From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
include/linux/kprobes.h | 5 +-
include/linux/trace_events.h | 3 +
kernel/trace/trace.h | 5 +
kernel/trace/trace_kprobe.c | 248 ++++++++++++++++++++++++++++-------
kernel/trace/trace_probe.c | 4 +-
5 files changed, 218 insertions(+), 47 deletions(-)
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 687552b811fd..9dd38ca7ebb3 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -162,6 +162,8 @@ struct kretprobe {
struct kretprobe_holder *rph;
};
+struct trace_kprobe;
+
struct keventprobe {
/* tracepoint system */
const char *event_system;
@@ -169,7 +171,8 @@ struct keventprobe {
/* tracepoint event */
const char *event_name;
- struct trace_event_call *tp;
+ struct trace_event_call *event;
+ struct trace_kprobe *tk;
};
struct kretprobe_instance {
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 95195515147f..1302b81c9879 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -312,6 +312,7 @@ enum {
TRACE_EVENT_FL_TRACEPOINT_BIT,
TRACE_EVENT_FL_KPROBE_BIT,
TRACE_EVENT_FL_UPROBE_BIT,
+ TRACE_EVENT_FL_EPROBE_BIT,
};
/*
@@ -323,6 +324,7 @@ enum {
* TRACEPOINT - Event is a tracepoint
* KPROBE - Event is a kprobe
* UPROBE - Event is a uprobe
+ * EPROBE - Event is an event probe
*/
enum {
TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
@@ -332,6 +334,7 @@ enum {
TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
+ TRACE_EVENT_FL_EPROBE = (1 << TRACE_EVENT_FL_EPROBE_BIT),
};
#define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index d83bbb6859b4..e3ae52b7a1da 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1547,9 +1547,14 @@ static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
extern int register_trigger_cmds(void);
extern void clear_event_triggers(struct trace_array *tr);
+enum {
+ EVENT_TRIGGER_FL_PROBE = BIT(0),
+};
+
struct event_trigger_data {
unsigned long count;
int ref;
+ int flags;
struct event_trigger_ops *ops;
struct event_command *cmd_ops;
struct event_filter __rcu *filter;
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index f14c8f233142..45500ce7dedd 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -339,6 +339,7 @@ static struct trace_kprobe *alloc_event_kprobe(const char *group,
tk->ep->event_system = kstrdup(sys_name, GFP_KERNEL);
if (!tk->ep->event_system)
goto error;
+ tk->ep->tk = tk;
tk->rp.maxactive = maxactive;
ret = trace_probe_init(&tk->tp, event, group, false);
@@ -365,6 +366,11 @@ static struct trace_kprobe *find_trace_kprobe(const char *event,
return NULL;
}
+struct eprobe_data {
+ struct keventprobe *ep;
+ struct trace_event_file *file;
+};
+
static int eprobe_trigger_init(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
@@ -384,11 +390,126 @@ static int eprobe_trigger_print(struct seq_file *m,
return 0;
}
+static unsigned long get_event_field(struct fetch_insn *code, void *rec)
+{
+ struct ftrace_event_field *field = code->data;
+ unsigned long val;
+ void *addr;
+
+ addr = rec + field->offset;
+
+ switch (field->size) {
+ case 1:
+ if (field->is_signed)
+ val = *(char*)addr;
+ else
+ val = *(unsigned char*)addr;
+ break;
+ case 2:
+ if (field->is_signed)
+ val = *(short*)addr;
+ else
+ val = *(unsigned short*)addr;
+ break;
+ case 4:
+ if (field->is_signed)
+ val = *(int*)addr;
+ else
+ val = *(unsigned int*)addr;
+ break;
+ default:
