Use rseq for cpu_id in libringbuffer

[lttng-ust.git] / libringbuffer / frontend_api.h

diff --git a/libringbuffer/frontend_api.h b/libringbuffer/frontend_api.h
index 140159739feebc954f68d39b33806e3778f4ca01..19fc09e9ae5f29d779a78c737e08e8530c795ae4 100644 (file)
--- a/libringbuffer/frontend_api.h
+++ b/libringbuffer/frontend_api.h
@@ -34,8 +34,14 @@
 #include <urcu-bp.h>
 #include <urcu/compiler.h>
 
+static inline
+int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *config)
+{
+       return lttng_ust_get_cpu();
+}
+
 /**
- * lib_ring_buffer_get_cpu - Precedes ring buffer reserve/commit.
+ * lib_ring_buffer_begin - Precedes ring buffer reserve/commit.
  *
  * Keeps a ring buffer nesting count as supplementary safety net to
  * ensure tracer client code will never trigger an endless recursion.
@@ -49,11 +55,10 @@
  * section.
  */
 static inline
-int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *config)
+int lib_ring_buffer_begin(const struct lttng_ust_lib_ring_buffer_config *config)
 {
-       int cpu, nesting;
+       int nesting;
 
-       cpu = lttng_ust_get_cpu();
        nesting = ++URCU_TLS(lib_ring_buffer_nesting);
        cmm_barrier();
 
@@ -61,15 +66,15 @@ int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *confi
                WARN_ON_ONCE(1);
                URCU_TLS(lib_ring_buffer_nesting)--;
                return -EPERM;
-       } else
-               return cpu;
+       }
+       return 0;
 }
 
 /**
- * lib_ring_buffer_put_cpu - Follows ring buffer reserve/commit.
+ * lib_ring_buffer_end - Follows ring buffer reserve/commit.
  */
 static inline
-void lib_ring_buffer_put_cpu(const struct lttng_ust_lib_ring_buffer_config *config)
+void lib_ring_buffer_end(const struct lttng_ust_lib_ring_buffer_config *config)
 {
        cmm_barrier();
        URCU_TLS(lib_ring_buffer_nesting)--;            /* TLS */