The branch, v3-2-test has been updated
       via  f98c68a8a4882cb0a1b7e8985f3eba5ebb8287e3 (commit)
       via  d27e6c0548d21394f6399d3b737d175ffed8420d (commit)
       via  287e29d988813007eeebc0c2bef3b46ab8bedee9 (commit)
      from  778199cf00196f81fd96deae1370d8cbc438c5bf (commit)

http://gitweb.samba.org/?p=samba.git;a=shortlog;h=v3-2-test


- Log -----------------------------------------------------------------
commit f98c68a8a4882cb0a1b7e8985f3eba5ebb8287e3
Merge: d27e6c0548d21394f6399d3b737d175ffed8420d 
778199cf00196f81fd96deae1370d8cbc438c5bf
Author: Jeremy Allison <[EMAIL PROTECTED]>
Date:   Wed Jan 9 17:08:20 2008 -0800

    Merge branch 'v3-2-test' of ssh://[EMAIL PROTECTED]/data/git/samba into 
v3-2-test

commit d27e6c0548d21394f6399d3b737d175ffed8420d
Author: Jeremy Allison <[EMAIL PROTECTED]>
Date:   Wed Jan 9 17:07:58 2008 -0800

    Add the calls to make use of talloc_pools in a talloc_stackframe.
    Jeremy.

commit 287e29d988813007eeebc0c2bef3b46ab8bedee9
Author: Volker Lendecke <[EMAIL PROTECTED]>
Date:   Sat Jan 5 18:26:54 2008 +0100

    Implement talloc_pool()
    
    A talloc pool is a chunk of memory that can be used as a context for further
    talloc calls. Allocations with the pool as the parent just chew from that
    memory by incrementing a pointer. If the talloc pool is full, then we fall 
back
    to the normal system-level malloc(3) to get memory.
    
    The use case for talloc pools is the transient memory that is used for 
handling
    a single SMB request. Incrementing a pointer will be way faster than any 
malloc
    implementation.
    
    There is a downside of this: If you use talloc_steal() to move something 
out of
    the pool, the whole pool memory is kept around until the last object inside 
the
    pool is freed. So if you talloc_free() the pool, it might happen that the
    memory is freed later. So don't hang anything off a talloc pool that should
    live long.
    
    Volker

-----------------------------------------------------------------------

Summary of changes:
 source/include/talloc_stack.h |    1 +
 source/lib/talloc/talloc.c    |  176 +++++++++++++++++++++++++++++++++++++++--
 source/lib/talloc/talloc.h    |    1 +
 source/lib/talloc/testsuite.c |   37 +++++++++
 source/lib/talloc_stack.c     |   18 ++++-
 5 files changed, 224 insertions(+), 9 deletions(-)


Changeset truncated at 500 lines:

diff --git a/source/include/talloc_stack.h b/source/include/talloc_stack.h
index 331893c..a2a12f8 100644
--- a/source/include/talloc_stack.h
+++ b/source/include/talloc_stack.h
@@ -45,6 +45,7 @@
  */
 
 TALLOC_CTX *talloc_stackframe(void);
+TALLOC_CTX *talloc_stackframe_pool(size_t poolsize);
 
 /*
  * Get us the current top of the talloc stack.
diff --git a/source/lib/talloc/talloc.c b/source/lib/talloc/talloc.c
index 3e976bc..178bbb9 100644
--- a/source/lib/talloc/talloc.c
+++ b/source/lib/talloc/talloc.c
@@ -60,6 +60,8 @@
 #define TALLOC_MAGIC 0xe814ec70
 #define TALLOC_FLAG_FREE 0x01
 #define TALLOC_FLAG_LOOP 0x02
+#define TALLOC_FLAG_POOL 0x04          /* This is a talloc pool */
+#define TALLOC_FLAG_POOLMEM 0x08       /* This is allocated in a pool */
 #define TALLOC_MAGIC_REFERENCE ((const char *)1)
 
