From patchwork Mon Dec 21 17:08:37 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 559664 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 88A121402D6 for ; Tue, 22 Dec 2015 04:30:19 +1100 (AEDT) Received: from localhost ([::1]:46494 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aB4Hp-0006IR-6S for incoming@patchwork.ozlabs.org; Mon, 21 Dec 2015 12:30:17 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51658) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aB3xL-0007KE-O3 for qemu-devel@nongnu.org; Mon, 21 Dec 2015 12:09:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aB3xI-0006fk-Jt for qemu-devel@nongnu.org; Mon, 21 Dec 2015 12:09:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36106) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aB3xI-0006fe-9J; Mon, 21 Dec 2015 12:09:04 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 010BE40C3B; Mon, 21 Dec 2015 17:09:03 +0000 (UTC) Received: from red.redhat.com (ovpn-113-139.phx2.redhat.com [10.3.113.139]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tBLH8geB008283; Mon, 21 Dec 2015 12:09:03 -0500 From: Eric Blake To: qemu-devel@nongnu.org Date: Mon, 21 Dec 2015 10:08:37 -0700 Message-Id: <1450717720-9627-33-git-send-email-eblake@redhat.com> In-Reply-To: <1450717720-9627-1-git-send-email-eblake@redhat.com> References: <1450717720-9627-1-git-send-email-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: "Michael S. Tsirkin" , armbru@redhat.com, Michael Roth , Alexander Graf , "open list:sPAPR pseries" , Paolo Bonzini , Luiz Capitulino , =?UTF-8?q?Andreas=20F=C3=A4rber?= , David Gibson Subject: [Qemu-devel] [PATCH v8 32/35] qapi: Split visit_end_struct() into pieces X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org As mentioned in previous patches, we want to call visit_end_struct() functions unconditionally, so that visitors can release resources tied up since the matching visit_start_struct() without also having to worry about error priority if more than one error occurs. Even though error_propagate() can be safely used to ignore a second error during cleanup caused by a first error, it is simpler if the cleanup cannot set an error, and we instead split the task of checking that an input visitor has no unvisited input as a new function visit_check_struct(), called only if all prior steps are successful. Generated code has diffs resembling: |@@ -59,10 +59,12 @@ void visit_type_ACPIOSTInfo(Visitor *v, | goto out_obj; | } | visit_type_ACPIOSTInfo_fields(v, obj, &err); |+ if (err) { |+ goto out_obj; |+ } |+ visit_check_struct(v, &err); | out_obj: |- error_propagate(errp, err); |- err = NULL; |- visit_end_struct(v, &err); |+ visit_end_struct(v); | out: Signed-off-by: Eric Blake Reviewed-by: Marc-André Lureau --- v8: rebase to 'name' motion v7: rebase to earlier changes v6: new patch, revised version of RFC based on discussion of v5 7/46 --- hmp.c | 7 ++++--- hw/ppc/spapr_drc.c | 3 ++- hw/virtio/virtio-balloon.c | 12 ++++++------ include/qapi/visitor-impl.h | 4 +++- include/qapi/visitor.h | 13 ++++++++++--- qapi/opts-visitor.c | 17 +++++++++++++++-- qapi/qapi-dealloc-visitor.c | 2 +- qapi/qapi-visit-core.c | 11 +++++++++-- qapi/qmp-input-visitor.c | 34 +++++++++++++++++++--------------- qapi/qmp-output-visitor.c | 2 +- qom/object.c | 5 ++--- scripts/qapi-event.py | 3 ++- scripts/qapi-visit.py | 9 ++++----- vl.c | 11 +++++------ 14 files changed, 83 insertions(+), 50 deletions(-) diff --git a/hmp.c b/hmp.c index 159dfc4..7da9896 100644 --- a/hmp.c +++ b/hmp.c @@ -1698,13 +1698,14 @@ void hmp_object_add(Monitor *mon, const QDict *qdict) } object_add(type, id, pdict, v, &err); - -out_end: - visit_end_struct(v, &err_end); + visit_check_struct(v, &err_end); if (!err && err_end) { qmp_object_del(id, NULL); } error_propagate(&err, err_end); + +out_end: + visit_end_struct(v); out_clean: opts_visitor_cleanup(ov); diff --git a/hw/ppc/spapr_drc.c b/hw/ppc/spapr_drc.c index 4c8a0ef..91becc2 100644 --- a/hw/ppc/spapr_drc.c +++ b/hw/ppc/spapr_drc.c @@ -287,11 +287,12 @@ static void prop_get_fdt(Object *obj, Visitor *v, const char *name, case FDT_END_NODE: /* shouldn't ever see an FDT_END_NODE before FDT_BEGIN_NODE */ g_assert(fdt_depth > 0); - visit_end_struct(v, &err); + visit_check_struct(v, &err); if (err) { error_propagate(errp, err); return; } + visit_end_struct(v); fdt_depth--; break; case FDT_PROP: { diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index 24ecd87..cefd43f 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -136,15 +136,15 @@ static void balloon_stats_get_all(Object *obj, Visitor *v, const char *name, goto out_nested; } } + visit_check_struct(v, &err); out_nested: - error_propagate(errp, err); - err = NULL; - visit_end_struct(v, &err); + visit_end_struct(v); + if (!err) { + visit_check_struct(v, &err); + } out_end: - error_propagate(errp, err); - err = NULL; - visit_end_struct(v, &err); + visit_end_struct(v); out: error_propagate(errp, err); } diff --git a/include/qapi/visitor-impl.h b/include/qapi/visitor-impl.h index 4557e99..08b1b94 100644 --- a/include/qapi/visitor-impl.h +++ b/include/qapi/visitor-impl.h @@ -28,8 +28,10 @@ struct Visitor * currently visit structs). */ void (*start_struct)(Visitor *v, const char *name, void **obj, size_t size, Error **errp); + /* May be NULL; most useful for input visitors. */ + void (*check_struct)(Visitor *v, Error **errp); /* Must be provided if start_struct is present. */ - void (*end_struct)(Visitor *v, Error **errp); + void (*end_struct)(Visitor *v); /* May be NULL; most useful for input visitors. */ void (*start_implicit_struct)(Visitor *v, void **obj, size_t size, diff --git a/include/qapi/visitor.h b/include/qapi/visitor.h index d7a0110..e5dcde4 100644 --- a/include/qapi/visitor.h +++ b/include/qapi/visitor.h @@ -68,12 +68,19 @@ typedef struct GenericList void visit_start_struct(Visitor *v, const char *name, void **obj, size_t size, Error **errp); /** + * Prepare for completing a struct visit. + * Should be called prior to visit_end_struct() if all other intermediate + * visit steps were successful, to allow the caller one last chance to + * report errors such as remaining data that was not consumed by the visit. + */ +void visit_check_struct(Visitor *v, Error **errp); +/** * Complete a struct visit started earlier. * Must be called after any successful use of visit_start_struct(), * even if intermediate processing was skipped due to errors, to allow * the backend to release any resources. */ -void visit_end_struct(Visitor *v, Error **errp); +void visit_end_struct(Visitor *v); /** * Prepare to visit an implicit struct. @@ -96,8 +103,8 @@ void visit_start_implicit_struct(Visitor *v, void **obj, size_t size, * Must be called after any successful use of visit_start_implicit_struct(), * even if intermediate processing was skipped due to errors, to allow * the backend to release any resources. Unlike visit_end_struct(), this - * does not need to check for errors (detection of unused keys is only - * possible for the overall struct, not a subset). + * does not need a counterpart function to check for errors (detection of + * unused keys is only possible for the overall struct, not a subset). */ void visit_end_implicit_struct(Visitor *v); diff --git a/qapi/opts-visitor.c b/qapi/opts-visitor.c index df312e6..b469573 100644 --- a/qapi/opts-visitor.c +++ b/qapi/opts-visitor.c @@ -157,13 +157,13 @@ opts_start_struct(Visitor *v, const char *name, void **obj, static void -opts_end_struct(Visitor *v, Error **errp) +opts_check_struct(Visitor *v, Error **errp) { OptsVisitor *ov = to_ov(v); GHashTableIter iter; GQueue *any; - if (--ov->depth > 0) { + if (ov->depth > 0) { return; } @@ -175,6 +175,18 @@ opts_end_struct(Visitor *v, Error **errp) first = g_queue_peek_head(any); error_setg(errp, QERR_INVALID_PARAMETER, first->name); } +} + + +static void +opts_end_struct(Visitor *v) +{ + OptsVisitor *ov = DO_UPCAST(OptsVisitor, visitor, v); + + if (--ov->depth > 0) { + return; + } + g_hash_table_destroy(ov->unprocessed_opts); ov->unprocessed_opts = NULL; if (ov->fake_id_opt) { @@ -506,6 +518,7 @@ opts_visitor_new(const QemuOpts *opts) ov = g_malloc0(sizeof *ov); ov->visitor.start_struct = &opts_start_struct; + ov->visitor.check_struct = &opts_check_struct; ov->visitor.end_struct = &opts_end_struct; ov->visitor.start_list = &opts_start_list; diff --git a/qapi/qapi-dealloc-visitor.c b/qapi/qapi-dealloc-visitor.c index 1a54864..a89e6d1 100644 --- a/qapi/qapi-dealloc-visitor.c +++ b/qapi/qapi-dealloc-visitor.c @@ -65,7 +65,7 @@ static void qapi_dealloc_start_struct(Visitor *v, const char *name, void **obj, qapi_dealloc_push(qov, obj); } -static void qapi_dealloc_end_struct(Visitor *v, Error **errp) +static void qapi_dealloc_end_struct(Visitor *v) { QapiDeallocVisitor *qov = to_qov(v); void **obj = qapi_dealloc_pop(qov); diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c index 3360cdf..9506a02 100644 --- a/qapi/qapi-visit-core.c +++ b/qapi/qapi-visit-core.c @@ -36,9 +36,16 @@ void visit_start_struct(Visitor *v, const char *name, void **obj, v->start_struct(v, name, obj, size, errp); } -void visit_end_struct(Visitor *v, Error **errp) +void visit_check_struct(Visitor *v, Error **errp) { - v->end_struct(v, errp); + if (v->check_struct) { + v->check_struct(v, errp); + } +} + +void visit_end_struct(Visitor *v) +{ + v->end_struct(v); } void visit_start_implicit_struct(Visitor *v, void **obj, size_t size, diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c index 09cd2f1..52d8c9a 100644 --- a/qapi/qmp-input-visitor.c +++ b/qapi/qmp-input-visitor.c @@ -89,8 +89,10 @@ static void qmp_input_push(QmpInputVisitor *qiv, QObject *obj, Error **errp) } -static void qmp_input_pop(QmpInputVisitor *qiv, Error **errp) +static void qmp_input_check_struct(Visitor *v, Error **errp) { + QmpInputVisitor *qiv = to_qiv(v); + assert(qiv->nb_stack > 0); if (qiv->strict) { @@ -103,6 +105,19 @@ static void qmp_input_pop(QmpInputVisitor *qiv, Error **errp) if (g_hash_table_iter_next(&iter, (void **)&key, NULL)) { error_setg(errp, QERR_QMP_EXTRA_MEMBER, key); } + } + } +} + +static void qmp_input_pop(Visitor *v) +{ + QmpInputVisitor *qiv = to_qiv(v); + + assert(qiv->nb_stack > 0); + + if (qiv->strict) { + GHashTable * const top_ht = qiv->stack[qiv->nb_stack - 1].h; + if (top_ht) { g_hash_table_unref(top_ht); } } @@ -134,12 +149,6 @@ static void qmp_input_start_struct(Visitor *v, const char *name, void **obj, } } -static void qmp_input_end_struct(Visitor *v, Error **errp) -{ - QmpInputVisitor *qiv = to_qiv(v); - - qmp_input_pop(qiv, errp); -} static void qmp_input_start_implicit_struct(Visitor *v, void **obj, size_t size, Error **errp) @@ -193,12 +202,6 @@ static GenericList *qmp_input_next_list(Visitor *v, GenericList **list, return entry; } -static void qmp_input_end_list(Visitor *v) -{ - QmpInputVisitor *qiv = to_qiv(v); - - qmp_input_pop(qiv, &error_abort); -} static void qmp_input_get_next_type(Visitor *v, const char *name, QType *type, bool promote_int, Error **errp) @@ -342,11 +345,12 @@ QmpInputVisitor *qmp_input_visitor_new(QObject *obj) v = g_malloc0(sizeof(*v)); v->visitor.start_struct = qmp_input_start_struct; - v->visitor.end_struct = qmp_input_end_struct; + v->visitor.check_struct = qmp_input_check_struct; + v->visitor.end_struct = qmp_input_pop; v->visitor.start_implicit_struct = qmp_input_start_implicit_struct; v->visitor.start_list = qmp_input_start_list; v->visitor.next_list = qmp_input_next_list; - v->visitor.end_list = qmp_input_end_list; + v->visitor.end_list = qmp_input_pop; v->visitor.type_enum = input_type_enum; v->visitor.type_int64 = qmp_input_type_int64; v->visitor.type_uint64 = qmp_input_type_uint64; diff --git a/qapi/qmp-output-visitor.c b/qapi/qmp-output-visitor.c index f2c39c5..5a1767b 100644 --- a/qapi/qmp-output-visitor.c +++ b/qapi/qmp-output-visitor.c @@ -117,7 +117,7 @@ static void qmp_output_start_struct(Visitor *v, const char *name, void **obj, qmp_output_push(qov, dict); } -static void qmp_output_end_struct(Visitor *v, Error **errp) +static void qmp_output_end_struct(Visitor *v) { QmpOutputVisitor *qov = to_qov(v); qmp_output_pop(qov); diff --git a/qom/object.c b/qom/object.c index f0ab9aa..0d0b386 100644 --- a/qom/object.c +++ b/qom/object.c @@ -1906,10 +1906,9 @@ static void property_get_tm(Object *obj, Visitor *v, const char *name, if (err) { goto out_end; } + visit_check_struct(v, &err); out_end: - error_propagate(errp, err); - err = NULL; - visit_end_struct(v, errp); + visit_end_struct(v); out: error_propagate(errp, err); diff --git a/scripts/qapi-event.py b/scripts/qapi-event.py index 8d634bd..e694b1b 100644 --- a/scripts/qapi-event.py +++ b/scripts/qapi-event.py @@ -71,8 +71,9 @@ def gen_event_send(name, arg_type): ret += gen_visit_fields(arg_type.members, need_cast=True, label='out_obj') ret += mcgen(''' + visit_check_struct(v, &err); out_obj: - visit_end_struct(v, &err); + visit_end_struct(v); if (err) { goto out; } diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py index 7a44c13..8039b97 100644 --- a/scripts/qapi-visit.py +++ b/scripts/qapi-visit.py @@ -255,8 +255,7 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error visit_type_%(c_name)s_fields(v, %(cast)sobj, &err); ''', c_name=type_name, cast=cast) - if variants: - ret += gen_err_check(label='out_obj') + ret += gen_err_check(label='out_obj') if variants: ret += mcgen(''' @@ -293,12 +292,12 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error abort(); } ''') + ret += gen_err_check(label='out_obj') ret += mcgen(''' + visit_check_struct(v, &err); out_obj: - error_propagate(errp, err); - err = NULL; - visit_end_struct(v, &err); + visit_end_struct(v); out: error_propagate(errp, err); } diff --git a/vl.c b/vl.c index 22064f1..200f3d5 100644 --- a/vl.c +++ b/vl.c @@ -2848,11 +2848,10 @@ static int object_create(void *opaque, QemuOpts *opts, Error **errp) qdict_del(pdict, "qom-type"); visit_type_str(v, "qom-type", &type, &err); if (err) { - goto out; + goto out_end; } if (!type_predicate(type)) { - visit_end_struct(v, NULL); - goto out; + goto out_end; } qdict_del(pdict, "id"); @@ -2862,14 +2861,14 @@ static int object_create(void *opaque, QemuOpts *opts, Error **errp) } object_add(type, id, pdict, v, &err); - -out_end: - visit_end_struct(v, &err_end); + visit_check_struct(v, &err_end); if (!err && err_end) { qmp_object_del(id, NULL); } error_propagate(&err, err_end); +out_end: + visit_end_struct(v); out: opts_visitor_cleanup(ov);