[net-next-2.6.git] / kernel / trace / trace_syscalls.c

#include <trace/syscall.h>
#include <linux/kernel.h>
#include <linux/ftrace.h>
#include <linux/perf_counter.h>
#include <asm/syscall.h>

#include "trace_output.h"
#include "trace.h"

static DEFINE_MUTEX(syscall_trace_lock);
static int sys_refcount_enter;
static int sys_refcount_exit;
static DECLARE_BITMAP(enabled_enter_syscalls, FTRACE_SYSCALL_MAX);
static DECLARE_BITMAP(enabled_exit_syscalls, FTRACE_SYSCALL_MAX);

enum print_line_t
print_syscall_enter(struct trace_iterator *iter, int flags)
{
	struct trace_seq *s = &iter->seq;
	struct trace_entry *ent = iter->ent;
	struct syscall_trace_enter *trace;
	struct syscall_metadata *entry;
	int i, ret, syscall;

	trace = (typeof(trace))ent;
	syscall = trace->nr;
	entry = syscall_nr_to_meta(syscall);

	if (!entry)
		goto end;

	if (entry->enter_id != ent->type) {
		WARN_ON_ONCE(1);
		goto end;
	}

	ret = trace_seq_printf(s, "%s(", entry->name);
	if (!ret)
		return TRACE_TYPE_PARTIAL_LINE;

	for (i = 0; i < entry->nb_args; i++) {
		/* parameter types */
		if (trace_flags & TRACE_ITER_VERBOSE) {
			ret = trace_seq_printf(s, "%s ", entry->types[i]);
			if (!ret)
				return TRACE_TYPE_PARTIAL_LINE;
		}
		/* parameter values */
		ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i],
				       trace->args[i],
				       i == entry->nb_args - 1 ? ")" : ",");
		if (!ret)
			return TRACE_TYPE_PARTIAL_LINE;
	}

end:
	trace_seq_printf(s, "\n");
	return TRACE_TYPE_HANDLED;
}

enum print_line_t
print_syscall_exit(struct trace_iterator *iter, int flags)
{
	struct trace_seq *s = &iter->seq;
	struct trace_entry *ent = iter->ent;
	struct syscall_trace_exit *trace;
	int syscall;
	struct syscall_metadata *entry;
	int ret;

	trace = (typeof(trace))ent;
	syscall = trace->nr;
	entry = syscall_nr_to_meta(syscall);

	if (!entry) {
		trace_seq_printf(s, "\n");
		return TRACE_TYPE_HANDLED;
	}

	if (entry->exit_id != ent->type) {
		WARN_ON_ONCE(1);
		return TRACE_TYPE_UNHANDLED;
	}

	ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
				trace->ret);
	if (!ret)
		return TRACE_TYPE_PARTIAL_LINE;

	return TRACE_TYPE_HANDLED;
}

extern char *__bad_type_size(void);

#define SYSCALL_FIELD(type, name)					\
	sizeof(type) != sizeof(trace.name) ?				\
		__bad_type_size() :					\
		#type, #name, offsetof(typeof(trace), name), sizeof(trace.name)

int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
{
	int i;
	int nr;
	int ret;
	struct syscall_metadata *entry;
	struct syscall_trace_enter trace;
	int offset = offsetof(struct syscall_trace_enter, args);

	nr = syscall_name_to_nr(call->data);
	entry = syscall_nr_to_meta(nr);

	if (!entry)
		return 0;

	ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
			       SYSCALL_FIELD(int, nr));
	if (!ret)
		return 0;

	for (i = 0; i < entry->nb_args; i++) {
		ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
				        entry->args[i]);
		if (!ret)
			return 0;
		ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
				       sizeof(unsigned long));
		if (!ret)
			return 0;
		offset += sizeof(unsigned long);
	}

	trace_seq_printf(s, "\nprint fmt: \"");
	for (i = 0; i < entry->nb_args; i++) {
		ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
				        sizeof(unsigned long),
					i == entry->nb_args - 1 ? "\", " : ", ");
		if (!ret)
			return 0;
	}

