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authorPaul Guyot <[email protected]>2010-10-03 18:04:55 +0200
committerRickard Green <[email protected]>2010-11-18 11:42:58 +0100
commit667409afe4f909d18f6e19e6ca5a65a4848e51d6 (patch)
treec52a954b74095a3d7e11f2401e4a8e8ffe50875d /erts/lib_src/common/erl_misc_utils.c
parentf21f0fa7d7ab6d5db573f06191a93aed6477b01b (diff)
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Add support for CPU affinity & topology detection on FreeBSD 8
Diffstat (limited to 'erts/lib_src/common/erl_misc_utils.c')
-rw-r--r--erts/lib_src/common/erl_misc_utils.c257
1 files changed, 257 insertions, 0 deletions
diff --git a/erts/lib_src/common/erl_misc_utils.c b/erts/lib_src/common/erl_misc_utils.c
index 116c9886d8..8c10106d02 100644
--- a/erts/lib_src/common/erl_misc_utils.c
+++ b/erts/lib_src/common/erl_misc_utils.c
@@ -71,6 +71,19 @@
(CPUSET)) != 0 ? -errno : 0)
#define ERTS_MU_SET_THR_AFFINITY__(SETP) \
(sched_setaffinity(0, sizeof(cpu_set_t), (SETP)) != 0 ? -errno : 0)
+#elif defined(HAVE_CPUSET_xETAFFINITY)
+# include <sys/param.h>
+# include <sys/cpuset.h>
+# define ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__
+#define ERTS_MU_GET_PROC_AFFINITY__(CPUINFOP, CPUSET) \
+ (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, -1, \
+ sizeof(cpuset_t), \
+ (CPUSET)) != 0 ? -errno : 0)
+#define ERTS_MU_SET_THR_AFFINITY__(CPUSETP) \
+ (cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, \
+ sizeof(cpuset_t), \
+ (CPUSETP)) != 0 ? -errno : 0)
+# define cpu_set_t cpuset_t
#elif defined(__WIN32__)
# define ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__
# define cpu_set_t DWORD
@@ -100,6 +113,11 @@
# define ERTS_SYS_CPU_PATH "/sys/devices/system/cpu"
#endif
+#ifdef __FreeBSD__
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#endif
+
static int read_topology(erts_cpu_info_t *cpuinfo);
#if defined(ERTS_HAVE_MISC_UTIL_AFFINITY_MASK__)
@@ -1375,6 +1393,245 @@ read_topology(erts_cpu_info_t *cpuinfo)
return res;
}
+#elif defined(__FreeBSD__)
+
+/**
+ * FreeBSD topology detection is based on kern.sched.topology_spec XML as
+ * exposed by the ULE scheduler and described in SMP(4). It is available in
+ * 8.0 and higher.
+ *
+ * Threads are identified in this XML chunk with a THREAD flag. The function
+ * (simplistically) distinguishes cores and processors by the amount of cache
+ * they share (0 => processor, otherwise => core). Nodes are not identified
+ * (ULE doesn't handle NUMA yet, I believe).
+ */
+
+/**
+ * Recursively parse a topology_spec <group> tag.
+ */
+static
+const char* parse_topology_spec_group(erts_cpu_info_t *cpuinfo, const char* xml, int parentCacheLevel, int* processor_p, int* core_p, int* index_procs_p) {
+ int error = 0;
+ int cacheLevel = parentCacheLevel;
+ const char* next_group_start = strstr(xml + 1, "<group");
+ int is_thread_group = 0;
+ const char* next_cache_level;
+ const char* next_thread_flag;
+ const char* next_group_end;
+ const char* next_children;
+ const char* next_children_end;
+
+ /* parse the cache level */
+ next_cache_level = strstr(xml, "cache-level=\"");
+ if (next_cache_level && (next_group_start == NULL || next_cache_level < next_group_start)) {
+ sscanf(next_cache_level, "cache-level=\"%i\"", &cacheLevel);
+ }
+
+ /* parse the threads flag */
+ next_thread_flag = strstr(xml, "THREAD");
+ if (next_thread_flag && (next_group_start == NULL || next_thread_flag < next_group_start))
+ is_thread_group = 1;
+
+ /* Determine if it's a leaf with the position of the next children tag */
+ next_group_end = strstr(xml, "</group>");
+ next_children = strstr(xml, "<children>");
+ next_children_end = strstr(xml, "</children>");
+ if (next_children == NULL || next_group_end < next_children) {
+ do {
+ const char* next_cpu_start;
+ const char* next_cpu_cdata;
+ const char* next_cpu_end;
+ int cpu_str_size;
+ char* cpu_str;
+ char* cpu_crsr;
+ char* brkb;
+ int thread = 0;
+ int index_procs = *index_procs_p;
+
+ next_cpu_start = strstr(xml, "<cpu");
+ if (!next_cpu_start) {
+ error = 1;
+ break;
+ }
