From patchwork Fri Jun 26 10:19:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279338 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 623F7C433DF for ; Fri, 26 Jun 2020 13:47:53 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 3551E20679 for ; Fri, 26 Jun 2020 13:47:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3551E20679 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47102 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1joohs-0005T6-Ge for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:47:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38112) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolSj-00086H-HY for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:01 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59354) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolSh-00009B-Af for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:01 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 7DDC94089EEF; Fri, 26 Jun 2020 10:19:57 +0000 (UTC) Subject: [PATCH 03/13] migration: introduce icount field for snapshots From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:19:57 +0300 Message-ID: <159316679721.10508.17702224865978496006.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk Saving icount as a parameters of the snapshot allows navigation between them in the execution replay scenario. This information can be used for finding a specific snapshot for proceeding the recorded execution to the specific moment of the time. E.g., 'reverse step' action (introduced in one of the following patches) needs to load the nearest snapshot which is prior to the current moment of time. Signed-off-by: Pavel Dovgalyuk Acked-by: Markus Armbruster Acked-by: Kevin Wolf --- 0 files changed diff --git a/block/qapi.c b/block/qapi.c index afd9f3b4a7..3c73db54c4 100644 --- a/block/qapi.c +++ b/block/qapi.c @@ -226,6 +226,8 @@ int bdrv_query_snapshot_info_list(BlockDriverState *bs, info->date_nsec = sn_tab[i].date_nsec; info->vm_clock_sec = sn_tab[i].vm_clock_nsec / 1000000000; info->vm_clock_nsec = sn_tab[i].vm_clock_nsec % 1000000000; + info->icount = sn_tab[i].icount; + info->has_icount = sn_tab[i].icount != -1ULL; info_list = g_new0(SnapshotInfoList, 1); info_list->value = info; @@ -658,14 +660,15 @@ BlockStatsList *qmp_query_blockstats(bool has_query_nodes, void bdrv_snapshot_dump(QEMUSnapshotInfo *sn) { char date_buf[128], clock_buf[128]; + char icount_buf[128] = {0}; struct tm tm; time_t ti; int64_t secs; char *sizing = NULL; if (!sn) { - qemu_printf("%-10s%-20s%11s%20s%15s", - "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK"); + qemu_printf("%-10s%-18s%7s%20s%13s%11s", + "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK", "ICOUNT"); } else { ti = sn->date_sec; localtime_r(&ti, &tm); @@ -679,11 +682,16 @@ void bdrv_snapshot_dump(QEMUSnapshotInfo *sn) (int)(secs % 60), (int)((sn->vm_clock_nsec / 1000000) % 1000)); sizing = size_to_str(sn->vm_state_size); - qemu_printf("%-10s%-20s%11s%20s%15s", + if (sn->icount != -1ULL) { + snprintf(icount_buf, sizeof(icount_buf), + "%"PRId64, sn->icount); + } + qemu_printf("%-10s%-18s%7s%20s%13s%11s", sn->id_str, sn->name, sizing, date_buf, - clock_buf); + clock_buf, + icount_buf); } g_free(sizing); } @@ -845,6 +853,8 @@ void bdrv_image_info_dump(ImageInfo *info) .date_nsec = elem->value->date_nsec, .vm_clock_nsec = elem->value->vm_clock_sec * 1000000000ULL + elem->value->vm_clock_nsec, + .icount = elem->value->has_icount ? + elem->value->icount : -1ULL, }; pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id); diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index d14e7be1aa..4b127ea6af 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -663,6 +663,7 @@ int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info) sn->date_sec = sn_info->date_sec; sn->date_nsec = sn_info->date_nsec; sn->vm_clock_nsec = sn_info->vm_clock_nsec; + sn->icount = sn_info->icount; sn->extra_data_size = sizeof(QCowSnapshotExtraData); /* Allocate the L1 table of the snapshot and copy the current one there. */ @@ -1007,6 +1008,7 @@ int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab) sn_info->date_sec = sn->date_sec; sn_info->date_nsec = sn->date_nsec; sn_info->vm_clock_nsec = sn->vm_clock_nsec; + sn_info->icount = sn->icount; } *psn_tab = sn_tab; return s->nb_snapshots; diff --git a/blockdev.c b/blockdev.c index 31d5eaf6bf..50496700af 100644 --- a/blockdev.c +++ b/blockdev.c @@ -59,6 +59,7 @@ #include "sysemu/arch_init.h" #include "sysemu/qtest.h" #include "sysemu/runstate.h" +#include "sysemu/replay.h" #include "qemu/cutils.h" #include "qemu/help_option.h" #include "qemu/main-loop.h" @@ -1200,6 +1201,10 @@ SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device, info->vm_state_size = sn.vm_state_size; info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000; info->vm_clock_sec = sn.vm_clock_nsec / 1000000000; + if (sn.icount != -1ULL) { + info->icount = sn.icount; + info->has_icount = true; + } return info; @@ -1360,6 +1365,11 @@ static void internal_snapshot_prepare(BlkActionState *common, sn->date_sec = tv.tv_sec; sn->date_nsec = tv.tv_usec * 1000; sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + if (replay_mode != REPLAY_MODE_NONE) { + sn->icount = replay_get_current_icount(); + } else { + sn->icount = -1ULL; + } ret1 = bdrv_snapshot_create(bs, sn); if (ret1 < 0) { diff --git a/include/block/snapshot.h b/include/block/snapshot.h index 2bfcd57578..b0fe42993d 100644 --- a/include/block/snapshot.h +++ b/include/block/snapshot.h @@ -42,6 +42,7 @@ typedef struct QEMUSnapshotInfo { uint32_t date_sec; /* UTC date of the snapshot */ uint32_t date_nsec; uint64_t vm_clock_nsec; /* VM clock relative to boot */ + uint64_t icount; /* record/replay step */ } QEMUSnapshotInfo; int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info, diff --git a/migration/savevm.c b/migration/savevm.c index b979ea6e7f..f583b9bd08 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -2689,6 +2689,11 @@ int save_snapshot(const char *name, Error **errp) sn->date_sec = tv.tv_sec; sn->date_nsec = tv.tv_usec * 1000; sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + if (replay_mode != REPLAY_MODE_NONE) { + sn->icount = replay_get_current_icount(); + } else { + sn->icount = -1ULL; + } if (name) { ret = bdrv_snapshot_find(bs, old_sn, name); diff --git a/qapi/block-core.json b/qapi/block-core.json index 0e1c6a59f2..125ef7b1c2 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -26,13 +26,18 @@ # # @vm-clock-nsec: fractional part in nano seconds to be used with vm-clock-sec # +# @icount: Current instruction count. Appears when execution record/replay +# is enabled. Used for "time-traveling" to match the moment +# in the recorded execution with the snapshots. (since 5.1) +# # Since: 1.3 # ## { 'struct': 'SnapshotInfo', 'data': { 'id': 'str', 'name': 'str', 'vm-state-size': 'int', 'date-sec': 'int', 'date-nsec': 'int', - 'vm-clock-sec': 'int', 'vm-clock-nsec': 'int' } } + 'vm-clock-sec': 'int', 'vm-clock-nsec': 'int', + '*icount': 'int' } } ## # @ImageInfoSpecificQCow2EncryptionBase: @@ -5458,7 +5463,8 @@ # "date-sec": 1000012, # "date-nsec": 10, # "vm-clock-sec": 100, -# "vm-clock-nsec": 20 +# "vm-clock-nsec": 20, +# "icount": 220414 # } # } # diff --git a/stubs/replay.c b/stubs/replay.c index 5974ec1f50..eacb366aa8 100644 --- a/stubs/replay.c +++ b/stubs/replay.c @@ -88,3 +88,8 @@ int replay_read_random(void *buf, size_t len) { return 0; } + +uint64_t replay_get_current_icount(void) +{ + return 0; +} From patchwork Fri Jun 26 10:20:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279337 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7CB8C433E0 for ; Fri, 26 Jun 2020 13:49:24 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 8E64820656 for ; Fri, 26 Jun 2020 13:49:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E64820656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:51264 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1joojL-0007FH-SM for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:49:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38166) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolSo-0008Bh-Sx for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:06 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59376) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolSn-0000AU-0e for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:06 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 2DF9A4089EF0; Fri, 26 Jun 2020 10:20:03 +0000 (UTC) Subject: [PATCH 04/13] iotests: update snapshot test for new output format From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:02 +0300 Message-ID: <159316680291.10508.18200905213455758659.