linux: add support for numa set_mempolicy(2)

mempolicy.c:
- new file
- provides libcrun_set_mempolicy as wrapper to set_mempolicy(2)

mempolicy.h:
- new file
- define libcrun_set_mempolicy

container.c:
- add call to libcrun_set_mempolicy in libcrun_container_run_internal
- populate feature array

container.h:
- add memory_policy_info_s

oci_features.c
- populate json feature array

tests/test_mempolicy.py:
- new file
- add both negative and positive tests for mempolicy.c
- tests will run if hw supports numa or skip

Makefile.am:
- update
- changes verified also with make distcheck

Signed-off-by: Fabio M. Di Nitto <[email protected]>

Author: fabbione

Makefile.am

@@ -67,6 +67,7 @@ libcrun_SOURCES = src/libcrun/utils.c \
 		src/libcrun/linux.c \
 		src/libcrun/mount_flags.c \
 		src/libcrun/scheduler.c \
+		src/libcrun/mempolicy.c \
 		src/libcrun/seccomp.c \
 		src/libcrun/seccomp_notify.c \
 		src/libcrun/signals.c \
@@ -160,7 +161,7 @@ EXTRA_DIST = COPYING COPYING.libcrun README.md NEWS SECURITY.md rpm/crun.spec au
 	src/libcrun/custom-handler.h src/libcrun/io_priority.h \
 	src/libcrun/handlers/handler-utils.h \
 	src/libcrun/linux.h src/libcrun/utils.h src/libcrun/error.h src/libcrun/criu.h \
-	src/libcrun/scheduler.h src/libcrun/status.h src/libcrun/terminal.h \
+	src/libcrun/scheduler.h src/libcrun/mempolicy.h src/libcrun/status.h src/libcrun/terminal.h \
 	src/libcrun/mount_flags.h src/libcrun/intelrdt.h src/libcrun/ring_buffer.h src/libcrun/string_map.h \
 	src/libcrun/net_device.h \
 	crun.1.md crun.1 libcrun.lds \
@@ -225,6 +226,7 @@ PYTHON_TESTS = tests/test_capabilities.py \
 	tests/test_hostname.py \
 	tests/test_limits.py \
 	tests/test_oci_features.py \
+	tests/test_mempolicy.py \
 	tests/test_mounts.py \
 	tests/test_paths.py \
 	tests/test_pid.py \

src/libcrun/container.c

@@ -23,6 +23,7 @@
 #include "container.h"
 #include "utils.h"
 #include "seccomp.h"
+#include "mempolicy.h"
 #ifdef HAVE_SECCOMP
 #  include <seccomp.h>
 #endif
@@ -167,6 +168,22 @@ static char *archs[] = {
   "SCMP_ARCH_X86_64"
 };
 
+static char *mempolicy_modes[] = {
+  "MPOL_DEFAULT",
+  "MPOL_PREFERRED",
+  "MPOL_BIND",
+  "MPOL_INTERLEAVE",
+  "MPOL_LOCAL",
+  "MPOL_PREFERRED_MANY",
+  "MPOL_WEIGHTED_INTERLEAVE"
+};
+
+static char *mempolicy_flags[] = {
+  "MPOL_F_NUMA_BALANCING",
+  "MPOL_F_RELATIVE_NODES",
+  "MPOL_F_STATIC_NODES"
+};
+
 static const char spec_file[] = "\
 {\n\
 	\"ociVersion\": \"1.0.0\",\n\
@@ -2768,6 +2785,10 @@ libcrun_container_run_internal (libcrun_container_t *container, libcrun_context_
 
   umask (0);
 
+  ret = libcrun_set_mempolicy (def, err);
+  if (UNLIKELY (ret < 0))
+    return ret;
+
   ret = setup_seccomp (container, seccomp_bpf_data, &seccomp_gen_ctx, &seccomp_fd, err);
   if (UNLIKELY (ret < 0))
     return ret;
@@ -4324,6 +4345,8 @@ libcrun_container_get_features (libcrun_context_t *context, struct features_info
   size_t num_unsafe_annotations = sizeof (potentially_unsafe_annotations) / sizeof (potentially_unsafe_annotations[0]);
   cleanup_free char **capabilities = NULL;
   size_t num_capabilities = 0;
+  size_t num_mempolicy_modes = sizeof (mempolicy_modes) / sizeof (mempolicy_modes[0]);
+  size_t num_mempolicy_flags = sizeof (mempolicy_flags) / sizeof (mempolicy_flags[0]);
 
   *info = xmalloc0 (sizeof (struct features_info_s));
 
