ARM: 7524/1: support syscall tracing

As specified by ftrace-design.txt, TIF_SYSCALL_TRACEPOINT was
added, as well as NR_syscalls in asm/unistd.h.  Additionally,
__sys_trace was modified to call trace_sys_enter and
trace_sys_exit when appropriate.

Tests #2 - #4 of "perf test" now complete successfully.

Signed-off-by: Steven Walter <stevenrwalter@gmail.com>
Signed-off-by: Wade Farnsworth <wade_farnsworth@mentor.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 3e0fc5f..c382d3c 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -30,6 +30,9 @@
 #include <asm/pgtable.h>
 #include <asm/traps.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
 #define REG_PC	15
 #define REG_PSR	16
 /*
@@ -918,11 +921,11 @@
 {
 	unsigned long ip;
 
+	current_thread_info()->syscall = scno;
+
 	if (!test_thread_flag(TIF_SYSCALL_TRACE))
 		return scno;
 
-	current_thread_info()->syscall = scno;
-
 	/*
 	 * IP is used to denote syscall entry/exit:
 	 * IP = 0 -> entry, =1 -> exit
@@ -942,6 +945,8 @@
 asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
 {
 	int ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_ENTER);
+	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+		trace_sys_enter(regs, ret);
 	audit_syscall_entry(AUDIT_ARCH_ARM, scno, regs->ARM_r0, regs->ARM_r1,
 			    regs->ARM_r2, regs->ARM_r3);
 	return ret;
@@ -950,6 +955,8 @@
 asmlinkage int syscall_trace_exit(struct pt_regs *regs, int scno)
 {
 	int ret = ptrace_syscall_trace(regs, scno, PTRACE_SYSCALL_EXIT);
+	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+		trace_sys_exit(regs, ret);
 	audit_syscall_exit(regs);
 	return ret;
 }