MIPS: add support for software performance events

Software events are required as part of the measurable stuff by the
Linux performance counter subsystem. Here is the list of events added by
this patch:
PERF_COUNT_SW_PAGE_FAULTS
PERF_COUNT_SW_PAGE_FAULTS_MIN
PERF_COUNT_SW_PAGE_FAULTS_MAJ
PERF_COUNT_SW_ALIGNMENT_FAULTS
PERF_COUNT_SW_EMULATION_FAULTS

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
To: linux-mips@linux-mips.org
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@elte.hu
Cc: acme@redhat.com
Cc: jamie.iles@picochip.com
Acked-by: David Daney <ddaney@caviumnetworks.com>
Reviewed-by: Matt Fleming <matt@console-pimps.org>
Patchwork: https://patchwork.linux-mips.org/patch/1686/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 15 insertions, 3 deletions

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index d053bf4759e4..8d79b8774b30 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -29,6 +29,7 @@
 #include <linux/notifier.h>
 #include <linux/kdb.h>
 #include <linux/irq.h>
+#include <linux/perf_event.h>
 
 #include <asm/bootinfo.h>
 #include <asm/branch.h>
@@ -576,10 +577,16 @@ static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode)
  */
 static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
 {
-        if ((opcode & OPCODE) == LL)
+        if ((opcode & OPCODE) == LL) {
+                perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
+                                1, 0, regs, 0);
                 return simulate_ll(regs, opcode);
-        if ((opcode & OPCODE) == SC)
+        }
+        if ((opcode & OPCODE) == SC) {
+                perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
+                                1, 0, regs, 0);
                 return simulate_sc(regs, opcode);
+        }
 
         return -1;                      /* Must be something else ... */
 }
@@ -595,6 +602,8 @@ static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode)
         if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
                 int rd = (opcode & RD) >> 11;
                 int rt = (opcode & RT) >> 16;
+                perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
+                                1, 0, regs, 0);
                 switch (rd) {
                 case 0:         /* CPU number */
                         regs->regs[rt] = smp_processor_id();
@@ -630,8 +639,11 @@ static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode)
 
 static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
 {
-        if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC)
+        if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) {
+                perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
+                                1, 0, regs, 0);
                 return 0;
+        }
 
         return -1;                      /* Must be something else ... */
 }