file)
|
|
|
|
{
|
|
|
|
return seq_open(file, &profile_seq_op);
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct file_operations kprobe_profile_ops = {
|
|
|
|
.owner = THIS_MODULE,
|
|
|
|
.open = profile_open,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.release = seq_release,
|
|
|
|
};
|
|
|
|
|
2010-07-06 02:54:45 +08:00
|
|
|
/* Sum up total data length for dynamic arraies (strings) */
|
|
|
|
static __kprobes int __get_data_size(struct trace_probe *tp,
|
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
int i, ret = 0;
|
|
|
|
u32 len;
|
|
|
|
|
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
|
|
if (unlikely(tp->args[i].fetch_size.fn)) {
|
|
|
|
call_fetch(&tp->args[i].fetch_size, regs, &len);
|
|
|
|
ret += len;
|
|
|
|
}
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Store the value of each argument */
|
|
|
|
static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp,
|
|
|
|
struct pt_regs *regs,
|
|
|
|
u8 *data, int maxlen)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
u32 end = tp->size;
|
|
|
|
u32 *dl; /* Data (relative) location */
|
|
|
|
|
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
|
|
|
if (unlikely(tp->args[i].fetch_size.fn)) {
|
|
|
|
/*
|
|
|
|
* First, we set the relative location and
|
|
|
|
* maximum data length to *dl
|
|
|
|
*/
|
|
|
|
dl = (u32 *)(data + tp->args[i].offset);
|
|
|
|
*dl = make_data_rloc(maxlen, end - tp->args[i].offset);
|
|
|
|
/* Then try to fetch string or dynamic array data */
|
|
|
|
call_fetch(&tp->args[i].fetch, regs, dl);
|
|
|
|
/* Reduce maximum length */
|
|
|
|
end += get_rloc_len(*dl);
|
|
|
|
maxlen -= get_rloc_len(*dl);
|
|
|
|
/* Trick here, convert data_rloc to data_loc */
|
|
|
|
*dl = convert_rloc_to_loc(*dl,
|
|
|
|
ent_size + tp->args[i].offset);
|
|
|
|
} else
|
|
|
|
/* Just fetching data normally */
|
|
|
|
call_fetch(&tp->args[i].fetch, regs,
|
|
|
|
data + tp->args[i].offset);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
/* Kprobe handler */
|
2010-01-28 09:34:27 +08:00
|
|
|
static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
2009-09-11 11:31:21 +08:00
|
|
|
struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kprobe_trace_entry_head *entry;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct ring_buffer_event *event;
|
2009-09-11 07:09:23 +08:00
|
|
|
struct ring_buffer *buffer;
|
2010-07-06 02:54:45 +08:00
|
|
|
int size, dsize, pc;
|
2009-08-14 04:35:11 +08:00
|
|
|
unsigned long irq_flags;
|
2009-08-14 04:35:26 +08:00
|
|
|
struct ftrace_event_call *call = &tp->call;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
local_save_flags(irq_flags);
|
|
|
|
pc = preempt_count();
|
|
|
|
|
2010-07-06 02:54:45 +08:00
|
|
|
dsize = __get_data_size(tp, regs);
|
|
|
|
size = sizeof(*entry) + tp->size + dsize;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2010-04-23 22:38:03 +08:00
|
|
|
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
|
|
|
|
size, irq_flags, pc);
|
2009-08-14 04:35:11 +08:00
|
|
|
if (!event)
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
|
|
entry->ip = (unsigned long)kp->addr;
|
2010-07-06 02:54:45 +08:00
|
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-09-11 07:09:23 +08:00
|
|
|
if (!filter_current_check_discard(buffer, call, entry, event))
|
2012-11-02 08:54:21 +08:00
|
|
|
trace_buffer_unlock_commit_regs(buffer, event,
|
|
|
|
irq_flags, pc, regs);
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Kretprobe handler */
|
2010-01-28 09:34:27 +08:00
|
|
|
static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
|
2009-08-14 04:35:11 +08:00
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kretprobe_trace_entry_head *entry;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct ring_buffer_event *event;
|
2009-09-11 07:09:23 +08:00
|
|
|
struct ring_buffer *buffer;
|
2010-07-06 02:54:45 +08:00
|
|
|
int size, pc, dsize;
|
2009-08-14 04:35:11 +08:00
|
|
|
unsigned long irq_flags;
|
2009-08-14 04:35:26 +08:00
|
|
|
struct ftrace_event_call *call = &tp->call;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
local_save_flags(irq_flags);
|
|
|
|
pc = preempt_count();
|
|
|
|
|
2010-07-06 02:54:45 +08:00
|
|
|
dsize = __get_data_size(tp, regs);
|
|
|
|
