ggc-page.c (release_pages): Output statistics when !quiet_flag.

	* ggc-page.c (release_pages): Output statistics when !quiet_flag.
	(ggc_collect): Dump later to not interfere with release_page dump.
	(ggc_trim): New function.
	* ggc-none.c (ggc_trim): New.
	* ggc.h (ggc_trim): Declare.

	* lto.c (lto_wpa_write_files): Call ggc_trim.

From-SVN: r276878

6 files changed, 60 insertions, 6 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e250c9d55d0..a73fe2074ed 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2019-10-11  Jan Hubicka  <hubicka@ucw.cz>
+
+	* ggc-page.c (release_pages): Output statistics when !quiet_flag.
+	(ggc_collect): Dump later to not interfere with release_page dump.
+	(ggc_trim): New function.
+	* ggc-none.c (ggc_trim): New.
+	* ggc.h (ggc_trim): Declare.
+
 2019-10-11  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/92066
diff --git a/gcc/ggc-none.c b/gcc/ggc-none.c
index 6edec27868c..737429f9e49 100644
--- a/gcc/ggc-none.c
+++ b/gcc/ggc-none.c
@@ -72,3 +72,8 @@ void
 ggc_grow (void)
 {
 }
+
+void
+ggc_trim (void)
+{
+}
diff --git a/gcc/ggc-page.c b/gcc/ggc-page.c
index 220f20c5cfe..4560206ac2e 100644
--- a/gcc/ggc-page.c
+++ b/gcc/ggc-page.c
@@ -529,7 +529,6 @@ static void clear_page_group_in_use (page_group *, char *);
 #endif
 static struct page_entry * alloc_page (unsigned);
 static void free_page (struct page_entry *);
-static void release_pages (void);
 static void clear_marks (void);
 static void sweep_pages (void);
 static void ggc_recalculate_in_use_p (page_entry *);
@@ -1016,6 +1015,8 @@ free_page (page_entry *entry)
 static void
 release_pages (void)
 {
+  size_t n1 = 0;
+  size_t n2 = 0;
 #ifdef USING_MADVISE
   page_entry *p, *start_p;
   char *start;
@@ -1061,6 +1062,7 @@ release_pages (void)
           else
             G.free_pages = p;
           G.bytes_mapped -= mapped_len;
+	  n1 += len;
 	  continue;
         }
       prev = newprev;
@@ -1092,6 +1094,7 @@ release_pages (void)
       /* Don't count those pages as mapped to not touch the garbage collector
          unnecessarily. */
       G.bytes_mapped -= len;
+      n2 += len;
       while (start_p != p)
         {
           start_p->discarded = true;
@@ -1124,6 +1127,7 @@ release_pages (void)
 	}
 
       munmap (start, len);
+      n1 += len;
       G.bytes_mapped -= len;
     }
 
@@ -1152,10 +1156,20 @@ release_pages (void)
 	*gp = g->next;
 	G.bytes_mapped -= g->alloc_size;
 	free (g->allocation);
+	n1 += g->alloc_size;
       }
     else
       gp = &g->next;
 #endif
+  if (!quiet_flag && (n1 || n2))
+    {
+      fprintf (stderr, " {GC");
+      if (n1)
+	fprintf (stderr, " released %luk", (unsigned long)(n1 / 1024));
+      if (n2)
+	fprintf (stderr, " madv_dontneed %luk", (unsigned long)(n2 / 1024));
+      fprintf (stderr, "}");
+    }
 }
 
 /* This table provides a fast way to determine ceil(log_2(size)) for
@@ -2178,19 +2192,22 @@ ggc_collect (void)
     return;
 
   timevar_push (TV_GC);
-  if (!quiet_flag)
-    fprintf (stderr, " {GC %luk -> ", (unsigned long) G.allocated / 1024);
   if (GGC_DEBUG_LEVEL >= 2)
     fprintf (G.debug_file, "BEGIN COLLECTING\n");
 
   /* Zero the total allocated bytes.  This will be recalculated in the
      sweep phase.  */
+  size_t allocated = G.allocated;
   G.allocated = 0;
 
   /* Release the pages we freed the last time we collected, but didn't
      reuse in the interim.  */
   release_pages ();
 
+  /* Output this later so we do not interfere with release_pages.  */
+  if (!quiet_flag)
+    fprintf (stderr, " {GC %luk -> ", (unsigned long) allocated / 1024);
+
   /* Indicate that we've seen collections at this context depth.  */
   G.context_depth_collections = ((unsigned long)1 << (G.context_depth + 1)) - 1;
 
@@ -2221,9 +2238,25 @@ ggc_collect (void)
     fprintf (G.debug_file, "END COLLECTING\n");
 }
 
-/* Assume that all GGC memory is reachable and grow the limits for next collection.
-   With checking, trigger GGC so -Q compilation outputs how much of memory really is
-   reachable.  */
+/* Return free pages to the system.  */
+
+void
+ggc_trim ()
+{
+  timevar_push (TV_GC);
+  G.allocated = 0;
+  sweep_pages ();
+  release_pages ();
+  if (!quiet_flag)
+    fprintf (stderr, " {GC trimmed to %luk, %luk mapped}",
+	     (unsigned long) G.allocated / 1024,
+	     (unsigned long) G.bytes_mapped / 1024);
+  timevar_pop (TV_GC);
+}
+
+/* Assume that all GGC memory is reachable and grow the limits for next
+   collection.  With checking, trigger GGC so -Q compilation outputs how much
+   of memory really is reachable.  */
 
 void
 ggc_grow (void)
diff --git a/gcc/ggc.h b/gcc/ggc.h
index 60273f2e57d..31606dc843f 100644
--- a/gcc/ggc.h
+++ b/gcc/ggc.h
@@ -243,6 +243,9 @@ extern const char *ggc_alloc_string (const char *contents, int length
    function is called, not during allocations.  */
 extern void ggc_collect	(void);
 
+/* Return unused memory pages to the system.  */
+extern void ggc_trim (void);
+
 /* Assume that all GGC memory is reachable and grow the limits for next collection. */
 extern void ggc_grow (void);
 
diff --git a/gcc/lto/ChangeLog b/gcc/lto/ChangeLog
index 5fd02dff7cd..5ad79e821ad 100644
--- a/gcc/lto/ChangeLog
+++ b/gcc/lto/ChangeLog
@@ -1,5 +1,9 @@
 2019-10-11  Jan Hubicka  <hubicka@ucw.cz>
 
+	* lto.c (lto_wpa_write_files): Call ggc_trim.
+
+2019-10-11  Jan Hubicka  <hubicka@ucw.cz>
+
 	* lto.c (lto_wpa_write_files): Prepare all bodies for streaming.
 
 2019-10-10  Richard Biener  <rguenther@suse.de>
diff --git a/gcc/lto/lto.c b/gcc/lto/lto.c
index f7452c232fe..5aa143859d5 100644
--- a/gcc/lto/lto.c
+++ b/gcc/lto/lto.c
@@ -311,6 +311,7 @@ lto_wpa_write_files (void)
     if (gimple_has_body_p (node->decl))
       lto_prepare_function_for_streaming (node);
 
+  ggc_trim ();
   /* Generate a prefix for the LTRANS unit files.  */
   blen = strlen (ltrans_output_list);
   temp_filename = (char *) xmalloc (blen + sizeof ("2147483648.o"));