1 files changed, 96 insertions, 90 deletions

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 4e332b9..4d6d711 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -1,5 +1,6 @@
 #include <trace/syscall.h>
 #include <trace/events/syscalls.h>
+#include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/ftrace.h>
 #include <linux/perf_event.h>
@@ -143,70 +144,65 @@ extern char *__bad_type_size(void);
 		#type, #name, offsetof(typeof(trace), name),		\
 		sizeof(trace.name), is_signed_type(type)
 
-int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
+static
+int  __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
 {
 	int i;
-	int ret;
-	struct syscall_metadata *entry = call->data;
-	struct syscall_trace_enter trace;
-	int offset = offsetof(struct syscall_trace_enter, args);
+	int pos = 0;
 
-	ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
-			       "\tsigned:%u;\n",
-			       SYSCALL_FIELD(int, nr));
-	if (!ret)
-		return 0;
+	/* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
 
+	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
 	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;"
-				       "\tsigned:%u;\n", offset,
-				       sizeof(unsigned long),
-				       is_signed_type(unsigned long));
-		if (!ret)
-			return 0;
-		offset += sizeof(unsigned long);
+		pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
+				entry->args[i], sizeof(unsigned long),
+				i == entry->nb_args - 1 ? "" : ", ");
 	}
+	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
 
-	trace_seq_puts(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;
+		pos += snprintf(buf + pos, LEN_OR_ZERO,
+				", ((unsigned long)(REC->%s))", entry->args[i]);
 	}
-	trace_seq_putc(s, '"');
 
-	for (i = 0; i < entry->nb_args; i++) {
-		ret = trace_seq_printf(s, ", ((unsigned long)(REC->%s))",
-				       entry->args[i]);
-		if (!ret)
-			return 0;
-	}
+#undef LEN_OR_ZERO
 
-	return trace_seq_putc(s, '\n');
+	/* return the length of print_fmt */
+	return pos;
 }
 
-int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
+static int set_syscall_print_fmt(struct ftrace_event_call *call)
 {
-	int ret;
-	struct syscall_trace_exit trace;
+	char *print_fmt;
+	int len;
+	struct syscall_metadata *entry = call->data;
 
-	ret = trace_seq_printf(s,
-			       "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
-			       "\tsigned:%u;\n"
-			       "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
-			       "\tsigned:%u;\n",
-			       SYSCALL_FIELD(int, nr),
-			       SYSCALL_FIELD(long, ret));
-	if (!ret)
+	if (entry->enter_event != call) {
+		call->print_fmt = "\"0x%lx\", REC->ret";
 		return 0;
+	}
 
-	return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
+	/* First: called with 0 length to calculate the needed length */
+	len = __set_enter_print_fmt(entry, NULL, 0);
+
+	print_fmt = kmalloc(len + 1, GFP_KERNEL);
+	if (!print_fmt)
+		return -ENOMEM;
+
+	/* Second: actually write the @print_fmt */
+	__set_enter_print_fmt(entry, print_fmt, len + 1);
+	call->print_fmt = print_fmt;
+
+	return 0;
+}
+
+static void free_syscall_print_fmt(struct ftrace_event_call *call)
+{
+	struct syscall_metadata *entry = call->data;
+
+	if (entry->enter_event == call)
+		kfree(call->print_fmt);
 }
 
 int syscall_enter_define_fields(struct ftrace_event_call *call)
@@ -386,12 +382,22 @@ int init_syscall_trace(struct ftrace_event_call *call)
 {
 	int id;
 
-	id = register_ftrace_event(call->event);
-	if (!id)
-		return -ENODEV;
-	call->id = id;
-	INIT_LIST_HEAD(&call->fields);
-	return 0;
+	if (set_syscall_print_fmt(call) < 0)
+		return -ENOMEM;
+
+	id = trace_event_raw_init(call);
+
+	if (id < 0) {
+		free_syscall_print_fmt(call);
+		return id;
+	}
+
+	return id;
+}
+
+unsigned long __init arch_syscall_addr(int nr)
+{
+	return (unsigned long)sys_call_table[nr];
 }
 
 int __init init_ftrace_syscalls(void)
@@ -423,12 +429,12 @@ core_initcall(init_ftrace_syscalls);
 
 #ifdef CONFIG_PERF_EVENTS
 
-static DECLARE_BITMAP(enabled_prof_enter_syscalls, NR_syscalls);
-static DECLARE_BITMAP(enabled_prof_exit_syscalls, NR_syscalls);
-static int sys_prof_refcount_enter;
-static int sys_prof_refcount_exit;
+static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
+static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
+static int sys_perf_refcount_enter;
+static int sys_perf_refcount_exit;
 
-static void prof_syscall_enter(struct pt_regs *regs, long id)
+static void perf_syscall_enter(struct pt_regs *regs, long id)
 {
 	struct syscall_metadata *sys_data;
 	struct syscall_trace_enter *rec;
@@ -438,7 +444,7 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
 	int size;
 
 	syscall_nr = syscall_get_nr(current, regs);
-	if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
+	if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
 		return;
 
 	sys_data = syscall_nr_to_meta(syscall_nr);
@@ -450,11 +456,11 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
 	size = ALIGN(size + sizeof(u32), sizeof(u64));
 	size -= sizeof(u32);
 
