performance counters: x86 support

Implement performance counters for x86 Intel CPUs.

It's simplified right now: the PERFMON CPU feature is assumed,
which is available in Core2 and later Intel CPUs.

The design is flexible to be extended to more CPU types as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 256b00b61892..3c14ed07dc4e 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -823,7 +823,8 @@ ia32_sys_call_table:
         .quad compat_sys_signalfd4
         .quad sys_eventfd2
         .quad sys_epoll_create1
-        .quad sys_dup3                  /* 330 */
+        .quad sys_dup3                          /* 330 */
         .quad sys_pipe2
         .quad sys_inotify_init1
+        .quad sys_perf_counter_open
 ia32_syscall_end: