X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=buffer_tree.c;h=962359fbfa253790880f1380551335eaf9861c6d;hp=a7a3220b4d267955ae5fe467d9e08b1c48b6a5f3;hb=11ef83c4abb2ccbdf3f99a8adf98749b2b0656c2;hpb=9facffb38faa01da0d1ba9574f9cc1c47b1deb2e

diff --git a/buffer_tree.c b/buffer_tree.c
index a7a3220b..962359fb 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -8,6 +8,7 @@
 #include "error.h"
 #include "sched.h"
 
+/* whead = NULL means area full */
 struct btr_pool {
 	char *name;
 	char *area_start;
@@ -56,6 +57,17 @@ struct btr_node {
 	void *context;
 };
 
+/**
+ * Create a new buffer pool.
+ *
+ * \param name The name of the new buffer pool.
+ *
+ * \param area The size in bytes of the pool area.
+ *
+ * \return An opaque pointer to the newly created buffer pool. It must be
+ * passed to btr_pool_free() after it is no longer used to deallocate all
+ * resources.
+ */
 struct btr_pool *btr_pool_new(const char *name, size_t area_size)
 {
 	struct btr_pool *btrp;
@@ -70,8 +82,11 @@ struct btr_pool *btr_pool_new(const char *name, size_t area_size)
 	return btrp;
 }
 
-/* whead = NULL means area full */
-
+/**
+ * Dellocate resources used by a buffer pool.
+ *
+ * \param btrp A pointer obtained via btr_pool_new().
+ */
 void btr_pool_free(struct btr_pool *btrp)
 {
 	if (!btrp)
@@ -81,6 +96,14 @@ void btr_pool_free(struct btr_pool *btrp)
 	free(btrp);
 }
 
+/**
+ * Return the size of the buffer pool area.
+ *
+ * \param btrp The buffer pool.
+ *
+ * \return The same value which was passed during creation time to
+ * btr_pool_new().
+ */
 size_t btr_pool_size(struct btr_pool *btrp)
 {
 	return btrp->area_end - btrp->area_start;
@@ -100,6 +123,10 @@ size_t btr_pool_unused(struct btr_pool *btrp)
 	return btr_pool_size(btrp) - btr_pool_filled(btrp);
 }
 
+/*
+ * Return maximal size available for one read. This is
+ * smaller than the value returned by btr_pool_unused().
+ */
 size_t btr_pool_available(struct btr_pool *btrp)
 {
 	if (!btrp->whead)
@@ -122,7 +149,6 @@ void btr_pool_allocate(struct btr_pool *btrp, size_t size)
 
 	if (size == 0)
 		return;
-	//PARA_CRIT_LOG("filled: %zu, alloc %zu\n", btr_pool_filled(btrp), size);
 	assert(size <= btr_pool_available(btrp));
 	end = btrp->whead + size;
 	assert(end <= btrp->area_end);
@@ -132,18 +158,16 @@ void btr_pool_allocate(struct btr_pool *btrp, size_t size)
 		end = btrp->area_start;
 	}
 	if (end == btrp->rhead) {
-		PARA_DEBUG_LOG("btrp buffer full\n");
+		PARA_DEBUG_LOG("%s btrp buffer full\n", btrp->name);
 		end = NULL; /* buffer full */
 	}
 	btrp->whead = end;
-	//PARA_CRIT_LOG("filled: %zu\n", btr_pool_filled(btrp));
 }
 
 static void btr_pool_deallocate(struct btr_pool *btrp, size_t size)
 {
 	char *end = btrp->rhead + size;
 
-	//PARA_CRIT_LOG("filled: %zu, dealloc %zu\n", btr_pool_filled(btrp), size);
 	if (size == 0)
 		return;
 	assert(end <= btrp->area_end);
@@ -155,7 +179,6 @@ static void btr_pool_deallocate(struct btr_pool *btrp, size_t size)
 	btrp->rhead = end;
 	if (btrp->rhead == btrp->whead)
 		btrp->rhead = btrp->whead = btrp->area_start;
-	//PARA_CRIT_LOG("filled: %zu\n", btr_pool_filled(btrp));
 }
 
