Exemplo n.º 1
0
/*
 * __wt_posix_file_fallocate --
 *	POSIX fallocate.
 */
int
__wt_posix_file_fallocate(WT_FILE_HANDLE *file_handle,
    WT_SESSION *wt_session, wt_off_t offset, wt_off_t len)
{
	/*
	 * The first fallocate call: figure out what fallocate call this system
	 * supports, if any.
	 *
	 * The function is configured as a locking fallocate call, so we know
	 * we're single-threaded through here. Set the nolock function first,
	 * then publish the NULL replacement to ensure the handle functions are
	 * always correct.
	 *
	 * We've seen Linux systems where posix_fallocate has corrupted
	 * existing file data (even though that is explicitly disallowed
	 * by POSIX). FreeBSD and Solaris support posix_fallocate, and
	 * so far we've seen no problems leaving it unlocked. Check for
	 * fallocate (and the system call version of fallocate) first to
	 * avoid locking on Linux if at all possible.
	 */
	if (__posix_std_fallocate(file_handle, wt_session, offset, len) == 0) {
		file_handle->fh_allocate_nolock = __posix_std_fallocate;
		WT_PUBLISH(file_handle->fh_allocate, NULL);
		return (0);
	}
	if (__posix_sys_fallocate(file_handle, wt_session, offset, len) == 0) {
		file_handle->fh_allocate_nolock = __posix_sys_fallocate;
		WT_PUBLISH(file_handle->fh_allocate, NULL);
		return (0);
	}
	if (__posix_posix_fallocate(
	    file_handle, wt_session, offset, len) == 0) {
#if defined(__linux__)
		file_handle->fh_allocate = __posix_posix_fallocate;
		WT_WRITE_BARRIER();
#else
		file_handle->fh_allocate_nolock = __posix_posix_fallocate;
		WT_PUBLISH(file_handle->fh_allocate, NULL);
#endif
		return (0);
	}

	file_handle->fh_allocate = NULL;
	WT_WRITE_BARRIER();
	return (ENOTSUP);
}
Exemplo n.º 2
0
/*
 * __wt_connection_open --
 *	Open a connection.
 */
int
__wt_connection_open(WT_CONNECTION_IMPL *conn, const char *cfg[])
{
	WT_SESSION_IMPL *session;

	/* Default session. */
	session = conn->default_session;
	WT_ASSERT(session, session->iface.connection == &conn->iface);

	/*
	 * Tell internal server threads to run: this must be set before opening
	 * any sessions.
	 */
	F_SET(conn, WT_CONN_SERVER_RUN | WT_CONN_LOG_SERVER_RUN);

	/* WT_SESSION_IMPL array. */
	WT_RET(__wt_calloc(session,
	    conn->session_size, sizeof(WT_SESSION_IMPL), &conn->sessions));
	WT_CACHE_LINE_ALIGNMENT_VERIFY(session, conn->sessions);

	/*
	 * Open the default session.  We open this before starting service
	 * threads because those may allocate and use session resources that
	 * need to get cleaned up on close.
	 */
	WT_RET(__wt_open_internal_session(
	    conn, "connection", false, 0, &session));

	/*
	 * The connection's default session is originally a static structure,
	 * swap that out for a more fully-functional session.  It's necessary
	 * to have this step: the session allocation code uses the connection's
	 * session, and if we pass a reference to the default session as the
	 * place to store the allocated session, things get confused and error
	 * handling can be corrupted.  So, we allocate into a stack variable
	 * and then assign it on success.
	 */
	conn->default_session = session;

	/*
	 * Publish: there must be a barrier to ensure the connection structure
	 * fields are set before other threads read from the pointer.
	 */
	WT_WRITE_BARRIER();

	/* Create the cache. */
	WT_RET(__wt_cache_create(session, cfg));

	/* Initialize transaction support. */
	WT_RET(__wt_txn_global_init(session, cfg));

	return (0);
}
Exemplo n.º 3
0
/*
 * __wt_insert_serial_func --
 *	Server function to add an WT_INSERT entry to the page.
 */
int
__wt_insert_serial_func(WT_SESSION_IMPL *session, void *args)
{
	WT_INSERT *new_ins, ***ins_stack;
	WT_INSERT_HEAD *inshead, **insheadp, **new_inslist, *new_inshead;
	WT_PAGE *page;
	uint32_t write_gen;
	u_int i, skipdepth;

	__wt_insert_unpack(args, &page, &write_gen, &insheadp,
	    &ins_stack, &new_inslist, &new_inshead, &new_ins, &skipdepth);

	/* Check the page's write-generation. */
	WT_RET(__wt_page_write_gen_check(session, page, write_gen));

