[Mesa-dev] [PATCH 1/2] util: inline u_vector.c within the header

Emil Velikov emil.l.velikov at gmail.com
Fri Aug 25 20:20:23 UTC 2017


From: Emil Velikov <emil.velikov at collabora.com>

Inlining the implementation does not cause additional overhead in
terms of build time while the binary is increased only marginally (~1k)

At the same time the compiler should be able to optimise better, although
this is not a path where we'll notice much difference.

Use a local u_is_power_of_two to avoid pulling u_math.h. Latter of
which would require updating 5+ locations to have an extra -I directive.

Doing this will allow us to address a unrelated issue, as mentioned in
the report below.

Cc: "17.2" <mesa-stable at lists.freedesktop.org>
Cc: Daniel Stone <daniels at collabora.com>
Cc: Jason Ekstrand <jason at jlekstrand.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101851
Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
---
FTR I'm not a huge fan of this change, but it's like the least invasive
one.
---
 src/util/Makefile.sources |   1 -
 src/util/u_vector.c       | 110 ----------------------------------------------
 src/util/u_vector.h       |  93 ++++++++++++++++++++++++++++++++++++---
 3 files changed, 88 insertions(+), 116 deletions(-)
 delete mode 100644 src/util/u_vector.c

diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources
index 3315285f05e..08c7a7ea6a8 100644
--- a/src/util/Makefile.sources
+++ b/src/util/Makefile.sources
@@ -51,7 +51,6 @@ MESA_UTIL_FILES := \
 	u_queue.h \
 	u_string.h \
 	u_thread.h \
-	u_vector.c \
 	u_vector.h
 
 MESA_UTIL_GENERATED_FILES = \
diff --git a/src/util/u_vector.c b/src/util/u_vector.c
deleted file mode 100644
index 0de492ccf9a..00000000000
--- a/src/util/u_vector.c
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
- * Copyright © 2015 Intel Corporation
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice (including the next
- * paragraph) shall be included in all copies or substantial portions of the
- * Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- * IN THE SOFTWARE.
- */
-
-#include <string.h>
-#include "util/u_math.h"
-#include "util/u_vector.h"
-
-/** @file u_vector.c
- *
- * A dynamically growable, circular buffer.  Elements are added at head and
- * removed from tail. head and tail are free-running uint32_t indices and we
- * only compute the modulo with size when accessing the array.  This way,
- * number of bytes in the queue is always head - tail, even in case of
- * wraparound.
- */
-
-int
-u_vector_init(struct u_vector *vector, uint32_t element_size, uint32_t size)
-{
-   assert(util_is_power_of_two(size));
-   assert(element_size < size && util_is_power_of_two(element_size));
-
-   vector->head = 0;
-   vector->tail = 0;
-   vector->element_size = element_size;
-   vector->size = size;
-   vector->data = malloc(size);
-
-   return vector->data != NULL;
-}
-
-void *
-u_vector_add(struct u_vector *vector)
-{
-   uint32_t offset, size, split, src_tail, dst_tail;
-   void *data;
-
-   if (vector->head - vector->tail == vector->size) {
-      size = vector->size * 2;
-      data = malloc(size);
-      if (data == NULL)
-         return NULL;
-      src_tail = vector->tail & (vector->size - 1);
-      dst_tail = vector->tail & (size - 1);
-      if (src_tail == 0) {
-         /* Since we know that the vector is full, this means that it's
-          * linear from start to end so we can do one copy.
-          */
-         memcpy((char *)data + dst_tail, vector->data, vector->size);
-      } else {
-         /* In this case, the vector is split into two pieces and we have
-          * to do two copies.  We have to be careful to make sure each
-          * piece goes to the right locations.  Thanks to the change in
-          * size, it may or may not still wrap around.
-          */
-         split = u_align_u32(vector->tail, vector->size);
-         assert(vector->tail <= split && split < vector->head);
-         memcpy((char *)data + dst_tail, (char *)vector->data + src_tail,
-                split - vector->tail);
-         memcpy((char *)data + (split & (size - 1)), vector->data,
-                vector->head - split);
-      }
-      free(vector->data);
-      vector->data = data;
-      vector->size = size;
-   }
-
-   assert(vector->head - vector->tail < vector->size);
-
-   offset = vector->head & (vector->size - 1);
-   vector->head += vector->element_size;
-
-   return (char *)vector->data + offset;
-}
-
-void *
-u_vector_remove(struct u_vector *vector)
-{
-   uint32_t offset;
-
-   if (vector->head == vector->tail)
-      return NULL;
-
-   assert(vector->head - vector->tail <= vector->size);
-
-   offset = vector->tail & (vector->size - 1);
-   vector->tail += vector->element_size;
-
-   return (char *)vector->data + offset;
-}
diff --git a/src/util/u_vector.h b/src/util/u_vector.h
index cd8a95dcbe3..40d52d91207 100644
--- a/src/util/u_vector.h
+++ b/src/util/u_vector.h
@@ -22,15 +22,20 @@
  */
 
