From a663f2c11bb0e8ddc608944ed267dacac35ef2d2 Mon Sep 17 00:00:00 2001
From: Rodrigo Arias <rodrigo.arias@bsc.es>
Date: Thu, 18 Nov 2021 18:27:28 +0100
Subject: [PATCH] Allocate only the required CPUs

---
 emu.c      | 41 +++++++++++++++++++++++++++++++++++------
 emu.h      |  2 +-
 emu_ovni.c |  2 +-
 ovni.h     |  1 -
 4 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/emu.c b/emu.c
index 4c7bdcb..6c26796 100644
--- a/emu.c
+++ b/emu.c
@@ -540,11 +540,15 @@ add_new_cpu(struct ovni_emu *emu, struct ovni_loom *loom, int i, int phyid)
 {
 	struct ovni_cpu *cpu;
 
-	/* The logical id must match our index */
-	assert((size_t) i == loom->ncpus);
-
 	cpu = &loom->cpu[i];
 
+	if(i < 0 || i >= (int) loom->ncpus)
+	{
+		err("CPU with index %d in loom %s is out of bounds\n", i,
+				loom->hostname);
+		abort();
+	}
+
 	assert(cpu->state == CPU_ST_UNKNOWN);
 
 	cpu->state = CPU_ST_READY;
@@ -554,8 +558,6 @@ add_new_cpu(struct ovni_emu *emu, struct ovni_loom *loom, int i, int phyid)
 	cpu->loom = loom;
 
 	dbg("new cpu %d at phyid=%d\n", cpu->gindex, phyid);
-
-	loom->ncpus++;
 }
 
 static void
@@ -579,16 +581,41 @@ proc_load_cpus(struct ovni_emu *emu, struct ovni_loom *loom, struct ovni_eproc *
 
 	assert(loom->ncpus == 0);
 
-	for(i = 0; i < json_array_get_count(cpuarray); i++)
+	loom->ncpus = json_array_get_count(cpuarray);
+
+	if(loom->ncpus <= 0)
+	{
+		err("loom %s proc %d has read %ld cpus, but required > 0\n",
+				loom->hostname, proc->pid, loom->ncpus);
+		abort();
+	}
+
+	loom->cpu = calloc(loom->ncpus, sizeof(struct ovni_cpu));
+
+	if(loom->cpu == NULL)
+	{
+		perror("calloc failed");
+		abort();
+	}
+
+	for(i = 0; i < loom->ncpus; i++)
 	{
 		cpu = json_array_get_object(cpuarray, i);
 
+		if(cpu == NULL)
+		{
+			err("json_array_get_object returned NULL\n");
+			abort();
+		}
+
 		index = (int) json_object_get_number(cpu, "index");
 		phyid = (int) json_object_get_number(cpu, "phyid");
 
 		add_new_cpu(emu, loom, index, phyid);
 	}
 
+	/* If we reach this point, all CPUs are in the ready state */
+
 	/* Init the vcpu as well */
 	vcpu = &loom->vcpu;
 	assert(vcpu->state == CPU_ST_UNKNOWN);
@@ -651,6 +678,8 @@ destroy_metadata(struct ovni_emu *emu)
 			assert(proc->meta);
 			json_value_free(proc->meta);
 		}
+
+		free(loom->cpu);
 	}
 
 	return 0;
diff --git a/emu.h b/emu.h
index 8b253b0..16aaaa3 100644
--- a/emu.h
+++ b/emu.h
@@ -381,7 +381,7 @@ struct ovni_loom {
 	size_t max_phyid;
 	size_t ncpus;
 	size_t offset_ncpus;
-	struct ovni_cpu cpu[OVNI_MAX_CPU];
+	struct ovni_cpu *cpu;
 
 	int64_t clock_offset;
 
diff --git a/emu_ovni.c b/emu_ovni.c
index 642a727..f06aa29 100644
--- a/emu_ovni.c
+++ b/emu_ovni.c
@@ -187,7 +187,7 @@ update_cpu(struct ovni_cpu *cpu)
 struct ovni_cpu *
 emu_get_cpu(struct ovni_loom *loom, int cpuid)
 {
-	assert(cpuid < OVNI_MAX_CPU);
+	assert(cpuid < (int) loom->ncpus);
 
 	if(cpuid < 0)
 	{
diff --git a/ovni.h b/ovni.h
index 91e0cda..ee542b6 100644
--- a/ovni.h
+++ b/ovni.h
@@ -40,7 +40,6 @@ extern "C" {
 /* Hardcode the JSON_Value to avoid a dependency with janson */
 typedef struct json_value_t  JSON_Value;
 
-#define OVNI_MAX_CPU 256
 #define OVNI_TRACEDIR "ovni"
 #define OVNI_MAX_HOSTNAME 512