adding option to disable thp on linux/android

rpmalloc/rpmalloc.c

@@ -2095,6 +2095,11 @@ rpmalloc_initialize(rpmalloc_interface_t* memory_interface) {
 	if (global_config.enable_huge_pages || global_config.page_size > (256 * 1024))
 		global_config.disable_decommit = 1;
 
+#if defined(__linux__) || defined(__ANDROID__)
+	if (global_config.disable_thp)
+		(void)prctl(PR_SET_THP_DISABLE, 1, 0, 0, 0);
+#endif
+
 #ifdef _WIN32
 	fls_key = FlsAlloc(&rpmalloc_thread_destructor);
 #else

rpmalloc/rpmalloc.h

@@ -187,6 +187,13 @@ typedef struct rpmalloc_config_t {
 	//  when process exits, but if using rpmalloc in a dynamic library you might want to unmap
 	//  all pages when the dynamic library unloads to avoid process memory leaks and bloat.
 	int unmap_on_finalize;
+#if defined(__linux__) || defined(__ANDROID__)
+	///! Allows to disable the Transparent Huge Page feature on Linux on a process basis,
+	///  rather than enabling/disabling system-wise (done via /sys/kernel/mm/transparent_hugepage/enabled).
+	///  It can possibly improve performance and reduced allocation overhead in some contexts, albeit
+	///  THP is usually enabled by default.
+	int disable_thp;
+#endif
 } rpmalloc_config_t;
 
 //! Initialize allocator