Generalized GPU cost predictors + EWMA. (untested)wip-gpu-rtas12

4 files changed, 88 insertions, 27 deletions

diff --git a/include/litmus/gpu_affinity.h b/include/litmus/gpu_affinity.h
index d64a15cbf2a5..a2abc4c1fd7c 100644
--- a/include/litmus/gpu_affinity.h
+++ b/include/litmus/gpu_affinity.h
@@ -31,18 +31,20 @@ static inline lt_t get_gpu_time(struct task_struct* t)
 
 static inline lt_t get_gpu_estimate(struct task_struct* t, gpu_migration_dist_t dist)
 {
-//      int i;
-//      fpbuf_t temp = _fp_to_integer(t->rt_param.gpu_migration_est[dist].est);
-//      lt_t val = (temp >= 0) ? temp : 0;  // never allow negative estimates...
-        lt_t val = t->rt_param.gpu_migration_est[dist].avg;
-
-//      WARN_ON(temp < 0);
-
-        // lower-bound a distant migration to be at least equal to the level
-        // below it.
-//      for(i = dist-1; (val == 0) && (i >= MIG_LOCAL); --i) {
-//              val = _fp_to_integer(t->rt_param.gpu_migration_est[i].est);
-//      }
+        lt_t val = 0;
+
+        switch(t->rt_param.prediction_mode) {
+                case SIMPLE_AVG:
+                case CC_BRUTE_AVG:
+                case CC_MR_AVG:
+                        val = t->rt_param.gpu_avg_est[dist].center_line;
+                        break;
+                case SIMPLE_EWMA:
+                case CC_BRUTE_EWMA:
+                case CC_MR_EWMA:
+                        val = t->rt_param.gpu_ewma_est[dist].center_line;
+                        break;
+        }
 
         return ((val > 0) ? val : dist+1);
 }
diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h
index 44f85a366574..6da36f50240d 100644
--- a/include/litmus/rt_param.h
+++ b/include/litmus/rt_param.h
@@ -41,6 +41,32 @@ typedef enum {
         PRECISE_SIGNALS,        /* budget signals are triggered with hrtimers */
 } budget_signal_policy_t;
 
+typedef enum
+{
+        /* simple - all observations counted */
+        SIMPLE_AVG = 1,
+        SIMPLE_EWMA,
+
+        /* control chart, brute - std deviation fully calculated */
+        CC_BRUTE_AVG,
+        CC_BRUTE_EWMA,
+
+        /* control chart, moving range - std deviation est. from moving range */
+        CC_MR_AVG,
+        CC_MR_EWMA,
+} predictor_type;
+
+typedef struct predictor
+{
+        predictor_type type;
+        uint16_t window_size;
+
+        uint8_t sigmas;
+        uint16_t alpha_num;
+        uint16_t alpha_denom;
+} predictor_t;
+
+
 /* We use the common priority interpretation "lower index == higher priority",
  * which is commonly used in fixed-priority schedulability analysis papers.
  * So, a numerically lower priority value implies higher scheduling priority,
@@ -180,23 +206,48 @@ typedef enum gpu_migration_dist
         MIG_LAST = MIG_NONE
 } gpu_migration_dist_t;
 
-typedef struct feedback_est{
-        fp_t est;
-        fp_t accum_err;
-} feedback_est_t;
-
-
 #define AVG_EST_WINDOW_SIZE 20
 
-typedef struct avg_est{
-        lt_t history[AVG_EST_WINDOW_SIZE];
+typedef struct obs_history
+{
+        uint16_t window_size;
         uint16_t count;
         uint16_t idx;
+        uint16_t ridx;
+        
+        lt_t last_observed;
+        lt_t *observations;
+        lt_t *range;
+} obs_history_t;
+
+typedef struct avg_est {
+        uint8_t sigmas;
+
+        obs_history_t history;
+
         lt_t sum;
+        lt_t rsum;
+
         lt_t std;
-        lt_t avg;
+        lt_t center_line;
 } avg_est_t;
 
+
+typedef struct ewma_est {
+        uint8_t sigmas;
+        uint16_t alpha_num;
+        uint16_t alpha_denom;
+
+        obs_history_t history;
+        
+        lt_t rsum;
+
+        lt_t std;
+        lt_t center_line;
+} ewma_est_t;
+
+
+
 /*      RT task parameters for scheduling extensions
  *      These parameters are inherited during clone and therefore must
  *      be explicitly set up before the task set is launched.
@@ -243,7 +294,13 @@ struct rt_param {
         long unsigned int                       held_gpus;  // bitmap of held GPUs.
 
 #ifdef CONFIG_LITMUS_AFFINITY_LOCKING
-        avg_est_t gpu_migration_est[MIG_LAST+1];
+//      avg_est_t gpu_migration_est[MIG_LAST+1];
+        predictor_type  prediction_mode;
+        union
+        {
+                avg_est_t gpu_avg_est[MIG_LAST+1];
+                ewma_est_t gpu_ewma_est[MIG_LAST+1];
+        };
 
         gpu_migration_dist_t    gpu_migration;
         int                             last_gpu;
diff --git a/include/litmus/unistd_32.h b/include/litmus/unistd_32.h
index c86b743408ed..964f02082275 100644
--- a/include/litmus/unistd_32.h
+++ b/include/litmus/unistd_32.h
@@ -21,6 +21,7 @@
 #define __NR_litmus_dgl_unlock  __LSC(13)
 #define __NR_register_nv_device                 __LSC(14)
 
-#define __NR_set_aux_tasks              _LSC(15)
+#define __NR_config_gpu_affinity_predictor __LSC(15)
+#define __NR_set_aux_tasks              _LSC(16)
 
-#define NR_litmus_syscalls 16
+#define NR_litmus_syscalls 17
diff --git a/include/litmus/unistd_64.h b/include/litmus/unistd_64.h
index 3825bc129dbd..70be98d4f1e7 100644
--- a/include/litmus/unistd_64.h
+++ b/include/litmus/unistd_64.h
@@ -35,8 +35,9 @@ __SYSCALL(__NR_litmus_dgl_lock, sys_litmus_dgl_lock)
 __SYSCALL(__NR_litmus_dgl_unlock, sys_litmus_dgl_unlock)
 #define __NR_register_nv_device         __LSC(14)
 __SYSCALL(__NR_register_nv_device, sys_register_nv_device)
-
-#define __NR_set_aux_tasks                      __LSC(15)
+#define __NR_config_gpu_affinity_predictor      __LSC(15)
+__SYSCALL(__NR_config_gpu_affinity_predictor, sys_config_gpu_affinity_predictor)
+#define __NR_set_aux_tasks                      __LSC(16)
 __SYSCALL(__NR_set_aux_tasks, sys_set_aux_tasks)
 
-#define NR_litmus_syscalls 16
+#define NR_litmus_syscalls 17