From d8c969c521efbd38df526f085db32c605661e2d1 Mon Sep 17 00:00:00 2001

Message-Id: <d8c969c521efbd38df526f085db32c605661e2d1@dist-git>

From: Michal Privoznik <mprivozn@redhat.com>

Date: Tue, 7 Mar 2023 14:05:27 +0100

Subject: [PATCH] virnuma: Introduce virNumaCPUSetToNodeset()

So far, we have a function that expands given list of NUMA nodes

into list of CPUs. But soon, we are going to need the inverse -

expand list of CPUs into list of NUMA nodes. Introduce

virNumaCPUSetToNodeset() for that.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

Reviewed-by: Kristina Hanicova <khanicov@redhat.com>

Reviewed-by: Andrea Bolognani <abologna@redhat.com>

(cherry picked from commit b6cfd348e9fd1c748481416b1ef42b482db4b4cb)

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2185039

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

---

 src/libvirt_private.syms |  2 ++

 src/util/virnuma.c       | 59 ++++++++++++++++++++++++++++++++++++++++

 src/util/virnuma.h       |  3 ++

 3 files changed, 64 insertions(+)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index e20421e7cd..28a6efda8f 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -2961,6 +2961,7 @@ virNodeSuspendGetTargetMask;

 # util/virnuma.h

+virNumaCPUSetToNodeset;

 virNumaGetAutoPlacementAdvice;

 virNumaGetDistances;

 virNumaGetHostMemoryNodeset;

@@ -2968,6 +2969,7 @@ virNumaGetMaxCPUs;

 virNumaGetMaxNode;

 virNumaGetNodeCPUs;

 virNumaGetNodeMemory;

+virNumaGetNodeOfCPU;

 virNumaGetPageInfo;

 virNumaGetPages;

 virNumaIsAvailable;

diff --git a/src/util/virnuma.c b/src/util/virnuma.c

index dae0827c65..4a15bf32c8 100644

--- a/src/util/virnuma.c

+++ b/src/util/virnuma.c

@@ -311,6 +311,22 @@ virNumaGetNodeCPUs(int node,

 # undef MASK_CPU_ISSET

 # undef n_bits

+

+/**

+ * virNumaGetNodeOfCPU:

+ * @cpu: CPU ID

+ *

+ * For given @cpu, return NUMA node which it belongs to.

+ *

+ * Returns: NUMA node # on success,

+ *          -1 on failure (with errno set).

+ */

+int

+virNumaGetNodeOfCPU(int cpu)

+{

+    return numa_node_of_cpu(cpu);

+}

+

 #else /* !WITH_NUMACTL */

 int

@@ -366,6 +382,14 @@ virNumaGetNodeCPUs(int node G_GNUC_UNUSED,

     return -1;

 }

+int

+virNumaGetNodeOfCPU(int cpu G_GNUC_UNUSED)

+{

+    errno = ENOSYS;

+    return -1;

+}

+

+

 #endif /* !WITH_NUMACTL */

 /**

@@ -990,6 +1014,41 @@ virNumaGetHostMemoryNodeset(void)

 }

+/**

+ * virNumaCPUSetToNodeset:

+ * @cpuset: bitmap containing a set of CPUs

+ * @nodeset: returned bitmap containing a set of NUMA nodes

+ *

+ * Convert a set of CPUs to set of NUMA nodes that contain the CPUs.

+ *

+ * Returns: 0 on success,

+ *          -1 on failure (with error reported)

+ */

+int

+virNumaCPUSetToNodeset(virBitmap *cpuset,

+                       virBitmap **nodeset)

+{

+    g_autoptr(virBitmap) nodes = virBitmapNew(0);

+    ssize_t pos = -1;

+

+    while ((pos = virBitmapNextSetBit(cpuset, pos)) >= 0) {

+        int node = virNumaGetNodeOfCPU(pos);

+

+        if (node < 0) {

+            virReportSystemError(errno,

+                                 _("Unable to get NUMA node of cpu %zd"),

+                                 pos);

+            return -1;

+        }

+

+        virBitmapSetBitExpand(nodes, node);

+    }

+

+    *nodeset = g_steal_pointer(&nodes);

+    return 0;

+}

+

+

 /**

  * virNumaNodesetToCPUset:

  * @nodeset: bitmap containing a set of NUMA nodes

diff --git a/src/util/virnuma.h b/src/util/virnuma.h

index c35acd47cb..2c30ef4e31 100644

--- a/src/util/virnuma.h

+++ b/src/util/virnuma.h

@@ -45,7 +45,10 @@ int virNumaGetNodeMemory(int node,

 unsigned int virNumaGetMaxCPUs(void) G_NO_INLINE;

+int virNumaGetNodeOfCPU(int cpu);

 int virNumaGetNodeCPUs(int node, virBitmap **cpus) G_NO_INLINE;

+int virNumaCPUSetToNodeset(virBitmap *cpuset,

+                           virBitmap **nodeset);

 int virNumaNodesetToCPUset(virBitmap *nodeset,

                            virBitmap **cpuset);

-- 

2.40.0