oprofile: modify op_cpu_buffer_read_entry()

This implements the support of samples with attached data.

Signed-off-by: Robert Richter <robert.richter@amd.com>

3 files changed, 25 insertions, 14 deletions

diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index 21fd249b6e0b..908202afbae9 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -329,9 +329,10 @@ static void add_ibs_begin(int cpu, int code, struct mm_struct *mm)
         int i, count;
         unsigned long cookie = 0;
         off_t offset;
+        struct op_entry entry;
         struct op_sample *sample;
 
-        sample = op_cpu_buffer_read_entry(cpu);
+        sample = op_cpu_buffer_read_entry(&entry, cpu);
         if (!sample)
                 return;
         pc = sample->eip;
@@ -370,7 +371,7 @@ static void add_ibs_begin(int cpu, int code, struct mm_struct *mm)
                 count = IBS_OP_CODE_SIZE;       /*IBS OP is 5 int64s*/
 
         for (i = 0; i < count; i++) {
-                sample = op_cpu_buffer_read_entry(cpu);
+                sample = op_cpu_buffer_read_entry(&entry, cpu);
                 if (!sample)
                         return;
                 add_event_entry(sample->eip);
@@ -528,6 +529,8 @@ void sync_buffer(int cpu)
         sync_buffer_state state = sb_buffer_start;
         unsigned int i;
         unsigned long available;
+        struct op_entry entry;
+        struct op_sample *sample;
 
         mutex_lock(&buffer_mutex);
 
@@ -537,19 +540,19 @@ void sync_buffer(int cpu)
         available = op_cpu_buffer_entries(cpu);
 
         for (i = 0; i < available; ++i) {
-                struct op_sample *s = op_cpu_buffer_read_entry(cpu);
-                if (!s)
+                sample = op_cpu_buffer_read_entry(&entry, cpu);
+                if (!sample)
                         break;
 
-                if (is_code(s->eip)) {
-                        switch (s->event) {
+                if (is_code(sample->eip)) {
+                        switch (sample->event) {
                         case 0:
                         case CPU_IS_KERNEL:
                                 /* kernel/userspace switch */
-                                in_kernel = s->event;
+                                in_kernel = sample->event;
                                 if (state == sb_buffer_start)
                                         state = sb_sample_start;
-                                add_kernel_ctx_switch(s->event);
+                                add_kernel_ctx_switch(sample->event);
                                 break;
                         case CPU_TRACE_BEGIN:
                                 state = sb_bt_start;
@@ -566,7 +569,7 @@ void sync_buffer(int cpu)
                         default:
                                 /* userspace context switch */
                                 oldmm = mm;
-                                new = (struct task_struct *)s->event;
+                                new = (struct task_struct *)sample->event;
                                 release_mm(oldmm);
                                 mm = take_tasks_mm(new);
                                 if (mm != oldmm)
@@ -581,7 +584,7 @@ void sync_buffer(int cpu)
                         /* ignore sample */
                         continue;
 
-                if (add_sample(mm, s, in_kernel))
+                if (add_sample(mm, sample, in_kernel))
                         continue;
 
                 /* ignore backtraces if failed to add a sample */
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 934ff159e70e..400f7fcffdbe 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -182,20 +182,28 @@ int op_cpu_buffer_write_commit(struct op_entry *entry)
                                          entry->irq_flags);
 }
 
-struct op_sample *op_cpu_buffer_read_entry(int cpu)
+struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu)
 {
         struct ring_buffer_event *e;
         e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
         if (e)
-                return ring_buffer_event_data(e);
+                goto event;
         if (ring_buffer_swap_cpu(op_ring_buffer_read,
                                  op_ring_buffer_write,
                                  cpu))
                 return NULL;
         e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
         if (e)
-                return ring_buffer_event_data(e);
+                goto event;
         return NULL;
+
+event:
+        entry->event = e;
+        entry->sample = ring_buffer_event_data(e);
+        entry->size = (ring_buffer_event_length(e) - sizeof(struct op_sample))
+                / sizeof(entry->sample->data[0]);
+        entry->data = entry->sample->data;
+        return entry->sample;
 }
 
 unsigned long op_cpu_buffer_entries(int cpu)
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index 2d4bfdeb7fba..d7c0545ef8b2 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -75,7 +75,7 @@ static inline void op_cpu_buffer_reset(int cpu)
 struct op_sample
 *op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
 int op_cpu_buffer_write_commit(struct op_entry *entry);
-struct op_sample *op_cpu_buffer_read_entry(int cpu);
+struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu);
 unsigned long op_cpu_buffer_entries(int cpu);
 
 /* transient events for the CPU buffer -> event buffer */