gator: Use for_each_kernel_tracepoint in Linux 3.15

Starting with Linux 3.15, unexported tracepoints can't be used
directly. Use for_each_kernel_tracepoint to iterate over all
tracepoints and save off the tracepoints we're interested in.

Signed-off-by: Drew Richardson <drew.richardson@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>

2 files changed, 62 insertions, 1 deletions

diff --git a/driver/gator.h b/driver/gator.h
index 586cd9e..58cb0a2 100644
--- a/driver/gator.h
+++ b/driver/gator.h
@@ -82,13 +82,21 @@ int gatorfs_create_ro_ulong(struct super_block *sb, struct dentry *root,
                 register_trace_##probe_name(probe_##probe_name)
 #       define GATOR_UNREGISTER_TRACE(probe_name) \
                 unregister_trace_##probe_name(probe_##probe_name)
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(3, 15, 0)
 #       define GATOR_DEFINE_PROBE(probe_name, proto) \
                 static void probe_##probe_name(void *data, PARAMS(proto))
 #       define GATOR_REGISTER_TRACE(probe_name) \
                 register_trace_##probe_name(probe_##probe_name, NULL)
 #       define GATOR_UNREGISTER_TRACE(probe_name) \
                 unregister_trace_##probe_name(probe_##probe_name, NULL)
+#else
+#       define GATOR_DEFINE_PROBE(probe_name, proto) \
+                extern struct tracepoint *gator_tracepoint_##probe_name; \
+                static void probe_##probe_name(void *data, PARAMS(proto))
+#       define GATOR_REGISTER_TRACE(probe_name) \
+                tracepoint_probe_register(gator_tracepoint_##probe_name, probe_##probe_name, NULL)
+#       define GATOR_UNREGISTER_TRACE(probe_name) \
+                tracepoint_probe_unregister(gator_tracepoint_##probe_name, probe_##probe_name, NULL)
 #endif
 
 /******************************************************************************
diff --git a/driver/gator_main.c b/driver/gator_main.c
index 4a1f056..55772ef 100644
--- a/driver/gator_main.c
+++ b/driver/gator_main.c
@@ -1349,8 +1349,61 @@ static void gator_op_create_files(struct super_block *sb, struct dentry *root)
 /******************************************************************************
  * Module
  ******************************************************************************/
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 15, 0)
+
+#define GATOR_TRACEPOINTS \
+        GATOR_HANDLE_TRACEPOINT(block_rq_complete); \
+        GATOR_HANDLE_TRACEPOINT(cpu_frequency); \
+        GATOR_HANDLE_TRACEPOINT(cpu_idle); \
+        GATOR_HANDLE_TRACEPOINT(cpu_migrate_begin); \
+        GATOR_HANDLE_TRACEPOINT(cpu_migrate_current); \
+        GATOR_HANDLE_TRACEPOINT(cpu_migrate_finish); \
+        GATOR_HANDLE_TRACEPOINT(irq_handler_exit); \
+        GATOR_HANDLE_TRACEPOINT(mali_hw_counter); \
+        GATOR_HANDLE_TRACEPOINT(mali_job_slots_event); \
+        GATOR_HANDLE_TRACEPOINT(mali_mmu_as_in_use); \
+        GATOR_HANDLE_TRACEPOINT(mali_mmu_as_released); \
+        GATOR_HANDLE_TRACEPOINT(mali_page_fault_insert_pages); \
+        GATOR_HANDLE_TRACEPOINT(mali_pm_status); \
+        GATOR_HANDLE_TRACEPOINT(mali_sw_counter); \
+        GATOR_HANDLE_TRACEPOINT(mali_sw_counters); \
+        GATOR_HANDLE_TRACEPOINT(mali_timeline_event); \
+        GATOR_HANDLE_TRACEPOINT(mali_total_alloc_pages_change); \
+        GATOR_HANDLE_TRACEPOINT(mm_page_alloc); \
+        GATOR_HANDLE_TRACEPOINT(mm_page_free); \
+        GATOR_HANDLE_TRACEPOINT(mm_page_free_batched); \
+        GATOR_HANDLE_TRACEPOINT(sched_process_fork); \
+        GATOR_HANDLE_TRACEPOINT(sched_process_free); \
+        GATOR_HANDLE_TRACEPOINT(sched_switch); \
+        GATOR_HANDLE_TRACEPOINT(softirq_exit); \
+
+#define GATOR_HANDLE_TRACEPOINT(probe_name) \
+        struct tracepoint *gator_tracepoint_##probe_name
+GATOR_TRACEPOINTS;
+#undef GATOR_HANDLE_TRACEPOINT
+
+static void gator_fct(struct tracepoint *tp, void *priv)
+{
+#define GATOR_HANDLE_TRACEPOINT(probe_name) \
+        if (strcmp(tp->name, #probe_name) == 0) { \
+                gator_tracepoint_##probe_name = tp; \
+                return; \
+        }
+GATOR_TRACEPOINTS;
+#undef GATOR_HANDLE_TRACEPOINT
+}
+
+#else
+
+#define for_each_kernel_tracepoint(fct, priv)
+
+#endif
+
 static int __init gator_module_init(void)
 {
+        for_each_kernel_tracepoint(gator_fct, NULL);
+
         if (gatorfs_register()) {
                 return -1;
         }