From patchwork Mon Jul 19 17:26:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 1507165 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=AukPSKSb; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4GT86x3y2lz9sRf for ; Tue, 20 Jul 2021 03:32:25 +1000 (AEST) Received: from localhost ([::1]:42940 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m5X7v-0006Hf-Ax for incoming@patchwork.ozlabs.org; Mon, 19 Jul 2021 13:32:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45388) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m5X33-0005H3-Pb for qemu-devel@nongnu.org; Mon, 19 Jul 2021 13:27:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38808) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m5X31-0003er-U4 for qemu-devel@nongnu.org; Mon, 19 Jul 2021 13:27:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626715639; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Pmc8fK8KoNKCoLW2UsEY+/ylkpVsysQtUC9Fe+pl91g=; b=AukPSKSbieEutJYMybaktwS/L0xZ57dH1/Rn4Qek4X1X1bj8LBBFQ+RAXHj60OEV7JDNJx 1gAPDRYmpw7/5OhJm+t/m6+5m2+QTz9MGG5Qy1o8zmH++zmCuxu7oThEWH3mdMwKOrPs7D VJ61bAzalyLAGzpUo3eVG8oOlwKM53E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-258-WhH4k3MzNeqgErPwYRxZKA-1; Mon, 19 Jul 2021 13:27:15 -0400 X-MC-Unique: WhH4k3MzNeqgErPwYRxZKA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A9BD91084F4B; Mon, 19 Jul 2021 17:27:14 +0000 (UTC) Received: from localhost (ovpn-112-59.ams2.redhat.com [10.36.112.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EE6DD19C44; Mon, 19 Jul 2021 17:27:13 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PULL 6/6] blkdebug: protect rules and suspended_reqs with a lock Date: Mon, 19 Jul 2021 19:26:58 +0200 Message-Id: <20210719172658.715442-7-mreitz@redhat.com> In-Reply-To: <20210719172658.715442-1-mreitz@redhat.com> References: <20210719172658.715442-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.469, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Peter Maydell , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Emanuele Giuseppe Esposito First, categorize the structure fields to identify what needs to be protected and what doesn't. We essentially need to protect only .state, and the 3 lists in BDRVBlkdebugState. Then, add the lock and mark the functions accordingly. Co-developed-by: Paolo Bonzini Signed-off-by: Emanuele Giuseppe Esposito Message-Id: <20210614082931.24925-7-eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy Signed-off-by: Max Reitz --- block/blkdebug.c | 49 ++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 39 insertions(+), 10 deletions(-) diff --git a/block/blkdebug.c b/block/blkdebug.c index b47c3fd97c..8b67554bec 100644 --- a/block/blkdebug.c +++ b/block/blkdebug.c @@ -38,24 +38,27 @@ #include "qapi/qobject-input-visitor.h" #include "sysemu/qtest.h" +/* All APIs are thread-safe */ + typedef struct BDRVBlkdebugState { - int state; + /* IN: initialized in blkdebug_open() and never changed */ uint64_t align; uint64_t max_transfer; uint64_t opt_write_zero; uint64_t max_write_zero; uint64_t opt_discard; uint64_t max_discard; - + char *config_file; /* For blkdebug_refresh_filename() */ + /* initialized in blkdebug_parse_perms() */ uint64_t take_child_perms; uint64_t unshare_child_perms; - /* For blkdebug_refresh_filename() */ - char *config_file; - + /* State. Protected by lock */ + int state; QLIST_HEAD(, BlkdebugRule) rules[BLKDBG__MAX]; QSIMPLEQ_HEAD(, BlkdebugRule) active_rules; QLIST_HEAD(, BlkdebugSuspendedReq) suspended_reqs; + QemuMutex lock; } BDRVBlkdebugState; typedef struct BlkdebugAIOCB { @@ -64,8 +67,11 @@ typedef struct BlkdebugAIOCB { } BlkdebugAIOCB; typedef struct BlkdebugSuspendedReq { + /* IN: initialized in suspend_request() */ Coroutine *co; char *tag; + + /* List entry protected BDRVBlkdebugState's lock */ QLIST_ENTRY(BlkdebugSuspendedReq) next; } BlkdebugSuspendedReq; @@ -77,6 +83,7 @@ enum { }; typedef struct BlkdebugRule { + /* IN: initialized in add_rule() or blkdebug_debug_breakpoint() */ BlkdebugEvent event; int action; int state; @@ -95,6 +102,8 @@ typedef struct BlkdebugRule { char *tag; } suspend; } options; + + /* List entries protected BDRVBlkdebugState's lock */ QLIST_ENTRY(BlkdebugRule) next; QSIMPLEQ_ENTRY(BlkdebugRule) active_next; } BlkdebugRule; @@ -244,11 +253,14 @@ static int add_rule(void *opaque, QemuOpts *opts, Error **errp) }; /* Add the rule */ + qemu_mutex_lock(&s->lock); QLIST_INSERT_HEAD(&s->rules[event], rule, next); + qemu_mutex_unlock(&s->lock); return 0; } +/* Called with lock held or from .bdrv_close */ static void remove_rule(BlkdebugRule *rule) { switch (rule->action) { @@ -467,6 +479,7 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags, int ret; uint64_t align; + qemu_mutex_init(&s->lock); opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); if (!qemu_opts_absorb_qdict(opts, options, errp)) { ret = -EINVAL; @@ -567,6 +580,7 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags, ret = 0; out: if (ret < 0) { + qemu_mutex_destroy(&s->lock); g_free(s->config_file); } qemu_opts_del(opts); @@ -581,6 +595,7 @@ static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes, int error; bool immediately; + qemu_mutex_lock(&s->lock); QSIMPLEQ_FOREACH(rule, &s->active_rules, active_next) { uint64_t inject_offset = rule->options.inject.offset; @@ -594,6 +609,7 @@ static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes, } if (!rule || !rule->options.inject.error) { + qemu_mutex_unlock(&s->lock); return 0; } @@ -605,6 +621,7 @@ static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes, remove_rule(rule); } + qemu_mutex_unlock(&s->lock); if (!immediately) { aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self()); qemu_coroutine_yield(); @@ -770,8 +787,10 @@ static void blkdebug_close(BlockDriverState *bs) } g_free(s->config_file); + qemu_mutex_destroy(&s->lock); } +/* Called with lock held. */ static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule) { BDRVBlkdebugState *s = bs->opaque; @@ -790,6 +809,7 @@ static void suspend_request(BlockDriverState *bs, BlkdebugRule *rule) } } +/* Called with lock held. */ static void process_rule(BlockDriverState *bs, struct BlkdebugRule *rule, int *action_count, int *new_state) { @@ -829,11 +849,13 @@ static void blkdebug_debug_event(BlockDriverState *bs, BlkdebugEvent event) assert((int)event >= 0 && event < BLKDBG__MAX); - new_state = s->state; - QLIST_FOREACH_SAFE(rule, &s->rules[event], next, next) { - process_rule(bs, rule, actions_count, &new_state); + WITH_QEMU_LOCK_GUARD(&s->lock) { + new_state = s->state; + QLIST_FOREACH_SAFE(rule, &s->rules[event], next, next) { + process_rule(bs, rule, actions_count, &new_state); + } + s->state = new_state; } - s->state = new_state; while (actions_count[ACTION_SUSPEND] > 0) { qemu_coroutine_yield(); @@ -861,11 +883,14 @@ static int blkdebug_debug_breakpoint(BlockDriverState *bs, const char *event, .options.suspend.tag = g_strdup(tag), }; + qemu_mutex_lock(&s->lock); QLIST_INSERT_HEAD(&s->rules[blkdebug_event], rule, next); + qemu_mutex_unlock(&s->lock); return 0; } +/* Called with lock held. May temporarily release lock. */ static int resume_req_by_tag(BDRVBlkdebugState *s, const char *tag, bool all) { BlkdebugSuspendedReq *r; @@ -888,7 +913,9 @@ retry: g_free(r->tag); g_free(r); + qemu_mutex_unlock(&s->lock); qemu_coroutine_enter(co); + qemu_mutex_lock(&s->lock); if (all) { goto retry; @@ -902,7 +929,7 @@ retry: static int blkdebug_debug_resume(BlockDriverState *bs, const char *tag) { BDRVBlkdebugState *s = bs->opaque; - + QEMU_LOCK_GUARD(&s->lock); return resume_req_by_tag(s, tag, false); } @@ -913,6 +940,7 @@ static int blkdebug_debug_remove_breakpoint(BlockDriverState *bs, BlkdebugRule *rule, *next; int i, ret = -ENOENT; + QEMU_LOCK_GUARD(&s->lock); for (i = 0; i < BLKDBG__MAX; i++) { QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) { if (rule->action == ACTION_SUSPEND && @@ -933,6 +961,7 @@ static bool blkdebug_debug_is_suspended(BlockDriverState *bs, const char *tag) BDRVBlkdebugState *s = bs->opaque; BlkdebugSuspendedReq *r; + QEMU_LOCK_GUARD(&s->lock); QLIST_FOREACH(r, &s->suspended_reqs, next) { if (!strcmp(r->tag, tag)) { return true;