Add opt.thp which allows explicit hugepage usage.

"always" marks all user mappings as MADV_HUGEPAGE; while "never" marks all
mappings as MADV_NOHUGEPAGE. The default setting "default" does not change any
settings.  Note that all the madvise calls are part of the default extent hooks
by design, so that customized extent hooks have complete control over the
mappings including hugepage settings.

1 files changed, 14 insertions, 2 deletions

diff --git a/include/jemalloc/internal/pages.h b/include/jemalloc/internal/pages.h
index dff20515..7dae633a 100644
--- a/include/jemalloc/internal/pages.h
+++ b/include/jemalloc/internal/pages.h
@@ -58,8 +58,19 @@ static const bool pages_can_purge_forced =
 #endif
     ;
 
-/* Whether transparent huge page state is "madvise". */
-extern bool thp_state_madvise;
+typedef enum {
+	thp_mode_default       = 0, /* Do not change hugepage settings. */
+	thp_mode_always        = 1, /* Always set MADV_HUGEPAGE. */
+	thp_mode_never         = 2, /* Always set MADV_NOHUGEPAGE. */
+
+	thp_mode_names_limit   = 3, /* Used for option processing. */
+	thp_mode_not_supported = 3  /* No THP support detected. */
+} thp_mode_t;
+
+#define THP_MODE_DEFAULT thp_mode_default
+extern thp_mode_t opt_thp;
+extern thp_mode_t init_system_thp_mode; /* Initial system wide state. */
+extern const char *thp_mode_names[];
 
 void *pages_map(void *addr, size_t size, size_t alignment, bool *commit);
 void pages_unmap(void *addr, size_t size);
@@ -72,5 +83,6 @@ bool pages_nohuge(void *addr, size_t size);
 bool pages_dontdump(void *addr, size_t size);
 bool pages_dodump(void *addr, size_t size);
 bool pages_boot(void);
+void pages_set_thp_state (void *ptr, size_t size);
 
 #endif /* JEMALLOC_INTERNAL_PAGES_EXTERNS_H */