Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core

arch/s390/kernel/ftrace.c

@@ -220,6 +220,29 @@ struct syscall_metadata *syscall_nr_to_meta(int nr)
 	return syscalls_metadata[nr];
 }
 
+int syscall_name_to_nr(char *name)
+{
+	int i;
+
+	if (!syscalls_metadata)
+		return -1;
+	for (i = 0; i < NR_syscalls; i++)
+		if (syscalls_metadata[i])
+			if (!strcmp(syscalls_metadata[i]->name, name))
+				return i;
+	return -1;
+}
+
+void set_syscall_enter_id(int num, int id)
+{
+	syscalls_metadata[num]->enter_id = id;
+}
+
+void set_syscall_exit_id(int num, int id)
+{
+	syscalls_metadata[num]->exit_id = id;
+}
+
 static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
 {
 	struct syscall_metadata *start;
@@ -237,24 +260,19 @@ static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
 	return NULL;
 }
 
-void arch_init_ftrace_syscalls(void)
+static int __init arch_init_ftrace_syscalls(void)
 {
 	struct syscall_metadata *meta;
 	int i;
-	static atomic_t refs;
-
-	if (atomic_inc_return(&refs) != 1)
-		goto out;
 	syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) * NR_syscalls,
 				    GFP_KERNEL);
 	if (!syscalls_metadata)
-		goto out;
+		return -ENOMEM;
 	for (i = 0; i < NR_syscalls; i++) {
 		meta = find_syscall_meta((unsigned long)sys_call_table[i]);
 		syscalls_metadata[i] = meta;
 	}
-	return;
-out:
-	atomic_dec(&refs);
+	return 0;
 }
+arch_initcall(arch_init_ftrace_syscalls);
 #endif

arch/x86/include/asm/ftrace.h

@@ -28,13 +28,6 @@
 
 #endif
 
-/* FIXME: I don't want to stay hardcoded */
-#ifdef CONFIG_X86_64
-# define FTRACE_SYSCALL_MAX     299
-#else
-# define FTRACE_SYSCALL_MAX     337
-#endif
-
 #ifdef CONFIG_FUNCTION_TRACER
 #define MCOUNT_ADDR		((long)(mcount))
 #define MCOUNT_INSN_SIZE	5 /* sizeof mcount call */

arch/x86/include/asm/unistd_32.h

@@ -345,6 +345,8 @@
 
 #ifdef __KERNEL__
 
+#define NR_syscalls 337
+
 #define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_OLD_READDIR
 #define __ARCH_WANT_OLD_STAT

arch/x86/include/asm/unistd_64.h

@@ -688,6 +688,12 @@ __SYSCALL(__NR_perf_counter_open, sys_perf_counter_open)
 #endif	/* __NO_STUBS */
 
 #ifdef __KERNEL__
+
+#ifndef COMPILE_OFFSETS
+#include <asm/asm-offsets.h>
+#define NR_syscalls (__NR_syscall_max + 1)
+#endif
+
 /*
  * "Conditional" syscalls
  *

arch/x86/kernel/asm-offsets_64.c

@@ -3,6 +3,7 @@
  * This code generates raw asm output which is post-processed to extract
  * and format the required data.
  */
+#define COMPILE_OFFSETS
 
 #include <linux/crypto.h>
 #include <linux/sched.h> 

arch/x86/kernel/ftrace.c

@@ -494,7 +494,7 @@ static struct syscall_metadata *find_syscall_meta(unsigned long *syscall)
 
 struct syscall_metadata *syscall_nr_to_meta(int nr)
 {
-	if (!syscalls_metadata || nr >= FTRACE_SYSCALL_MAX || nr < 0)
+	if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
 		return NULL;
 
 	return syscalls_metadata[nr];
@@ -507,7 +507,7 @@ int syscall_name_to_nr(char *name)
 	if (!syscalls_metadata)
 		return -1;
 
-	for (i = 0; i < FTRACE_SYSCALL_MAX; i++) {
+	for (i = 0; i < NR_syscalls; i++) {
 		if (syscalls_metadata[i]) {
 			if (!strcmp(syscalls_metadata[i]->name, name))
 				return i;
@@ -533,13 +533,13 @@ static int __init arch_init_ftrace_syscalls(void)
 	unsigned long **psys_syscall_table = &sys_call_table;
 
 	syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
-					FTRACE_SYSCALL_MAX, GFP_KERNEL);
+					NR_syscalls, GFP_KERNEL);
 	if (!syscalls_metadata) {
 		WARN_ON(1);
 		return -ENOMEM;
 	}
 
-	for (i = 0; i < FTRACE_SYSCALL_MAX; i++) {
+	for (i = 0; i < NR_syscalls; i++) {
 		meta = find_syscall_meta(psys_syscall_table[i]);
 		syscalls_metadata[i] = meta;
 	}

kernel/trace/trace_syscalls.c

@@ -11,8 +11,8 @@
 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);
+static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
+static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
 
 enum print_line_t
 print_syscall_enter(struct trace_iterator *iter, int flags)
@@ -227,6 +227,8 @@ void ftrace_syscall_enter(struct pt_regs *regs, long id)
 	int syscall_nr;
 
 	syscall_nr = syscall_get_nr(current, regs);
+	if (syscall_nr < 0)
+		return;
 	if (!test_bit(syscall_nr, enabled_enter_syscalls))
 		return;
 
@@ -257,6 +259,8 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret)
 	int syscall_nr;
 
 	syscall_nr = syscall_get_nr(current, regs);
+	if (syscall_nr < 0)
+		return;
 	if (!test_bit(syscall_nr, enabled_exit_syscalls))
 		return;
 
@@ -285,7 +289,7 @@ int reg_event_syscall_enter(void *ptr)
 
 	name = (char *)ptr;
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return -ENOSYS;
 	mutex_lock(&syscall_trace_lock);
 	if (!sys_refcount_enter)
@@ -308,7 +312,7 @@ void unreg_event_syscall_enter(void *ptr)
 
 	name = (char *)ptr;
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return;
 	mutex_lock(&syscall_trace_lock);
 	sys_refcount_enter--;
@@ -326,7 +330,7 @@ int reg_event_syscall_exit(void *ptr)
 
 	name = (char *)ptr;
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return -ENOSYS;
 	mutex_lock(&syscall_trace_lock);
 	if (!sys_refcount_exit)
@@ -349,7 +353,7 @@ void unreg_event_syscall_exit(void *ptr)
 
 	name = (char *)ptr;
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return;
 	mutex_lock(&syscall_trace_lock);
 	sys_refcount_exit--;
@@ -369,8 +373,8 @@ struct trace_event event_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 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;
 
@@ -416,7 +420,7 @@ int reg_prof_syscall_enter(char *name)
 	int num;
 
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return -ENOSYS;
 
 	mutex_lock(&syscall_trace_lock);
@@ -438,7 +442,7 @@ void unreg_prof_syscall_enter(char *name)
 	int num;
 
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return;
 
 	mutex_lock(&syscall_trace_lock);
@@ -477,7 +481,7 @@ int reg_prof_syscall_exit(char *name)
 	int num;
 
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return -ENOSYS;
 
 	mutex_lock(&syscall_trace_lock);
@@ -499,7 +503,7 @@ void unreg_prof_syscall_exit(char *name)
 	int num;
 
 	num = syscall_name_to_nr(name);
-	if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+	if (num < 0 || num >= NR_syscalls)
 		return;
 
 	mutex_lock(&syscall_trace_lock);

kernel/tracepoint.c

@@ -597,7 +597,9 @@ void syscall_regfunc(void)
 	if (!sys_tracepoint_refcount) {
 		read_lock_irqsave(&tasklist_lock, flags);
 		do_each_thread(g, t) {
-			set_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT);
+			/* Skip kernel threads. */
+			if (t->mm)
+				set_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT);
 		} while_each_thread(g, t);
 		read_unlock_irqrestore(&tasklist_lock, flags);
 	}