lscpu: support discontinuous NUMA nodes

lscpu fails to print proper NUMA node values in a system with
discontinuous nodes. This patch adds support by creating a nodeidx
array to map node numbers.

Based on patch from Madhavan Srinivasan <maddy@linux.vnet.ibm.com>.

Reported-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c
index 8f14b3af2818c1ed2928aea989071b02fb9eef81..0e937e1cd14c107b8b887b6ada50dcbb4b2b7b31 100644 (file)
--- a/sys-utils/lscpu.c
+++ b/sys-utils/lscpu.c
@@ -50,6 +50,7 @@
 /* /sys paths */
 #define _PATH_SYS_SYSTEM       "/sys/devices/system"
 #define _PATH_SYS_CPU          _PATH_SYS_SYSTEM "/cpu"
+#define _PATH_SYS_NODE         _PATH_SYS_SYSTEM "/node"
 #define _PATH_PROC_XEN         "/proc/xen"
 #define _PATH_PROC_XENCAP      _PATH_PROC_XEN "/capabilities"
 #define _PATH_PROC_CPUINFO     "/proc/cpuinfo"
@@ -177,6 +178,7 @@ struct lscpu_desc {
        int             *idx2cpunum;    /* mapping index to CPU num */
 
        int             nnodes;         /* number of NUMA modes */
+       int             *idx2nodenum;   /* Support for discontinuous nodes */
        cpu_set_t       **nodemaps;     /* array with NUMA nodes */
 
        /* books -- based on book_siblings (internal kernel map of cpuX's
@@ -912,25 +914,59 @@ read_cache(struct lscpu_desc *desc, int idx)
        }
 }
 
+static inline int is_node_dirent(struct dirent *d)
+{
+       return
+               d &&
+#ifdef _DIRENT_HAVE_D_TYPE
+               d->d_type == DT_DIR &&
+#endif
+               strncmp(d->d_name, "node", 4) == 0 &&
+               isdigit_string(d->d_name + 4);
+}
+
 static void
 read_nodes(struct lscpu_desc *desc)
 {
-       int i;
+       int i = 0;
+       DIR *dir;
+       struct dirent *d;
+       char *path;
 
        /* number of NUMA node */
-       while (path_exist(_PATH_SYS_SYSTEM "/node/node%d", desc->nnodes))
-               desc->nnodes++;
+       path = path_strdup(_PATH_SYS_NODE);
+       dir = opendir(path);
+       free(path);
 
-       if (!desc->nnodes)
+       while (dir && (d = readdir(dir))) {
+               if (is_node_dirent(d))
+                       desc->nnodes++;
+       }
+
+       if (!desc->nnodes) {
+               if (dir)
+                       closedir(dir);
                return;
+       }
 
        desc->nodemaps = xcalloc(desc->nnodes, sizeof(cpu_set_t *));
+       desc->idx2nodenum = xmalloc(desc->nnodes * sizeof(int));
+
+       if (dir) {
+               rewinddir(dir);
+               while ((d = readdir(dir)) && i < desc->nnodes) {
+                       if (is_node_dirent(d))
+                               desc->idx2nodenum[i++] = strtol_or_err(((d->d_name) + 4),
+                                                       _("Failed to extract the node number"));
+               }
+               closedir(dir);
+       }
 
        /* information about how nodes share different CPUs */
        for (i = 0; i < desc->nnodes; i++)
                desc->nodemaps[i] = path_read_cpuset(maxcpus,
                                        _PATH_SYS_SYSTEM "/node/node%d/cpumap",
-                                       i);
+                                       desc->idx2nodenum[i]);
 }
 
 static char *
@@ -961,7 +997,7 @@ get_cell_data(struct lscpu_desc *desc, int idx, int col,
        case COL_NODE:
                if (cpuset_ary_isset(cpu, desc->nodemaps,
                                     desc->nnodes, setsize, &i) == 0)
-                       snprintf(buf, bufsz, "%zd", i);
+                       snprintf(buf, bufsz, "%d", desc->idx2nodenum[i]);
                break;
        case COL_BOOK:
                if (cpuset_ary_isset(cpu, desc->bookmaps,
@@ -1378,7 +1414,7 @@ print_summary(struct lscpu_desc *desc, struct lscpu_modifier *mod)
        }
 
        for (i = 0; i < desc->nnodes; i++) {
-               snprintf(buf, sizeof(buf), _("NUMA node%d CPU(s):"), i);
+               snprintf(buf, sizeof(buf), _("NUMA node%d CPU(s):"), desc->idx2nodenum[i]);
                print_cpuset(buf, desc->nodemaps[i], mod->hex);
        }
 }