ggml-cpu: fix reported free memory

Author: JohannesGaessler

ggml/src/ggml-cpu/ggml-cpu.cpp

@@ -343,13 +343,14 @@ static void ggml_backend_cpu_device_get_memory(ggml_backend_dev_t dev, size_t *
     status.dwLength = sizeof(status);
     GlobalMemoryStatusEx(&status);
     *total = status.ullTotalPhys;
-    *free = status.ullAvailPhys;
+    *free  = status.ullAvailPhys;
 #else
-    long pages = sysconf(_SC_PHYS_PAGES);
-    long page_size = sysconf(_SC_PAGE_SIZE);
-    *total = pages * page_size;
-    *free = *total;
-#endif
+    const long pages_total = sysconf(_SC_PHYS_PAGES);
+    const long pages_free  = sysconf(_SC_AVPHYS_PAGES);
+    const long page_size   = sysconf(_SC_PAGE_SIZE);
+    *total = pages_total * page_size;
+    *free  = pages_free  * page_size;
+#endif // _WIN32
 
     GGML_UNUSED(dev);
 }