parisc: split syscall_trace into two halves

Instead of fiddling with gr[20], restructure code to return whether
or not to -ENOSYS. (Also do a bit of fiddling to let them take
pt_regs directly instead of re-computing it.)

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>

1 files changed, 12 insertions, 13 deletions

diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
index 2118ed02e886..08f6d2cbf0e0 100644
--- a/arch/parisc/kernel/ptrace.c
+++ b/arch/parisc/kernel/ptrace.c
@@ -264,20 +264,19 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 }
 #endif
 
+long do_syscall_trace_enter(struct pt_regs *regs)
+{
+        if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+            tracehook_report_syscall_entry(regs))
+                return -1L;
+
+        return regs->gr[20];
+}
 
-void syscall_trace(int why)
+void do_syscall_trace_exit(struct pt_regs *regs)
 {
-        struct pt_regs *regs = &current->thread.regs;
+        int stepping = !!(current->ptrace & (PT_SINGLESTEP|PT_BLOCKSTEP));
 
-        if (!test_thread_flag(TIF_SYSCALL_TRACE))
-                return;
-        /*
-         * Report the system call for tracing.  Entry tracing can
-         * decide to abort the call.  We handle that by setting an
-         * invalid syscall number (-1) to force an ENOSYS error.
-         */
-        if (why)
-                tracehook_report_syscall_exit(regs, 0);
-        else if (tracehook_report_syscall_entry(regs))
-                regs->gr[20] = -1;      /* force ENOSYS */
+        if (stepping || test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall_exit(regs, stepping);
 }