size = sizeof(*entry) + tp->size + dsize;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2010-04-23 22:38:03 +08:00
|
|
|
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
|
|
|
|
size, irq_flags, pc);
|
2009-08-14 04:35:11 +08:00
|
|
|
if (!event)
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
entry = ring_buffer_event_data(event);
|
2009-09-11 11:31:21 +08:00
|
|
|
entry->func = (unsigned long)tp->rp.kp.addr;
|
2009-08-14 04:35:11 +08:00
|
|
|
entry->ret_ip = (unsigned long)ri->ret_addr;
|
2010-07-06 02:54:45 +08:00
|
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-09-11 07:09:23 +08:00
|
|
|
if (!filter_current_check_discard(buffer, call, entry, event))
|
2012-11-02 08:54:21 +08:00
|
|
|
trace_buffer_unlock_commit_regs(buffer, event,
|
|
|
|
irq_flags, pc, regs);
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Event entry printers */
|
|
|
|
enum print_line_t
|
2010-04-23 06:46:14 +08:00
|
|
|
print_kprobe_event(struct trace_iterator *iter, int flags,
|
|
|
|
struct trace_event *event)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kprobe_trace_entry_head *field;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct trace_seq *s = &iter->seq;
|
2009-09-11 07:53:38 +08:00
|
|
|
struct trace_probe *tp;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
u8 *data;
|
2009-08-14 04:35:11 +08:00
|
|
|
int i;
|
|
|
|
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
field = (struct kprobe_trace_entry_head *)iter->ent;
|
2010-04-23 22:00:22 +08:00
|
|
|
tp = container_of(event, struct trace_probe, call.event);
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-09-11 07:53:45 +08:00
|
|
|
if (!trace_seq_printf(s, "%s: (", tp->call.name))
|
|
|
|
goto partial;
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
|
|
|
|
goto partial;
|
|
|
|
|
2009-09-11 07:53:45 +08:00
|
|
|
if (!trace_seq_puts(s, ")"))
|
2009-08-14 04:35:11 +08:00
|
|
|
goto partial;
|
|
|
|
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
data = (u8 *)&field[1];
|
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
|
|
if (!tp->args[i].type->print(s, tp->args[i].name,
|
2010-07-06 02:54:45 +08:00
|
|
|
data + tp->args[i].offset, field))
|
2009-08-14 04:35:11 +08:00
|
|
|
goto partial;
|
|
|
|
|
|
|
|
if (!trace_seq_puts(s, "\n"))
|
|
|
|
goto partial;
|
|
|
|
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
|
|
partial:
|
|
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
}
|
|
|
|
|
|
|
|
enum print_line_t
|
2010-04-23 06:46:14 +08:00
|
|
|
print_kretprobe_event(struct trace_iterator *iter, int flags,
|
|
|
|
struct trace_event *event)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kretprobe_trace_entry_head *field;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct trace_seq *s = &iter->seq;
|
2009-09-11 07:53:38 +08:00
|
|
|
struct trace_probe *tp;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
u8 *data;
|
2009-08-14 04:35:11 +08:00
|
|
|
int i;
|
|
|
|
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
field = (struct kretprobe_trace_entry_head *)iter->ent;
|
2010-04-23 22:00:22 +08:00
|
|
|
tp = container_of(event, struct trace_probe, call.event);
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2009-09-11 07:53:45 +08:00
|
|
|
if (!trace_seq_printf(s, "%s: (", tp->call.name))
|
|
|
|
goto partial;
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
|
|
|
|
goto partial;
|
|
|
|
|
|
|
|
if (!trace_seq_puts(s, " <- "))
|
|
|
|
goto partial;
|
|
|
|
|
|
|
|
if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
|
|
|
|
goto partial;
|
|
|
|
|
2009-09-11 07:53:45 +08:00
|
|
|
if (!trace_seq_puts(s, ")"))
|
2009-08-14 04:35:11 +08:00
|
|
|
goto partial;
|
|
|
|
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
data = (u8 *)&field[1];
|
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
|
|
if (!tp->args[i].type->print(s, tp->args[i].name,
|
2010-07-06 02:54:45 +08:00
|
|
|
data + tp->args[i].offset, field))
|
2009-08-14 04:35:11 +08:00
|
|
|
goto partial;
|
|
|
|
|
|
|
|
if (!trace_seq_puts(s, "\n"))
|
|
|
|
goto partial;
|
|
|
|
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
|
|
partial:
|
|
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
|
|
|
|
{
|
|
|
|
