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3d1fc7b088
Fix a sparse warning about the rcu operated pointer is defined without __rcu address space. Link: http://lkml.kernel.org/r/20130513115837.6545.23322.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
1488 lines
36 KiB
C
1488 lines
36 KiB
C
/*
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* Kprobes-based tracing events
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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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#include "trace_probe.h"
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#define KPROBE_EVENT_SYSTEM "kprobes"
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/**
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* Kprobe event core functions
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*/
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struct trace_probe {
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struct list_head list;
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struct kretprobe rp; /* Use rp.kp for kprobe use */
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unsigned long nhit;
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unsigned int flags; /* For TP_FLAG_* */
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const char *symbol; /* symbol name */
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struct ftrace_event_class class;
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struct ftrace_event_call call;
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struct ftrace_event_file * __rcu *files;
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ssize_t size; /* trace entry size */
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unsigned int nr_args;
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struct probe_arg args[];
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};
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#define SIZEOF_TRACE_PROBE(n) \
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(offsetof(struct trace_probe, args) + \
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(sizeof(struct probe_arg) * (n)))
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static __kprobes bool trace_probe_is_return(struct trace_probe *tp)
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{
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return tp->rp.handler != NULL;
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}
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static __kprobes const char *trace_probe_symbol(struct trace_probe *tp)
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{
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return tp->symbol ? tp->symbol : "unknown";
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}
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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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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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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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/*
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* Allocate new trace_probe and initialize it (including kprobes).
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*/
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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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void *addr,
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const char *symbol,
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unsigned long offs,
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int nargs, bool is_return)
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{
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struct trace_probe *tp;
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int ret = -ENOMEM;
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tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);
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if (!tp)
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return ERR_PTR(ret);
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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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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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tp->rp.handler = kretprobe_dispatcher;
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else
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tp->rp.kp.pre_handler = kprobe_dispatcher;
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if (!event || !is_good_name(event)) {
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ret = -EINVAL;
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goto error;
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}
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tp->call.class = &tp->class;
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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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if (!group || !is_good_name(group)) {
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ret = -EINVAL;
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goto error;
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}
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tp->class.system = kstrdup(group, GFP_KERNEL);
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if (!tp->class.system)
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goto error;
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INIT_LIST_HEAD(&tp->list);
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return tp;
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error:
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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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return ERR_PTR(ret);
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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++)
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traceprobe_free_probe_arg(&tp->args[i]);
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kfree(tp->call.class->system);
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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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static struct trace_probe *find_trace_probe(const char *event,
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const char *group)
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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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if (strcmp(tp->call.name, event) == 0 &&
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strcmp(tp->call.class->system, group) == 0)
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return tp;
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return NULL;
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}
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static int trace_probe_nr_files(struct trace_probe *tp)
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{
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struct ftrace_event_file **file;
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int ret = 0;
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/*
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* Since all tp->files updater is protected by probe_enable_lock,
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* we don't need to lock an rcu_read_lock.
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*/
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file = rcu_dereference_raw(tp->files);
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if (file)
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while (*(file++))
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ret++;
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return ret;
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}
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static DEFINE_MUTEX(probe_enable_lock);
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/*
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* Enable trace_probe
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* if the file is NULL, enable "perf" handler, or enable "trace" handler.
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*/
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static int
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enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
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{
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int ret = 0;
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mutex_lock(&probe_enable_lock);
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if (file) {
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struct ftrace_event_file **new, **old;
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int n = trace_probe_nr_files(tp);
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old = rcu_dereference_raw(tp->files);
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/* 1 is for new one and 1 is for stopper */
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new = kzalloc((n + 2) * sizeof(struct ftrace_event_file *),
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GFP_KERNEL);
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if (!new) {
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ret = -ENOMEM;
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goto out_unlock;
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}
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memcpy(new, old, n * sizeof(struct ftrace_event_file *));
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new[n] = file;
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/* The last one keeps a NULL */
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rcu_assign_pointer(tp->files, new);
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tp->flags |= TP_FLAG_TRACE;
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if (old) {
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/* Make sure the probe is done with old files */
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synchronize_sched();
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kfree(old);
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}
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} else
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tp->flags |= TP_FLAG_PROFILE;
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if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) &&
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!trace_probe_has_gone(tp)) {
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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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out_unlock:
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mutex_unlock(&probe_enable_lock);
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return ret;
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}
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static int
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trace_probe_file_index(struct trace_probe *tp, struct ftrace_event_file *file)
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{
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struct ftrace_event_file **files;
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int i;
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/*
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* Since all tp->files updater is protected by probe_enable_lock,
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* we don't need to lock an rcu_read_lock.