	for (i = 0; i < entry->nb_args; i++) {
		ret = trace_seq_printf(s, "((unsigned long)(REC->%s))%s",
				        entry->args[i],
					i == entry->nb_args - 1 ? "\n" : ", ");
		if (!ret)
			return 0;
	}

	return ret;
}

int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
{
	int ret;
	struct syscall_trace_exit trace;

	ret = trace_seq_printf(s,
			       "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
			       "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
			       SYSCALL_FIELD(int, nr),
			       SYSCALL_FIELD(unsigned long, ret));
	if (!ret)
		return 0;

	return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
}

int syscall_enter_define_fields(struct ftrace_event_call *call)
{
	struct syscall_trace_enter trace;
	struct syscall_metadata *meta;
	int ret;
	int nr;
	int i;
	int offset = offsetof(typeof(trace), args);

	nr = syscall_name_to_nr(call->data);
	meta = syscall_nr_to_meta(nr);

	if (!meta)
		return 0;

	ret = trace_define_common_fields(call);
	if (ret)
		return ret;

	for (i = 0; i < meta->nb_args; i++) {
		ret = trace_define_field(call, meta->types[i],
					 meta->args[i], offset,
					 sizeof(unsigned long), 0);
		offset += sizeof(unsigned long);
	}

	return ret;
}

int syscall_exit_define_fields(struct ftrace_event_call *call)
{
	struct syscall_trace_exit trace;
	int ret;

	ret = trace_define_common_fields(call);
	if (ret)
		return ret;

	ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0);

	return ret;
}

void ftrace_syscall_enter(struct pt_regs *regs, long id)
{
	struct syscall_trace_enter *entry;
	struct syscall_metadata *sys_data;
	struct ring_buffer_event *event;
	int size;
	int syscall_nr;

	syscall_nr = syscall_get_nr(current, regs);
	if (!test_bit(syscall_nr, enabled_enter_syscalls))
		return;

	sys_data = syscall_nr_to_meta(syscall_nr);
	if (!sys_data)
		return;

	size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;

	event = trace_current_buffer_lock_reserve(sys_data->enter_id, size,
							0, 0);
	if (!event)
		return;

	entry = ring_buffer_event_data(event);
	entry->nr = syscall_nr;
	syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);

	if (!filter_current_check_discard(sys_data->enter_event, entry, event))
		trace_current_buffer_unlock_commit(event, 0, 0);
}

void ftrace_syscall_exit(struct pt_regs *regs, long ret)
{
	struct syscall_trace_exit *entry;
	struct syscall_metadata *sys_data;
	struct ring_buffer_event *event;
	int syscall_nr;

	syscall_nr = syscall_get_nr(current, regs);
	if (!test_bit(syscall_nr, enabled_exit_syscalls))
		return;

	sys_data = syscall_nr_to_meta(syscall_nr);
	if (!sys_data)
		return;

	event = trace_current_buffer_lock_reserve(sys_data->exit_id,
				sizeof(*entry), 0, 0);
	if (!event)
		return;

	entry = ring_buffer_event_data(event);
	entry->nr = syscall_nr;
	entry->ret = syscall_get_return_value(current, regs);

	if (!filter_current_check_discard(sys_data->exit_event, entry, event))
		trace_current_buffer_unlock_commit(event, 0, 0);
}

int reg_event_syscall_enter(void *ptr)
{
	int ret = 0;
	int num;
	char *name;

	name = (char *)ptr;
	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return -ENOSYS;
	mutex_lock(&syscall_trace_lock);
	if (!sys_refcount_enter)
		ret = register_trace_syscall_enter(ftrace_syscall_enter);
	if (ret) {
		pr_info("event trace: Could not activate"
				"syscall entry trace point");
	} else {
		set_bit(num, enabled_enter_syscalls);
		sys_refcount_enter++;
	}
	mutex_unlock(&syscall_trace_lock);
	return ret;
}

void unreg_event_syscall_enter(void *ptr)
{
	int num;
	char *name;