 /* by default we abort when given a bad pointer (such as when talloc_free() is 
called 
@@ -109,6 +111,19 @@ struct talloc_chunk {
        const char *name;
        size_t size;
        unsigned flags;
+
+       /*
+        * "pool" has dual use:
+        *
+        * For the talloc pool itself (i.e. TALLOC_FLAG_POOL is set), "pool"
+        * marks the end of the currently allocated area.
+        *
+        * For members of the pool (i.e. TALLOC_FLAG_POOLMEM is set), "pool"
+        * is a pointer to the struct talloc_chunk of the pool that it was
+        * allocated from. This way children can quickly find the pool to chew
+        * from.
+        */
+       void *pool;
 };
 
 /* 16 byte alignment seems to keep everyone happy */
@@ -200,12 +215,82 @@ const char *talloc_parent_name(const void *ptr)
        return tc? tc->name : NULL;
 }
 
+/*
+  A pool carries an in-pool object count count in the first 16 bytes.
+  bytes. This is done to support talloc_steal() to a parent outside of the
+  pool. The count includes the pool itself, so a talloc_free() on a pool will
+  only destroy the pool if the count has dropped to zero. A talloc_free() of a
+  pool member will reduce the count, and eventually also call free(3) on the
+  pool memory.
+
+  The object count is not put into "struct talloc_chunk" because it is only
+  relevant for talloc pools and the alignment to 16 bytes would increase the
+  memory footprint of each talloc chunk by those 16 bytes.
+*/
+
+#define TALLOC_POOL_HDR_SIZE 16
+
+static unsigned int *talloc_pool_objectcount(struct talloc_chunk *tc)
+{
+       return (unsigned int *)((char *)tc + sizeof(struct talloc_chunk));
+}
+
+/*
+  Allocate from a pool
+*/
+
+static struct talloc_chunk *talloc_alloc_pool(struct talloc_chunk *parent,
+                                             size_t size)
+{
+       struct talloc_chunk *pool_ctx = NULL;
+       size_t space_left;
+       struct talloc_chunk *result;
+
+       if (parent == NULL) {
+               return NULL;
+       }
+
+       if (parent->flags & TALLOC_FLAG_POOL) {
+               pool_ctx = parent;
+       }
+       else if (parent->flags & TALLOC_FLAG_POOLMEM) {
+               pool_ctx = (struct talloc_chunk *)parent->pool;
+       }
+
+       if (pool_ctx == NULL) {
+               return NULL;
+       }
+
+       space_left = ((char *)pool_ctx + TC_HDR_SIZE + pool_ctx->size)
+               - ((char *)pool_ctx->pool);
+
+       /*
+        * Align size to 16 bytes
+        */
+       size = ((size + 15) & ~15);
+
+       if (space_left < size) {
+               return NULL;
+       }
+
+       result = (struct talloc_chunk *)pool_ctx->pool;
+
+       pool_ctx->pool = (void *)((char *)result + size);
+
+       result->flags = TALLOC_MAGIC | TALLOC_FLAG_POOLMEM;
+       result->pool = pool_ctx;
+
+       *talloc_pool_objectcount(pool_ctx) += 1;
+
+       return result;
+}
+
 /* 
    Allocate a bit of memory as a child of an existing pointer
 */
 static inline void *__talloc(const void *context, size_t size)
 {
-       struct talloc_chunk *tc;
+       struct talloc_chunk *tc = NULL;
 
        if (unlikely(context == NULL)) {
                context = null_context;
@@ -215,11 +300,19 @@ static inline void *__talloc(const void *context, size_t 
size)
                return NULL;
        }
 
-       tc = (struct talloc_chunk *)malloc(TC_HDR_SIZE+size);
-       if (unlikely(tc == NULL)) return NULL;
+       if (context != NULL) {
+               tc = talloc_alloc_pool(talloc_chunk_from_ptr(context),
+                                      TC_HDR_SIZE+size);
+       }
+
+       if (tc == NULL) {
+               tc = (struct talloc_chunk *)malloc(TC_HDR_SIZE+size);
+               if (unlikely(tc == NULL)) return NULL;
+               tc->flags = TALLOC_MAGIC;
+               tc->pool  = NULL;
+       }
 
        tc->size = size;
-       tc->flags = TALLOC_MAGIC;
        tc->destructor = NULL;
        tc->child = NULL;
        tc->name = NULL;
@@ -246,6 +339,29 @@ static inline void *__talloc(const void *context, size_t 
size)
 }
 