 #define FOR_EACH_CHILD(_tn, _btrn) list_for_each_entry((_tn), \
@@ -168,25 +191,41 @@ static void btr_pool_deallocate(struct btr_pool *btrp, size_t size)
 #define FOR_EACH_BUFFER_REF_SAFE(_br, _tmp, _btrn) \
 	list_for_each_entry_safe((_br), (_tmp), &(_btrn)->input_queue, node)
 
-struct btr_node *btr_new_node(const char *name, struct btr_node *parent,
-		btr_command_handler handler, void *context)
+struct btr_node *btr_new_node(struct btr_node_description *bnd)
 {
 	struct btr_node *btrn = para_malloc(sizeof(*btrn));
 
-	btrn->name = para_strdup(name);
-	btrn->parent = parent;
-	btrn->execute = handler;
-	btrn->context = context;
+	btrn->name = para_strdup(bnd->name);
+	btrn->parent = bnd->parent;
+	btrn->execute = bnd->handler;
+	btrn->context = bnd->context;
 	btrn->start.tv_sec = 0;
 	btrn->start.tv_usec = 0;
-	if (parent)
-		list_add_tail(&btrn->node, &parent->children);
 	INIT_LIST_HEAD(&btrn->children);
 	INIT_LIST_HEAD(&btrn->input_queue);
-	if (parent)
-		PARA_INFO_LOG("added %s as child of %s\n", name, parent->name);
-	else
-		PARA_INFO_LOG("added %s as btr root\n", name);
+	if (!bnd->child) {
+		if (bnd->parent) {
+			list_add_tail(&btrn->node, &bnd->parent->children);
+			PARA_INFO_LOG("new leaf node: %s (child of %s)\n",
+				bnd->name, bnd->parent->name);
+		} else
+			PARA_INFO_LOG("added %s as btr root\n", bnd->name);
+		goto out;
+	}
+	if (!bnd->parent) {
+		assert(!bnd->child->parent);
+		PARA_INFO_LOG("new root: %s (was %s)\n",
+			bnd->name, bnd->child->name);
+		btrn->parent = NULL;
+		list_add_tail(&bnd->child->node, &btrn->children);
+		/* link it in */
+		bnd->child->parent = btrn;
+		goto out;
+	}
+	PARA_EMERG_LOG("inserting internal nodes not yet supported.\n");
+	exit(EXIT_FAILURE);
+	assert(bnd->child->parent == bnd->parent);
+out:
 	return btrn;
 }
 
@@ -228,7 +267,6 @@ static void btr_drop_buffer_reference(struct btr_buffer_reference *br)
 {
 	struct btr_buffer *btrb = br->btrb;
 
-	//PARA_CRIT_LOG("dropping buffer reference %p\n", br);
 	list_del(&br->node);
 	free(br);
 	btrb->refcount--;
@@ -383,15 +421,8 @@ size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
 		}
 		if (!br->btrb->pool)
 			break;
-		if (result + rv != buf) {
-			PARA_DEBUG_LOG("%s: pool merge impossible: %p != %p\n",
-				btrn->name, result + rv, buf);
+		if (result + rv != buf)
 			break;
-		}
-//		PARA_CRIT_LOG("%s: inplace merge (%zu, %zu)->%zu\n", btrn->name,
-//			rv, sz, rv + sz);
-//		PARA_CRIT_LOG("%s: inplace merge %p (%zu)\n", btrn->name,
-//			result, sz);
 		rv += sz;
 	}
 	if (bufp)
@@ -409,7 +440,6 @@ void btr_consume(struct btr_node *btrn, size_t numbytes)
 	br = get_first_input_br(btrn);
 	assert(br);
 
-	//PARA_CRIT_LOG("wrap count: %zu\n", br->wrap_count);
 	if (br->wrap_count == 0) {
 		/*
 		 * No wrap buffer. Drop buffer references whose buffer
@@ -484,12 +514,17 @@ void btr_remove_node(struct btr_node *btrn)
 size_t btr_get_input_queue_size(struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br;
-	size_t size = 0;
+	size_t size = 0, wrap_consumed = 0;
 
 	FOR_EACH_BUFFER_REF(br, btrn) {
-		//PARA_CRIT_LOG("size: %zu\n", size);
+		if (br->wrap_count != 0) {
+			wrap_consumed = br->consumed;
+			continue;
+		}
 		size += br_available_bytes(br);
 	}
+	assert(wrap_consumed <= size);
+	size -= wrap_consumed;
 	return size;
 }
 