	name = (char *)ptr;
	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return;
	mutex_lock(&syscall_trace_lock);
	sys_refcount_enter--;
	clear_bit(num, enabled_enter_syscalls);
	if (!sys_refcount_enter)
		unregister_trace_syscall_enter(ftrace_syscall_enter);
	mutex_unlock(&syscall_trace_lock);
}

int reg_event_syscall_exit(void *ptr)
{
	int ret = 0;
	int num;
	char *name;

	name = (char *)ptr;
	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return -ENOSYS;
	mutex_lock(&syscall_trace_lock);
	if (!sys_refcount_exit)
		ret = register_trace_syscall_exit(ftrace_syscall_exit);
	if (ret) {
		pr_info("event trace: Could not activate"
				"syscall exit trace point");
	} else {
		set_bit(num, enabled_exit_syscalls);
		sys_refcount_exit++;
	}
	mutex_unlock(&syscall_trace_lock);
	return ret;
}

void unreg_event_syscall_exit(void *ptr)
{
	int num;
	char *name;

	name = (char *)ptr;
	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return;
	mutex_lock(&syscall_trace_lock);
	sys_refcount_exit--;
	clear_bit(num, enabled_exit_syscalls);
	if (!sys_refcount_exit)
		unregister_trace_syscall_exit(ftrace_syscall_exit);
	mutex_unlock(&syscall_trace_lock);
}

struct trace_event event_syscall_enter = {
	.trace			= print_syscall_enter,
};

struct trace_event event_syscall_exit = {
	.trace			= print_syscall_exit,
};

#ifdef CONFIG_EVENT_PROFILE

static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX);
static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX);
static int sys_prof_refcount_enter;
static int sys_prof_refcount_exit;

static void prof_syscall_enter(struct pt_regs *regs, long id)
{
	struct syscall_trace_enter *rec;
	struct syscall_metadata *sys_data;
	int syscall_nr;
	int size;

	syscall_nr = syscall_get_nr(current, regs);
	if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
		return;

	sys_data = syscall_nr_to_meta(syscall_nr);
	if (!sys_data)
		return;

	/* get the size after alignment with the u32 buffer size field */
	size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
	size = ALIGN(size + sizeof(u32), sizeof(u64));
	size -= sizeof(u32);

	do {
		char raw_data[size];

		/* zero the dead bytes from align to not leak stack to user */
		*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;

		rec = (struct syscall_trace_enter *) raw_data;
		tracing_generic_entry_update(&rec->ent, 0, 0);
		rec->ent.type = sys_data->enter_id;
		rec->nr = syscall_nr;
		syscall_get_arguments(current, regs, 0, sys_data->nb_args,
				       (unsigned long *)&rec->args);
		perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
	} while(0);
}

int reg_prof_syscall_enter(char *name)
{
	int ret = 0;
	int num;

	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return -ENOSYS;

	mutex_lock(&syscall_trace_lock);
	if (!sys_prof_refcount_enter)
		ret = register_trace_syscall_enter(prof_syscall_enter);
	if (ret) {
		pr_info("event trace: Could not activate"
				"syscall entry trace point");
	} else {
		set_bit(num, enabled_prof_enter_syscalls);
		sys_prof_refcount_enter++;
	}
	mutex_unlock(&syscall_trace_lock);
	return ret;
}

void unreg_prof_syscall_enter(char *name)
{
	int num;

	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return;

	mutex_lock(&syscall_trace_lock);
	sys_prof_refcount_enter--;
	clear_bit(num, enabled_prof_enter_syscalls);
	if (!sys_prof_refcount_enter)
		unregister_trace_syscall_enter(prof_syscall_enter);
	mutex_unlock(&syscall_trace_lock);
}

static void prof_syscall_exit(struct pt_regs *regs, long ret)
{
	struct syscall_metadata *sys_data;
	struct syscall_trace_exit rec;
	int syscall_nr;

	syscall_nr = syscall_get_nr(current, regs);
	if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
		return;

	sys_data = syscall_nr_to_meta(syscall_nr);
	if (!sys_data)
		return;

	tracing_generic_entry_update(&rec.ent, 0, 0);
	rec.ent.type = sys_data->exit_id;
	rec.nr = syscall_nr;
	rec.ret = syscall_get_return_value(current, regs);

	perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
}

int reg_prof_syscall_exit(char *name)
{
	int ret = 0;
	int num;

