#include "string.h"
#include "buffer_tree.h"
#include "error.h"
+#include "sched.h"
+/* whead = NULL means area full */
+struct btr_pool {
+ char *name;
+ char *area_start;
+ char *area_end;
+ char *rhead;
+ char *whead;
+};
+
+enum btr_buffer_flags {
+ /* changes the way the buffer is deallocated */
+ BTR_BF_BTR_POOL = 1,
+};
struct btr_buffer {
char *buf;
size_t size;
/** The number of references to this buffer. */
int refcount;
+ struct btr_pool *pool;
};
struct btr_buffer_reference {
size_t consumed;
/* Each buffer reference belongs to the buffer queue list of some buffer tree node. */
struct list_head node;
+ size_t wrap_count;
};
struct btr_node {
struct list_head node;
/* The children nodes of this btr node are linked together in a list. */
struct list_head children;
+ /* Time of first data transfer. */
+ struct timeval start;
/**
* The input queue is a list of references to btr buffers. Each item on
* the list represents an input buffer which has not been completely
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;
+
+ PARA_INFO_LOG("%s, %zu bytes\n", name, area_size);
+ btrp = para_malloc(sizeof(*btrp));
+ btrp->area_start = para_malloc(area_size);
+ btrp->area_end = btrp->area_start + area_size;
+ btrp->rhead = btrp->area_start;
+ btrp->whead = btrp->area_start;
+ btrp->name = para_strdup(name);
+ return btrp;
+}
+
+/**
+ * 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)
+ return;
+ free(btrp->area_start);
+ free(btrp->name);
+ 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;
+}
+
+size_t btr_pool_filled(struct btr_pool *btrp)
+{
+ if (!btrp->whead)
+ return btr_pool_size(btrp);
+ if (btrp->rhead <= btrp->whead)
+ return btrp->whead - btrp->rhead;
+ return btr_pool_size(btrp) - (btrp->rhead - btrp->whead);
+}
+
+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)
+ return 0;
+ if (btrp->rhead <= btrp->whead)
+ return btrp->area_end - btrp->whead;
+ return btrp->rhead - btrp->whead;
+}
+
+size_t btr_pool_get_buffer(struct btr_pool *btrp, char **result)
+{
+ if (result)
+ *result = btrp->whead;
+ return btr_pool_available(btrp);
+}
+
+void btr_pool_allocate(struct btr_pool *btrp, size_t size)
+{
+ char *end;
+
+ if (size == 0)
+ return;
+ assert(size <= btr_pool_available(btrp));
+ end = btrp->whead + size;
+ assert(end <= btrp->area_end);
+
+ if (end == btrp->area_end) {
+ PARA_DEBUG_LOG("%s: end of pool area reached\n", btrp->name);
+ end = btrp->area_start;
+ }
+ if (end == btrp->rhead) {
+ PARA_DEBUG_LOG("%s btrp buffer full\n", btrp->name);
+ end = NULL; /* buffer full */
+ }
+ btrp->whead = end;
+}
+
+static void btr_pool_deallocate(struct btr_pool *btrp, size_t size)
+{
+ char *end = btrp->rhead + size;
+
+ if (size == 0)
+ return;
+ assert(end <= btrp->area_end);
+ assert(size <= btr_pool_filled(btrp));
+ if (end == btrp->area_end)
+ end = btrp->area_start;
+ if (!btrp->whead)
+ btrp->whead = btrp->rhead;
+ btrp->rhead = end;
+ if (btrp->rhead == btrp->whead)
+ btrp->rhead = btrp->whead = btrp->area_start;
+}
+
#define FOR_EACH_CHILD(_tn, _btrn) list_for_each_entry((_tn), \
&((_btrn)->children), node)
#define FOR_EACH_CHILD_SAFE(_tn, _tmp, _btrn) \
#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;
- if (parent)
- list_add_tail(&btrn->node, &parent->children);
+ 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;
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;
}
/*
* Allocate a new btr buffer.
*
- * The freshly allocated buffer will have a zero refcount.
+ * The freshly allocated buffer will have a zero refcount and will
+ * not be associated with a btr pool.
*/
static struct btr_buffer *new_btrb(char *buf, size_t size)
{
- struct btr_buffer *btrb = para_malloc(sizeof(*btrb));
+ struct btr_buffer *btrb = para_calloc(sizeof(*btrb));
btrb->buf = buf;
btrb->size = size;
- btrb->refcount = 0;
return btrb;
}
+static void dealloc_buffer(struct btr_buffer *btrb)
+{
+ if (btrb->pool)
+ btr_pool_deallocate(btrb->pool, btrb->size);
+ else
+ free(btrb->buf);
+}
+
+static struct btr_buffer_reference *get_first_input_br(struct btr_node *btrn)
+{
+ if (list_empty(&btrn->input_queue))
+ return NULL;
+ return list_first_entry(&btrn->input_queue,
+ struct btr_buffer_reference, node);
+}
+
/*
* Deallocate the reference, release the resources if refcount drops to zero.
