malloc: Remove max_total_mem member form struct malloc_par

2016-02-10  Florian Weimer  <fweimer@redhat.com>

	* malloc/malloc.c (__libc_mallinfo): Update comment.
	(struct malloc_par): Remove max_total_mem member, it was always 0.
	(int_mallinfo): Store 0 into usmblks (no functional change).
	* malloc/hooks.c (struct malloc_state): Document that
	max_total_mem is always 0.
	* malloc/malloc.h (struct mallinfo): Dcoument that usmblks is
	always 0.
	* manual/memory.texi (Statistics of Malloc): Likewise.

diff --git a/malloc/hooks.c b/malloc/hooks.c
index 7a85136..0d2bb96 100644
--- a/malloc/hooks.c
+++ b/malloc/hooks.c
@@ -480,7 +480,7 @@  struct malloc_save_state
   unsigned long mmap_threshold;
   int check_action;
   unsigned long max_sbrked_mem;
-  unsigned long max_total_mem;
+  unsigned long max_total_mem;	/* Always 0, for backwards compatibility.  */
   unsigned int n_mmaps;
   unsigned int max_n_mmaps;
   unsigned long mmapped_mem;
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 86e2a03..1038df4 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -649,8 +649,7 @@  libc_hidden_proto (__libc_mallopt)
 	       have been freed but not use resused or consolidated)
   hblks:     current number of mmapped regions
   hblkhd:    total bytes held in mmapped regions
-  usmblks:   the maximum total allocated space. This will be greater
-		than current total if trimming has occurred.
+  usmblks:   always 0
   fsmblks:   total bytes held in fastbin blocks
   uordblks:  current total allocated space (normal or mmapped)
   fordblks:  total free space
@@ -1743,10 +1742,7 @@  struct malloc_par
 
   /* Statistics */
   INTERNAL_SIZE_T mmapped_mem;
-  /*INTERNAL_SIZE_T  sbrked_mem;*/
-  /*INTERNAL_SIZE_T  max_sbrked_mem;*/
   INTERNAL_SIZE_T max_mmapped_mem;
-  INTERNAL_SIZE_T max_total_mem;  /* only kept for NO_THREADS */
 
   /* First address handed out by MORECORE/sbrk.  */
   char *sbrk_base;
@@ -4665,7 +4661,7 @@  int_mallinfo (mstate av, struct mallinfo *m)
     {
       m->hblks = mp_.n_mmaps;
       m->hblkhd = mp_.mmapped_mem;
-      m->usmblks = mp_.max_total_mem;
+      m->usmblks = 0;
       m->keepcost = chunksize (av->top);
     }
 }
diff --git a/malloc/malloc.h b/malloc/malloc.h
index f65e18a..d95a315 100644
--- a/malloc/malloc.h
+++ b/malloc/malloc.h
@@ -83,7 +83,7 @@  struct mallinfo
   int smblks;   /* number of fastbin blocks */
   int hblks;    /* number of mmapped regions */
   int hblkhd;   /* space in mmapped regions */
-  int usmblks;  /* maximum total allocated space */
+  int usmblks;  /* always 0, preserved for backwards compatibility */
   int fsmblks;  /* space available in freed fastbin blocks */
   int uordblks; /* total allocated space */
   int fordblks; /* total free space */
diff --git a/manual/memory.texi b/manual/memory.texi
index 700555e..3d99147 100644
--- a/manual/memory.texi
+++ b/manual/memory.texi
@@ -1520,7 +1520,7 @@  This is the total number of chunks allocated with @code{mmap}.
 This is the total size of memory allocated with @code{mmap}, in bytes.
 
 @item int usmblks
-This field is unused.
+This field is unused and always 0.
 
 @item int fsmblks
 This field is unused.