	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return -ENOSYS;

	mutex_lock(&syscall_trace_lock);
	if (!sys_prof_refcount_exit)
		ret = register_trace_syscall_exit(prof_syscall_exit);
	if (ret) {
		pr_info("event trace: Could not activate"
				"syscall entry trace point");
	} else {
		set_bit(num, enabled_prof_exit_syscalls);
		sys_prof_refcount_exit++;
	}
	mutex_unlock(&syscall_trace_lock);
	return ret;
}

void unreg_prof_syscall_exit(char *name)
{
	int num;

	num = syscall_name_to_nr(name);
	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
		return;

	mutex_lock(&syscall_trace_lock);
	sys_prof_refcount_exit--;
	clear_bit(num, enabled_prof_exit_syscalls);
	if (!sys_prof_refcount_exit)
		unregister_trace_syscall_exit(prof_syscall_exit);
	mutex_unlock(&syscall_trace_lock);
}

#endif
Commit	Line	Data
47788c58	1	#include <trace/syscall.h>
ee08c6ec	2	#include <linux/kernel.h>
fb34a08c	3	#include <linux/ftrace.h>
f4b5ffcc	4	#include <linux/perf_counter.h>
ee08c6ec FW	5	#include <asm/syscall.h>
	6
	7	#include "trace_output.h"
	8	#include "trace.h"
	9
5be71b61	10	static DEFINE_MUTEX(syscall_trace_lock);
fb34a08c JB	11	static int sys_refcount_enter;
	12	static int sys_refcount_exit;
	13	static DECLARE_BITMAP(enabled_enter_syscalls, FTRACE_SYSCALL_MAX);
	14	static DECLARE_BITMAP(enabled_exit_syscalls, FTRACE_SYSCALL_MAX);
ee08c6ec	15
bed1ffca FW	16	enum print_line_t
	17	print_syscall_enter(struct trace_iterator *iter, int flags)
	18	{
	19	struct trace_seq *s = &iter->seq;
	20	struct trace_entry *ent = iter->ent;
	21	struct syscall_trace_enter *trace;
	22	struct syscall_metadata *entry;
	23	int i, ret, syscall;
	24
64c12e04	25	trace = (typeof(trace))ent;
bed1ffca	26	syscall = trace->nr;
bed1ffca	27	entry = syscall_nr_to_meta(syscall);
64c12e04	28
bed1ffca FW	29	if (!entry)
	30	goto end;
	31
64c12e04 JB	32	if (entry->enter_id != ent->type) {
	33	WARN_ON_ONCE(1);
	34	goto end;
	35	}
	36
bed1ffca FW	37	ret = trace_seq_printf(s, "%s(", entry->name);
	38	if (!ret)
	39	return TRACE_TYPE_PARTIAL_LINE;
	40
	41	for (i = 0; i < entry->nb_args; i++) {
	42	/* parameter types */
ba8b3a40	43	if (trace_flags & TRACE_ITER_VERBOSE) {
bed1ffca FW	44	ret = trace_seq_printf(s, "%s ", entry->types[i]);
	45	if (!ret)
	46	return TRACE_TYPE_PARTIAL_LINE;
	47	}
	48	/* parameter values */
	49	ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i],
	50	trace->args[i],
	51	i == entry->nb_args - 1 ? ")" : ",");
	52	if (!ret)
	53	return TRACE_TYPE_PARTIAL_LINE;
	54	}
	55
	56	end:
	57	trace_seq_printf(s, "\n");
	58	return TRACE_TYPE_HANDLED;
	59	}
	60
	61	enum print_line_t
	62	print_syscall_exit(struct trace_iterator *iter, int flags)
	63	{
	64	struct trace_seq *s = &iter->seq;
	65	struct trace_entry *ent = iter->ent;
	66	struct syscall_trace_exit *trace;
	67	int syscall;
	68	struct syscall_metadata *entry;
	69	int ret;
	70
64c12e04	71	trace = (typeof(trace))ent;
bed1ffca	72	syscall = trace->nr;
bed1ffca	73	entry = syscall_nr_to_meta(syscall);
64c12e04	74
bed1ffca FW	75	if (!entry) {
	76	trace_seq_printf(s, "\n");
	77	return TRACE_TYPE_HANDLED;
	78	}
	79
64c12e04 JB	80	if (entry->exit_id != ent->type) {