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*/
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files = rcu_dereference_raw(tp->files);
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if (files) {
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for (i = 0; files[i]; i++)
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if (files[i] == file)
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return i;
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}
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return -1;
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}
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/*
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* Disable trace_probe
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* if the file is NULL, disable "perf" handler, or disable "trace" handler.
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*/
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static int
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disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file)
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{
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int ret = 0;
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mutex_lock(&probe_enable_lock);
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if (file) {
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struct ftrace_event_file **new, **old;
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int n = trace_probe_nr_files(tp);
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int i, j;
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old = rcu_dereference_raw(tp->files);
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if (n == 0 || trace_probe_file_index(tp, file) < 0) {
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ret = -EINVAL;
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goto out_unlock;
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}
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if (n == 1) { /* Remove the last file */
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tp->flags &= ~TP_FLAG_TRACE;
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new = NULL;
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} else {
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new = kzalloc(n * sizeof(struct ftrace_event_file *),
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GFP_KERNEL);
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if (!new) {
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ret = -ENOMEM;
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goto out_unlock;
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}
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/* This copy & check loop copies the NULL stopper too */
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for (i = 0, j = 0; j < n && i < n + 1; i++)
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if (old[i] != file)
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new[j++] = old[i];
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}
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rcu_assign_pointer(tp->files, new);
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/* Make sure the probe is done with old files */
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synchronize_sched();
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kfree(old);
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} else
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tp->flags &= ~TP_FLAG_PROFILE;
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if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) {
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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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disable_kprobe(&tp->rp.kp);
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}
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out_unlock:
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mutex_unlock(&probe_enable_lock);
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return ret;
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}
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/* Internal register function - just handle k*probes and flags */
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static int __register_trace_probe(struct trace_probe *tp)
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{
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int i, ret;
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if (trace_probe_is_registered(tp))
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return -EINVAL;
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for (i = 0; i < tp->nr_args; i++)
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traceprobe_update_arg(&tp->args[i]);
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/* Set/clear disabled flag according to tp->flag */
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if (trace_probe_is_enabled(tp))
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tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
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else
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tp->rp.kp.flags |= KPROBE_FLAG_DISABLED;
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if (trace_probe_is_return(tp))
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ret = register_kretprobe(&tp->rp);
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else
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ret = register_kprobe(&tp->rp.kp);
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if (ret == 0)
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tp->flags |= TP_FLAG_REGISTERED;
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else {
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pr_warning("Could not insert probe at %s+%lu: %d\n",
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trace_probe_symbol(tp), trace_probe_offset(tp), ret);
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if (ret == -ENOENT && trace_probe_is_on_module(tp)) {
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pr_warning("This probe might be able to register after"
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"target module is loaded. Continue.\n");
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ret = 0;
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} else if (ret == -EILSEQ) {