 /*
+ * Create a talloc pool
+ */
+
+void *talloc_pool(const void *context, size_t size)
+{
+       void *result = __talloc(context, size + TALLOC_POOL_HDR_SIZE);
+       struct talloc_chunk *tc;
+
+       if (unlikely(result == NULL)) {
+               return NULL;
+       }
+
+       tc = talloc_chunk_from_ptr(result);
+
+       tc->flags |= TALLOC_FLAG_POOL;
+       tc->pool = (char *)result + TALLOC_POOL_HDR_SIZE;
+
+       *talloc_pool_objectcount(tc) = 1;
+
+       return result;
+}
+
+/*
   setup a destructor to be called on free of a pointer
   the destructor should return 0 on success, or -1 on failure.
   if the destructor fails then the free is failed, and the memory can
@@ -420,7 +536,29 @@ static inline int _talloc_free(void *ptr)
        }
 
        tc->flags |= TALLOC_FLAG_FREE;
-       free(tc);
+
+       if (tc->flags & (TALLOC_FLAG_POOL|TALLOC_FLAG_POOLMEM)) {
+               struct talloc_chunk *pool;
+               unsigned int *pool_object_count;
+
+               pool = (tc->flags & TALLOC_FLAG_POOL)
+                       ? tc : (struct talloc_chunk *)tc->pool;
+
+               pool_object_count = talloc_pool_objectcount(pool);
+
+               if (*pool_object_count == 0) {
+                       TALLOC_ABORT("Pool object count zero!");
+               }
+
+               *pool_object_count -= 1;
+
+               if (*pool_object_count == 0) {
+                       free(pool);
+               }
+       }
+       else {
+               free(tc);
+       }
        return 0;
 }
 
@@ -718,6 +856,10 @@ void talloc_free_children(void *ptr)
                        talloc_steal(new_parent, child);
                }
        }
+
+       if (tc->flags & TALLOC_FLAG_POOL) {
+               tc->pool = ((char *)tc + TC_HDR_SIZE + TALLOC_POOL_HDR_SIZE);
+       }
 }
 
 /* 
@@ -769,6 +911,7 @@ void *_talloc_realloc(const void *context, void *ptr, 
size_t size, const char *n
 {
        struct talloc_chunk *tc;
        void *new_ptr;
+       bool malloced = false;
 
        /* size zero is equivalent to free() */
        if (unlikely(size == 0)) {
@@ -808,7 +951,23 @@ void *_talloc_realloc(const void *context, void *ptr, 
size_t size, const char *n
                free(tc);
        }
 #else
-       new_ptr = realloc(tc, size + TC_HDR_SIZE);
+       if (tc->flags & TALLOC_FLAG_POOLMEM) {
+
+               new_ptr = talloc_alloc_pool(tc, size + TC_HDR_SIZE);
+               *talloc_pool_objectcount(tc->pool) -= 1;
+
+               if (new_ptr == NULL) {
+                       new_ptr = malloc(TC_HDR_SIZE+size);
+                       malloced = true;
+               }
+
+               if (new_ptr) {
+                       memcpy(new_ptr, tc, MIN(tc->size,size) + TC_HDR_SIZE);
+               }
+       }
+       else {
+               new_ptr = realloc(tc, size + TC_HDR_SIZE);
+       }
 #endif
        if (unlikely(!new_ptr)) {       
                tc->flags &= ~TALLOC_FLAG_FREE; 
@@ -816,7 +975,10 @@ void *_talloc_realloc(const void *context, void *ptr, 
size_t size, const char *n
        }
 
        tc = (struct talloc_chunk *)new_ptr;
-       tc->flags &= ~TALLOC_FLAG_FREE; 
+       tc->flags &= ~TALLOC_FLAG_FREE;
+       if (malloced) {
+               tc->flags &= ~TALLOC_FLAG_POOLMEM;
+       }
        if (tc->parent) {
                tc->parent->child = tc;
        }
diff --git a/source/lib/talloc/talloc.h b/source/lib/talloc/talloc.h
index e103391..5431971 100644
--- a/source/lib/talloc/talloc.h
+++ b/source/lib/talloc/talloc.h
@@ -116,6 +116,7 @@ typedef void TALLOC_CTX;
 