 /* 
- * u_vector is a vector based queue for storing arbitrary
- * sized arrays of objects without using a linked list.
+ * A dynamically growable, circular buffer.  Elements are added at head and
+ * removed from tail. head and tail are free-running uint32_t indices and we
+ * only compute the modulo with size when accessing the array.  This way,
+ * number of bytes in the queue is always head - tail, even in case of
+ * wraparound.
  */
 
 #ifndef U_VECTOR_H
 #define U_VECTOR_H
 
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <string.h>
 #include "util/macros.h"
 
 /* TODO - move to u_math.h - name it better etc */
@@ -41,6 +46,13 @@ u_align_u32(uint32_t v, uint32_t a)
    return (v + a - 1) & ~(a - 1);
 }
 
+/* XXX - copies from u_math.h since it requires adding gallium include in 5+ places */
+static inline bool
+u_is_power_of_two(uint32_t v)
+{
+   return (v & (v-1)) == 0;
+}
+
 struct u_vector {
    uint32_t head;
    uint32_t tail;
@@ -49,9 +61,80 @@ struct u_vector {
    void *data;
 };
 
-int u_vector_init(struct u_vector *queue, uint32_t element_size, uint32_t size);
-void *u_vector_add(struct u_vector *queue);
-void *u_vector_remove(struct u_vector *queue);
+MAYBE_UNUSED static int
+u_vector_init(struct u_vector *vector, uint32_t element_size, uint32_t size)
+{
+   assert(u_is_power_of_two(size));
+   assert(element_size < size && u_is_power_of_two(element_size));
+
+   vector->head = 0;
+   vector->tail = 0;
+   vector->element_size = element_size;
+   vector->size = size;
+   vector->data = malloc(size);
+
+   return vector->data != NULL;
+}
+
+MAYBE_UNUSED static void *
+u_vector_add(struct u_vector *vector)
+{
+   uint32_t offset, size, split, src_tail, dst_tail;
+   void *data;
+
+   if (vector->head - vector->tail == vector->size) {
+      size = vector->size * 2;
+      data = malloc(size);
+      if (data == NULL)
+         return NULL;
+      src_tail = vector->tail & (vector->size - 1);
+      dst_tail = vector->tail & (size - 1);
+      if (src_tail == 0) {
+         /* Since we know that the vector is full, this means that it's
+          * linear from start to end so we can do one copy.
+          */
+         memcpy((char *)data + dst_tail, vector->data, vector->size);
+      } else {
+         /* In this case, the vector is split into two pieces and we have
+          * to do two copies.  We have to be careful to make sure each
+          * piece goes to the right locations.  Thanks to the change in
+          * size, it may or may not still wrap around.
+          */
+         split = u_align_u32(vector->tail, vector->size);
+         assert(vector->tail <= split && split < vector->head);
+         memcpy((char *)data + dst_tail, (char *)vector->data + src_tail,
+                split - vector->tail);
+         memcpy((char *)data + (split & (size - 1)), vector->data,
+                vector->head - split);
+      }
+      free(vector->data);
+      vector->data = data;
+      vector->size = size;
+   }
+
+   assert(vector->head - vector->tail < vector->size);
+
+   offset = vector->head & (vector->size - 1);
+   vector->head += vector->element_size;
+
+   return (char *)vector->data + offset;
+}
+
+MAYBE_UNUSED static void *
+u_vector_remove(struct u_vector *vector)
+{
+   uint32_t offset;
+
+   if (vector->head == vector->tail)
+      return NULL;
+
+   assert(vector->head - vector->tail <= vector->size);
+
+   offset = vector->tail & (vector->size - 1);
+   vector->tail += vector->element_size;
+
+   return (char *)vector->data + offset;
+}
 
 static inline int
 u_vector_length(struct u_vector *queue)
-- 
2.13.3



More information about the mesa-dev mailing list