libxl: allow to allocate cpumap with specific size

Currently, libxl_cpumap_alloc()allocate the cpumap with size of number
of physical cpus. In some place, we may want to allocate specific size
of cpumap.  This patch allow to pass a argument to specific the size
that you want to allocate. If pass 0, it means the size is equal to
number of physical cpus.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

5 files changed, 23 insertions, 21 deletions

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 6fc5472bb7..205c1e61de 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -570,7 +570,7 @@ static int cpupool_info(libxl__gc *gc,
     info->poolid = xcinfo->cpupool_id;
     info->sched = xcinfo->sched_id;
     info->n_dom = xcinfo->n_dom;
-    if (libxl_cpumap_alloc(CTX, &info->cpumap))
+    if (libxl_cpumap_alloc(CTX, &info->cpumap, 0))
         goto out;
     memcpy(info->cpumap.map, xcinfo->cpumap, info->cpumap.size);
 
@@ -3288,7 +3288,7 @@ libxl_vcpuinfo *libxl_list_vcpu(libxl_ctx *ctx, uint32_t domid,
     }
 
     for (*nb_vcpu = 0; *nb_vcpu <= domaininfo.max_vcpu_id; ++*nb_vcpu, ++ptr) {
-        if (libxl_cpumap_alloc(ctx, &ptr->cpumap)) {
+        if (libxl_cpumap_alloc(ctx, &ptr->cpumap, 0)) {
             LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "allocating cpumap");
             return NULL;
         }
@@ -4041,8 +4041,8 @@ int libxl_cpupool_destroy(libxl_ctx *ctx, uint32_t poolid)
     if ((info->cpupool_id != poolid) || (info->n_dom))
         goto out;
 
-    rc = ERROR_NOMEM;
-    if (libxl_cpumap_alloc(ctx, &cpumap))
+    rc = libxl_cpumap_alloc(ctx, &cpumap, 0);
+    if (rc)
         goto out;
 
     memcpy(cpumap.map, info->cpumap, cpumap.size);
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index 67cd207379..08e5536c0c 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -205,8 +205,8 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
         b_info->cur_vcpus = 1;
 
     if (!b_info->cpumap.size) {
-        if (libxl_cpumap_alloc(CTX, &b_info->cpumap))
-            return ERROR_NOMEM;
+        if (libxl_cpumap_alloc(CTX, &b_info->cpumap, 0))
+            return ERROR_FAIL;
         libxl_cpumap_set_any(&b_info->cpumap);
     }
 
diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
index 67ef82c8e4..2acf7d4a43 100644
--- a/tools/libxl/libxl_utils.c
+++ b/tools/libxl/libxl_utils.c
@@ -489,19 +489,19 @@ int libxl_mac_to_device_nic(libxl_ctx *ctx, uint32_t domid,
     return rc;
 }
 
-int libxl_cpumap_alloc(libxl_ctx *ctx, libxl_cpumap *cpumap)
+int libxl_cpumap_alloc(libxl_ctx *ctx, libxl_cpumap *cpumap, int max_cpus)
 {
-    int max_cpus;
     int sz;
 
-    max_cpus = libxl_get_max_cpus(ctx);
+    if (max_cpus < 0)
+        return ERROR_INVAL;
+    if (max_cpus == 0)
+        max_cpus = libxl_get_max_cpus(ctx);
     if (max_cpus == 0)
         return ERROR_FAIL;
 
     sz = (max_cpus + 7) / 8;
-    cpumap->map = calloc(sz, sizeof(*cpumap->map));
-    if (!cpumap->map)
-        return ERROR_NOMEM;
+    cpumap->map = libxl__calloc(NULL, sizeof(*cpumap->map), sz);
     cpumap->size = sz;
     return 0;
 }
diff --git a/tools/libxl/libxl_utils.h b/tools/libxl/libxl_utils.h
index 74beb52a67..7ab0c0915c 100644
--- a/tools/libxl/libxl_utils.h
+++ b/tools/libxl/libxl_utils.h
@@ -63,7 +63,7 @@ int libxl_devid_to_device_nic(libxl_ctx *ctx, uint32_t domid, int devid,
 int libxl_vdev_to_device_disk(libxl_ctx *ctx, uint32_t domid, const char *vdev,
                                libxl_device_disk *disk);
 