@@ -4374,6 +4397,9 @@ libcrun_container_get_features (libcrun_context_t *context, struct features_info
 
   (*info)->linux.net_devices.enabled = true;
 
+  populate_array_field (&((*info)->linux.memory_policy.mode), mempolicy_modes, num_mempolicy_modes);
+  populate_array_field (&((*info)->linux.memory_policy.flags), mempolicy_flags, num_mempolicy_flags);
+
   // Put the values for mount extensions
   (*info)->linux.mount_ext.idmap.enabled = true;
 

src/libcrun/container.h

@@ -149,6 +149,12 @@ struct mount_ext_info_s
   struct idmap_info_s idmap;
 };
 
+struct memory_policy_info_s
+{
+  char **mode;
+  char **flags;
+};
+
 struct linux_info_s
 {
   char **namespaces;
@@ -160,6 +166,7 @@ struct linux_info_s
   struct mount_ext_info_s mount_ext;
   struct intel_rdt_s intel_rdt;
   struct net_devices_s net_devices;
+  struct memory_policy_info_s memory_policy;
 };
 
 struct annotations_info_s

src/libcrun/mempolicy.c

@@ -0,0 +1,155 @@
+/*
+ * crun - OCI runtime written in C
+ *
+ * Copyright (C) 2017, 2018, 2019 Giuseppe Scrivano <[email protected]>
+ * crun is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * crun is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with crun.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include "linux.h"
+#include "utils.h"
+#include <ocispec/runtime_spec_schema_config_schema.h>
+
+#include <sys/syscall.h>
+#include <unistd.h>
+
+/* follow runc go implementation and redefine everything here */
+/* Policies */
+#define MPOL_DEFAULT 0
+#define MPOL_PREFERRED 1
+#define MPOL_BIND 2
+#define MPOL_INTERLEAVE 3
+#define MPOL_LOCAL 4
+#define MPOL_PREFERRED_MANY 5
+#define MPOL_WEIGHTED_INTERLEAVE 6
+
+/* Flags for set_mempolicy, specified in mode */
+#define MPOL_F_NUMA_BALANCING (1 << 13)
+#define MPOL_F_RELATIVE_NODES (1 << 14)
+#define MPOL_F_STATIC_NODES (1 << 15)
+
+typedef struct
+{
+  const char *name;
+  int value;
+} str2int_map_t;
+
+/* update mpol_mode_map based on numaif.h MPOL_MAX
+ * the warn in mempolicy.c will indicate that an update is required.
+ * MPOL_WEIGHTED_INTERLEAVE has been introduced in MPOL_MAX 7 (kernel 6.9+)
+ * and some distros still has older kernel interfaces */
+str2int_map_t mpol_mode_map[] = {
+  { "MPOL_DEFAULT", MPOL_DEFAULT },
+  { "MPOL_PREFERRED", MPOL_PREFERRED },
+  { "MPOL_BIND", MPOL_BIND },
+  { "MPOL_INTERLEAVE", MPOL_INTERLEAVE },
+  { "MPOL_LOCAL", MPOL_LOCAL },
+  { "MPOL_PREFERRED_MANY", MPOL_PREFERRED_MANY },
+  { "MPOL_WEIGHTED_INTERLEAVE", MPOL_WEIGHTED_INTERLEAVE },
+  { NULL, -1 }
+};
+
+/* flags cannot be tracked the same way as mode */
+str2int_map_t mpol_flag_map[] = {
+  { "MPOL_F_NUMA_BALANCING", MPOL_F_NUMA_BALANCING },
+  { "MPOL_F_RELATIVE_NODES", MPOL_F_RELATIVE_NODES },
+  { "MPOL_F_STATIC_NODES", MPOL_F_STATIC_NODES },
+  { NULL, -1 }
+};
+
+#define MAX_NUMA_NODES 4096
+
+static int
+mpol_str2int (const char *str, const str2int_map_t *map)
+{
+  int idx = 0;
+
+  while (map[idx].name != NULL)
+    {
+      if (! strcmp (map[idx].name, str))
+        {
+          return map[idx].value;
+        }
+      idx++;
+    }
+
+  errno = EINVAL;
+  return -1;
+}
+
+int
+libcrun_set_mempolicy (runtime_spec_schema_config_schema *def, libcrun_error_t *err)
+{
+  runtime_spec_schema_config_linux_memory_policy *memory_policy = NULL;
+  int mpol_mode = 0;
+  int mpol_flag = 0;
+  size_t i = 0;
+  long unsigned int nmask[MAX_NUMA_NODES / (sizeof (unsigned long) * 8)];
+  long unsigned int *nmask_final = NULL;
+  int ret = 0;
+
+  if (def->linux == NULL || def->linux->memory_policy == NULL)
+    {
+      libcrun_debug ("no linux numa mempolicy configuration found");
+      return ret;
+    }
+
+  libcrun_debug ("Initializing linux numa mempolicy");
+
+  memory_policy = def->linux->memory_policy;
+
+  libcrun_debug ("Validating linux numa mempolicy");
+  /* validate memory policy mode */
+  if (! memory_policy->mode)
+    return crun_make_error (err, EINVAL, "linux numa mempolicy mode is missing from the configuration");
+
+  libcrun_debug ("Validating mode: %s", memory_policy->mode);
+  mpol_mode = mpol_str2int (memory_policy->mode, mpol_mode_map);
+  if (mpol_mode < 0)
+    return crun_make_error (err, EINVAL, "Requested linux numa mempolicy mode '%s' is unknown", memory_policy->mode);
+
+  /* validating memory policy flags */
+  libcrun_debug ("Validating mode flags: %zu configured", memory_policy->flags_len);
+  for (i = 0; i < memory_policy->flags_len; i++)
+    {
+      libcrun_debug ("Validating mode flag: %s", memory_policy->flags[i]);
+      mpol_flag = mpol_str2int (memory_policy->flags[i], mpol_flag_map);
+      if (mpol_flag < 0)
+        return crun_make_error (err, EINVAL, "Requested linux numa mempolicy flag '%s' is unknown", memory_policy->flags[i]);
+      mpol_mode = mpol_mode | mpol_flag;
+    }
+
+  /* kernel will take care of validating the nodes */
+  if (memory_policy->nodes)
+    {
+      cleanup_free char *bitmask = NULL;
+      size_t bitmask_size;
+
+      ret = cpuset_string_to_bitmask (memory_policy->nodes, &bitmask, &bitmask_size, err);
+      if (UNLIKELY (ret < 0))
+        return ret;
+
+      if (bitmask_size > sizeof (nmask))
+        return crun_make_error (err, EINVAL, "Requested bitmask bigger than kernel supported bitmask");
+
+      nmask_final = nmask;
+      memset (nmask_final, 0, sizeof (nmask));
+      memcpy (nmask_final, bitmask, bitmask_size);
+    }
+
+  if (syscall (__NR_set_mempolicy, mpol_mode, nmask_final, MAX_NUMA_NODES - 1) < 0)
+    return crun_make_error (err, errno, "set_mempolicy");
+
+  return ret;
+}

