From 0654dcc7b9370be6472f306d0a7b5ba9bf2b7962 Mon Sep 17 00:00:00 2001
From: Dave Barach <dave@barachs.net>
Date: Wed, 27 Jun 2018 10:49:17 -0400
Subject: Tune pool_get / pool_put

Stop spending cycles repeatedly tail-trimming the pool free element
bitmap; possibly at the expense of slightly hurting pool_foreach
peformance.

Change-Id: I8a7f3e7b26c71d7496ba9393b2a167dc7f538355
Signed-off-by: Dave Barach <dave@barachs.net>
---
 src/vppinfra/pool.h              | 14 +++++++-----
 src/vppinfra/test_pool_iterate.c | 49 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 56 insertions(+), 7 deletions(-)

diff --git a/src/vppinfra/pool.h b/src/vppinfra/pool.h
index 0f64262abf1..d1a2be9ddcd 100644
--- a/src/vppinfra/pool.h
+++ b/src/vppinfra/pool.h
@@ -201,8 +201,8 @@ do {                                                                    \
       /* Return free element from free list. */                         \
       uword _pool_var (i) = _pool_var (p)->free_indices[_pool_var (l) - 1]; \
       (E) = (P) + _pool_var (i);                                        \
-      _pool_var (p)->free_bitmap =                                      \
-	clib_bitmap_andnoti (_pool_var (p)->free_bitmap, _pool_var (i)); \
+      clib_bitmap_set_no_check (_pool_var (p)->free_bitmap,             \
+                                _pool_var (i), 0);                      \
       _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1;       \
     }                                                                   \
   else                                                                  \
@@ -220,7 +220,8 @@ do {                                                                    \
 		       pool_aligned_header_bytes,                       \
 		       /* align */ (A));                                \
       E = vec_end (P) - 1;                                              \
-    }                                                                   \
+      pool_validate_index (P, vec_len(P)-1);                            \
+    }									\
 } while (0)
 
 /** Allocate an object E from a pool P (unspecified alignment). */
@@ -263,7 +264,7 @@ do {                                                                    \
 ({									\
   pool_header_t * _pool_var (p) = pool_header (P);			\
   uword _pool_var (i) = (E) - (P);					\
-  (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
+  (_pool_var (i) < vec_len (P)) ? clib_bitmap_get_no_check (_pool_var (p)->free_bitmap, _pool_i) : 1; \
 })
 
 /** Use free bitmap to query whether given index is free */
@@ -278,8 +279,9 @@ do {									\
   ASSERT (! pool_is_free (P, E));					\
 									\
   /* Add element to free bitmap and to free list. */			\
-  _pool_var (p)->free_bitmap =						\
-    clib_bitmap_ori (_pool_var (p)->free_bitmap, _pool_var (l));	\
+  clib_bitmap_set_no_check (_pool_var (p)->free_bitmap,                 \
+                            _pool_var (l), 1);                          \
+                                                                        \
   /* Preallocated pool? */                                              \
   if (_pool_var (p)->max_elts)                                          \
     {                                                                   \
diff --git a/src/vppinfra/test_pool_iterate.c b/src/vppinfra/test_pool_iterate.c
index 27ce4bb37b7..406a2a577c2 100644
--- a/src/vppinfra/test_pool_iterate.c
+++ b/src/vppinfra/test_pool_iterate.c
@@ -28,17 +28,45 @@ main (int argc, char *argv[])
 {
   int i;
   uword next;
+  u32 last_len = 0;
   u32 *tp = 0;
   u32 *junk;
 
   for (i = 0; i < 70; i++)
-    pool_get (tp, junk);
+    {
+      pool_get (tp, junk);
+      if (vec_len (tp) > last_len)
+	{
+	  last_len = vec_len (tp);
+	  fformat (stdout, "vec_len (tp) now %d\n", last_len);
+	}
+    }
 
   (void) junk;			/* compiler warning */
 
   pool_put_index (tp, 1);
   pool_put_index (tp, 65);
 
+  for (i = 0; i < 70; i++)
+    {
+      int is_free;
+
+      is_free = pool_is_free_index (tp, i);
+
+      if (is_free == 0)
+	{
+	  if (i == 1 || i == 65)
+	    clib_warning ("oops, free index %d reported busy", i);
+	}
+      else
+	{
+	  if (i != 1 && i != 65)
+	    clib_warning ("oops, busy index %d reported free", i);
+	}
+    }
+
+  fformat (stdout, "vec_len (tp) is %d\n", vec_len (tp));
+
   next = ~0;
   do
     {
@@ -47,6 +75,25 @@ main (int argc, char *argv[])
     }
   while (next != ~0);
 
+  /* *INDENT-OFF* */
+  pool_foreach (junk, tp,
+  ({
+    int is_free;
+
+    is_free = pool_is_free_index (tp, junk - tp);
+      if (is_free == 0)
+        {
+          if (i == 1 || i == 65)
+            clib_warning ("oops, free index %d reported busy", i);
+        }
+      else
+        {
+          if (i != 1 && i != 65)
+            clib_warning ("oops, busy index %d reported free", i);
+        }
+  }));
+  /* *INDENT-ON* */
+
   return 0;
 }
 
-- 
cgit 1.2.3-korg