-	if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
-		      "profile buffer not large enough"))
+	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
+		      "perf buffer not large enough"))
 		return;
 
-	rec = (struct syscall_trace_enter *)ftrace_perf_buf_prepare(size,
+	rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
 				sys_data->enter_event->id, &rctx, &flags);
 	if (!rec)
 		return;
@@ -462,10 +468,10 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
 	rec->nr = syscall_nr;
 	syscall_get_arguments(current, regs, 0, sys_data->nb_args,
 			       (unsigned long *)&rec->args);
-	ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
+	perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs);
 }
 
-int prof_sysenter_enable(struct ftrace_event_call *call)
+int perf_sysenter_enable(struct ftrace_event_call *call)
 {
 	int ret = 0;
 	int num;
@@ -473,34 +479,34 @@ int prof_sysenter_enable(struct ftrace_event_call *call)
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
 
 	mutex_lock(&syscall_trace_lock);
-	if (!sys_prof_refcount_enter)
-		ret = register_trace_sys_enter(prof_syscall_enter);
+	if (!sys_perf_refcount_enter)
+		ret = register_trace_sys_enter(perf_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++;
+		set_bit(num, enabled_perf_enter_syscalls);
+		sys_perf_refcount_enter++;
 	}
 	mutex_unlock(&syscall_trace_lock);
 	return ret;
 }
 
-void prof_sysenter_disable(struct ftrace_event_call *call)
+void perf_sysenter_disable(struct ftrace_event_call *call)
 {
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
 
 	mutex_lock(&syscall_trace_lock);
-	sys_prof_refcount_enter--;
-	clear_bit(num, enabled_prof_enter_syscalls);
-	if (!sys_prof_refcount_enter)
-		unregister_trace_sys_enter(prof_syscall_enter);
+	sys_perf_refcount_enter--;
+	clear_bit(num, enabled_perf_enter_syscalls);
+	if (!sys_perf_refcount_enter)
+		unregister_trace_sys_enter(perf_syscall_enter);
 	mutex_unlock(&syscall_trace_lock);
 }
 
-static void prof_syscall_exit(struct pt_regs *regs, long ret)
+static void perf_syscall_exit(struct pt_regs *regs, long ret)
 {
 	struct syscall_metadata *sys_data;
 	struct syscall_trace_exit *rec;
@@ -510,7 +516,7 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
 	int size;
 
 	syscall_nr = syscall_get_nr(current, regs);
-	if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
+	if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
 		return;
 
 	sys_data = syscall_nr_to_meta(syscall_nr);
@@ -525,11 +531,11 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
 	 * Impossible, but be paranoid with the future
 	 * How to put this check outside runtime?
 	 */
-	if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
-		"exit event has grown above profile buffer size"))
+	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
+		"exit event has grown above perf buffer size"))
 		return;
 
-	rec = (struct syscall_trace_exit *)ftrace_perf_buf_prepare(size,
+	rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
 				sys_data->exit_event->id, &rctx, &flags);
 	if (!rec)
 		return;
@@ -537,10 +543,10 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
 	rec->nr = syscall_nr;
 	rec->ret = syscall_get_return_value(current, regs);
 
-	ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
+	perf_trace_buf_submit(rec, size, rctx, 0, 1, flags, regs);
 }
 
-int prof_sysexit_enable(struct ftrace_event_call *call)
+int perf_sysexit_enable(struct ftrace_event_call *call)
 {
 	int ret = 0;
 	int num;
@@ -548,30 +554,30 @@ int prof_sysexit_enable(struct ftrace_event_call *call)
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
 
 	mutex_lock(&syscall_trace_lock);
-	if (!sys_prof_refcount_exit)
-		ret = register_trace_sys_exit(prof_syscall_exit);
+	if (!sys_perf_refcount_exit)
+		ret = register_trace_sys_exit(perf_syscall_exit);
 	if (ret) {
 		pr_info("event trace: Could not activate"
-				"syscall entry trace point");
+				"syscall exit trace point");
 	} else {
-		set_bit(num, enabled_prof_exit_syscalls);
-		sys_prof_refcount_exit++;
+		set_bit(num, enabled_perf_exit_syscalls);
+		sys_perf_refcount_exit++;
 	}
 	mutex_unlock(&syscall_trace_lock);
 	return ret;
 }
 
-void prof_sysexit_disable(struct ftrace_event_call *call)
+void perf_sysexit_disable(struct ftrace_event_call *call)
 {
 	int num;
 
 	num = ((struct syscall_metadata *)call->data)->syscall_nr;
 
 	mutex_lock(&syscall_trace_lock);
-	sys_prof_refcount_exit--;
-	clear_bit(num, enabled_prof_exit_syscalls);
-	if (!sys_prof_refcount_exit)
-		unregister_trace_sys_exit(prof_syscall_exit);
+	sys_perf_refcount_exit--;
+	clear_bit(num, enabled_perf_exit_syscalls);
+	if (!sys_perf_refcount_exit)
+		unregister_trace_sys_exit(perf_syscall_exit);
 	mutex_unlock(&syscall_trace_lock);
 }