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pr_warning("Probing address(0x%p) is not an "
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"instruction boundary.\n",
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tp->rp.kp.addr);
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ret = -EINVAL;
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}
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}
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return ret;
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}
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|
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/* Internal unregister function - just handle k*probes and flags */
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static void __unregister_trace_probe(struct trace_probe *tp)
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{
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if (trace_probe_is_registered(tp)) {
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if (trace_probe_is_return(tp))
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unregister_kretprobe(&tp->rp);
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else
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unregister_kprobe(&tp->rp.kp);
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tp->flags &= ~TP_FLAG_REGISTERED;
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/* Cleanup kprobe for reuse */
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if (tp->rp.kp.symbol_name)
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tp->rp.kp.addr = NULL;
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}
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}
|
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|
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/* Unregister a trace_probe and probe_event: call with locking probe_lock */
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static int unregister_trace_probe(struct trace_probe *tp)
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{
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/* Enabled event can not be unregistered */
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if (trace_probe_is_enabled(tp))
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return -EBUSY;
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|
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__unregister_trace_probe(tp);
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list_del(&tp->list);
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unregister_probe_event(tp);
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return 0;
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}
|
|
|
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/* Register a trace_probe and probe_event */
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static int register_trace_probe(struct trace_probe *tp)
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{
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struct trace_probe *old_tp;
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int ret;
|
|
|
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mutex_lock(&probe_lock);
|
|
|
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/* Delete old (same name) event if exist */
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old_tp = find_trace_probe(tp->call.name, tp->call.class->system);
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if (old_tp) {
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ret = unregister_trace_probe(old_tp);
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if (ret < 0)
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goto end;
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free_trace_probe(old_tp);
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}
|
|
|
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/* Register new event */
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ret = register_probe_event(tp);
|
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if (ret) {
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pr_warning("Failed to register probe event(%d)\n", ret);
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goto end;
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}
|
|
|
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/* Register k*probe */
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ret = __register_trace_probe(tp);
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if (ret < 0)
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unregister_probe_event(tp);
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else
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list_add_tail(&tp->list, &probe_list);
|
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|
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end:
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mutex_unlock(&probe_lock);
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return ret;
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}
|
|
|
|
/* Module notifier call back, checking event on the module */
|
|
static int trace_probe_module_callback(struct notifier_block *nb,
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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)) {
|
|
/* Don't need to check busy - this should have gone. */
|
|
__unregister_trace_probe(tp);
|
|
ret = __register_trace_probe(tp);
|
|
if (ret)
|
|
pr_warning("Failed to re-register probe %s on"
|
|
"%s: %d\n",
|
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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 */
|
|
};
|
|
|
|
static int create_trace_probe(int argc, char **argv)
|
|
{
|
|
/*
|
|
* Argument syntax:
|
|
* - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
|
|
* - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
|
|
* Fetch args:
|
|
* $retval : fetch return value
|
|
* $stack : fetch stack address
|
|
* $stackN : fetch Nth of stack (N:0-)
|
|
* @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
|
|
* Dereferencing memory fetch:
|
|
* +|-offs(ARG) : fetch memory at ARG +|- offs address.
|
|
* Alias name of args:
|
|
* NAME=FETCHARG : set NAME as alias of FETCHARG.
|
|
* Type of args:
|
|
* FETCHARG:TYPE : use TYPE instead of unsigned long.
|
|
*/
|
|
struct trace_probe *tp;
|
|
int i, ret = 0;
|
|
bool is_return = false, is_delete = false;
|
|
char *symbol = NULL, *event = NULL, *group = NULL;
|
|
char *arg;
|
|
unsigned long offset = 0;
|
|
void *addr = NULL;
|
|
char buf[MAX_EVENT_NAME_LEN];
|
|
|
|
/* argc must be >= 1 */
|
|
