Zhang Chen <[email protected]> writes: > Extend the 'IOThreadInfo' structure to include attachment metrics. > This allows users to monitor the associated devices by identify them > by their QOM paths.
Should we mention block nodes and monitors, too? > > New fields added to IOThreadInfo: > @holders: IOThreadHolder of the devices currently associated with > this iothread. Users can pre-allocate multiple iothread objects > to serve as a persistent thread pool. When a device is hot-unplugged, > it is detached from its iothread, but the iothread remains available, > allowing future hot-plugged devices to attach to it. (Since 11.1) > > These fields are also exposed via the Human Monitor Interface (HMP) > command 'info iothreads' to assist with manual debugging and > performance tuning. > > Signed-off-by: Zhang Chen <[email protected]> > --- > iothread.c | 22 ++++++++++++++++++++++ > monitor/hmp-cmds.c | 26 ++++++++++++++++++++++++++ > qapi/misc.json | 11 +++++++++++ > 3 files changed, 59 insertions(+) > > diff --git a/iothread.c b/iothread.c > index a85e960e45..5949785b32 100644 > --- a/iothread.c > +++ b/iothread.c > @@ -24,6 +24,8 @@ > #include "qemu/error-report.h" > #include "qemu/rcu.h" > #include "qemu/main-loop.h" > +#include "qapi/clone-visitor.h" > +#include "qapi/qapi-visit-misc.h" > > /* > * iothread_ref: > @@ -119,6 +121,25 @@ static void iothread_unref(IOThread *iothread, const > IOThreadHolder *holder) > object_unref(OBJECT(iothread)); > } > > +static IOThreadHolderList *iothread_get_holders_list(IOThread *iothread) > +{ > + IOThreadHolderList *head = NULL; > + IOThreadHolderList **prev = &head; > + GList *l; > + > + for (l = iothread->holders; l; l = l->next) { > + IOThreadHolder *src = l->data; > + IOThreadHolderList *entry = g_new0(IOThreadHolderList, 1); > + > + entry->value = QAPI_CLONE(IOThreadHolder, src); > + > + *prev = entry; > + prev = &entry->next; > + } If iothread->holders was a IOThreadHolderList instead of a GList, this loop could be QAPI_CLONE(IOThreadHolderList, iothread->holders) instead. > + > + return head; > +} > + > static void *iothread_run(void *opaque) > { > IOThread *iothread = opaque; > @@ -488,6 +509,7 @@ static int query_one_iothread(Object *object, void > *opaque) > info = g_new0(IOThreadInfo, 1); > info->id = iothread_get_id(iothread); > info->thread_id = iothread->thread_id; > + info->holders = iothread_get_holders_list(iothread); > info->poll_max_ns = iothread->poll_max_ns; > info->poll_grow = iothread->poll_grow; > info->poll_shrink = iothread->poll_shrink; > diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c > index 443b8c785d..1b5883147b 100644 > --- a/monitor/hmp-cmds.c > +++ b/monitor/hmp-cmds.c > @@ -237,11 +237,37 @@ void hmp_info_iothreads(Monitor *mon, const QDict > *qdict) > IOThreadInfoList *info_list = qmp_query_iothreads(NULL); > IOThreadInfoList *info; > IOThreadInfo *value; > + IOThreadHolderList *h; > > for (info = info_list; info; info = info->next) { > value = info->value; > monitor_printf(mon, "%s:\n", value->id); > monitor_printf(mon, " thread_id=%" PRId64 "\n", value->thread_id); > + monitor_printf(mon, " holders="); > + if (value->holders) { > + for (h = value->holders; h; h = h->next) { > + IOThreadHolder *holder = h->value; > + > + switch (holder->type) { > + case IO_THREAD_HOLDER_KIND_BLOCK_NODE: > + monitor_printf(mon, "[block-node: %s]", > + holder->u.block_node.node_name); > + break; > + case IO_THREAD_HOLDER_KIND_QOM_OBJECT: > + monitor_printf(mon, "[qom-path: %s]", > + holder->u.qom_object.qom_path); > + break; > + case IO_THREAD_HOLDER_KIND_MONITOR_NAME: > + monitor_printf(mon, "[monitor-name: %s]", > + holder->u.monitor_name.monitor_name); > + break; > + default: > + monitor_printf(mon, "[unknown]"); > + break; > + } > + } > + monitor_printf(mon, "\n"); > + } > monitor_printf(mon, " poll-max-ns=%" PRId64 "\n", > value->poll_max_ns); > monitor_printf(mon, " poll-grow=%" PRId64 "\n", value->poll_grow); > monitor_printf(mon, " poll-shrink=%" PRId64 "\n", > value->poll_shrink); > diff --git a/qapi/misc.json b/qapi/misc.json > index d9f82f0922..4c16be3fd4 100644 > --- a/qapi/misc.json > +++ b/qapi/misc.json > @@ -137,6 +137,13 @@ > # > # @thread-id: ID of the underlying host thread > # > +# @holders: IOThreadHolder of the devices currently associated with This is rendered like • holders ([IOThreadHolder]) – IOThreadHolder of the devices currently associated with Better use something like # @holders: the devices currently associated with ... I'm not sure about "devices", though. It's QOM objects, block nodes, and monitors. Perhaps the QOM objects are all be devices (subtypes of TYPE_DEVICE), but I'd have to dig through your patches to be sure. Does it matter? > +# this iothread. Users can pre-allocate multiple iothread objects > +# to serve as a persistent thread pool. When a device is > +# hot-unplugged, it is detached from its iothread, but the > +# iothread remains available, allowing future hot-plugged devices > +# to attach to it. (Since 11.1) This may need to be rewritten with block nodes and monitors in mind. > +# > # @poll-max-ns: maximum polling time in ns, 0 means polling is > # disabled (since 2.9) > # > @@ -159,6 +166,7 @@ > { 'struct': 'IOThreadInfo', > 'data': {'id': 'str', > 'thread-id': 'int', > + 'holders': ['IOThreadHolder'], > 'poll-max-ns': 'int', > 'poll-grow': 'int', > 'poll-shrink': 'int', > @@ -185,6 +193,8 @@ > # { > # "id":"iothread0", > # "thread-id":3134, > +# "holders":[{"qom-path": > "/machine/peripheral/blk1/virtio-backend", "type": "qom-object"}, > +# {"qom-path": > "/machine/peripheral/blk0/virtio-backend", "type": "qom-object"}], > # "poll-max-ns":32768, > # "poll-grow":0, > # "poll-shrink":0, > @@ -193,6 +203,7 @@ > # { > # "id":"iothread1", > # "thread-id":3135, > +# "holders":[{"qom-path": > "/machine/peripheral/blk2/virtio-backend", "type": "qom-object"}], > # "poll-max-ns":32768, > # "poll-grow":0, > # "poll-shrink":0, Would it be useful if one of these examples was a block node?