int ret, i;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kprobe_trace_entry_head field;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct trace_probe *tp = (struct trace_probe *)event_call->data;
|
|
|
|
|
2009-10-08 06:28:07 +08:00
|
|
|
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
|
2009-09-11 07:53:38 +08:00
|
|
|
/* Set argument names as fields */
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
2010-07-06 02:54:45 +08:00
|
|
|
ret = trace_define_field(event_call, tp->args[i].type->fmttype,
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
tp->args[i].name,
|
|
|
|
sizeof(field) + tp->args[i].offset,
|
|
|
|
tp->args[i].type->size,
|
|
|
|
tp->args[i].type->is_signed,
|
|
|
|
FILTER_OTHER);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
|
|
|
|
{
|
|
|
|
int ret, i;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kretprobe_trace_entry_head field;
|
2009-08-14 04:35:11 +08:00
|
|
|
struct trace_probe *tp = (struct trace_probe *)event_call->data;
|
|
|
|
|
2009-10-08 06:28:07 +08:00
|
|
|
DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
|
|
|
|
DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
|
2009-09-11 07:53:38 +08:00
|
|
|
/* Set argument names as fields */
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
2010-07-06 02:54:45 +08:00
|
|
|
ret = trace_define_field(event_call, tp->args[i].type->fmttype,
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
tp->args[i].name,
|
|
|
|
sizeof(field) + tp->args[i].offset,
|
|
|
|
tp->args[i].type->size,
|
|
|
|
tp->args[i].type->is_signed,
|
|
|
|
FILTER_OTHER);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2009-12-15 15:39:49 +08:00
|
|
|
static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
int pos = 0;
|
|
|
|
|
|
|
|
const char *fmt, *arg;
|
|
|
|
|
2011-06-27 15:26:36 +08:00
|
|
|
if (!trace_probe_is_return(tp)) {
|
2009-12-15 15:39:49 +08:00
|
|
|
fmt = "(%lx)";
|
|
|
|
arg = "REC->" FIELD_STRING_IP;
|
|
|
|
} else {
|
|
|
|
fmt = "(%lx <- %lx)";
|
|
|
|
arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* When len=0, we just calculate the needed length */
|
|
|
|
#define LEN_OR_ZERO (len ? len - pos : 0)
|
|
|
|
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
|
|
|
|
|
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
|
|
|
|
tp->args[i].name, tp->args[i].type->fmt);
|
2009-12-15 15:39:49 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
|
|
|
|
|
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
2010-07-06 02:54:45 +08:00
|
|
|
if (strcmp(tp->args[i].type->name, "string") == 0)
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO,
|
|
|
|
", __get_str(%s)",
|
|
|
|
tp->args[i].name);
|
|
|
|
else
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
|
|
|
|
tp->args[i].name);
|
2009-12-15 15:39:49 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
#undef LEN_OR_ZERO
|
|
|
|
|
|
|
|
/* return the length of print_fmt */
|
|
|
|
return pos;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int set_print_fmt(struct trace_probe *tp)
|
|
|
|
{
|
|
|
|
int len;
|
|
|
|
char *print_fmt;
|
|
|
|
|
|
|
|
/* First: called with 0 length to calculate the needed length */
|
|
|
|
len = __set_print_fmt(tp, NULL, 0);
|
|
|
|
print_fmt = kmalloc(len + 1, GFP_KERNEL);
|
|
|
|
if (!print_fmt)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
/* Second: actually write the @print_fmt */
|
|
|
|
__set_print_fmt(tp, print_fmt, len + 1);
|
|
|
|
tp->call.print_fmt = print_fmt;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2009-12-21 14:27:35 +08:00
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
2009-09-11 07:53:30 +08:00
|
|
|
|
|
|
|
/* Kprobe profile handler */
|
2010-03-05 12:35:37 +08:00
|
|
|
static __kprobes void kprobe_perf_func(struct kprobe *kp,
|
2009-09-11 07:53:30 +08:00
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
|
|
|
|
struct ftrace_event_call *call = &tp->call;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kprobe_trace_entry_head *entry;
|
2010-05-19 20:02:22 +08:00
|
|
|
struct hlist_head *head;
|
2010-07-06 02:54:45 +08:00
|
|
|
int size, __size, dsize;
|
2009-11-23 18:37:29 +08:00
|
|
|
int rctx;
|
2009-09-11 07:53:30 +08:00
|
|
|
|
2010-07-06 02:54:45 +08:00
|
|
|
dsize = __get_data_size(tp, regs);
|
|
|
|
__size = sizeof(*entry) + tp->size + dsize;
|
2009-09-15 04:49:28 +08:00