if (argv[0][0] == 'p')
|
|
is_return = false;
|
|
else if (argv[0][0] == 'r')
|
|
is_return = true;
|
|
else if (argv[0][0] == '-')
|
|
is_delete = true;
|
|
else {
|
|
pr_info("Probe definition must be started with 'p', 'r' or"
|
|
" '-'.\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (argv[0][1] == ':') {
|
|
event = &argv[0][2];
|
|
if (strchr(event, '/')) {
|
|
group = event;
|
|
event = strchr(group, '/') + 1;
|
|
event[-1] = '\0';
|
|
if (strlen(group) == 0) {
|
|
pr_info("Group name is not specified\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
if (strlen(event) == 0) {
|
|
pr_info("Event name is not specified\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
if (!group)
|
|
group = KPROBE_EVENT_SYSTEM;
|
|
|
|
if (is_delete) {
|
|
if (!event) {
|
|
pr_info("Delete command needs an event name.\n");
|
|
return -EINVAL;
|
|
}
|
|
mutex_lock(&probe_lock);
|
|
tp = find_trace_probe(event, group);
|
|
if (!tp) {
|
|
mutex_unlock(&probe_lock);
|
|
pr_info("Event %s/%s doesn't exist.\n", group, event);
|
|
return -ENOENT;
|
|
}
|
|
/* delete an event */
|
|
ret = unregister_trace_probe(tp);
|
|
if (ret == 0)
|
|
free_trace_probe(tp);
|
|
mutex_unlock(&probe_lock);
|
|
return ret;
|
|
}
|
|
|
|
if (argc < 2) {
|
|
pr_info("Probe point is not specified.\n");
|
|
return -EINVAL;
|
|
}
|
|
if (isdigit(argv[1][0])) {
|
|
if (is_return) {
|
|
pr_info("Return probe point must be a symbol.\n");
|
|
return -EINVAL;
|
|
}
|
|
/* an address specified */
|
|
ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
|
|
if (ret) {
|
|
pr_info("Failed to parse address.\n");
|
|
return ret;
|
|
}
|
|
} else {
|
|
/* a symbol specified */
|
|
symbol = argv[1];
|
|
/* TODO: support .init module functions */
|
|
ret = traceprobe_split_symbol_offset(symbol, &offset);
|
|
if (ret) {
|
|
pr_info("Failed to parse symbol.\n");
|
|
return ret;
|
|
}
|
|
if (offset && is_return) {
|
|
pr_info("Return probe must be used without offset.\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
argc -= 2; argv += 2;
|
|
|
|
/* setup a probe */
|
|
if (!event) {
|
|
/* Make a new event name */
|
|
if (symbol)
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
|
|
is_return ? 'r' : 'p', symbol, offset);
|
|
else
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
|
|
is_return ? 'r' : 'p', addr);
|
|
event = buf;
|
|
}
|
|
tp = alloc_trace_probe(group, event, addr, symbol, offset, argc,
|
|
is_return);
|
|
if (IS_ERR(tp)) {
|
|
pr_info("Failed to allocate trace_probe.(%d)\n",
|
|
(int)PTR_ERR(tp));
|
|
return PTR_ERR(tp);
|
|
}
|
|
|
|
/* parse arguments */
|
|
ret = 0;
|
|
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
|
|
/* Increment count for freeing args in error case */
|
|
tp->nr_args++;
|
|
|
|
/* Parse argument name */
|
|
arg = strchr(argv[i], '=');
|
|
if (arg) {
|
|
*arg++ = '\0';
|
|
tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
|
|
} else {
|
|
arg = argv[i];
|
|
/* 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);
|
|
}
|
|
|
|
if (!tp->args[i].name) {
|
|
pr_info("Failed to allocate argument[%d] name.\n", i);
|
|
ret = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
if (traceprobe_conflict_field_name(tp->args[i].name,
|
|
tp->args, i)) {
|
|
pr_info("Argument[%d] name '%s' conflicts with "
|
|
"another field.\n", i, argv[i]);
|
|
ret = -EINVAL;
|
|
goto error;
|
|
}
|
|
|
|
/* Parse fetch argument */
|
|
ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i],
|
|
is_return, true);
|
|
if (ret) {
|
|
pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
ret = register_trace_probe(tp);
|
|
if (ret)
|
|
goto error;
|
|
return 0;
|
|
|
|
error:
|
|
free_trace_probe(tp);
|
|
return ret;
|
|
}
|
|
|
|
static int release_all_trace_probes(void)
|
|
{
|
|
struct trace_probe *tp;
|
|
int ret = 0;
|
|
|
|
mutex_lock(&probe_lock);
|
|
/* Ensure no probe is in use. */
|
|
list_for_each_entry(tp, &probe_list, list)
|
|
if (trace_probe_is_enabled(tp)) {
|
|
ret = -EBUSY;
|
|
goto end;
|
|
}
|
|
/* 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);
|
|
}
|
|
|
|
end:
|
|
mutex_unlock(&probe_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* 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;
|
|
int i;
|
|
|
|
seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p');
|
|
seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
|
|
|
|
if (!tp->symbol)
|
|
seq_printf(m, " 0x%p", tp->rp.kp.addr);
|
|
else if (tp->rp.kp.offset)
|
|
seq_printf(m, " %s+%u", trace_probe_symbol(tp),
|
|
tp->rp.kp.offset);
|
|
else
|
|
seq_printf(m, " %s", trace_probe_symbol(tp));
|
|
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
|
|
seq_printf(m, "\n");
|
|
|
|
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)
|
|
{
|
|
int ret;
|
|
|
|
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
|
|
ret = release_all_trace_probes();
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
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)
|
|
{
|
|
return traceprobe_probes_write(file, buffer, count, ppos,
|
|
create_trace_probe);
|
|
}
|
|
|
|
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,
|
|
};
|
|
|
|
/* 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,
|
|
tp->rp.kp.nmissed);
|
|
|
|
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,
|
|
};
|
|
|
|
/* 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);
|
|
}
|
|
}
|
|
|
|
/* Kprobe handler */
|
|
static __kprobes void
|
|
__kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs,
|
|
struct ftrace_event_file *ftrace_file)
|
|
{
|
|
struct kprobe_trace_entry_head *entry;
|
|
struct ring_buffer_event *event;
|
|
struct ring_buffer *buffer;
|
|
int size, dsize, pc;
|
|
unsigned long irq_flags;
|
|
struct ftrace_event_call *call = &tp->call;
|
|
|
|
WARN_ON(call != ftrace_file->event_call);
|
|
|
|
if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags))
|
|
return;
|
|
|
|
local_save_flags(irq_flags);
|
|
pc = preempt_count();
|
|
|
|
dsize = __get_data_size(tp, regs);
|
|
size = sizeof(*entry) + tp->size + dsize;
|
|
|
|
event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
|
|
call->event.type,
|
|
size, irq_flags, pc);
|
|
if (!event)
|
|
return;
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
entry->ip = (unsigned long)tp->rp.kp.addr;
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
|
|
|
if (!filter_current_check_discard(buffer, call, entry, event))
|
|
trace_buffer_unlock_commit_regs(buffer, event,
|
|
irq_flags, pc, regs);
|
|
}
|
|
|
|
static __kprobes void
|
|
kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs)
|
|
{
|
|
/*
|
|
* Note: preempt is already disabled around the kprobe handler.
