libxl,libxc: introduce libxl_get_numainfo()

Make some NUMA node information available to the toolstack. Achieve
this by means of xc_numainfo(), which exposes memory size and amount
of free memory of each node, as well as the relative distances of
each node to all the others.

For properly exposing distances we need the IDL to support arrays.

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index 812b127ff35911badef9a196b3c9a468515ab074..3c5d64a4d1a67d74803a27943141be7467ae3924 100644 (file)
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -35,6 +35,20 @@ int xc_get_max_cpus(xc_interface *xch)
     return max_cpus;
 }
 
+int xc_get_max_nodes(xc_interface *xch)
+{
+    static int max_nodes = 0;
+    xc_physinfo_t physinfo;
+
+    if ( max_nodes )
+        return max_nodes;
+
+    if ( !xc_physinfo(xch, &physinfo) )
+        max_nodes = physinfo.max_node_id + 1;
+
+    return max_nodes;
+}
+
 int xc_get_cpumap_size(xc_interface *xch)
 {
     return (xc_get_max_cpus(xch) + 7) / 8;

diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
index 15bf8d28cb469b772a3756d0d4be856b253ca307..91fbb029793a303524baabc9a2cfd71475956d6e 100644 (file)
--- a/tools/libxc/xenctrl.h
+++ b/tools/libxc/xenctrl.h
@@ -329,6 +329,12 @@ int xc_get_cpumap_size(xc_interface *xch);
 /* allocate a cpumap */
 xc_cpumap_t xc_cpumap_alloc(xc_interface *xch);
 
+ /*
+ * NODEMAP handling
+ */
+/* return maximum number of NUMA nodes the hypervisor supports */
+int xc_get_max_nodes(xc_interface *xch);
+
 /*
  * DOMAIN DEBUGGING FUNCTIONS
  */

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 9f301a90980bc7bf716caa32a465204b72918ef4..2ecdce3efda1e23be1415baf2884f6de5dd92506 100644 (file)
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -3298,6 +3298,75 @@ fail:
     return ret;
 }
 
+libxl_numainfo *libxl_get_numainfo(libxl_ctx *ctx, int *nr)
+{
+    GC_INIT(ctx);
+    xc_numainfo_t ninfo;
+    DECLARE_HYPERCALL_BUFFER(xc_node_to_memsize_t, memsize);
+    DECLARE_HYPERCALL_BUFFER(xc_node_to_memfree_t, memfree);
+    DECLARE_HYPERCALL_BUFFER(uint32_t, node_dists);
+    libxl_numainfo *ret = NULL;
+    int i, j, max_nodes;
+
+    max_nodes = libxl_get_max_nodes(ctx);
+    if (max_nodes == 0)
+    {
+        LIBXL__LOG(ctx, XTL_ERROR, "Unable to determine number of NODES");
+        ret = NULL;
+        goto out;
+    }
+
+    memsize = xc_hypercall_buffer_alloc
+        (ctx->xch, memsize, sizeof(*memsize) * max_nodes);
+    memfree = xc_hypercall_buffer_alloc
+        (ctx->xch, memfree, sizeof(*memfree) * max_nodes);
+    node_dists = xc_hypercall_buffer_alloc
+        (ctx->xch, node_dists, sizeof(*node_dists) * max_nodes * max_nodes);
+    if ((memsize == NULL) || (memfree == NULL) || (node_dists == NULL)) {
+        LIBXL__LOG_ERRNOVAL(ctx, XTL_ERROR, ENOMEM,
+                            "Unable to allocate hypercall arguments");
+        goto fail;
+    }
+
+    set_xen_guest_handle(ninfo.node_to_memsize, memsize);
+    set_xen_guest_handle(ninfo.node_to_memfree, memfree);
+    set_xen_guest_handle(ninfo.node_to_node_distance, node_dists);
+    ninfo.max_node_index = max_nodes - 1;
+    if (xc_numainfo(ctx->xch, &ninfo) != 0) {
+        LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "getting numainfo");
+        goto fail;
+    }
+
+    if (ninfo.max_node_index < max_nodes - 1)
+        max_nodes = ninfo.max_node_index + 1;
+
+    *nr = max_nodes;
+
+    ret = libxl__zalloc(NOGC, sizeof(libxl_numainfo) * max_nodes);
+    for (i = 0; i < max_nodes; i++)
+        ret[i].dists = libxl__calloc(NOGC, max_nodes, sizeof(*node_dists));
+
+    for (i = 0; i < max_nodes; i++) {
+#define V(mem, i) (mem[i] == INVALID_NUMAINFO_ID) ? \
+    LIBXL_NUMAINFO_INVALID_ENTRY : mem[i]
+        ret[i].size = V(memsize, i);
+        ret[i].free = V(memfree, i);
+        ret[i].num_dists = max_nodes;
+        for (j = 0; j < ret[i].num_dists; j++)
+            ret[i].dists[j] = V(node_dists, i * max_nodes + j);
+#undef V
+    }
+
+ fail:
+    xc_hypercall_buffer_free(ctx->xch, memsize);
+    xc_hypercall_buffer_free(ctx->xch, memfree);
+    xc_hypercall_buffer_free(ctx->xch, node_dists);
+
+ out:
+    GC_FREE;
+    return ret;
+}
+
 const libxl_version_info* libxl_get_version_info(libxl_ctx *ctx)
 {
     union {

diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h
index 371b6594344dcb91d3f1f0b72425db8bda3722ce..cb18eda9d56810670600e8d73b8c8bd860b336a5 100644 (file)
--- a/tools/libxl/libxl.h
+++ b/tools/libxl/libxl.h
@@ -532,6 +532,9 @@ int libxl_domain_preserve(libxl_ctx *ctx, uint32_t domid, libxl_domain_create_in
 /* get max. number of cpus supported by hypervisor */
 int libxl_get_max_cpus(libxl_ctx *ctx);
 
+/* get max. number of NUMA nodes supported by hypervisor */
+int libxl_get_max_nodes(libxl_ctx *ctx);
+
 int libxl_domain_rename(libxl_ctx *ctx, uint32_t domid,
                         const char *old_name, const char *new_name);
 
@@ -604,6 +607,10 @@ void libxl_vminfo_list_free(libxl_vminfo *list, int nb_vm);
 libxl_cputopology *libxl_get_cpu_topology(libxl_ctx *ctx, int *nb_cpu_out);
 void libxl_cputopology_list_free(libxl_cputopology *, int nb_cpu);
 
+#define LIBXL_NUMAINFO_INVALID_ENTRY (~(uint32_t)0)
+libxl_numainfo *libxl_get_numainfo(libxl_ctx *ctx, int *nr);
+void libxl_numainfo_list_free(libxl_numainfo *, int nr);
+
 libxl_vcpuinfo *libxl_list_vcpu(libxl_ctx *ctx, uint32_t domid,
                                 int *nb_vcpu, int *nr_vcpus_out);
 void libxl_vcpuinfo_list_free(libxl_vcpuinfo *, int nr_vcpus);

diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index 00947e187527d21170cf4dc2274c1d653b3e65e4..2735ebd82a86bbf44908e58306351e02d2e28e53 100644 (file)
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -433,6 +433,15 @@ libxl_physinfo = Struct("physinfo", [
     ("cap_hvm_directio", bool),
     ], dir=DIR_OUT)
 
+# NUMA node characteristics: size and free are how much memory it has, and how
+# much of it is free, respectively. dists is an array of distances from this
+# node to each other node.
+libxl_numainfo = Struct("numainfo", [
+    ("size", uint64),
+    ("free", uint64),
+    ("dists", Array(uint32, "num_dists")),
+    ], dir=DIR_OUT)
+
 libxl_cputopology = Struct("cputopology", [
     ("core", uint32),
     ("socket", uint32),

diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
index f69a24c2679f590913a56844e165a26fcb40e97e..29f430d97788f79684a227d9b7c9da38494ee600 100644 (file)
--- a/tools/libxl/libxl_utils.c
+++ b/tools/libxl/libxl_utils.c
@@ -572,6 +572,11 @@ int libxl_get_max_cpus(libxl_ctx *ctx)
     return xc_get_max_cpus(ctx->xch);
 }
 
+int libxl_get_max_nodes(libxl_ctx *ctx)
+{
+    return xc_get_max_nodes(ctx->xch);
+}
+
 int libxl__enum_from_string(const libxl_enum_string_table *t,
                             const char *s, int *e)
 {
@@ -594,6 +599,14 @@ void libxl_cputopology_list_free(libxl_cputopology *list, int nr)
     free(list);
 }
 
+void libxl_numainfo_list_free(libxl_numainfo *list, int nr)
+{
+    int i;
+    for (i = 0; i < nr; i++)
+        libxl_numainfo_dispose(&list[i]);
+    free(list);
+}
+
 void libxl_vcpuinfo_list_free(libxl_vcpuinfo *list, int nr)
 {
     int i;

diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
index 88ec803cfd97f2eddccda8be42dc3119561288a6..3225b2ae42519af55ef2b24725c27d44e3e8451d 100644 (file)
--- a/xen/include/public/sysctl.h
+++ b/xen/include/public/sysctl.h
@@ -484,6 +484,7 @@ typedef struct xen_sysctl_topologyinfo xen_sysctl_topologyinfo_t;
 DEFINE_XEN_GUEST_HANDLE(xen_sysctl_topologyinfo_t);
 
 /* XEN_SYSCTL_numainfo */
+#define INVALID_NUMAINFO_ID (~0U)
 struct xen_sysctl_numainfo {
     /*
      * IN: maximum addressable entry in the caller-provided arrays.