@@ -582,18 +617,20 @@ static bool need_buffer_pool_merge(struct btr_node *btrn)
 
 static void merge_input_pool(struct btr_node *btrn, size_t dest_size)
 {
-	struct btr_buffer_reference *br, *wbr;
+	struct btr_buffer_reference *br, *wbr = NULL;
 	int num_refs; /* including wrap buffer */
-	char *buf, *buf1, *buf2 = NULL;
-	size_t sz, sz1, sz2 = 0, wsz;
+	char *buf, *buf1 = NULL, *buf2 = NULL;
+	size_t sz, sz1 = 0, sz2 = 0, wsz;
 
-	if (list_empty(&btrn->input_queue))
+	br = get_first_input_br(btrn);
+	if (!br || br_available_bytes(br) >= dest_size)
 		return;
-
 	num_refs = 0;
 	FOR_EACH_BUFFER_REF(br, btrn) {
 		num_refs++;
 		sz = btr_get_buffer_by_reference(br, &buf);
+		if (sz == 0)
+			break;
 		if (br->wrap_count != 0) {
 			assert(!wbr);
 			assert(num_refs == 1);
@@ -622,11 +659,16 @@ next:
 		if (sz1 + sz2 >= dest_size)
 			break;
 	}
+	if (!buf2) /* nothing to do */
+		return;
+	assert(buf1 && sz2 > 0);
+	/*
+	 * If the second buffer is large, we only take the first part of it to
+	 * avoid having to memcpy() huge buffers.
+	 */
+	sz2 = PARA_MIN(sz2, (size_t)(64 * 1024));
 	if (!wbr) {
-		assert(buf1);
-		if (!buf2) /* nothing to do */
-			return;
-		/* make a new wrap buffer combining buf1 and buf 2. */
+		/* Make a new wrap buffer combining buf1 and buf2. */
 		sz = sz1 + sz2;
 		buf = para_malloc(sz);
 		PARA_DEBUG_LOG("merging input buffers: (%p:%zu, %p:%zu) -> %p:%zu\n",
@@ -642,6 +684,7 @@ next:
 		para_list_add(&br->node, &btrn->input_queue);
 		return;
 	}
+	PARA_DEBUG_LOG("increasing wrap buffer, sz1: %zu, sz2: %zu\n", sz1, sz2);
 	/*
 	 * We already have a wrap buffer, but it is too small. It might be
 	 * partially used.
@@ -649,10 +692,8 @@ next:
 	wsz = br_available_bytes(wbr);
 	if (wbr->wrap_count == sz1 && wbr->btrb->size >= sz1 + sz2) /* nothing we can do about it */
 		return;
-	assert(buf1 && buf2);
 	sz = sz1 + sz2 - wbr->btrb->size; /* amount of new data */
 	wbr->btrb->size += sz;
-	PARA_DEBUG_LOG("increasing wrap buffer to %zu\n", wbr->btrb->size);
 	wbr->btrb->buf = para_realloc(wbr->btrb->buf, wbr->btrb->size);
 	/* copy the new data to the end of the reallocated buffer */
 	assert(sz2 >= sz);
@@ -745,6 +786,25 @@ void btr_log_tree(struct btr_node *btrn, int loglevel)
 	return log_tree_recursively(btrn, loglevel, 0);
 }
 
+/*
+ * \return \a root if \a name is \p NULL.
+ */
+struct btr_node *btr_search_node(const char *name, struct btr_node *root)
+{
+	struct btr_node *ch;
+
+	if (!name)
+		return root;
+	if (!strcmp(root->name, name))
+		return root;
+	FOR_EACH_CHILD(ch, root) {
+		struct btr_node *result = btr_search_node(name, ch);
+		if (result)
+			return result;
+	}
+	return NULL;
+}
+
 /** 640K ought to be enough for everybody ;) */
 #define BTRN_MAX_PENDING (640 * 1024)
 
@@ -753,8 +813,7 @@ int btr_node_status(struct btr_node *btrn, size_t min_iqs,
 {
 	size_t iqs;
 
-	if (!btrn)
-		return 0;
+	assert(btrn);
 	if (type != BTR_NT_LEAF) {
 		if (btr_no_children(btrn))
 			return -E_BTR_NO_CHILD;