|
|
|
size = ALIGN(__size + sizeof(u32), sizeof(u64));
|
|
|
|
size -= sizeof(u32);
|
2010-03-05 12:35:37 +08:00
|
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
2009-09-26 02:20:12 +08:00
|
|
|
"profile buffer not large enough"))
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
2009-11-22 12:26:55 +08:00
|
|
|
|
2010-05-21 23:49:57 +08:00
|
|
|
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
|
2010-01-28 09:32:29 +08:00
|
|
|
if (!entry)
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
2009-09-26 02:20:12 +08:00
|
|
|
|
|
|
|
entry->ip = (unsigned long)kp->addr;
|
2010-07-06 02:54:45 +08:00
|
|
|
memset(&entry[1], 0, dsize);
|
|
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
tracing, perf_events: Protect the buffer from recursion in perf
While tracing using events with perf, if one enables the
lockdep:lock_acquire event, it will infect every other perf
trace events.
Basically, you can enable whatever set of trace events through
perf but if this event is part of the set, the only result we
can get is a long list of lock_acquire events of rcu read lock,
and only that.
This is because of a recursion inside perf.
1) When a trace event is triggered, it will fill a per cpu
buffer and submit it to perf.
2) Perf will commit this event but will also protect some data
using rcu_read_lock
3) A recursion appears: rcu_read_lock triggers a lock_acquire
event that will fill the per cpu event and then submit the
buffer to perf.
4) Perf detects a recursion and ignores it
5) Perf continues its work on the previous event, but its buffer
has been overwritten by the lock_acquire event, it has then
been turned into a lock_acquire event of rcu read lock
Such scenario also happens with lock_release with
rcu_read_unlock().
We could turn the rcu_read_lock() into __rcu_read_lock() to drop
the lock debugging from perf fast path, but that would make us
lose the rcu debugging and that doesn't prevent from other
possible kind of recursion from perf in the future.
This patch adds a recursion protection based on a counter on the
perf trace per cpu buffers to solve the problem.
-v2: Fixed lost whitespace, added reviewed-by tag
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1257477185-7838-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-06 11:13:05 +08:00
|
|
|
|
2010-05-21 18:31:09 +08:00
|
|
|
head = this_cpu_ptr(call->perf_events);
|
2012-07-11 22:14:58 +08:00
|
|
|
perf_trace_buf_submit(entry, size, rctx,
|
|
|
|
entry->ip, 1, regs, head, NULL);
|
2009-09-11 07:53:30 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Kretprobe profile handler */
|
2010-03-05 12:35:37 +08:00
|
|
|
static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
|
2009-09-11 07:53:30 +08:00
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
|
|
|
|
struct ftrace_event_call *call = &tp->call;
|
tracing/kprobes: Support basic types on dynamic events
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in
kprobe tracer. With this patch, users can specify above basic types on
each arguments after ':'. If omitted, the argument type is set as
unsigned long (u32 or u64, arch-dependent).
e.g.
echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events
adds a probe recording hardirq_offset in signed-32bits value on the
entry of account_system_time.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-13 01:17:08 +08:00
|
|
|
struct kretprobe_trace_entry_head *entry;
|
2010-05-19 20:02:22 +08:00
|
|
|
struct hlist_head *head;
|
2010-07-06 02:54:45 +08:00
|
|
|
int size, __size, dsize;
|
2009-11-23 18:37:29 +08:00
|
|
|
int rctx;
|
2009-09-11 07:53:30 +08:00
|
|
|
|
2010-07-06 02:54:45 +08:00
|
|
|
dsize = __get_data_size(tp, regs);
|
|
|
|
__size = sizeof(*entry) + tp->size + dsize;
|
2009-09-15 04:49:28 +08:00
|
|
|
size = ALIGN(__size + sizeof(u32), sizeof(u64));
|
|
|
|
size -= sizeof(u32);
|
2010-03-05 12:35:37 +08:00
|
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
2009-09-26 02:20:12 +08:00
|
|
|
"profile buffer not large enough"))
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
tracing, perf_events: Protect the buffer from recursion in perf
While tracing using events with perf, if one enables the
lockdep:lock_acquire event, it will infect every other perf
trace events.