*/
{
struct btr_buffer *btrb = br->btrb;
- //PARA_CRIT_LOG("dropping buffer reference %p\n", br);
list_del(&br->node);
free(br);
btrb->refcount--;
if (btrb->refcount == 0) {
- free(btrb->buf);
+ dealloc_buffer(btrb);
free(btrb);
}
}
{
struct btr_node *ch;
+ if (btrn->start.tv_sec == 0)
+ btrn->start = *now;
FOR_EACH_CHILD(ch, btrn) {
- struct btr_buffer_reference *br = para_malloc(sizeof(*br));
+ struct btr_buffer_reference *br = para_calloc(sizeof(*br));
br->btrb = btrb;
br->consumed = consumed;
list_add_tail(&br->node, &ch->input_queue);
btrb->refcount++;
+ if (ch->start.tv_sec == 0)
+ ch->start = *now;
}
}
{
struct btr_buffer *btrb;
+ assert(size != 0);
+ if (list_empty(&btrn->children)) {
+ free(buf);
+ return;
+ }
+ btrb = new_btrb(buf, size);
+ add_btrb_to_children(btrb, btrn, 0);
+}
+
+void btr_add_output_pool(struct btr_pool *btrp, size_t size,
+ struct btr_node *btrn)
+{
+ struct btr_buffer *btrb;
+ char *buf;
+ size_t avail;
+
+ assert(size != 0);
+ if (list_empty(&btrn->children))
+ return;
+ avail = btr_pool_get_buffer(btrp, &buf);
+ assert(avail >= size);
+ btr_pool_allocate(btrp, size);
btrb = new_btrb(buf, size);
+ btrb->pool = btrp;
add_btrb_to_children(btrb, btrn, 0);
}
+void btr_copy(const void *src, size_t n, struct btr_pool *btrp,
+ struct btr_node *btrn)
+{
+ char *buf;
+ size_t sz, copy;
+
+ if (n == 0)
+ return;
+ assert(n <= btr_pool_unused(btrp));
+ sz = btr_pool_get_buffer(btrp, &buf);
+ copy = PARA_MIN(sz, n);
+ memcpy(buf, src, copy);
+ btr_add_output_pool(btrp, copy, btrn);
+ if (copy == n)
+ return;
+ sz = btr_pool_get_buffer(btrp, &buf);
+ assert(sz >= n - copy);
+ memcpy(buf, src + copy, n - copy);
+ btr_add_output_pool(btrp, n - copy, btrn);
+}
+
static void btr_pushdown_br(struct btr_buffer_reference *br, struct btr_node *btrn)
{
add_btrb_to_children(br->btrb, btrn, br->consumed);
btr_pushdown_br(br, btrn);
}
+int btr_pushdown_one(struct btr_node *btrn)
+{
+ struct btr_buffer_reference *br;
+
+ if (list_empty(&btrn->input_queue))
+ return 0;
+ br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
+ btr_pushdown_br(br, btrn);
+ return 1;
+}
+
/* Return true if this node has no children. */
bool btr_no_children(struct btr_node *btrn)
{
size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char **buf)
{
- *buf = br->btrb->buf + br->consumed;
+ if (buf)
+ *buf = br->btrb->buf + br->consumed;
return br_available_bytes(br);
}
+/**
+ * \return zero if the input buffer queue is empty.