	/*
	 * Publish: First, point the new WT_INSERT item's skiplist references
	 * to the next elements in the insert list, then flush memory.  Second,
	 * update the skiplist elements that reference the new WT_INSERT item,
	 * this ensures the list is never inconsistent.
	 */
	if ((inshead = *insheadp) == NULL)
		inshead = new_inshead;
	for (i = 0; i < skipdepth; i++)
		new_ins->next[i] = *ins_stack[i];
	WT_WRITE_BARRIER();
	for (i = 0; i < skipdepth; i++) {
		if (inshead->tail[i] == NULL ||
		    ins_stack[i] == &inshead->tail[i]->next[i])
			inshead->tail[i] = new_ins;
		*ins_stack[i] = new_ins;
	}

	__wt_insert_new_ins_taken(session, args, page);

	/*
	 * If the insert head does not yet have an insert list, our caller
	 * passed us one.
	 *
	 * NOTE: it is important to do this after the item has been added to
	 * the list.  Code can assume that if the list is set, it is non-empty.
	 */
	if (*insheadp == NULL) {
		WT_PUBLISH(*insheadp, new_inshead);
		__wt_insert_new_inshead_taken(session, args, page);
	}

	/*
	 * If the page does not yet have an insert array, our caller passed
	 * us one.
	 *
	 * NOTE: it is important to do this after publishing the list entry.
	 * Code can assume that if the array is set, it is non-empty.
	 */
	if (page->type == WT_PAGE_ROW_LEAF) {
		if (page->u.row.ins == NULL) {
			page->u.row.ins = new_inslist;
			__wt_insert_new_inslist_taken(session, args, page);
		}
	} else
		if (page->modify->update == NULL) {
			page->modify->update = new_inslist;
			__wt_insert_new_inslist_taken(session, args, page);
		}
	__wt_page_and_tree_modify_set(session, page);
	return (0);
}
Exemplo n.º 4
0
/*
 * __wt_col_append_serial_func --
 *	Server function to append an WT_INSERT entry to the tree.
 */
int
__wt_col_append_serial_func(WT_SESSION_IMPL *session, void *args)
{
	WT_BTREE *btree;
	WT_INSERT *ins, *new_ins, ***ins_stack, **next_stack;
	WT_INSERT_HEAD *inshead, **insheadp, **new_inslist, *new_inshead;
	WT_PAGE *page;
	uint64_t recno;
	uint32_t write_gen;
	u_int i, skipdepth;

	btree = S2BT(session);

	__wt_col_append_unpack(args,
	    &page, &write_gen, &insheadp, &ins_stack, &next_stack,
	    &new_inslist, &new_inshead, &new_ins, &skipdepth);

	/* Check the page's write-generation. */
	WT_RET(__wt_page_write_gen_check(session, page, write_gen));

	if ((inshead = *insheadp) == NULL)
		inshead = new_inshead;

	/*
	 * If the application specified a record number, there's a race: the
	 * application may have searched for the record, not found it, then
	 * called into the append code, and another thread might have added
	 * the record.  Fortunately, we're in the right place because if the
	 * record didn't exist at some point, it can only have been created
	 * on this list.  Search for the record, if specified.
	 */
	if ((recno = WT_INSERT_RECNO(new_ins)) == 0)
		recno = WT_INSERT_RECNO(new_ins) = ++btree->last_recno;

	ins = __col_insert_search(inshead, ins_stack, next_stack, recno);

	/* If we find the record number, there's been a race. */
	if (ins != NULL && WT_INSERT_RECNO(ins) == recno)
		WT_RET(WT_RESTART);

	/*
	 * Publish: First, point the new WT_INSERT item's skiplist references
	 * to the next elements in the insert list, then flush memory.  Second,
	 * update the skiplist elements that reference the new WT_INSERT item,
	 * this ensures the list is never inconsistent.
	 */
	for (i = 0; i < skipdepth; i++)
		new_ins->next[i] = *ins_stack[i];
	WT_WRITE_BARRIER();
	for (i = 0; i < skipdepth; i++) {
		if (inshead->tail[i] == NULL ||
		    ins_stack[i] == &inshead->tail[i]->next[i])
			inshead->tail[i] = new_ins;
		*ins_stack[i] = new_ins;
	}

	__wt_col_append_new_ins_taken(args);

	/*
	 * If the insert head does not yet have an insert list, our caller
	 * passed us one.
	 *
	 * NOTE: it is important to do this after the item has been added to
	 * the list.  Code can assume that if the list is set, it is non-empty.
	 */
	if (*insheadp == NULL) {
		WT_PUBLISH(*insheadp, new_inshead);
		__wt_col_append_new_inshead_taken(args);
	}

	/*
	 * If the page does not yet have an insert array, our caller passed
	 * us one.
	 *
	 * NOTE: it is important to do this after publishing the list entry.
	 * Code can assume that if the array is set, it is non-empty.
	 */
	if (page->modify->append == NULL) {
		page->modify->append = new_inslist;
		__wt_col_append_new_inslist_taken(args);
	}

	/*
	 * If we don't find the record, check to see if we extended the file,
	 * and update the last record number.
	 */
	if (recno > btree->last_recno)
		btree->last_recno = recno;

	__wt_page_and_tree_modify_set(session, page);
	return (0);
}