Basically, you can enable whatever set of trace events through
perf but if this event is part of the set, the only result we
can get is a long list of lock_acquire events of rcu read lock,
and only that.
This is because of a recursion inside perf.
1) When a trace event is triggered, it will fill a per cpu
buffer and submit it to perf.
2) Perf will commit this event but will also protect some data
using rcu_read_lock
3) A recursion appears: rcu_read_lock triggers a lock_acquire
event that will fill the per cpu event and then submit the
buffer to perf.
4) Perf detects a recursion and ignores it
5) Perf continues its work on the previous event, but its buffer
has been overwritten by the lock_acquire event, it has then
been turned into a lock_acquire event of rcu read lock
Such scenario also happens with lock_release with
rcu_read_unlock().
We could turn the rcu_read_lock() into __rcu_read_lock() to drop
the lock debugging from perf fast path, but that would make us
lose the rcu debugging and that doesn't prevent from other
possible kind of recursion from perf in the future.
This patch adds a recursion protection based on a counter on the
perf trace per cpu buffers to solve the problem.
-v2: Fixed lost whitespace, added reviewed-by tag
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1257477185-7838-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-06 11:13:05 +08:00
|
|
|
|
2010-05-21 23:49:57 +08:00
|
|
|
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
|
2010-01-28 09:32:29 +08:00
|
|
|
if (!entry)
|
2010-01-28 09:34:27 +08:00
|
|
|
return;
|
2009-09-11 07:53:30 +08:00
|
|
|
|
2009-09-26 02:20:12 +08:00
|
|
|
entry->func = (unsigned long)tp->rp.kp.addr;
|
|
|
|
entry->ret_ip = (unsigned long)ri->ret_addr;
|
2010-07-06 02:54:45 +08:00
|
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
tracing, perf_events: Protect the buffer from recursion in perf
While tracing using events with perf, if one enables the
lockdep:lock_acquire event, it will infect every other perf
trace events.
Basically, you can enable whatever set of trace events through
perf but if this event is part of the set, the only result we
can get is a long list of lock_acquire events of rcu read lock,
and only that.
This is because of a recursion inside perf.
1) When a trace event is triggered, it will fill a per cpu
buffer and submit it to perf.
2) Perf will commit this event but will also protect some data
using rcu_read_lock
3) A recursion appears: rcu_read_lock triggers a lock_acquire
event that will fill the per cpu event and then submit the
buffer to perf.
4) Perf detects a recursion and ignores it
5) Perf continues its work on the previous event, but its buffer
has been overwritten by the lock_acquire event, it has then
been turned into a lock_acquire event of rcu read lock
Such scenario also happens with lock_release with
rcu_read_unlock().
We could turn the rcu_read_lock() into __rcu_read_lock() to drop
the lock debugging from perf fast path, but that would make us
lose the rcu debugging and that doesn't prevent from other
possible kind of recursion from perf in the future.
This patch adds a recursion protection based on a counter on the
perf trace per cpu buffers to solve the problem.