+ */
size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
{
struct btr_buffer_reference *br;
+ char *buf, *result = NULL;
+ size_t sz, rv = 0;
- if (list_empty(&btrn->input_queue)) {
- *bufp = NULL;
- return 0;
+ FOR_EACH_BUFFER_REF(br, btrn) {
+ sz = btr_get_buffer_by_reference(br, &buf);
+ if (!result) {
+ result = buf;
+ rv = sz;
+ if (!br->btrb->pool)
+ break;
+ continue;
+ }
+ if (!br->btrb->pool)
+ break;
+ if (result + rv != buf)
+ break;
+ rv += sz;
}
- br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
- return btr_get_buffer_by_reference(br, bufp);
+ if (bufp)
+ *bufp = result;
+ return rv;
}
void btr_consume(struct btr_node *btrn, size_t numbytes)
{
- struct btr_buffer_reference *br;
+ struct btr_buffer_reference *br, *tmp;
+ size_t sz;
- assert(!list_empty(&btrn->input_queue));
- br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
- assert(br->consumed + numbytes <= br->btrb->size);
- br->consumed += numbytes;
- if (br->consumed == br->btrb->size)
- btr_drop_buffer_reference(br);
+ if (numbytes == 0)
+ return;
+ br = get_first_input_br(btrn);
+ assert(br);
+
+ if (br->wrap_count == 0) {
+ /*
+ * No wrap buffer. Drop buffer references whose buffer
+ * has been fully used. */
+ FOR_EACH_BUFFER_REF_SAFE(br, tmp, btrn) {
+ if (br->consumed + numbytes <= br->btrb->size) {
+ br->consumed += numbytes;
+ if (br->consumed == br->btrb->size)
+ btr_drop_buffer_reference(br);
+ return;
+ }
+ numbytes -= br->btrb->size - br->consumed;
+ btr_drop_buffer_reference(br);
+ }
+ assert(true);
+ }
+ /*
+
+ We have a wrap buffer, consume from it. If in total,
+ i.e. including previous calls to brt_consume(), less than
+ wrap_count has been consumed, there's nothing more we can do.
+
+ Otherwise we drop the wrap buffer and consume from subsequent
+ buffers of the input queue the correct amount of bytes. This
+ is the total number of bytes that have been consumed from the
+ wrap buffer.
+*/
+ PARA_DEBUG_LOG("consuming %zu/%zu bytes from wrap buffer\n", numbytes,
+ br_available_bytes(br));
+
+ assert(numbytes <= br_available_bytes(br));
+ if (br->consumed + numbytes < br->wrap_count) {
+ br->consumed += numbytes;
+ return;
+ }
+ PARA_DEBUG_LOG("dropping wrap buffer (%zu bytes)\n", br->btrb->size);
+ /* get rid of the wrap buffer */
+ sz = br->consumed + numbytes;
+ btr_drop_buffer_reference(br);
+ return btr_consume(btrn, sz);
}
static void flush_input_queue(struct btr_node *btrn)
btr_drop_buffer_reference(br);
}
-void btr_del_node(struct btr_node *btrn)
+void btr_free_node(struct btr_node *btrn)
+{
+ if (!btrn)
+ return;
+ free(btrn->name);
+ free(btrn);
+}
+
+void btr_remove_node(struct btr_node *btrn)
{
struct btr_node *ch;
if (!btrn)
return;
- PARA_NOTICE_LOG("deleting %s\n", btrn->name);
+ PARA_NOTICE_LOG("removing btr node %s from buffer tree\n", btrn->name);
FOR_EACH_CHILD(ch, btrn)
ch->parent = NULL;
flush_input_queue(btrn);
if (btrn->parent)
list_del(&btrn->node);
- free(btrn->name);
- free(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;
}
-int btr_splice_out_node(struct btr_node *btrn)
+void btr_splice_out_node(struct btr_node *btrn)
{
struct btr_node *ch, *tmp;
- if (!btrn)
- return -ERRNO_TO_PARA_ERROR(EINVAL);
- if (btr_get_input_queue_size(btrn) != 0)
- return -ERRNO_TO_PARA_ERROR(EINVAL);
+ assert(btrn);
PARA_NOTICE_LOG("splicing out %s\n", btrn->name);
+ btr_pushdown(btrn);
if (btrn->parent)
list_del(&btrn->node);
FOR_EACH_CHILD_SAFE(ch, tmp, btrn) {
list_move(&ch->node, &btrn->parent->children);
}
assert(list_empty(&btrn->children));
- free(btrn->name);
- free(btrn);
- return 1;
}
/**
return btrn->context;
}
+static bool need_buffer_pool_merge(struct btr_node *btrn)
+{
+ struct btr_buffer_reference *br = get_first_input_br(btrn);
+
+ if (!br)
+ return false;
+ if (br->wrap_count != 0)
+ return true;
+ if (br->btrb->pool)
+ return true;
+ return false;
+}
+
+static void merge_input_pool(struct btr_node *btrn, size_t dest_size)
+{
+ struct btr_buffer_reference *br, *wbr = NULL;
+ int num_refs; /* including wrap buffer */
+ char *buf, *buf1 = NULL, *buf2 = NULL;
+ size_t sz, sz1 = 0, sz2 = 0, wsz;
+
+ 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);
+ wbr = br;
+ if (sz >= dest_size)
+ return;
+ continue;
+ }
+ if (!buf1) {
+ buf1 = buf;
+ sz1 = sz;
+ goto next;
+ }
+ if (buf1 + sz1 == buf) {
+ sz1 += sz;
+ goto next;
+ }
+ if (!buf2) {
+ buf2 = buf;
+ sz2 = sz;
+ goto next;
+ }
+ assert(buf2 + sz2 == buf);
+ sz2 += sz;
+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) {
+ /* 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",
+ buf1, sz1, buf2, sz2, buf, sz);
+ memcpy(buf, buf1, sz1);
+ memcpy(buf + sz1, buf2, sz2);
+ br = para_calloc(sizeof(*br));
+ br->btrb = new_btrb(buf, sz);
+ br->btrb->refcount = 1;
+ br->consumed = 0;
+ /* This is a wrap buffer */
+ br->wrap_count = sz1;
+ 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.
