Implement opt.cache_oblivious.

Keep config.cache_oblivious for now to remain backward-compatible.

include/jemalloc/internal/jemalloc_internal_externs.h

@@ -33,6 +33,7 @@ extern zero_realloc_action_t opt_zero_realloc_action;
 extern malloc_init_t malloc_init_state;
 extern const char *zero_realloc_mode_names[];
 extern atomic_zu_t zero_realloc_count;
+extern bool opt_cache_oblivious;
 
 /* Number of CPUs. */
 extern unsigned ncpus;

include/jemalloc/internal/prof_inlines.h

@@ -223,7 +223,7 @@ prof_sample_align(size_t orig_align) {
 	 * w/o metadata lookup.
 	 */
 	assert(opt_prof);
-	return (config_cache_oblivious && orig_align < PAGE) ? PAGE :
+	return (opt_cache_oblivious && orig_align < PAGE) ? PAGE :
 	    orig_align;
 }
 

include/jemalloc/internal/sz.h

@@ -45,15 +45,13 @@ extern size_t sz_index2size_tab[SC_NSIZES];
  */
 extern uint8_t sz_size2index_tab[];
 
-static const size_t sz_large_pad =
-#ifdef JEMALLOC_CACHE_OBLIVIOUS
-    PAGE
-#else
-    0
-#endif
-    ;
+/*
+ * Padding for large allocations: PAGE when opt_cache_oblivious == true (to
+ * enable cache index randomization); 0 otherwise.
+ */
+extern size_t sz_large_pad;
 
-extern void sz_boot(const sc_data_t *sc_data);
+extern void sz_boot(const sc_data_t *sc_data, bool cache_oblivious);
 
 JEMALLOC_ALWAYS_INLINE pszind_t
 sz_psz2ind(size_t psz) {