[NPS-F] Rework add_server() API

- add_server() syscall takes a npsf_id and an array of struct 'npsf_budgets'.
  Each entry of the array is a tuple (cpu, budget) that defines the budget
  reserved for the server 'npsf_id' on the cpu 'cpu'.
- Input data is read from a file with struture: "npsf_id cpu budget-us"

3 files changed, 87 insertions, 33 deletions

diff --git a/bin/npsf_add_server.c b/bin/npsf_add_server.c
index 3983e77..9fa59c0 100644
--- a/bin/npsf_add_server.c
+++ b/bin/npsf_add_server.c
@@ -1,4 +1,8 @@
-/* wrapper for sys_add_server */
+/* wrapper for sys_add_server
+ *
+ * Input: a file with on each line:
+ * npsf_id cpu budget(us)
+ */
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -9,37 +13,96 @@
 void usage(char *error) {
         fprintf(stderr, "Error: %s\n", error);
         fprintf(stderr,
-                "Usage: npsf_add_server NPSF-ID UTIL SLOT-SIZE(ms) CPU \n");
+                "Usage: npsf_add_server SERVERS-FILE MAX-SPLITS-PER-NPSFID\n");
         exit(1);
 }
 
 int main(int argc, char** argv)
 {
         int ret;
-        int cpu = 0;
-        int npsf_id = 0;
-        double util = 0;
-        int slot_ms = 0;
-        lt_t budget_ns = 0;
+        FILE *file;
+        int i,j;
+        int npsf_id, curr_id = -1;
+        int cpu, max_splits_server;
+        int budget_us;
+        struct npsf_budgets *budgets;
 
-        if (argc < 5)
+        if (argc < 3)
                 usage("Arguments missing.");
-        npsf_id = atoi(argv[1]);
-        util    = atof(argv[2]);
-        slot_ms = atoi(argv[3]);
-        cpu     = atoi(argv[4]);
 
-        if (util > 1)
-                usage("Utilization > 1");
+        max_splits_server = atoi(argv[2]);
 
-        budget_ns = (lt_t)((__NS_PER_MS * util) * slot_ms);
+        if ((file = fopen(argv[1], "r")) == NULL) {
+                fprintf(stderr, "Cannot open %s\n", argv[1]);
+                return -1;
+        }
 
-        printf("Trying to add NP(%d): budget = %f\n", npsf_id, (double)(budget_ns) / __NS_PER_MS);
+        /* format: npsf_id cpu budget-us */
+        i = 0;
+        while (fscanf(file, "%d %d %d\n", &npsf_id, &cpu, &budget_us) != EOF) {
 
-        ret = add_server(&npsf_id, &budget_ns, &cpu);
+                printf("Read: %d %d %d\n", npsf_id, cpu, budget_us);
 
-        if (ret < 0)
+                if (curr_id == -1) {
+                        curr_id = npsf_id;
+                        budgets = malloc(max_splits_server *
+                                        sizeof(struct npsf_budgets));
+                        for(j = 0; j < max_splits_server; j++) {
+                                budgets[j].cpu = -1;
+                                budgets[j].budget = 0;
+                        }
+                }
+
+                if (npsf_id == curr_id) {
+                        /* same notional processor, different cpu and budget */
+                        budgets[i].cpu = cpu;
+                        budgets[i].budget = (lt_t) (budget_us * 1000);
+                        i++;
+                } else {
+                        /* different notional processor */
+                        /* add server */
+                        printf("Adding npsf_id = %d\n", curr_id);
+                        ret = add_server(&curr_id, budgets);
+
+                        if (ret < 0) {
+                                fclose(file);
+                                free(budgets);
+                                printf("Cannot add Notional Processor %d\n",
+                                                curr_id);
+                                return ret;
+                        }
+
+                        /* reinit new */
+                        i = 0;
+                        budgets = malloc(max_splits_server *
+                                        sizeof(struct npsf_budgets));
+                        for(j = 0; j < max_splits_server; j++) {
+                                budgets[j].cpu = -1;
+                                budgets[j].budget = 0;
+                        }
+                        curr_id = npsf_id;
+                        budgets[i].cpu = cpu;
+                        budgets[i].budget = (lt_t) (budget_us * 1000);
+                        i++;
+                }
+        }
+
+        if (ferror(file)) {
+                fprintf(stderr, "Error while reading\n");
+                fclose(file);
+                return -1;
+        }
+
+        /* save the last entry */
+        ret = add_server(&curr_id, budgets);
+        printf("Adding npsf_id = %d\n", curr_id);
+        if (ret < 0) {
+                fclose(file);
+                free(budgets);
                 bail_out("Cannot add Notional Processor: ");
+        }
+
+        fclose(file);
 
         return 0;
 }
diff --git a/include/litmus.h b/include/litmus.h
index 9d2339f..0ccad9f 100644
--- a/include/litmus.h
+++ b/include/litmus.h
@@ -150,24 +150,15 @@ int null_call(cycles_t *timestamp);
 struct control_page* get_ctrl_page(void);
 
 /* NPS-F syscall to add a notional processor (a server) to a cpu.
- * A notional processor may span across multiple cpu. If the NP.
- * spans multiple cpus, each "segment" must be initialized indipendently
- * with the proper fraction of budget of the original NP. For example:
- *
- * NP1 = 0.75 = inflated utilization; it spans on CPU0 and CPU1:
- * NP1_0 = 0.2; NP1_1 = 0.55
- *
- * So, we have to initialize a segment (0.2 * slot_length) on CPU0
- * and a segment (0.55 * slot_length) on CPU1 (both should have
- * the same npsf_id).
+ * A notional processor may span across multiple cpu.
  *
  * @npsf_id:    a "unique" identifier for the notional processor.
- * @budget:     the length of the segment for this NP. on this CPU (in ns).
- * @cpu:        the cpu that holds this NP segment.
+ * @budgets:    array of (cpu, budget-ns) that describes this np.
+ *              on possibly more than one cpu.
  *
  * Currently implemented on x86_64 only.
  */
-int add_server(int *npsf_id, lt_t *budget, int *cpu);
+int add_server(int *npsf_id, struct npsf_budgets *budgets);
 
 #ifdef __cplusplus
 }
diff --git a/src/syscalls.c b/src/syscalls.c
index 58d7151..6df716b 100644
--- a/src/syscalls.c
+++ b/src/syscalls.c
@@ -96,7 +96,7 @@ int null_call(cycles_t *timestamp)
         return syscall(__NR_null_call, timestamp);
 }
 
-int add_server(int *npsf_id, lt_t *budget, int *cpu)
+int add_server(int *npsf_id, struct npsf_budgets *budgets)
 {
-        return syscall(__NR_add_server, npsf_id, budget, cpu);
+        return syscall(__NR_add_server, npsf_id, budgets);
 }