tracing: Make syscall events suitable for multiple buffers

Currently the syscall events record into the global buffer. But if
multiple buffers are in place, then we need to have syscall events
record in the proper buffers.

By adding descriptors to pass to the syscall event functions, the
syscall events can now record into the buffers that have been assigned
to them (one event may be applied to mulitple buffers).

This will allow tracing high volume syscalls along with seldom occurring
syscalls without losing the seldom syscall events.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 15ccd7cd1560..68cad7a9e089 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -13,6 +13,11 @@
 #include <linux/trace_seq.h>
 #include <linux/ftrace_event.h>
 
+#ifdef CONFIG_FTRACE_SYSCALLS
+#include <asm/unistd.h>         /* For NR_SYSCALLS           */
+#include <asm/syscall.h>        /* some archs define it here */
+#endif
+
 enum trace_type {
         __TRACE_FIRST_TYPE = 0,
 
@@ -173,6 +178,12 @@ struct trace_array {
         int                     cpu;
         int                     buffer_disabled;
         struct trace_cpu        trace_cpu;      /* place holder */
+#ifdef CONFIG_FTRACE_SYSCALLS
+        int                     sys_refcount_enter;
+        int                     sys_refcount_exit;
+        DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
+        DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
+#endif
         int                     stop_count;
         int                     clock_id;
         struct tracer           *current_trace;