csky: add page fault perf event support

This patch add support for page fault count, major fault count
and minorfault count. Without this patch page faults are not
sampled for perf event.

Performance counter stats for '/usr/lib/perf-test/callchain_test':
	0      page-faults               #    0.000 K/sec

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>

diff --git a/arch/csky/mm/fault.c b/arch/csky/mm/fault.c
index 5beb25ca1c79804e4bd14402fa1b44a70feff476..aeb9a5f11e00a31238ce2d71c95d300dcb72481b 100644 (file)
--- a/arch/csky/mm/fault.c
+++ b/arch/csky/mm/fault.c
@@ -17,6 +17,7 @@
 #include <linux/vt_kern.h>
 #include <linux/extable.h>
 #include <linux/uaccess.h>
+#include <linux/perf_event.h>
 
 #include <asm/hardirq.h>
 #include <asm/mmu_context.h>
@@ -106,6 +107,8 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
                return;
        }
 #endif
+
+       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
        /*
         * If we're in an interrupt or have no user
         * context, we must not take the fault..
@@ -153,10 +156,15 @@ good_area:
                        goto bad_area;
                BUG();
        }
-       if (fault & VM_FAULT_MAJOR)
+       if (fault & VM_FAULT_MAJOR) {
                tsk->maj_flt++;
-       else
+               perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs,
+                             address);
+       } else {
                tsk->min_flt++;
+               perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs,
+                             address);
+       }
 
        up_read(&mm->mmap_sem);
        return;