	81	WARN_ON_ONCE(1);
	82	return TRACE_TYPE_UNHANDLED;
	83	}
	84
bed1ffca FW	85	ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
	86	trace->ret);
	87	if (!ret)
	88	return TRACE_TYPE_PARTIAL_LINE;
	89
	90	return TRACE_TYPE_HANDLED;
	91	}
	92
e6971969 LZ	93	extern char *__bad_type_size(void);
	94
	95	#define SYSCALL_FIELD(type, name) \
	96	sizeof(type) != sizeof(trace.name) ? \
	97	__bad_type_size() : \
	98	#type, #name, offsetof(typeof(trace), name), sizeof(trace.name)
	99
10a5b66f	100	int syscall_enter_format(struct ftrace_event_call call, struct trace_seq s)
dc4ddb4c FW	101	{
	102	int i;
	103	int nr;
e6971969	104	int ret;
dc4ddb4c	105	struct syscall_metadata *entry;
e6971969 LZ	106	struct syscall_trace_enter trace;
e6971969 LZ	107	int offset = offsetof(struct syscall_trace_enter, args);
dc4ddb4c	108
e6971969	109	nr = syscall_name_to_nr(call->data);
dc4ddb4c FW	110	entry = syscall_nr_to_meta(nr);
	111
	112	if (!entry)
e6971969 LZ	113	return 0;
	114
	115	ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
	116	SYSCALL_FIELD(int, nr));
	117	if (!ret)
	118	return 0;
dc4ddb4c FW	119
	120	for (i = 0; i < entry->nb_args; i++) {
	121	ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
	122	entry->args[i]);
	123	if (!ret)
	124	return 0;
e6971969	125	ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
dc4ddb4c FW	126	sizeof(unsigned long));
	127	if (!ret)
	128	return 0;
	129	offset += sizeof(unsigned long);
	130	}
	131
	132	trace_seq_printf(s, "\nprint fmt: \"");
	133	for (i = 0; i < entry->nb_args; i++) {
e6971969	134	ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
dc4ddb4c FW	135	sizeof(unsigned long),
	136	i == entry->nb_args - 1 ? "\", " : ", ");
	137	if (!ret)
	138	return 0;
	139	}
	140
	141	for (i = 0; i < entry->nb_args; i++) {
	142	ret = trace_seq_printf(s, "((unsigned long)(REC->%s))%s",
	143	entry->args[i],
	144	i == entry->nb_args - 1 ? "\n" : ", ");
	145	if (!ret)
	146	return 0;
	147	}
	148
	149	return ret;
	150	}
	151
10a5b66f LZ	152	int syscall_exit_format(struct ftrace_event_call call, struct trace_seq s)
	153	{
	154	int ret;
	155	struct syscall_trace_exit trace;
	156
	157	ret = trace_seq_printf(s,
	158	"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
	159	"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
	160	SYSCALL_FIELD(int, nr),
	161	SYSCALL_FIELD(unsigned long, ret));
	162	if (!ret)
	163	return 0;
	164
	165	return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
	166	}
	167
540b7b8d LZ	168	int syscall_enter_define_fields(struct ftrace_event_call *call)
	169	{
	170	struct syscall_trace_enter trace;
	171	struct syscall_metadata *meta;
	172	int ret;
	173	int nr;
	174	int i;
	175	int offset = offsetof(typeof(trace), args);
	176
	177	nr = syscall_name_to_nr(call->data);
	178	meta = syscall_nr_to_meta(nr);
	179
	180	if (!meta)
	181	return 0;
	182
	183	ret = trace_define_common_fields(call);
	184	if (ret)
	185	return ret;
	186
	187	for (i = 0; i < meta->nb_args; i++) {
	188	ret = trace_define_field(call, meta->types[i],
	189	meta->args[i], offset,
	190	sizeof(unsigned long), 0);
	191	offset += sizeof(unsigned long);
	192	}
