1 files changed, 86 insertions, 0 deletions
diff --git a/malloc-hugepage-0007-malloc-Enable-huge-page-support-on-main-arena.patch b/malloc-hugepage-0007-malloc-Enable-huge-page-support-on-main-arena.patch
new file mode 100644
index 0000000..fa5c9db
--- /dev/null
+++ b/malloc-hugepage-0007-malloc-Enable-huge-page-support-on-main-arena.patch
@@ -0,0 +1,86 @@
+From 0f982c182760bd7689769ee7590df592d0a132c0 Mon Sep 17 00:00:00 2001
+From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
+Date: Mon, 30 Aug 2021 14:01:00 -0300
+Subject: [PATCH 7/7] malloc: Enable huge page support on main arena
+
+This patch adds support huge page support on main arena allocation,
+enable with tunable glibc.malloc.hugetlb=2.  The patch essentially
+disable the __glibc_morecore() sbrk() call (similar when memory
+tag does when sbrk() call does not support it) and fallback to
+default page size if the memory allocation fails.
+
+Checked on x86_64-linux-gnu.
+
+Reviewed-by: DJ Delorie <dj@redhat.com>
+---
+ malloc/arena.c    |  4 ++++
+ malloc/malloc.c   | 12 ++++++++++--
+ malloc/morecore.c |  4 ----
+ 3 files changed, 14 insertions(+), 6 deletions(-)
+
+diff --git a/malloc/arena.c b/malloc/arena.c
+index e1852f8597..3ed4ef3f05 100644
+--- a/malloc/arena.c
++++ b/malloc/arena.c
+@@ -364,6 +364,10 @@ ptmalloc_init (void)
+ # endif
+   TUNABLE_GET (mxfast, size_t, TUNABLE_CALLBACK (set_mxfast));
+   TUNABLE_GET (hugetlb, size_t, TUNABLE_CALLBACK (set_hugetlb));
++  if (mp_.hp_pagesize > 0)
++    /* Force mmap for main arena instead of sbrk, so hugepages are explicitly
++       used.  */
++    __always_fail_morecore = true;
+ #else
+   if (__glibc_likely (_environ != NULL))
+     {
+diff --git a/malloc/malloc.c b/malloc/malloc.c
+index 32050be4cc..b67f2c84ee 100644
+--- a/malloc/malloc.c
++++ b/malloc/malloc.c
+@@ -2741,8 +2741,16 @@ sysmalloc (INTERNAL_SIZE_T nb, mstate av)
+              segregated mmap region.
+            */
+ 
+-	  char *mbrk = sysmalloc_mmap_fallback (&size, nb, old_size, pagesize,
+-						MMAP_AS_MORECORE_SIZE, 0, av);
++	  char *mbrk = MAP_FAILED;
++#if HAVE_TUNABLES
++	  if (mp_.hp_pagesize > 0)
++	    mbrk = sysmalloc_mmap_fallback (&size, nb, old_size,
++					    mp_.hp_pagesize, mp_.hp_pagesize,
++					    mp_.hp_flags, av);
++#endif
++	  if (mbrk == MAP_FAILED)
++	    mbrk = sysmalloc_mmap_fallback (&size, nb, old_size, pagesize,
++					    MMAP_AS_MORECORE_SIZE, 0, av);
+ 	  if (mbrk != MAP_FAILED)
+ 	    {
+ 	      /* We do not need, and cannot use, another sbrk call to find end */
+diff --git a/malloc/morecore.c b/malloc/morecore.c
+index 8168ef158c..004cd3ead4 100644
+--- a/malloc/morecore.c
++++ b/malloc/morecore.c
+@@ -15,9 +15,7 @@
+    License along with the GNU C Library; if not, see
+    <https://www.gnu.org/licenses/>.  */
+ 
+-#if defined(SHARED) || defined(USE_MTAG)
+ static bool __always_fail_morecore = false;
+-#endif
+ 
+ /* Allocate INCREMENT more bytes of data space,
+    and return the start of data space, or NULL on errors.
+@@ -25,10 +23,8 @@ static bool __always_fail_morecore = false;
+ void *
+ __glibc_morecore (ptrdiff_t increment)
+ {
+-#if defined(SHARED) || defined(USE_MTAG)
+   if (__always_fail_morecore)
+     return NULL;
+-#endif
+ 
+   void *result = (void *) __sbrk (increment);
+   if (result == (void *) -1)
+-- 
+2.33.0
+