-v2: Fixed lost whitespace, added reviewed-by tag
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <1257477185-7838-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-06 11:13:05 +08:00
|
|
|
|
2010-05-21 18:31:09 +08:00
|
|
|
head = this_cpu_ptr(call->perf_events);
|
2012-07-11 22:14:58 +08:00
|
|
|
perf_trace_buf_submit(entry, size, rctx,
|
|
|
|
entry->ret_ip, 1, regs, head, NULL);
|
2009-09-11 07:53:30 +08:00
|
|
|
}
|
2009-12-21 14:27:35 +08:00
|
|
|
#endif /* CONFIG_PERF_EVENTS */
|
2009-09-15 04:49:20 +08:00
|
|
|
|
2010-04-22 00:27:06 +08:00
|
|
|
static __kprobes
|
2012-02-15 22:51:49 +08:00
|
|
|
int kprobe_register(struct ftrace_event_call *event,
|
|
|
|
enum trace_reg type, void *data)
|
2010-04-22 00:27:06 +08:00
|
|
|
{
|
2011-06-27 15:26:44 +08:00
|
|
|
struct trace_probe *tp = (struct trace_probe *)event->data;
|
|
|
|
|
2010-04-22 00:27:06 +08:00
|
|
|
switch (type) {
|
|
|
|
case TRACE_REG_REGISTER:
|
2011-06-27 15:26:44 +08:00
|
|
|
return enable_trace_probe(tp, TP_FLAG_TRACE);
|
2010-04-22 00:27:06 +08:00
|
|
|
case TRACE_REG_UNREGISTER:
|
2011-06-27 15:26:44 +08:00
|
|
|
disable_trace_probe(tp, TP_FLAG_TRACE);
|
2010-04-22 00:27:06 +08:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
|
|
case TRACE_REG_PERF_REGISTER:
|
2011-06-27 15:26:44 +08:00
|
|
|
return enable_trace_probe(tp, TP_FLAG_PROFILE);
|
2010-04-22 00:27:06 +08:00
|
|
|
case TRACE_REG_PERF_UNREGISTER:
|
2011-06-27 15:26:44 +08:00
|
|
|
disable_trace_probe(tp, TP_FLAG_PROFILE);
|
2010-04-22 00:27:06 +08:00
|
|
|
return 0;
|
2012-02-15 22:51:49 +08:00
|
|
|
case TRACE_REG_PERF_OPEN:
|
|
|
|
case TRACE_REG_PERF_CLOSE:
|
2012-02-15 22:51:50 +08:00
|
|
|
case TRACE_REG_PERF_ADD:
|
|
|
|
case TRACE_REG_PERF_DEL:
|
2012-02-15 22:51:49 +08:00
|
|
|
return 0;
|
2010-04-22 00:27:06 +08:00
|
|
|
#endif
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
2009-09-15 04:49:20 +08:00
|
|
|
|
|
|
|
static __kprobes
|
|
|
|
int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
|
2009-09-11 07:53:30 +08:00
|
|
|
|
2013-05-09 13:44:36 +08:00
|
|
|
tp->nhit++;
|
|
|
|
|
2009-09-15 04:49:20 +08:00
|
|
|
if (tp->flags & TP_FLAG_TRACE)
|
|
|
|
kprobe_trace_func(kp, regs);
|
2009-12-21 14:27:35 +08:00
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
2009-09-15 04:49:20 +08:00
|
|
|
if (tp->flags & TP_FLAG_PROFILE)
|
2010-03-05 12:35:37 +08:00
|
|
|
kprobe_perf_func(kp, regs);
|
2009-12-21 14:27:35 +08:00
|
|
|
#endif
|
2009-09-15 04:49:20 +08:00
|
|
|
return 0; /* We don't tweek kernel, so just return 0 */
|
|
|
|
}
|
|
|
|
|
|
|
|
static __kprobes
|
|
|
|
int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
|
|
|
|
|
2013-05-09 13:44:36 +08:00
|
|
|
tp->nhit++;
|
|
|
|
|
2009-09-15 04:49:20 +08:00
|
|
|
if (tp->flags & TP_FLAG_TRACE)
|
|
|
|
kretprobe_trace_func(ri, regs);
|
2009-12-21 14:27:35 +08:00
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
2009-09-15 04:49:20 +08:00
|
|
|
if (tp->flags & TP_FLAG_PROFILE)
|
2010-03-05 12:35:37 +08:00
|
|
|
kretprobe_perf_func(ri, regs);
|
2009-12-21 14:27:35 +08:00
|
|
|
#endif
|
2009-09-15 04:49:20 +08:00
|
|
|
return 0; /* We don't tweek kernel, so just return 0 */
|
|
|
|
}
|
2009-09-11 07:53:30 +08:00
|
|
|
|
2010-04-23 06:46:14 +08:00
|
|
|
static struct trace_event_functions kretprobe_funcs = {
|
|
|
|
.trace = print_kretprobe_event
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct trace_event_functions kprobe_funcs = {
|
|
|
|
.trace = print_kprobe_event
|
|
|
|
