perf counters: implement PERF_COUNT_CPU_CLOCK

Impact: add new perf-counter type

The 'CPU clock' counter counts the amount of CPU clock time that is
elapsing, in nanoseconds. (regardless of how much of it the task is
spending on a CPU executing)

This counter type is a Linux kernel based abstraction, it is available
even if the hardware does not support native hardware performance counters.

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

1 files changed, 6 insertions, 3 deletions

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 27385641ecb6..9a1713a1be27 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -131,7 +131,7 @@ struct perf_counter {
         struct list_head                list_entry;
         struct list_head                sibling_list;
         struct perf_counter             *group_leader;
-        struct hw_perf_counter_ops      *hw_ops;
+        const struct hw_perf_counter_ops *hw_ops;
 
         int                             active;
 #if BITS_PER_LONG == 64
@@ -197,7 +197,7 @@ struct perf_cpu_context {
 extern int perf_max_counters;
 
 #ifdef CONFIG_PERF_COUNTERS
-extern struct hw_perf_counter_ops *
+extern const struct hw_perf_counter_ops *
 hw_perf_counter_init(struct perf_counter *counter);
 
 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
@@ -208,6 +208,9 @@ extern void perf_counter_notify(struct pt_regs *regs);
 extern void perf_counter_print_debug(void);
 extern void hw_perf_restore_ctrl(u64 ctrl);
 extern u64 hw_perf_disable_all(void);
+extern void atomic64_counter_set(struct perf_counter *counter, u64 val64);
+extern u64 atomic64_counter_read(struct perf_counter *counter);
+
 #else
 static inline void
 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
@@ -219,7 +222,7 @@ static inline void perf_counter_init_task(struct task_struct *task)	{ }
 static inline void perf_counter_notify(struct pt_regs *regs)            { }
 static inline void perf_counter_print_debug(void)                       { }
 static inline void hw_perf_restore_ctrl(u64 ctrl)                       { }
-static inline u64 hw_perf_disable_all(void)             { return 0; }
+static inline u64 hw_perf_disable_all(void)                   { return 0; }
 #endif
 
 #endif /* _LINUX_PERF_COUNTER_H */