r15890@tombo: nickm | 2008-01-12 17:19:51 -0500

 Add a --disable-buffer-freelists configure argument to build without buffer RAM chunk freelists, so we can benchmark the impact of this.


svn:r13121

configure.in

@@ -34,13 +34,20 @@ AC_ARG_ENABLE(iphone,
    CFLAGS="$CFLAGS -D__DARWIN_UNIX03 -DIPHONE"
   fi])
 
+#XXXX020 We should make these enabled or not, before 0.2.0.x-final
 AC_ARG_ENABLE(cell-pool,
      AS_HELP_STRING(--disable-cell-pool, disable pool allocator for cells))
+AC_ARG_ENABLE(buf-freelists,
+   AS_HELP_STRING(--disable-buf-freelists, disable freelists for buffer RAM))
 
 if test x$enable_cell_pool != xno; then
   AC_DEFINE(ENABLE_CELL_POOL, 1,
             [Defined if we try to use the pool allocator for queued cells])
 fi
+if test x$enable_buf_freelists != xno; then
+  AC_DEFINE(ENABLE_BUF_FREELISTS, 1,
+            [Defined if we try to use freelists for buffer RAM chunks])
+fi
 
 AC_ARG_ENABLE(transparent,
      AS_HELP_STRING(--disable-transparent, disable transparent proxy support),

src/or/buffers.c

@@ -95,6 +95,7 @@ chunk_repack(chunk_t *chunk)
   chunk->data = &chunk->mem[0];
 }
 
+#ifdef ENABLE_BUF_FREELISTS
 /** A freelist of chunks. */
 typedef struct chunk_freelist_t {
   size_t alloc_size; /**< What size chunks does this freelist hold? */
@@ -188,6 +189,24 @@ chunk_new_with_alloc_size(size_t alloc)
   ch->data = &ch->mem[0];
   return ch;
 }
+#else
+static void
+chunk_free(chunk_t *chunk)
+{
+  tor_free(chunk);
+}
+static INLINE chunk_t *
+chunk_new_with_alloc_size(size_t alloc)
+{
+  chunk_t *ch;
+  ch = tor_malloc_roundup(&alloc);
+  ch->next = NULL;
+  ch->datalen = 0;
+  ch->memlen = CHUNK_SIZE_WITH_ALLOC(alloc);
+  ch->data = &ch->mem[0];
+  return ch;
+}
+#endif
 
 /** Allocate a new chunk with memory size of <b>sz</b>. */
 #define chunk_new_with_capacity(sz) \
@@ -221,6 +240,7 @@ static INLINE size_t
 preferred_chunk_size(size_t target)
 {
   /* XXXX020 use log2 code, maybe. */
+  /* XXXX020 or make sizing code more fine-grained! */
   size_t sz = MIN_CHUNK_ALLOC;
   while (CHUNK_SIZE_WITH_ALLOC(sz) < target) {
     sz <<= 1;
@@ -233,6 +253,7 @@ preferred_chunk_size(size_t target)
 void
 buf_shrink_freelists(int free_all)
 {
+#ifdef ENABLE_BUF_FREELISTS
   int i;
   for (i = 0; freelists[i].alloc_size; ++i) {
     int slack = freelists[i].slack;
@@ -267,6 +288,9 @@ buf_shrink_freelists(int free_all)
     freelists[i].lowest_length = freelists[i].cur_length;
     assert_freelist_ok(&freelists[i]);
   }
+#else
+  (void) free_all;
+#endif
 }
 
 /** Describe the current status of the freelists at log level <b>severity</b>.
@@ -274,6 +298,7 @@ buf_shrink_freelists(int free_all)
 void
 buf_dump_freelist_sizes(int severity)
 {
+#ifdef ENABLE_BUF_FREELISTS
   int i;
   log(severity, LD_MM, "====== Buffer freelists:");
   for (i = 0; freelists[i].alloc_size; ++i) {
@@ -290,6 +315,9 @@ buf_dump_freelist_sizes(int severity)
   }
   log(severity, LD_MM, U64_FORMAT" allocations in non-freelist sizes",
       U64_PRINTF_ARG(n_freelist_miss));
+#else
+  (void)severity;
+#endif
 }
 
 /** Magic value for buf_t.magic, to catch pointer errors. */
@@ -1612,6 +1640,7 @@ assert_buf_ok(buf_t *buf)
   }
 }
 
+#ifdef ENABLE_BUF_FREELISTS
 /** Log an error and exit if <b>fl</b> is corrupted.
  */
 static void
@@ -1629,4 +1658,5 @@ assert_freelist_ok(chunk_freelist_t *fl)
   tor_assert(n >= fl->lowest_length);
   tor_assert(n <= fl->max_length);
 }
+#endif