	193
	194	return ret;
	195	}
	196
	197	int syscall_exit_define_fields(struct ftrace_event_call *call)
	198	{
	199	struct syscall_trace_exit trace;
	200	int ret;
	201
	202	ret = trace_define_common_fields(call);
	203	if (ret)
	204	return ret;
	205
	206	ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0);
	207
	208	return ret;
	209	}
	210
fb34a08c	211	void ftrace_syscall_enter(struct pt_regs *regs, long id)
ee08c6ec	212	{
bed1ffca FW	213	struct syscall_trace_enter *entry;
	214	struct syscall_metadata *sys_data;
	215	struct ring_buffer_event *event;
	216	int size;
ee08c6ec FW	217	int syscall_nr;
	218
	219	syscall_nr = syscall_get_nr(current, regs);
fb34a08c JB	220	if (!test_bit(syscall_nr, enabled_enter_syscalls))
fb34a08c JB	221	return;
ee08c6ec	222
bed1ffca FW	223	sys_data = syscall_nr_to_meta(syscall_nr);
	224	if (!sys_data)
	225	return;
	226
	227	size = sizeof(entry) + sizeof(unsigned long) sys_data->nb_args;
	228
64c12e04	229	event = trace_current_buffer_lock_reserve(sys_data->enter_id, size,
bed1ffca FW	230	0, 0);
	231	if (!event)
	232	return;
	233
	234	entry = ring_buffer_event_data(event);
	235	entry->nr = syscall_nr;
	236	syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
	237
540b7b8d LZ	238	if (!filter_current_check_discard(sys_data->enter_event, entry, event))
540b7b8d LZ	239	trace_current_buffer_unlock_commit(event, 0, 0);
ee08c6ec FW	240	}
ee08c6ec FW	241
fb34a08c	242	void ftrace_syscall_exit(struct pt_regs *regs, long ret)
ee08c6ec	243	{
bed1ffca FW	244	struct syscall_trace_exit *entry;
	245	struct syscall_metadata *sys_data;
	246	struct ring_buffer_event *event;
ee08c6ec FW	247	int syscall_nr;
	248
	249	syscall_nr = syscall_get_nr(current, regs);
fb34a08c JB	250	if (!test_bit(syscall_nr, enabled_exit_syscalls))
fb34a08c JB	251	return;
ee08c6ec	252
bed1ffca FW	253	sys_data = syscall_nr_to_meta(syscall_nr);
	254	if (!sys_data)
	255	return;
	256
64c12e04	257	event = trace_current_buffer_lock_reserve(sys_data->exit_id,
bed1ffca FW	258	sizeof(*entry), 0, 0);
	259	if (!event)
	260	return;
	261
	262	entry = ring_buffer_event_data(event);
	263	entry->nr = syscall_nr;
	264	entry->ret = syscall_get_return_value(current, regs);
	265
540b7b8d LZ	266	if (!filter_current_check_discard(sys_data->exit_event, entry, event))
540b7b8d LZ	267	trace_current_buffer_unlock_commit(event, 0, 0);
ee08c6ec FW	268	}
ee08c6ec FW	269
fb34a08c	270	int reg_event_syscall_enter(void *ptr)
ee08c6ec	271	{
fb34a08c JB	272	int ret = 0;
	273	int num;
	274	char *name;
	275
	276	name = (char *)ptr;
	277	num = syscall_name_to_nr(name);
	278	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	279	return -ENOSYS;
	280	mutex_lock(&syscall_trace_lock);
	281	if (!sys_refcount_enter)
	282	ret = register_trace_syscall_enter(ftrace_syscall_enter);
	283	if (ret) {
	284	pr_info("event trace: Could not activate"
	285	"syscall entry trace point");
	286	} else {
	287	set_bit(num, enabled_enter_syscalls);
	288	sys_refcount_enter++;
	289	}
	290	mutex_unlock(&syscall_trace_lock);
	291	return ret;
ee08c6ec FW	292	}
ee08c6ec FW	293
fb34a08c	294	void unreg_event_syscall_enter(void *ptr)
ee08c6ec	295	{