+ if (field->is_signed)
+ val = *(long*)addr;
+ else
+ val = *(unsigned long*)addr;
+ break;
+ }
+ return val;
+}
+
+static int get_eprobe_size(struct trace_probe *tp, void *rec)
+{
+ struct probe_arg *arg;
+ int i, len, ret = 0;
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ if (unlikely(arg->dynamic)) {
+ unsigned long val;
+
+ val = get_event_field(arg->code, rec);
+ len = process_fetch_insn_bottom(arg->code + 1, val, NULL, NULL);
+ if (len > 0)
+ ret += len;
+ }
+ }
+
+ return ret;
+}
+
+static inline void
+store_event_args(void *data, struct trace_probe *tp, void *rec,
+ int header_size, int maxlen)
+{
+ struct probe_arg *arg;
+ unsigned long val;
+ void *base = data - header_size;
+ void *dyndata = data + tp->size;
+ u32 *dl; /* Data location */
+ int ret, i;
+
+ for (i = 0; i < tp->nr_args; i++) {
+ arg = tp->args + i;
+ dl = data + arg->offset;
+ /* Point the dynamic data area if needed */
+ if (unlikely(arg->dynamic))
+ *dl = make_data_loc(maxlen, dyndata - base);
+ val = get_event_field(arg->code, rec);
+ ret = process_fetch_insn_bottom(arg->code + 1, val, dl, base);
+ if (unlikely(ret < 0 && arg->dynamic)) {
+ *dl = make_data_loc(0, dyndata - base);
+ } else {
+ dyndata += ret;
+ maxlen -= ret;
+ }
+ }
+}
+
static void eprobe_trigger_func(struct event_trigger_data *data,
struct trace_buffer *buffer, void *rec,
struct ring_buffer_event *rbe)
{
- /* ToDo */
+ struct kprobe_trace_entry_head *entry;
+ struct eprobe_data *edata = data->private_data;
+ struct keventprobe *ep = edata->ep;
+ struct trace_event_file *trace_file = edata->file;
+ struct trace_kprobe *tk = ep->tk;
+ struct trace_event_call *call = trace_probe_event_call(&tk->tp);
+ struct trace_event_buffer fbuffer;
+ int dsize;
+
+ if (trace_trigger_soft_disabled(edata->file))
+ return;
+
+ fbuffer.trace_ctx = tracing_gen_ctx();
+ fbuffer.trace_file = trace_file;
+
+ dsize = get_eprobe_size(&tk->tp, rec);
+
+ fbuffer.event =
+ trace_event_buffer_lock_reserve(&fbuffer.buffer, trace_file,
+ call->event.type,
+ sizeof(*entry) + tk->tp.size + dsize,
+ fbuffer.trace_ctx);
+ if (!fbuffer.event)
+ return;
+
+ fbuffer.regs = 0;
+ entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
+ entry->ip = (unsigned long)tk->rp.kp.addr;
+ store_event_args(&entry[1], &tk->tp, rec, sizeof(*entry), dsize);
+
+ trace_event_buffer_commit(&fbuffer);
}
static struct event_trigger_ops eprobe_trigger_ops = {
@@ -426,9 +547,9 @@ static struct event_trigger_ops *eprobe_trigger_get_ops(char *cmd,
}
static struct event_command event_trigger_cmd = {
- .name = "kprobe",
+ .name = "eprobe",
.trigger_type = ETT_EVENT_KPROBE,
- .flags = EVENT_CMD_FL_POST_TRIGGER | EVENT_CMD_FL_NEEDS_REC,
+ .flags = EVENT_CMD_FL_NEEDS_REC,
.func = eprobe_trigger_cmd_func,
.reg = eprobe_trigger_reg_func,
.unreg = eprobe_trigger_unreg_func,
@@ -437,56 +558,87 @@ static struct event_command event_trigger_cmd = {
.set_filter = NULL,
};
-static int new_eprobe_trigger(struct event_trigger_data **trigger)
+static struct event_trigger_data *
+new_eprobe_trigger(struct keventprobe *ep, struct trace_event_file *file)
{
- int ret = 0;
-
- *trigger = kzalloc(sizeof(struct event_trigger_data), GFP_KERNEL);
- if (!(*trigger)) {
- ret = -ENOMEM;
- goto error;
+ struct event_trigger_data *trigger;
+ struct eprobe_data *edata;
+