+ */
+ wsz = br_available_bytes(wbr);
+ if (wbr->wrap_count == sz1 && wbr->btrb->size >= sz1 + sz2) /* nothing we can do about it */
+ return;
+ sz = sz1 + sz2 - wbr->btrb->size; /* amount of new data */
+ wbr->btrb->size += sz;
+ 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);
+ memcpy(wbr->btrb->buf + wbr->btrb->size - sz, buf2 + sz2 - sz, sz);
+}
+
/**
* Merge the first two input buffers into one.
*
* This is a quite expensive operation.
*
- * \return The number of buffers that have been merged (zero, one or two).
+ * \return The number of buffers that have been available (zero, one or two).
*/
-int btr_merge(struct btr_node *btrn)
+static int merge_input(struct btr_node *btrn)
{
struct btr_buffer_reference *brs[2], *br;
char *bufs[2], *buf;
}
/* make a new btrb that combines the two buffers and a br to it. */
sz = szs[0] + szs[1];
- //PARA_CRIT_LOG("merging input buffers: (%zu, %zu) -> %zu\n",
- // szs[0], szs[1], sz);
buf = para_malloc(sz);
- /* TODO: Avoid this memcopy by introducing btr buffer pool. */
+ PARA_DEBUG_LOG("%s: memory merging input buffers: (%zu, %zu) -> %zu\n",
+ btrn->name, szs[0], szs[1], sz);
memcpy(buf, bufs[0], szs[0]);
memcpy(buf + szs[0], bufs[1], szs[1]);
- br = para_malloc(sizeof(*br));
+ br = para_calloc(sizeof(*br));
br->btrb = new_btrb(buf, sz);
br->btrb->refcount = 1;
- br->consumed = 0;
/* replace the first two refs by the new one */
btr_drop_buffer_reference(brs[0]);
para_list_add(&br->node, &btrn->input_queue);
return 2;
}
+
+void btr_merge(struct btr_node *btrn, size_t dest_size)
+{
+ if (need_buffer_pool_merge(btrn))
+ return merge_input_pool(btrn, dest_size);
+ for (;;) {
+ char *buf;
+ size_t len = btr_next_buffer(btrn, &buf);
+ if (len >= dest_size)
+ return;
+ PARA_DEBUG_LOG("input size = %zu < %zu = dest\n", len, dest_size);
+ if (merge_input(btrn) < 2)
+ return;
+ }
+}
+
+bool btr_eof(struct btr_node *btrn)
+{
+ char *buf;
+ size_t len = btr_next_buffer(btrn, &buf);
+
+ return (len == 0 && btr_no_parent(btrn));
+}
+
+void log_tree_recursively(struct btr_node *btrn, int loglevel, int depth)
+{
+ struct btr_node *ch;
+ const char spaces[] = " ", *space = spaces + 16 - depth;
+
+ if (depth > 16)
+ return;
+ para_log(loglevel, "%s%s\n", space, btrn->name);
+ FOR_EACH_CHILD(ch, btrn)
+ log_tree_recursively(ch, loglevel, depth + 1);
+}
+
+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)
+
+int btr_node_status(struct btr_node *btrn, size_t min_iqs,
+ enum btr_node_type type)
+{
+ size_t iqs;
+
+ assert(btrn);
+ if (type != BTR_NT_LEAF) {
+ if (btr_no_children(btrn))
+ return -E_BTR_NO_CHILD;
+ if (btr_bytes_pending(btrn) > BTRN_MAX_PENDING)
+ return 0;
+ }
+ if (type != BTR_NT_ROOT) {
+ if (btr_eof(btrn))
+ return -E_BTR_EOF;
+ iqs = btr_get_input_queue_size(btrn);
+ if (iqs == 0) /* we have a parent, because not eof */
+ return 0;
+ if (iqs < min_iqs && !btr_no_parent(btrn))
+ return 0;
+ }
+ return 1;
+}
+
+void btr_get_node_start(struct btr_node *btrn, struct timeval *tv)
+{
+ *tv = btrn->start;
+}
projects / paraslash.git / blobdiff