|
|
* However, we still need an smp_read_barrier_depends() corresponding
|
|
* to smp_wmb() in rcu_assign_pointer() to access the pointer.
|
|
*/
|
|
struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
|
|
|
|
if (unlikely(!file))
|
|
return;
|
|
|
|
while (*file) {
|
|
__kprobe_trace_func(tp, regs, *file);
|
|
file++;
|
|
}
|
|
}
|
|
|
|
/* Kretprobe handler */
|
|
static __kprobes void
|
|
__kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
|
|
struct pt_regs *regs,
|
|
struct ftrace_event_file *ftrace_file)
|
|
{
|
|
struct kretprobe_trace_entry_head *entry;
|
|
struct ring_buffer_event *event;
|
|
struct ring_buffer *buffer;
|
|
int size, pc, dsize;
|
|
unsigned long irq_flags;
|
|
struct ftrace_event_call *call = &tp->call;
|
|
|
|
WARN_ON(call != ftrace_file->event_call);
|
|
|
|
if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags))
|
|
return;
|
|
|
|
local_save_flags(irq_flags);
|
|
pc = preempt_count();
|
|
|
|
dsize = __get_data_size(tp, regs);
|
|
size = sizeof(*entry) + tp->size + dsize;
|
|
|
|
event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
|
|
call->event.type,
|
|
size, irq_flags, pc);
|
|
if (!event)
|
|
return;
|
|
|
|
entry = ring_buffer_event_data(event);
|
|
entry->func = (unsigned long)tp->rp.kp.addr;
|
|
entry->ret_ip = (unsigned long)ri->ret_addr;
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
|
|
|
if (!filter_current_check_discard(buffer, call, entry, event))
|
|
trace_buffer_unlock_commit_regs(buffer, event,
|
|
irq_flags, pc, regs);
|
|
}
|
|
|
|
static __kprobes void
|
|
kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri,
|
|
struct pt_regs *regs)
|
|
{
|
|
/*
|
|
* Note: preempt is already disabled around the kprobe handler.
|
|
* However, we still need an smp_read_barrier_depends() corresponding
|
|
* to smp_wmb() in rcu_assign_pointer() to access the pointer.