fb34a08c JB	296	int num;
fb34a08c JB	297	char *name;
ee08c6ec	298
fb34a08c JB	299	name = (char *)ptr;
	300	num = syscall_name_to_nr(name);
	301	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	302	return;
	303	mutex_lock(&syscall_trace_lock);
	304	sys_refcount_enter--;
	305	clear_bit(num, enabled_enter_syscalls);
	306	if (!sys_refcount_enter)
	307	unregister_trace_syscall_enter(ftrace_syscall_enter);
	308	mutex_unlock(&syscall_trace_lock);
	309	}
ee08c6ec	310
fb34a08c	311	int reg_event_syscall_exit(void *ptr)
ee08c6ec	312	{
fb34a08c JB	313	int ret = 0;
	314	int num;
	315	char *name;
	316
	317	name = (char *)ptr;
	318	num = syscall_name_to_nr(name);
	319	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	320	return -ENOSYS;
	321	mutex_lock(&syscall_trace_lock);
	322	if (!sys_refcount_exit)
	323	ret = register_trace_syscall_exit(ftrace_syscall_exit);
	324	if (ret) {
	325	pr_info("event trace: Could not activate"
	326	"syscall exit trace point");
	327	} else {
	328	set_bit(num, enabled_exit_syscalls);
	329	sys_refcount_exit++;
ee08c6ec	330	}
fb34a08c JB	331	mutex_unlock(&syscall_trace_lock);
	332	return ret;
	333	}
ee08c6ec	334
fb34a08c JB	335	void unreg_event_syscall_exit(void *ptr)
	336	{
	337	int num;
	338	char *name;
ee08c6ec	339
fb34a08c JB	340	name = (char *)ptr;
	341	num = syscall_name_to_nr(name);
	342	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	343	return;
	344	mutex_lock(&syscall_trace_lock);
	345	sys_refcount_exit--;
	346	clear_bit(num, enabled_exit_syscalls);
	347	if (!sys_refcount_exit)
	348	unregister_trace_syscall_exit(ftrace_syscall_exit);
	349	mutex_unlock(&syscall_trace_lock);
ee08c6ec	350	}
fb34a08c JB	351
	352	struct trace_event event_syscall_enter = {
	353	.trace = print_syscall_enter,
fb34a08c JB	354	};
	355
	356	struct trace_event event_syscall_exit = {
	357	.trace = print_syscall_exit,
fb34a08c	358	};
f4b5ffcc JB	359
f4b5ffcc JB	360	#ifdef CONFIG_EVENT_PROFILE
19007a67	361
f4b5ffcc JB	362	static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX);
	363	static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX);
	364	static int sys_prof_refcount_enter;
	365	static int sys_prof_refcount_exit;
	366
	367	static void prof_syscall_enter(struct pt_regs *regs, long id)
	368	{
e6971969	369	struct syscall_trace_enter *rec;
f4b5ffcc JB	370	struct syscall_metadata *sys_data;
f4b5ffcc JB	371	int syscall_nr;
19007a67	372	int size;
f4b5ffcc JB	373
	374	syscall_nr = syscall_get_nr(current, regs);
	375	if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
	376	return;
	377
	378	sys_data = syscall_nr_to_meta(syscall_nr);
	379	if (!sys_data)
	380	return;
	381
19007a67 FW	382	/* get the size after alignment with the u32 buffer size field */
	383	size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
	384	size = ALIGN(size + sizeof(u32), sizeof(u64));
	385	size -= sizeof(u32);
	386
	387	do {
	388	char raw_data[size];
	389
	390	/* zero the dead bytes from align to not leak stack to user */
	391	(u64 )(&raw_data[size - sizeof(u64)]) = 0ULL;
	392
e6971969 LZ	393	rec = (struct syscall_trace_enter *) raw_data;
	394	tracing_generic_entry_update(&rec->ent, 0, 0);
