tile: support TIF_SYSCALL_TRACEPOINT; select HAVE_SYSCALL_TRACEPOINTS

This patch adds support for the TIF_SYSCALL_TRACEPOINT on the tile
architecture. Basically, it calls the appropriate tracepoints on syscall
entry and exit.

Signed-off-by: Simon Marchi <simon.marchi@polymtl.ca>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

4 files changed, 33 insertions, 7 deletions

diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index e911ef638b77..0e500d90c2a0 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -23,6 +23,7 @@ config TILE
         select GENERIC_CLOCKEVENTS
         select MODULES_USE_ELF_RELA
         select HAVE_ARCH_TRACEHOOK
+        select HAVE_SYSCALL_TRACEPOINTS
 
 # FIXME: investigate whether we need/want these options.
 #       select HAVE_IOREMAP_PROT
diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h
index e9c670d7a7fe..c96331eb5771 100644
--- a/arch/tile/include/asm/thread_info.h
+++ b/arch/tile/include/asm/thread_info.h
@@ -124,6 +124,7 @@ extern void _cpu_idle(void);
 #define TIF_SECCOMP             6       /* secure computing */
 #define TIF_MEMDIE              7       /* OOM killer at work */
 #define TIF_NOTIFY_RESUME       8       /* callback before returning to user */
+#define TIF_SYSCALL_TRACEPOINT  9       /* syscall tracepoint instrumentation */
 
 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
@@ -134,12 +135,19 @@ extern void _cpu_idle(void);
 #define _TIF_SECCOMP            (1<<TIF_SECCOMP)
 #define _TIF_MEMDIE             (1<<TIF_MEMDIE)
 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
+#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
 
 /* Work to do on any return to user space. */
 #define _TIF_ALLWORK_MASK \
   (_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SINGLESTEP|\
    _TIF_ASYNC_TLB|_TIF_NOTIFY_RESUME)
 
+/* Work to do at syscall entry. */
+#define _TIF_SYSCALL_ENTRY_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
+
+/* Work to do at syscall exit. */
+#define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
+
 /*
  * Thread-synchronous status.
  *
diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S
index 21991f72eba3..85d483957027 100644
--- a/arch/tile/kernel/intvec_64.S
+++ b/arch/tile/kernel/intvec_64.S
@@ -1000,8 +1000,11 @@ handle_syscall:
 
         /* Trace syscalls, if requested. */
         addi    r31, r31, THREAD_INFO_FLAGS_OFFSET
-        ld      r30, r31
-        andi    r30, r30, _TIF_SYSCALL_TRACE
+        {
+         ld     r30, r31
+         moveli r32, _TIF_SYSCALL_ENTRY_WORK
+        }
+        and     r30, r30, r32
         {
          addi   r30, r31, THREAD_INFO_STATUS_OFFSET - THREAD_INFO_FLAGS_OFFSET
          beqzt  r30, .Lrestore_syscall_regs
@@ -1074,8 +1077,11 @@ handle_syscall:
         FEEDBACK_REENTER(handle_syscall)
 
         /* Do syscall trace again, if requested. */
-        ld      r30, r31
-        andi    r0, r30, _TIF_SYSCALL_TRACE
+        {
+         ld      r30, r31
+         moveli  r32, _TIF_SYSCALL_EXIT_WORK
+        }
+        and      r0, r30, r32
         {
          andi    r0, r30, _TIF_SINGLESTEP
          beqzt   r0, 1f
diff --git a/arch/tile/kernel/ptrace.c b/arch/tile/kernel/ptrace.c
index 0ab8b76baddc..363b2dd20f99 100644
--- a/arch/tile/kernel/ptrace.c
+++ b/arch/tile/kernel/ptrace.c
@@ -25,6 +25,9 @@
 #include <asm/traps.h>
 #include <arch/chip.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
 void user_enable_single_step(struct task_struct *child)
 {
         set_tsk_thread_flag(child, TIF_SINGLESTEP);
@@ -249,16 +252,24 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 
 int do_syscall_trace_enter(struct pt_regs *regs)
 {
-        if (tracehook_report_syscall_entry(regs)) {
-                regs->regs[TREG_SYSCALL_NR] = -1;
+        if (test_thread_flag(TIF_SYSCALL_TRACE)) {
+                if (tracehook_report_syscall_entry(regs))
+                        regs->regs[TREG_SYSCALL_NR] = -1;
         }
 
+        if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+                trace_sys_enter(regs, regs->regs[TREG_SYSCALL_NR]);
+
         return regs->regs[TREG_SYSCALL_NR];
 }
 
 void do_syscall_trace_exit(struct pt_regs *regs)
 {
-        tracehook_report_syscall_exit(regs, 0);
+        if (test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall_exit(regs, 0);
+
+        if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+                trace_sys_exit(regs, regs->regs[TREG_SYSCALL_NR]);
 }
 
 void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)