+ edata = kzalloc(sizeof(*edata), GFP_KERNEL);
+ trigger = kzalloc(sizeof(*trigger), GFP_KERNEL);
+ if (!trigger || !edata) {
+ kfree(edata);
+ kfree(trigger);
+ return ERR_PTR(-ENOMEM);
}
- (*trigger)->count = -1;
- (*trigger)->ops = &eprobe_trigger_ops;
- (*trigger)->cmd_ops = &event_trigger_cmd;
+ trigger->flags = EVENT_TRIGGER_FL_PROBE;
+ trigger->count = -1;
+ trigger->ops = &eprobe_trigger_ops;
+ trigger->cmd_ops = &event_trigger_cmd;
- INIT_LIST_HEAD(&(*trigger)->list);
- RCU_INIT_POINTER((*trigger)->filter, NULL);
+ INIT_LIST_HEAD(&trigger->list);
+ RCU_INIT_POINTER(trigger->filter, NULL);
- return ret;
+ edata->ep = ep;
+ edata->file = file;
+ trigger->private_data = edata;
-error:
- return ret;
+ return trigger;
}
-static int enable_eprobe(struct keventprobe *ep, struct trace_array *tr)
+static int enable_eprobe(struct keventprobe *ep,
+ struct trace_event_file *eprobe_file)
{
- struct trace_event_file *target_event;
struct event_trigger_data *trigger;
- int ret;
+ struct trace_event_file *file;
+ struct trace_array *tr = eprobe_file->tr;
- target_event = find_event_file(tr, ep->event_system, ep->event_name);
- if (!target_event)
+ file = find_event_file(tr, ep->event_system, ep->event_name);
+ if (!file)
return -ENOENT;
- ret = new_eprobe_trigger(&trigger);
- if (!ret)
- return ret;
+ trigger = new_eprobe_trigger(ep, eprobe_file);
+ if (IS_ERR(trigger))
+ return PTR_ERR(trigger);
- list_add_tail_rcu(&trigger->list, &target_event->triggers);
+ list_add_tail_rcu(&trigger->list, &file->triggers);
- trace_event_trigger_enable_disable(target_event, 1);
+ trace_event_trigger_enable_disable(file, 1);
+ update_cond_flag(file);
return 0;
}
-static int disable_eprobe(struct keventprobe *ep)
+static int disable_eprobe(struct keventprobe *ep,
+ struct trace_array *tr)
{
+ struct event_trigger_data *trigger;
+ struct trace_event_file *file;
+ struct eprobe_data *edata;
+
+ file = find_event_file(tr, ep->event_system, ep->event_name);
+ if (!file)
+ return -ENOENT;
+
+ list_for_each_entry(trigger, &file->triggers, list) {
+ if (!(trigger->flags & EVENT_TRIGGER_FL_PROBE))
+ continue;
+ edata = trigger->private_data;
+ if (edata->ep == ep)
+ break;
+ }
+ if (list_entry_is_head(trigger, &file->triggers, list))
+ return -ENODEV;
+
+ list_del_rcu(&trigger->list);
+
+ trace_event_trigger_enable_disable(file, 0);
+ update_cond_flag(file);
return 0;
}
static inline int __enable_trace_kprobe(struct trace_kprobe *tk,
- struct trace_array *tr)
+ struct trace_event_file *file)
{
int ret = 0;
@@ -494,7 +646,7 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk,
if (trace_kprobe_is_return(tk))
ret = enable_kretprobe(&tk->rp);
else if (trace_kprobe_is_event(tk))
- ret = enable_eprobe(tk->ep, tr);
+ ret = enable_eprobe(tk->ep, file);
else
ret = enable_kprobe(&tk->rp.kp);
}
@@ -502,7 +654,8 @@ static inline int __enable_trace_kprobe(struct trace_kprobe *tk,
return ret;
}
-static void __disable_trace_kprobe(struct trace_probe *tp)
+static void __disable_trace_kprobe(struct trace_probe *tp,
+ struct trace_event_file *file)
{
struct trace_probe *pos;
struct trace_kprobe *tk;
@@ -514,7 +667,7 @@ static void __disable_trace_kprobe(struct trace_probe *tp)
if (trace_kprobe_is_return(tk))
disable_kretprobe(&tk->rp);
else if (trace_kprobe_is_event(tk))
- disable_eprobe(tk->ep);
+ disable_eprobe(tk->ep, file->tr);