};
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
static int register_probe_event(struct trace_probe *tp)
|
|
|
|
{
|
|
|
|
struct ftrace_event_call *call = &tp->call;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
/* Initialize ftrace_event_call */
|
2010-05-24 16:24:52 +08:00
|
|
|
INIT_LIST_HEAD(&call->class->fields);
|
2011-06-27 15:26:36 +08:00
|
|
|
if (trace_probe_is_return(tp)) {
|
2010-04-23 22:00:22 +08:00
|
|
|
call->event.funcs = &kretprobe_funcs;
|
2010-04-22 22:35:55 +08:00
|
|
|
call->class->define_fields = kretprobe_event_define_fields;
|
2009-08-14 04:35:11 +08:00
|
|
|
} else {
|
2010-04-23 22:00:22 +08:00
|
|
|
call->event.funcs = &kprobe_funcs;
|
2010-04-22 22:35:55 +08:00
|
|
|
call->class->define_fields = kprobe_event_define_fields;
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
2009-12-15 15:39:49 +08:00
|
|
|
if (set_print_fmt(tp) < 0)
|
|
|
|
return -ENOMEM;
|
2010-04-23 22:38:03 +08:00
|
|
|
ret = register_ftrace_event(&call->event);
|
|
|
|
if (!ret) {
|
2009-12-15 15:39:49 +08:00
|
|
|
kfree(call->print_fmt);
|
2009-08-14 04:35:34 +08:00
|
|
|
return -ENODEV;
|
2009-12-15 15:39:49 +08:00
|
|
|
}
|
2010-04-23 23:12:36 +08:00
|
|
|
call->flags = 0;
|
2010-04-22 00:27:06 +08:00
|
|
|
call->class->reg = kprobe_register;
|
2009-08-14 04:35:11 +08:00
|
|
|
call->data = tp;
|
|
|
|
ret = trace_add_event_call(call);
|
2009-08-14 04:35:34 +08:00
|
|
|
if (ret) {
|
2009-08-14 04:35:11 +08:00
|
|
|
pr_info("Failed to register kprobe event: %s\n", call->name);
|
2009-12-15 15:39:49 +08:00
|
|
|
kfree(call->print_fmt);
|
2010-04-23 22:00:22 +08:00
|
|
|
unregister_ftrace_event(&call->event);
|
2009-08-14 04:35:34 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void unregister_probe_event(struct trace_probe *tp)
|
|
|
|
{
|
2009-08-14 04:35:34 +08:00
|
|
|
/* tp->event is unregistered in trace_remove_event_call() */
|
2009-08-14 04:35:11 +08:00
|
|
|
trace_remove_event_call(&tp->call);
|
2009-12-15 15:39:49 +08:00
|
|
|
kfree(tp->call.print_fmt);
|
2009-08-14 04:35:11 +08:00
|
|
|
}
|
|
|
|
|
2011-03-31 09:57:33 +08:00
|
|
|
/* Make a debugfs interface for controlling probe points */
|
2009-08-14 04:35:11 +08:00
|
|
|
static __init int init_kprobe_trace(void)
|
|
|
|
{
|
|
|
|
struct dentry *d_tracer;
|
|
|
|
struct dentry *entry;
|
|
|
|
|
2011-06-27 15:26:56 +08:00
|
|
|
if (register_module_notifier(&trace_probe_module_nb))
|
|
|
|
return -EINVAL;
|
|
|
|
|
2009-08-14 04:35:11 +08:00
|
|
|
d_tracer = tracing_init_dentry();
|
|
|
|
if (!d_tracer)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
entry = debugfs_create_file("kprobe_events", 0644, d_tracer,
|
|
|
|
NULL, &kprobe_events_ops);
|
|
|
|
|
2009-08-14 04:35:42 +08:00
|
|
|
/* Event list interface */
|
2009-08-14 04:35:11 +08:00
|
|
|
if (!entry)
|
|
|
|
pr_warning("Could not create debugfs "
|
|
|
|
"'kprobe_events' entry\n");
|
2009-08-14 04:35:42 +08:00
|
|
|
|
|
|
|
/* Profile interface */
|
|
|
|
entry = debugfs_create_file("kprobe_profile", 0444, d_tracer,
|
|
|
|
NULL, &kprobe_profile_ops);
|
|
|
|
|
|
|
|
if (!entry)
|
|
|
|
pr_warning("Could not create debugfs "
|
|
|
|
"'kprobe_profile' entry\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
fs_initcall(init_kprobe_trace);
|
|
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_FTRACE_STARTUP_TEST
|
|
|
|
|
2011-06-07 10:35:13 +08:00
|
|
|
/*
|
|
|
|
* The "__used" keeps gcc from removing the function symbol
|
|
|
|
* from the kallsyms table.