|
|
*/
|
|
struct ftrace_event_file **file = rcu_dereference_raw(tp->files);
|
|
|
|
if (unlikely(!file))
|
|
return;
|
|
|
|
while (*file) {
|
|
__kretprobe_trace_func(tp, ri, regs, *file);
|
|
file++;
|
|
}
|
|
}
|
|
|
|
/* Event entry printers */
|
|
enum print_line_t
|
|
print_kprobe_event(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct kprobe_trace_entry_head *field;
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_probe *tp;
|
|
u8 *data;
|
|
int i;
|
|
|
|
field = (struct kprobe_trace_entry_head *)iter->ent;
|
|
tp = container_of(event, struct trace_probe, call.event);
|
|
|
|
if (!trace_seq_printf(s, "%s: (", tp->call.name))
|
|
goto partial;
|
|
|
|
if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
|
|
goto partial;
|
|
|
|
if (!trace_seq_puts(s, ")"))
|
|
goto partial;
|
|
|
|
data = (u8 *)&field[1];
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
if (!tp->args[i].type->print(s, tp->args[i].name,
|
|
data + tp->args[i].offset, field))
|
|
goto partial;
|
|
|
|
if (!trace_seq_puts(s, "\n"))
|
|
goto partial;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
partial:
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
enum print_line_t
|
|
print_kretprobe_event(struct trace_iterator *iter, int flags,
|
|
struct trace_event *event)
|
|
{
|
|
struct kretprobe_trace_entry_head *field;
|
|
struct trace_seq *s = &iter->seq;
|
|
struct trace_probe *tp;
|
|
u8 *data;
|
|
int i;
|
|
|
|
field = (struct kretprobe_trace_entry_head *)iter->ent;
|
|
tp = container_of(event, struct trace_probe, call.event);
|
|
|
|
if (!trace_seq_printf(s, "%s: (", tp->call.name))
|
|
goto partial;
|
|
|
|
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;
|
|
|
|
if (!trace_seq_puts(s, ")"))
|
|
goto partial;
|
|
|
|
data = (u8 *)&field[1];
|
|
for (i = 0; i < tp->nr_args; i++)
|
|
if (!tp->args[i].type->print(s, tp->args[i].name,
|
|
data + tp->args[i].offset, field))
|
|
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;
|
|
struct kprobe_trace_entry_head field;
|
|
struct trace_probe *tp = (struct trace_probe *)event_call->data;
|
|
|
|
DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
|
|
/* Set argument names as fields */
|
|
for (i = 0; i < tp->nr_args; i++) {
|
|
ret = trace_define_field(event_call, tp->args[i].type->fmttype,
|
|
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;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
|
|
{
|
|
int ret, i;
|
|
struct kretprobe_trace_entry_head field;
|
|
struct trace_probe *tp = (struct trace_probe *)event_call->data;
|
|
|
|
DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
|
|
DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
|
|
/* Set argument names as fields */
|
|
for (i = 0; i < tp->nr_args; i++) {
|
|
ret = trace_define_field(event_call, tp->args[i].type->fmttype,
|
|
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;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
|
|
{
|
|
int i;
|
|
int pos = 0;
|
|
|
|
const char *fmt, *arg;
|
|
|
|
if (!trace_probe_is_return(tp)) {
|
|
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++) {
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
|
|
tp->args[i].name, tp->args[i].type->fmt);
|
|
}
|
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
|
|
|
|
for (i = 0; i < tp->nr_args; i++) {
|
|
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);
|
|
}
|
|
|
|
#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;
|
|
}
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
|
|
/* Kprobe profile handler */
|
|
static __kprobes void
|
|
kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs)
|
|
{
|
|
struct ftrace_event_call *call = &tp->call;
|
|
struct kprobe_trace_entry_head *entry;
|
|
struct hlist_head *head;
|
|
int size, __size, dsize;
|
|
int rctx;
|
|
|
|
dsize = __get_data_size(tp, regs);
|
|
__size = sizeof(*entry) + tp->size + dsize;
|
|
size = ALIGN(__size + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
|
"profile buffer not large enough"))
|
|
return;
|
|
|
|
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