-int libxl_cpumap_alloc(libxl_ctx *ctx, libxl_cpumap *cpumap);
+int libxl_cpumap_alloc(libxl_ctx *ctx, libxl_cpumap *cpumap, int max_cpus);
 int libxl_cpumap_test(libxl_cpumap *cpumap, int cpu);
 void libxl_cpumap_set(libxl_cpumap *cpumap, int cpu);
 void libxl_cpumap_reset(libxl_cpumap *cpumap, int cpu);
diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index c80b9fb55d..02b55f1305 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -503,7 +503,7 @@ static int vcpupin_parse(char *cpu, libxl_cpumap *cpumap)
         return 0;
     }
 
-    if (libxl_cpumap_alloc(ctx, &exclude_cpumap)) {
+    if (libxl_cpumap_alloc(ctx, &exclude_cpumap, 0)) {
         fprintf(stderr, "Error: Failed to allocate cpumap.\n");
         return ENOMEM;
     }
@@ -656,7 +656,7 @@ static void parse_config_data(const char *config_source,
     if (!xlu_cfg_get_list (config, "cpus", &cpus, 0, 1)) {
         int i, n_cpus = 0;
 
-        if (libxl_cpumap_alloc(ctx, &b_info->cpumap)) {
+        if (libxl_cpumap_alloc(ctx, &b_info->cpumap, 0)) {
             fprintf(stderr, "Unable to allocate cpumap\n");
             exit(1);
         }
@@ -692,7 +692,7 @@ static void parse_config_data(const char *config_source,
     else if (!xlu_cfg_get_string (config, "cpus", &buf, 0)) {
         char *buf2 = strdup(buf);
 
-        if (libxl_cpumap_alloc(ctx, &b_info->cpumap)) {
+        if (libxl_cpumap_alloc(ctx, &b_info->cpumap, 0)) {
             fprintf(stderr, "Unable to allocate cpumap\n");
             exit(1);
         }
@@ -1779,7 +1779,9 @@ start:
     if (vcpu_to_pcpu) {
         libxl_cpumap vcpu_cpumap;
 
-        libxl_cpumap_alloc(ctx, &vcpu_cpumap);
+        ret = libxl_cpumap_alloc(ctx, &vcpu_cpumap, 0);
+        if (ret)
+            goto error_out;
         for (i = 0; i < d_config.b_info.max_vcpus; i++) {
 
             if (vcpu_to_pcpu[i] != -1) {
@@ -4051,7 +4053,7 @@ static void vcpupin(const char *d, const char *vcpu, char *cpu)
 
     find_domain(d);
 
-    if (libxl_cpumap_alloc(ctx, &cpumap)) {
+    if (libxl_cpumap_alloc(ctx, &cpumap, 0)) {
         goto vcpupin_out;
     }
 
@@ -4108,7 +4110,7 @@ static void vcpuset(const char *d, const char* nr_vcpus)
 
     find_domain(d);
 
-    if (libxl_cpumap_alloc(ctx, &cpumap)) {
+    if (libxl_cpumap_alloc(ctx, &cpumap, 0)) {
         fprintf(stderr, "libxl_cpumap_alloc failed\n");
         return;
     }
@@ -5921,7 +5923,7 @@ int main_cpupoolcreate(int argc, char **argv)
         fprintf(stderr, "libxl_get_freecpus failed\n");
         goto out_cfg;
     }
-    if (libxl_cpumap_alloc(ctx, &cpumap)) {
+    if (libxl_cpumap_alloc(ctx, &cpumap, 0)) {
         fprintf(stderr, "Failed to allocate cpumap\n");
         goto out_cfg;
     }
@@ -6289,7 +6291,7 @@ int main_cpupoolnumasplit(int argc, char **argv)
         return -ERROR_FAIL;
     }
 
-    if (libxl_cpumap_alloc(ctx, &cpumap)) {
+    if (libxl_cpumap_alloc(ctx, &cpumap, 0)) {
         fprintf(stderr, "Failed to allocate cpumap\n");
         libxl_cputopology_list_free(topology, n_cpus);
         return -ERROR_FAIL;