{
bool fixed_iothread = export->has_fixed_iothread && export->fixed_iothread;
bool allow_inactive = export->has_allow_inactive && export->allow_inactive;
+ bool multithread = export->iothread &&
+ export->iothread->type == QTYPE_QLIST;
const BlockExportDriver *drv;
BlockExport *exp = NULL;
BlockDriverState *bs;
BlockBackend *blk = NULL;
AioContext *ctx;
+ AioContext **multithread_ctxs = NULL;
+ size_t multithread_count = 0;
uint64_t perm;
int ret;
GLOBAL_STATE_CODE();
+ if (fixed_iothread && multithread) {
+ error_setg(errp,
+ "Cannot use fixed-iothread for a multi-threaded export");
+ return NULL;
+ }
+
if (!id_wellformed(export->id)) {
error_setg(errp, "Invalid block export id");
return NULL;
ctx = bdrv_get_aio_context(bs);
- if (export->iothread) {
+ /* Move the BDS to the target I/O thread, if it is a single one */
+ if (export->iothread && !multithread) {
+ const char *iothread_id = export->iothread->u.single;
IOThread *iothread;
AioContext *new_ctx;
Error **set_context_errp;
- iothread = iothread_by_id(export->iothread);
+ iothread = iothread_by_id(iothread_id);
if (!iothread) {
- error_setg(errp, "iothread \"%s\" not found", export->iothread);
+ error_setg(errp, "iothread \"%s\" not found", iothread_id);
goto fail;
}
} else if (fixed_iothread) {
goto fail;
}
+ } else if (multithread) {
+ strList *iothread_list = export->iothread->u.multi;
+ size_t i;
+
+ multithread_count = 0;
+ for (strList *e = iothread_list; e; e = e->next) {
+ multithread_count++;
+ }
+
+ if (multithread_count == 0) {
+ error_setg(errp, "The set of I/O threads must not be empty");
+ return NULL;
+ }
+
+ multithread_ctxs = g_new(AioContext *, multithread_count);
+ i = 0;
+ for (strList *e = iothread_list; e; e = e->next) {
+ IOThread *iothread = iothread_by_id(e->value);
+
+ if (!iothread) {
+ error_setg(errp, "iothread \"%s\" not found", e->value);
+ goto fail;
+ }
+ multithread_ctxs[i++] = iothread_get_aio_context(iothread);
+ }
+ assert(i == multithread_count);
}
bdrv_graph_rdlock_main_loop();
.blk = blk,
};
- ret = drv->create(exp, export, errp);
+ ret = drv->create(exp, export, multithread_ctxs, multithread_count, errp);
if (ret < 0) {
goto fail;
}
assert(exp->blk != NULL);
QLIST_INSERT_HEAD(&block_exports, exp, next);
+ g_free(multithread_ctxs);
return exp;
fail:
g_free(exp->id);
g_free(exp);
}
+ g_free(multithread_ctxs);
return NULL;
}
static int fuse_export_create(BlockExport *blk_exp,
BlockExportOptions *blk_exp_args,
+ AioContext *const *multithread,
+ size_t mt_count,
Error **errp)
{
ERRP_GUARD(); /* ensure clean-up even with error_fatal */
assert(blk_exp_args->type == BLOCK_EXPORT_TYPE_FUSE);
+ if (multithread) {
+ error_setg(errp, "FUSE export does not support multi-threading");
+ return -EINVAL;
+ }
+
/* For growable and writable exports, take the RESIZE permission */
if (args->growable || blk_exp_args->writable) {
uint64_t blk_perm, blk_shared_perm;
};
static int vduse_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
+ AioContext *const *multithread, size_t mt_count,
Error **errp)
{
VduseBlkExport *vblk_exp = container_of(exp, VduseBlkExport, export);
return -EINVAL;
}
}
+
+ if (multithread) {
+ error_setg(errp, "vduse-blk export does not support multi-threading");
+ return -EINVAL;
+ }
+
vblk_exp->num_queues = num_queues;
vblk_exp->handler.blk = exp->blk;
vblk_exp->handler.serial = g_strdup(vblk_opts->serial ?: "");
};
static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
+ AioContext *const *multithread, size_t mt_count,
Error **errp)
{
VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
error_setg(errp, "num-queues must be greater than 0");
return -EINVAL;
}
+
+ if (multithread) {
+ error_setg(errp,
+ "vhost-user-blk export does not support multi-threading");
+ return -EINVAL;
+ }
+
vexp->handler.blk = exp->blk;
vexp->handler.serial = g_strdup("vhost_user_blk");
vexp->handler.logical_block_size = logical_block_size;
/* True if the export type supports running on an inactive node */
bool supports_inactive;
- /* Creates and starts a new block export */
- int (*create)(BlockExport *, BlockExportOptions *, Error **);
+ /*
+ * Creates and starts a new block export.
+ *
+ * If the user passed a set of I/O threads for multi-threading, @multithread
+ * is a list of the @multithread_count corresponding contexts (freed by the
+ * caller). Note that @exp->ctx has no relation to that list.
+ */
+ int (*create)(BlockExport *exp, BlockExportOptions *opts,
+ AioContext *const *multithread, size_t multithread_count,
+ Error **errp);
/*
* Frees a removed block export. This function is only called after all
};
static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
+ AioContext *const *multithread, size_t mt_count,
Error **errp)
{
NBDExport *exp = container_of(blk_exp, NBDExport, common);
return -EEXIST;
}
+ if (multithread) {
+ error_setg(errp, "NBD export does not support multi-threading");
+ return -EINVAL;
+ }
+
size = blk_getlength(blk);
if (size < 0) {
error_setg_errno(errp, -size,
# to the export before completion is signalled. (since: 5.2;
# default: false)
#
-# @iothread: The name of the iothread object where the export will
-# run. The default is to use the thread currently associated with
-# the block node. (since: 5.2)
+# @iothread: The name(s) of one or more iothread object(s) where the
+# export will run. The default is to use the thread currently
+# associated with the block node. (since: 5.2; multi-threading
+# since 10.1)
#
# @fixed-iothread: True prevents the block node from being moved to
# another thread while the export is active. If true and
# @iothread is given, export creation fails if the block node
-# cannot be moved to the iothread. The default is false.
+# cannot be moved to the iothread. Must not be true when giving
+# multiple iothreads for @iothread. The default is false.
# (since: 5.2)
#
# @allow-inactive: If true, the export allows the exported node to be
'base': { 'type': 'BlockExportType',
'id': 'str',
'*fixed-iothread': 'bool',
- '*iothread': 'str',
+ '*iothread': 'BlockExportIothreads',
'node-name': 'str',
'*writable': 'bool',
'*writethrough': 'bool',
'if': 'CONFIG_VDUSE_BLK_EXPORT' }
} }
+##
+# @BlockExportIothreads:
+#
+# Specify a single or multiple I/O threads in which to run a block
+# export's I/O.
+#
+# @single: Run the export's I/O in the given single I/O thread.
+#
+# @multi: Use multi-threading across the given set of I/O threads,
+# which must not be empty. Note: Passing a single I/O thread via
+# this variant is still treated as multi-threading, which is
+# different from using the @single variant. In particular, even
+# if there only is a single I/O thread in the set, export types
+# that do not support multi-threading will generally reject this
+# variant, and BlockExportOptions.fixed-iothread is always
+# incompatible with it.
+#
+# Since: 10.1
+##
+{ 'alternate': 'BlockExportIothreads',
+ 'data': {
+ 'single': 'str',
+ 'multi': ['str'] } }
+
##
# @block-export-add:
#
projects / thirdparty / qemu.git / commitdiff