|
|
if (!entry)
|
|
return;
|
|
|
|
entry->ip = (unsigned long)tp->rp.kp.addr;
|
|
memset(&entry[1], 0, dsize);
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
|
|
|
head = this_cpu_ptr(call->perf_events);
|
|
perf_trace_buf_submit(entry, size, rctx,
|
|
entry->ip, 1, regs, head, NULL);
|
|
}
|
|
|
|
/* Kretprobe profile handler */
|
|
static __kprobes void
|
|
kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct ftrace_event_call *call = &tp->call;
|
|
struct kretprobe_trace_entry_head *entry;
|
|
struct hlist_head *head;
|
|
int size, __size, dsize;
|
|
int rctx;
|
|
|
|
dsize = __get_data_size(tp, regs);
|
|
__size = sizeof(*entry) + tp->size + dsize;
|
|
size = ALIGN(__size + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
|
|
"profile buffer not large enough"))
|
|
return;
|
|
|
|
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
|
|
if (!entry)
|
|
return;
|
|
|
|
entry->func = (unsigned long)tp->rp.kp.addr;
|
|
entry->ret_ip = (unsigned long)ri->ret_addr;
|
|
store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
|
|
|
|
head = this_cpu_ptr(call->perf_events);
|
|
perf_trace_buf_submit(entry, size, rctx,
|
|
entry->ret_ip, 1, regs, head, NULL);
|
|
}
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
static __kprobes
|
|
int kprobe_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data)
|
|
{
|
|
struct trace_probe *tp = (struct trace_probe *)event->data;
|
|
struct ftrace_event_file *file = data;
|
|
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return enable_trace_probe(tp, file);
|
|
case TRACE_REG_UNREGISTER:
|
|
return disable_trace_probe(tp, file);
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return enable_trace_probe(tp, NULL);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
return disable_trace_probe(tp, NULL);
|
|
case TRACE_REG_PERF_OPEN:
|
|
case TRACE_REG_PERF_CLOSE:
|
|
case TRACE_REG_PERF_ADD:
|
|
case TRACE_REG_PERF_DEL:
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static __kprobes
|
|
int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
|
|
{
|
|
struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
|
|
|
|
tp->nhit++;
|
|
|
|
if (tp->flags & TP_FLAG_TRACE)
|
|
kprobe_trace_func(tp, regs);
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
if (tp->flags & TP_FLAG_PROFILE)
|
|
kprobe_perf_func(tp, regs);
|
|
#endif
|
|
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);
|
|
|
|
tp->nhit++;
|
|
|
|
if (tp->flags & TP_FLAG_TRACE)
|
|
kretprobe_trace_func(tp, ri, regs);
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
if (tp->flags & TP_FLAG_PROFILE)
|
|
kretprobe_perf_func(tp, ri, regs);
|
|
#endif
|
|
return 0; /* We don't tweek kernel, so just return 0 */
|
|
}
|
|
|
|
static struct trace_event_functions kretprobe_funcs = {
|
|
.trace = print_kretprobe_event
|
|
};
|
|
|
|
static struct trace_event_functions kprobe_funcs = {
|
|
.trace = print_kprobe_event
|
|
};
|
|
|
|
static int register_probe_event(struct trace_probe *tp)
|
|
{
|
|
struct ftrace_event_call *call = &tp->call;
|
|
int ret;
|
|
|
|
/* Initialize ftrace_event_call */
|
|
INIT_LIST_HEAD(&call->class->fields);
|
|
if (trace_probe_is_return(tp)) {
|
|
call->event.funcs = &kretprobe_funcs;
|
|
call->class->define_fields = kretprobe_event_define_fields;
|
|
} else {
|
|
call->event.funcs = &kprobe_funcs;
|
|
call->class->define_fields = kprobe_event_define_fields;
|
|
}
|
|
if (set_print_fmt(tp) < 0)
|
|
return -ENOMEM;
|
|
ret = register_ftrace_event(&call->event);
|
|
if (!ret) {
|
|
kfree(call->print_fmt);
|
|
return -ENODEV;
|
|
}
|
|
call->flags = 0;
|
|
call->class->reg = kprobe_register;
|
|
call->data = tp;
|
|
ret = trace_add_event_call(call);
|
|
if (ret) {
|
|
pr_info("Failed to register kprobe event: %s\n", call->name);
|
|
kfree(call->print_fmt);
|
|
unregister_ftrace_event(&call->event);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void unregister_probe_event(struct trace_probe *tp)
|
|
{
|
|
/* tp->event is unregistered in trace_remove_event_call() */
|
|
trace_remove_event_call(&tp->call);
|
|