+ next_cpu_cdata = strstr(next_cpu_start, ">") + 1;
+ if (!next_cpu_cdata) {
+ error = 1;
+ break;
+ }
+ next_cpu_end = strstr(next_cpu_cdata, "</cpu>");
+ if (!next_cpu_end) {
+ error = 1;
+ break;
+ }
+ cpu_str_size = next_cpu_end - next_cpu_cdata;
+ cpu_str = (char*) malloc(cpu_str_size + 1);
+ memcpy(cpu_str, (const char*) next_cpu_cdata, cpu_str_size);
+ cpu_str[cpu_str_size] = 0;
+ for (cpu_crsr = strtok_r(cpu_str, " \t,", &brkb); cpu_crsr; cpu_crsr = strtok_r(NULL, " \t,", &brkb)) {
+ int cpu_id;
+ if (index_procs >= cpuinfo->configured) {
+ void* t = realloc(cpuinfo->topology, (sizeof(erts_cpu_topology_t) * (index_procs + 1)));
+ if (t) {
+ cpuinfo->topology = t;
+ } else {
+ error = 1;
+ break;
+ }
+ }
+ cpu_id = atoi(cpu_crsr);
+ cpuinfo->topology[index_procs].node = -1;
+ cpuinfo->topology[index_procs].processor = *processor_p;
+ cpuinfo->topology[index_procs].processor_node = -1;
+ cpuinfo->topology[index_procs].core = *core_p;
+ cpuinfo->topology[index_procs].thread = thread;
+ cpuinfo->topology[index_procs].logical = cpu_id;
+ if (is_thread_group) {
+ thread++;
+ } else {
+ *core_p = (*core_p)++;
+ }
+ index_procs++;
+ }
+ *index_procs_p = index_procs;
+ free(cpu_str);
+ } while (0);
+ xml = next_group_end;
+ } else {
+ while (next_group_start != NULL && next_group_start < next_children_end) {
+ xml = parse_topology_spec_group(cpuinfo, next_group_start, cacheLevel, processor_p, core_p, index_procs_p);
+ if (!xml)
+ break;
+ next_group_start = strstr(xml, "<group");
+ next_children_end = strstr(xml, "</children>");
+ }
+ }
+
+ if (cacheLevel == 0) {
+ *core_p = 0;
+ *processor_p = (*processor_p)++;
+ } else {
+ *core_p = (*core_p)++;
+ }
+
+ if (error)
+ xml = NULL;
+
+ return xml;
+}
+
+/**
+ * Parse the topology_spec. Return the number of CPUs or 0 if parsing failed.
+ */
+static
+int parse_topology_spec(erts_cpu_info_t *cpuinfo, const char* xml) {
+ int res = 1;
+ int index_procs = 0;
+ int core = 0;
+ int processor = 0;
+ xml = strstr(xml, "<groups");
+ if (!xml)
+ return -1;
+
+ xml += 7;
+ xml = strstr(xml, "<group");
+ while (xml) {
+ xml = parse_topology_spec_group(cpuinfo, xml, 0, &processor, &core, &index_procs);
+ if (!xml) {
+ res = 0;
+ break;
+ }
+ xml = strstr(xml, "<group");
+ }
+
+ if (res)
+ res = index_procs;
+
+ return res;
+}
+
+static int
+read_topology(erts_cpu_info_t *cpuinfo)
+{
+ int ix;
+ int res = 0;
+ size_t topology_spec_size = 0;
+ void* topology_spec = NULL;
+
+ errno = 0;
+
+ if (cpuinfo->configured < 1)
+ goto error;
+
+ cpuinfo->topology_size = cpuinfo->configured;
+ cpuinfo->topology = malloc(sizeof(erts_cpu_topology_t)
+ * cpuinfo->configured);
+ if (!cpuinfo->topology) {
+ res = -ENOMEM;
+ goto error;
+ }
+
+ for (ix = 0; ix < cpuinfo->configured; ix++) {
+ cpuinfo->topology[ix].node = -1;
+ cpuinfo->topology[ix].processor = -1;
+ cpuinfo->topology[ix].processor_node = -1;
+ cpuinfo->topology[ix].core = -1;
+ cpuinfo->topology[ix].thread = -1;
+ cpuinfo->topology[ix].logical = -1;
+ }
+
+ if (!sysctlbyname("kern.sched.topology_spec", NULL, &topology_spec_size, NULL, 0)) {
+ topology_spec = malloc(topology_spec_size);
+ if (!topology_spec) {
+ res = -ENOMEM;
+ goto error;
+ }
+
+ if (sysctlbyname("kern.sched.topology_spec", topology_spec, &topology_spec_size, NULL, 0)) {
+ goto error;
+ }
+
+ res = parse_topology_spec(cpuinfo, topology_spec);
+ if (!res || res < cpuinfo->online)
+ res = 0;
+ else {
+ cpuinfo->topology_size = res;
+
+ if (cpuinfo->topology_size != cpuinfo->configured) {
+ void *t = realloc(cpuinfo->topology, (sizeof(erts_cpu_topology_t)
+ * cpuinfo->topology_size));
+ if (t)
+ cpuinfo->topology = t;
+ }
+
+ adjust_processor_nodes(cpuinfo, 1);
+
+ qsort(cpuinfo->topology,
+ cpuinfo->topology_size,
+ sizeof(erts_cpu_topology_t),
+ cpu_cmp);
+ }
+ }
+
+error:
+
+ if (res == 0) {
+ cpuinfo->topology_size = 0;
+ if (cpuinfo->topology) {
+ free(cpuinfo->topology);
+ cpuinfo->topology = NULL;
+ }
+ if (errno)
+ res = -errno;
+ else
+ res = -EINVAL;
+ }
+
+ if (topology_spec)
+ free(topology_spec);
+
+ return res;
+}
+
#else
static int