	395	rec->ent.type = sys_data->enter_id;
	396	rec->nr = syscall_nr;
19007a67 FW	397	syscall_get_arguments(current, regs, 0, sys_data->nb_args,
	398	(unsigned long *)&rec->args);
	399	perf_tpcounter_event(sys_data->enter_id, 0, 1, rec, size);
	400	} while(0);
f4b5ffcc JB	401	}
	402
	403	int reg_prof_syscall_enter(char *name)
	404	{
	405	int ret = 0;
	406	int num;
	407
	408	num = syscall_name_to_nr(name);
	409	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	410	return -ENOSYS;
	411
	412	mutex_lock(&syscall_trace_lock);
	413	if (!sys_prof_refcount_enter)
	414	ret = register_trace_syscall_enter(prof_syscall_enter);
	415	if (ret) {
	416	pr_info("event trace: Could not activate"
	417	"syscall entry trace point");
	418	} else {
	419	set_bit(num, enabled_prof_enter_syscalls);
	420	sys_prof_refcount_enter++;
	421	}
	422	mutex_unlock(&syscall_trace_lock);
	423	return ret;
	424	}
	425
	426	void unreg_prof_syscall_enter(char *name)
	427	{
	428	int num;
	429
	430	num = syscall_name_to_nr(name);
	431	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	432	return;
	433
	434	mutex_lock(&syscall_trace_lock);
	435	sys_prof_refcount_enter--;
	436	clear_bit(num, enabled_prof_enter_syscalls);
	437	if (!sys_prof_refcount_enter)
	438	unregister_trace_syscall_enter(prof_syscall_enter);
	439	mutex_unlock(&syscall_trace_lock);
	440	}
	441
	442	static void prof_syscall_exit(struct pt_regs *regs, long ret)
	443	{
	444	struct syscall_metadata *sys_data;
e6971969	445	struct syscall_trace_exit rec;
f4b5ffcc JB	446	int syscall_nr;
	447
	448	syscall_nr = syscall_get_nr(current, regs);
	449	if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
	450	return;
	451
	452	sys_data = syscall_nr_to_meta(syscall_nr);
	453	if (!sys_data)
	454	return;
	455
e6971969 LZ	456	tracing_generic_entry_update(&rec.ent, 0, 0);
	457	rec.ent.type = sys_data->exit_id;
	458	rec.nr = syscall_nr;
19007a67 FW	459	rec.ret = syscall_get_return_value(current, regs);
	460
	461	perf_tpcounter_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
f4b5ffcc JB	462	}
	463
	464	int reg_prof_syscall_exit(char *name)
	465	{
	466	int ret = 0;
	467	int num;
	468
	469	num = syscall_name_to_nr(name);
	470	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	471	return -ENOSYS;
	472
	473	mutex_lock(&syscall_trace_lock);
	474	if (!sys_prof_refcount_exit)
	475	ret = register_trace_syscall_exit(prof_syscall_exit);
	476	if (ret) {
	477	pr_info("event trace: Could not activate"
	478	"syscall entry trace point");
	479	} else {
	480	set_bit(num, enabled_prof_exit_syscalls);
	481	sys_prof_refcount_exit++;
	482	}
	483	mutex_unlock(&syscall_trace_lock);
	484	return ret;
	485	}
	486
	487	void unreg_prof_syscall_exit(char *name)
	488	{
	489	int num;
	490
	491	num = syscall_name_to_nr(name);
	492	if (num < 0 \|\| num >= FTRACE_SYSCALL_MAX)
	493	return;
	494
	495	mutex_lock(&syscall_trace_lock);
	496	sys_prof_refcount_exit--;
	497	clear_bit(num, enabled_prof_exit_syscalls);
	498	if (!sys_prof_refcount_exit)
	499	unregister_trace_syscall_exit(prof_syscall_exit);
	500	mutex_unlock(&syscall_trace_lock);
	501	}
	502
	503	#endif
	504
	505