kfree(tp->call.print_fmt);
|
|
}
|
|
|
|
/* Make a debugfs interface for controlling probe points */
|
|
static __init int init_kprobe_trace(void)
|
|
{
|
|
struct dentry *d_tracer;
|
|
struct dentry *entry;
|
|
|
|
if (register_module_notifier(&trace_probe_module_nb))
|
|
return -EINVAL;
|
|
|
|
d_tracer = tracing_init_dentry();
|
|
if (!d_tracer)
|
|
return 0;
|
|
|
|
entry = debugfs_create_file("kprobe_events", 0644, d_tracer,
|
|
NULL, &kprobe_events_ops);
|
|
|
|
/* Event list interface */
|
|
if (!entry)
|
|
pr_warning("Could not create debugfs "
|
|
"'kprobe_events' entry\n");
|
|
|
|
/* 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");
|
|
return 0;
|
|
}
|
|
fs_initcall(init_kprobe_trace);
|
|
|
|
|
|
#ifdef CONFIG_FTRACE_STARTUP_TEST
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
return a1 + a2 + a3 + a4 + a5 + a6;
|
|
}
|
|
|
|
static struct ftrace_event_file *
|
|
find_trace_probe_file(struct trace_probe *tp, struct trace_array *tr)
|
|
{
|
|
struct ftrace_event_file *file;
|
|
|
|
list_for_each_entry(file, &tr->events, list)
|
|
if (file->event_call == &tp->call)
|
|
return file;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static __init int kprobe_trace_self_tests_init(void)
|
|
{
|
|
int ret, warn = 0;
|
|
int (*target)(int, int, int, int, int, int);
|
|
struct trace_probe *tp;
|
|
struct ftrace_event_file *file;
|
|
|
|
target = kprobe_trace_selftest_target;
|
|
|
|
pr_info("Testing kprobe tracing: ");
|
|
|
|
ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target "
|
|
"$stack $stack0 +0($stack)",
|
|
create_trace_probe);
|
|
if (WARN_ON_ONCE(ret)) {
|
|
pr_warn("error on probing function entry.\n");
|
|
warn++;
|
|
} else {
|
|
/* Enable trace point */
|
|
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
pr_warn("error on getting new probe.\n");
|
|
warn++;
|
|
} else {
|
|
file = find_trace_probe_file(tp, top_trace_array());
|
|
if (WARN_ON_ONCE(file == NULL)) {
|
|
pr_warn("error on getting probe file.\n");
|
|
warn++;
|
|
} else
|
|
enable_trace_probe(tp, file);
|
|
}
|
|
}
|
|
|
|
ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target "
|
|
"$retval", create_trace_probe);
|
|
if (WARN_ON_ONCE(ret)) {
|
|
pr_warn("error on probing function return.\n");
|
|
warn++;
|
|
} else {
|
|
/* Enable trace point */
|
|
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
pr_warn("error on getting 2nd new probe.\n");
|
|
warn++;
|
|
} else {
|
|
file = find_trace_probe_file(tp, top_trace_array());
|
|
if (WARN_ON_ONCE(file == NULL)) {
|
|
pr_warn("error on getting probe file.\n");
|
|
warn++;
|
|
} else
|
|
enable_trace_probe(tp, file);
|
|
}
|
|
}
|
|
|
|
if (warn)
|
|
goto end;
|
|
|
|
ret = target(1, 2, 3, 4, 5, 6);
|
|
|
|
/* Disable trace points before removing it */
|
|
tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
pr_warn("error on getting test probe.\n");
|
|
warn++;
|
|
} else {
|
|
file = find_trace_probe_file(tp, top_trace_array());
|
|
if (WARN_ON_ONCE(file == NULL)) {
|
|
pr_warn("error on getting probe file.\n");
|
|
warn++;
|
|
} else
|
|
disable_trace_probe(tp, file);
|
|
}
|
|
|
|
tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
|
|
if (WARN_ON_ONCE(tp == NULL)) {
|
|
pr_warn("error on getting 2nd test probe.\n");
|
|
warn++;
|
|
} else {
|
|
file = find_trace_probe_file(tp, top_trace_array());
|
|
if (WARN_ON_ONCE(file == NULL)) {
|
|
pr_warn("error on getting probe file.\n");
|
|
warn++;
|
|
} else
|
|
disable_trace_probe(tp, file);
|
|
}
|
|
|
|
ret = traceprobe_command("-:testprobe", create_trace_probe);
|
|
if (WARN_ON_ONCE(ret)) {
|
|
pr_warn("error on deleting a probe.\n");
|
|
warn++;
|
|
}
|
|
|
|
ret = traceprobe_command("-:testprobe2", create_trace_probe);
|
|
if (WARN_ON_ONCE(ret)) {
|
|
pr_warn("error on deleting a probe.\n");
|
|
warn++;
|
|
}
|
|
|
|
end:
|
|
release_all_trace_probes();
|
|
if (warn)
|
|
pr_cont("NG: Some tests are failed. Please check them.\n");
|
|
else
|
|
pr_cont("OK\n");
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(kprobe_trace_self_tests_init);
|
|
|
|
#endif
|