rewrite of swiss, swiss will not be public but l4 specific

src/Nitload.Native/nif-src/thread.linux.c

@@ -27,8 +27,11 @@ typedef struct nif_linux_max_context {
 } nif_linux_max_context;
 
 typedef struct nif_linux_fill_cpu_context {
-        uint64_t *internal;
-        uint32_t *global;
+        uint32_t *processor_group_ids;
+        uint32_t *socket_ids;
+        uint32_t *cpu_indices;
+        uint32_t *numa_node_ids;
+        int numa_id;
         int index;
 } nif_linux_fill_cpu_context;
 
@@ -118,14 +121,37 @@ static int nif_linux_track_max_id(int value, void *context)
         return 1;
 }
 
+static int nif_linux_read_socket_id(int cpu_id, uint32_t *socket_id)
+{
+        char path[160];
+        char buffer[64];
+        char *end = NULL;
+        long parsed_value;
+        snprintf(path, sizeof(path),
+                 "/sys/devices/system/cpu/cpu%d/topology/physical_package_id", cpu_id);
+        if (!nif_linux_read_first_line(path, buffer, sizeof(buffer)))
+                return 0;
+
+        errno = 0;
+        parsed_value = strtol(buffer, &end, 10);
+        if (end == buffer || errno == ERANGE || parsed_value < 0 || parsed_value > UINT32_MAX)
+                return 0;
+
+        *socket_id = (uint32_t)parsed_value;
+        return 1;
+}
+
 static int nif_linux_fill_cpu_id(int value, void *context)
 {
         nif_linux_fill_cpu_context *fill_context = (nif_linux_fill_cpu_context *)context;
+        uint32_t socket_id = 0;
+        if (!nif_linux_read_socket_id(value, &socket_id))
+                return 0;
 
-        if (fill_context->internal != NULL)
-                fill_context->internal[fill_context->index] = (uint64_t)fill_context->index;
-        if (fill_context->global != NULL)
-                fill_context->global[fill_context->index] = (uint32_t)value;
+        fill_context->processor_group_ids[fill_context->index] = 0u;
+        fill_context->socket_ids[fill_context->index] = socket_id;
+        fill_context->cpu_indices[fill_context->index] = (uint32_t)value;
+        fill_context->numa_node_ids[fill_context->index] = (uint32_t)fill_context->numa_id;
 
         fill_context->index++;
         return 1;
@@ -211,12 +237,14 @@ static int nif_linux_populate_writable_mapping(void *address, size_t size)
 #endif
 }
 
-/* Pin the calling thread to a single logical processor.
- * core_id >= 0 : bind to that logical processor (global index, across groups).
- * core_id <  0 : clear affinity constraint within the current group. */
-NIF_API void NIF_DECL nif_set_thread_affinity(int core_id, int numa_id)
+/* Linux has no Windows-style processor groups; processor_group_id is ignored. */
+NIF_API void NIF_DECL nif_set_thread_affinity(int cpu_index, int processor_group_id)
 {
-        int cpu_count = (int)sysconf(_SC_NPROCESSORS_ONLN);
+        (void)processor_group_id;
+
+        int cpu_count = (int)sysconf(_SC_NPROCESSORS_CONF);
+        if (cpu_index >= cpu_count)
+                cpu_count = cpu_index + 1;
         if (cpu_count <= 0)
                 return;
 
@@ -227,11 +255,11 @@ NIF_API void NIF_DECL nif_set_thread_affinity(int core_id, int numa_id)
 
         CPU_ZERO_S(size, set);
 
-        if (core_id < 0) {
+        if (cpu_index < 0) {
                 for (int i = 0; i < cpu_count; i++)
                         CPU_SET_S((int)i, size, set);
         } else {
-                CPU_SET_S(core_id, size, set);
+                CPU_SET_S(cpu_index, size, set);
         }
 
         pthread_setaffinity_np(pthread_self(), size, set);
@@ -264,9 +292,14 @@ NIF_API int NIF_DECL nif_get_numa_overall(int *out_numa_count, int *count_of_eac
         return 1;
 }
 
-NIF_API int NIF_DECL nif_get_numa_each(int numa_id, uint64_t *internal, uint32_t *global)
+NIF_API int NIF_DECL nif_get_numa_each(int numa_id,
+                                      uint32_t *processor_group_ids,
+                                      uint32_t *socket_ids,
+                                      uint32_t *cpu_indices,
+                                      uint32_t *numa_node_ids)
 {
-        if (numa_id < 0)
+        if (numa_id < 0 || processor_group_ids == NULL || socket_ids == NULL ||
+            cpu_indices == NULL || numa_node_ids == NULL)
                 return 0;
 
         char path[128];
@@ -275,7 +308,14 @@ NIF_API int NIF_DECL nif_get_numa_each(int numa_id, uint64_t *internal, uint32_t
         if (!nif_linux_read_first_line(path, buffer, sizeof(buffer)))
                 return 0;
 
-        nif_linux_fill_cpu_context fill_context = { internal, global, 0 };
+        nif_linux_fill_cpu_context fill_context = {
+                processor_group_ids,
+                socket_ids,
+                cpu_indices,
+                numa_node_ids,
+                numa_id,
+                0
+        };
         return nif_linux_visit_id_list(buffer, nif_linux_fill_cpu_id, &fill_context);
 }