else
disable_kprobe(&tk->rp.kp);
}
@@ -552,7 +705,7 @@ static int enable_trace_kprobe(struct trace_event_call *call,
tk = container_of(pos, struct trace_kprobe, tp);
if (trace_kprobe_has_gone(tk))
continue;
- ret = __enable_trace_kprobe(tk, file->tr);
+ ret = __enable_trace_kprobe(tk, file);
if (ret)
break;
enabled = true;
@@ -561,7 +714,7 @@ static int enable_trace_kprobe(struct trace_event_call *call,
if (ret) {
/* Failed to enable one of them. Roll back all */
if (enabled)
- __disable_trace_kprobe(tp);
+ __disable_trace_kprobe(tp, file);
if (file)
trace_probe_remove_file(tp, file);
else
@@ -594,7 +747,7 @@ static int disable_trace_kprobe(struct trace_event_call *call,
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
if (!trace_probe_is_enabled(tp))
- __disable_trace_kprobe(tp);
+ __disable_trace_kprobe(tp, file);
out:
if (file)
@@ -894,7 +1047,7 @@ static int trace_eprobe_tp_find(struct trace_kprobe *tk)
mutex_lock(&event_mutex);
list_for_each_entry(tp_event, &ftrace_events, list) {
- if (!(tp_event->flags & TRACE_EVENT_FL_TRACEPOINT))
+ if (tp_event->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
continue;
if (!tp_event->class->system ||
strcmp(tk->ep->event_system, tp_event->class->system))
@@ -907,7 +1060,7 @@ static int trace_eprobe_tp_find(struct trace_kprobe *tk)
ret = -ENODEV;
break;
}
- tk->ep->tp = tp_event;
+ tk->ep->event = tp_event;
ret = 0;
break;
}
@@ -922,7 +1075,7 @@ static int trace_eprobe_tp_arg_find(struct trace_kprobe *tk, int i)
struct ftrace_event_field *field;
struct list_head *head;
- head = trace_get_fields(tk->ep->tp);
+ head = trace_get_fields(tk->ep->event);
list_for_each_entry(field, head, link) {
if (!strcmp(parg->code->data, field->name)) {
kfree(parg->code->data);
@@ -941,6 +1094,7 @@ static int __trace_eprobe_create(int argc, const char *argv[])
unsigned int flags = TPARG_FL_KERNEL | TPARG_FL_TPOINT;
const char *sys_event = NULL, *sys_name = NULL;
struct trace_kprobe *tk = NULL;
+ struct trace_event_call *call;
char buf1[MAX_EVENT_NAME_LEN];
char buf2[MAX_EVENT_NAME_LEN];
char *tmp = NULL;
@@ -950,7 +1104,7 @@ static int __trace_eprobe_create(int argc, const char *argv[])
if (argc < 2)
return -ECANCELED;
- trace_probe_log_init("trace_kprobe", argc, argv);
+ trace_probe_log_init("event_probe", argc, argv);
event = strchr(&argv[0][1], ':');
if (event) {
@@ -1007,19 +1161,25 @@ static int __trace_eprobe_create(int argc, const char *argv[])
ret = traceprobe_set_print_fmt(&tk->tp, false);
if (ret < 0)
goto error;
+
+ mutex_lock(&event_mutex);
ret = register_kprobe_event(tk);
if (ret)
- goto error;
+ goto out_unlock;
- ret = dyn_event_add(&tk->devent);
- if (ret)
- goto error;
+ /* Reassign to a EPROBE */
+ call = trace_probe_event_call(&tk->tp);
+ call->flags = TRACE_EVENT_FL_EPROBE;
+ ret = dyn_event_add(&tk->devent);
+out_unlock:
+ mutex_unlock(&event_mutex);
return ret;
parse_error:
ret = -EINVAL;
error:
+ free_trace_kprobe(tk);
return ret;
}
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 535e1f20519b..2c7988d5698f 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -997,8 +997,8 @@ void trace_event_probe_cleanup(struct keventprobe *ep)
{
kfree(ep->event_name);
kfree(ep->event_system);
- if (ep->tp)
- module_put(ep->tp->mod);
+ if (ep->event)
+ module_put(ep->event->mod);
kfree(ep);
}
--
2.30.2
|