|
|
|
|
*/
|
|
|
|
static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
|
|
|
|
int a4, int a5, int a6)
|
2009-08-14 04:35:11 +08:00
|
|
|
{
|
|
|
|
return a1 + a2 + a3 + a4 + a5 + a6;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __init int kprobe_trace_self_tests_init(void)
|
|
|
|
{
|
2010-01-14 13:12:12 +08:00
|
|
|
int ret, warn = 0;
|
2009-08-14 04:35:11 +08:00
|
|
|
int (*target)(int, int, int, int, int, int);
|
2010-01-14 13:12:12 +08:00
|
|
|
struct trace_probe *tp;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
target = kprobe_trace_selftest_target;
|
|
|
|
|
|
|
|
pr_info("Testing kprobe tracing: ");
|
|
|
|
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target "
|
|
|
|
"$stack $stack0 +0($stack)",
|
|
|
|
create_trace_probe);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(ret)) {
|
|
|
|
pr_warning("error on probing function entry.\n");
|
|
|
|
warn++;
|
|
|
|
} else {
|
|
|
|
/* Enable trace point */
|
2011-06-27 15:26:36 +08:00
|
|
|
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
|
|
pr_warning("error on getting new probe.\n");
|
|
|
|
warn++;
|
|
|
|
} else
|
2011-06-27 15:26:44 +08:00
|
|
|
enable_trace_probe(tp, TP_FLAG_TRACE);
|
2010-01-14 13:12:12 +08:00
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target "
|
|
|
|
"$retval", create_trace_probe);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(ret)) {
|
|
|
|
pr_warning("error on probing function return.\n");
|
|
|
|
warn++;
|
|
|
|
} else {
|
|
|
|
/* Enable trace point */
|
2011-06-27 15:26:36 +08:00
|
|
|
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
|
|
pr_warning("error on getting new probe.\n");
|
|
|
|
warn++;
|
|
|
|
} else
|
2011-06-27 15:26:44 +08:00
|
|
|
enable_trace_probe(tp, TP_FLAG_TRACE);
|
2010-01-14 13:12:12 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
if (warn)
|
|
|
|
goto end;
|
2009-08-14 04:35:11 +08:00
|
|
|
|
|
|
|
ret = target(1, 2, 3, 4, 5, 6);
|
|
|
|
|
2011-10-04 18:44:38 +08:00
|
|
|
/* Disable trace points before removing it */
|
|
|
|
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
|
|
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
|
|
pr_warning("error on getting test probe.\n");
|
|
|
|
warn++;
|
|
|
|
} else
|
|
|
|
disable_trace_probe(tp, TP_FLAG_TRACE);
|
|
|
|
|
|
|
|
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
|
|
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
|
|
pr_warning("error on getting 2nd test probe.\n");
|
|
|
|
warn++;
|
|
|
|
} else
|
|
|
|
disable_trace_probe(tp, TP_FLAG_TRACE);
|
|
|
|
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_command("-:testprobe", create_trace_probe);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(ret)) {
|
|
|
|
pr_warning("error on deleting a probe.\n");
|
|
|
|
warn++;
|
|
|
|
}
|
|
|
|
|
2012-04-09 17:11:44 +08:00
|
|
|
ret = traceprobe_command("-:testprobe2", create_trace_probe);
|
2010-01-14 13:12:12 +08:00
|
|
|
if (WARN_ON_ONCE(ret)) {
|
|
|
|
pr_warning("error on deleting a probe.\n");
|
|
|
|
warn++;
|
|
|
|
}
|
2009-08-14 04:35:11 +08:00
|
|
|
|
2010-01-14 13:12:12 +08:00
|
|
|
end:
|
2011-06-27 15:26:36 +08:00
|
|
|
release_all_trace_probes();
|
2010-01-14 13:12:12 +08:00
|
|
|
if (warn)
|
|
|
|
pr_cont("NG: Some tests are failed. Please check them.\n");
|
|
|
|
else
|
|
|
|
pr_cont("OK\n");
|
2009-08-14 04:35:11 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
late_initcall(kprobe_trace_self_tests_init);
|
|
|
|
|
|
|
|
#endif
|