 /* The following definitions come from talloc.c  */
 void *_talloc(const void *context, size_t size);
+void *talloc_pool(const void *context, size_t size);
 void _talloc_set_destructor(const void *ptr, int (*destructor)(void *));
 int talloc_increase_ref_count(const void *ptr);
 size_t talloc_reference_count(const void *ptr);
diff --git a/source/lib/talloc/testsuite.c b/source/lib/talloc/testsuite.c
index e16c91f..fedbda9 100644
--- a/source/lib/talloc/testsuite.c
+++ b/source/lib/talloc/testsuite.c
@@ -813,6 +813,25 @@ static bool test_speed(void)
 
        talloc_free(ctx);
 
+       ctx = talloc_pool(NULL, 1024);
+
+       tv = timeval_current();
+       count = 0;
+       do {
+               void *p1, *p2, *p3;
+               for (i=0;i<loop;i++) {
+                       p1 = talloc_size(ctx, loop % 100);
+                       p2 = talloc_strdup(p1, "foo bar");
+                       p3 = talloc_size(p1, 300);
+                       talloc_free_children(ctx);
+               }
+               count += 3 * loop;
+       } while (timeval_elapsed(&tv) < 5.0);
+
+       talloc_free(ctx);
+
+       fprintf(stderr, "talloc_pool: %.0f ops/sec\n", 
count/timeval_elapsed(&tv));
+
        tv = timeval_current();
        count = 0;
        do {
@@ -1066,6 +1085,23 @@ static bool test_autofree(void)
        return true;
 }
 
+static bool test_pool(void)
+{
+       void *pool;
+       void *p1, *p2, *p3, *p4;
+
+       pool = talloc_pool(NULL, 1024);
+
+       p1 = talloc_size(pool, 80);
+       p2 = talloc_size(pool, 20);
+       p3 = talloc_size(p1, 50);
+       p4 = talloc_size(p3, 1000);
+
+       talloc_free(pool);
+
+       return true;
+}
+
 struct torture_context;
 bool torture_local_talloc(struct torture_context *tctx)
 {
@@ -1094,6 +1130,7 @@ bool torture_local_talloc(struct torture_context *tctx)
        ret &= test_free_parent_deny_child(); 
        ret &= test_talloc_ptrtype();
        ret &= test_talloc_free_in_destructor();
+       ret &= test_pool();
 
        if (ret) {
                ret &= test_speed();
diff --git a/source/lib/talloc_stack.c b/source/lib/talloc_stack.c
index d887b2d..08ef228 100644
--- a/source/lib/talloc_stack.c
+++ b/source/lib/talloc_stack.c
@@ -64,7 +64,7 @@ static int talloc_pop(TALLOC_CTX *frame)
  * not explicitly freed.
  */
 
-TALLOC_CTX *talloc_stackframe(void)
+static TALLOC_CTX *talloc_stackframe_internal(size_t poolsize)
 {
        TALLOC_CTX **tmp, *top;
 
@@ -78,7 +78,11 @@ TALLOC_CTX *talloc_stackframe(void)
                talloc_stack_arraysize = talloc_stacksize + 1;
         }
 
-       top = talloc_new(talloc_stack);
+       if (poolsize) {
+               top = talloc_pool(talloc_stack, poolsize);
+       } else {
+               top = talloc_new(talloc_stack);
+       }
 
        if (top == NULL) {
                goto fail;
@@ -94,6 +98,16 @@ TALLOC_CTX *talloc_stackframe(void)
        return NULL;
 }
 
+TALLOC_CTX *talloc_stackframe(void)
+{
+       return talloc_stackframe_internal(0);
+}
+
+TALLOC_CTX *talloc_stackframe_pool(size_t poolsize)
+{
+       return talloc_stackframe_internal(poolsize);
+}
+
 /*
  * Get us the current top of the talloc stack.
  */


-- 
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