src/libcrun/mempolicy.h

@@ -0,0 +1,27 @@
+/*
+ * crun - OCI runtime written in C
+ *
+ * Copyright (C) 2017, 2018, 2019, 2021 Giuseppe Scrivano <[email protected]>
+ * crun is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * crun is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with crun.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MEMPOLICY_H
+#define MEMPOLICY_H
+#include <config.h>
+#include "error.h"
+#include "container.h"
+#include "status.h"
+
+int libcrun_set_mempolicy (runtime_spec_schema_config_schema *def, libcrun_error_t *err);
+
+#endif

src/oci_features.c

@@ -150,6 +150,21 @@ crun_features_add_seccomp_info (yajl_gen json_gen, const struct linux_info_s *li
   yajl_gen_map_close (json_gen);
 }
 
+void
+crun_features_add_mempolicy_info (yajl_gen json_gen, const struct linux_info_s *linux)
+{
+  yajl_gen_string (json_gen, (const unsigned char *) "memoryPolicy", strlen ("memoryPolicy"));
+  yajl_gen_map_open (json_gen);
+
+  if (linux->memory_policy.mode)
+    add_array_to_json (json_gen, "modes", linux->memory_policy.mode);
+
+  if (linux->memory_policy.flags)
+    add_array_to_json (json_gen, "flags", linux->memory_policy.flags);
+
+  yajl_gen_map_close (json_gen);
+}
+
 void
 crun_features_add_apparmor_info (yajl_gen json_gen, const struct linux_info_s *linux)
 {
@@ -219,6 +234,7 @@ crun_features_add_linux_info (yajl_gen json_gen, const struct linux_info_s *linu
   crun_features_add_mount_ext_info (json_gen, linux);
   crun_features_add_intel_rdt (json_gen, linux);
   crun_features_add_net_devices (json_gen, linux);
+  crun_features_add_mempolicy_info (json_gen, linux);
 
   yajl_gen_map_close (json_gen);
 }