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk This patch updates iotests that verify qemu monitor output. New output format for snapshot listing include ICOUNT column. Signed-off-by: Pavel Dovgalyuk --- 0 files changed diff --git a/tests/qemu-iotests/267.out b/tests/qemu-iotests/267.out index 8dddb4baa4..c4f3d8dd33 100644 --- a/tests/qemu-iotests/267.out +++ b/tests/qemu-iotests/267.out @@ -33,8 +33,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -44,8 +44,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -69,8 +69,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -94,8 +94,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -105,8 +105,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -119,8 +119,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -134,8 +134,8 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit @@ -145,15 +145,15 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit Internal snapshots on overlay: Snapshot list: -ID TAG VM SIZE DATE VM CLOCK -1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 Internal snapshots on backing file: === -blockdev with NBD server on the backing file === @@ -166,17 +166,17 @@ QEMU X.Y.Z monitor - type 'help' for more information (qemu) savevm snap0 (qemu) info snapshots List of snapshots present on all disks: -ID TAG VM SIZE DATE VM CLOCK --- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +-- snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 (qemu) loadvm snap0 (qemu) quit Internal snapshots on overlay: Snapshot list: -ID TAG VM SIZE DATE VM CLOCK -1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 Internal snapshots on backing file: Snapshot list: -ID TAG VM SIZE DATE VM CLOCK -1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 +ID TAG VM SIZE DATE VM CLOCK ICOUNT +1 snap0 SIZE yyyy-mm-dd hh:mm:ss 00:00:00.000 *** done From patchwork Fri Jun 26 10:20:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279342 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 293E4C433DF for ; Fri, 26 Jun 2020 13:43:17 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id F0F7320656 for ; Fri, 26 Jun 2020 13:43:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F0F7320656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54028 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1joodQ-00057J-7N for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:43:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38284) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolT0-0008NS-8p for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:18 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59416) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolSy-0000Fh-D1 for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:17 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 89AFB4089EF2; Fri, 26 Jun 2020 10:20:14 +0000 (UTC) Subject: [PATCH 06/13] replay: introduce info hmp/qmp command From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:14 +0300 Message-ID: <159316681429.10508.4981399825825703105.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk This patch introduces 'info replay' monitor command and corresponding qmp request. These commands request the current record/replay mode, replay log file name, and the instruction count (number of recorded/replayed instructions). The instruction count can be used with the replay_seek/replay_break commands added in the next two patches. Signed-off-by: Pavel Dovgalyuk Acked-by: Dr. David Alan Gilbert Acked-by: Markus Armbruster --- 0 files changed diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx index 30209e3903..117ba25f91 100644 --- a/hmp-commands-info.hx +++ b/hmp-commands-info.hx @@ -881,4 +881,15 @@ SRST Show SEV information. ERST + { + .name = "replay", + .args_type = "", + .params = "", + .help = "show record/replay information", + .cmd = hmp_info_replay, + }, +SRST + ``info replay`` + Display the record/replay information: mode and the current icount. +ERST diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h index c986cfd28b..a790589b9e 100644 --- a/include/monitor/hmp.h +++ b/include/monitor/hmp.h @@ -130,5 +130,6 @@ void hmp_hotpluggable_cpus(Monitor *mon, const QDict *qdict); void hmp_info_vm_generation_id(Monitor *mon, const QDict *qdict); void hmp_info_memory_size_summary(Monitor *mon, const QDict *qdict); void hmp_info_sev(Monitor *mon, const QDict *qdict); +void hmp_info_replay(Monitor *mon, const QDict *qdict); #endif diff --git a/qapi/block-core.json b/qapi/block-core.json index 125ef7b1c2..947ef00a96 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -28,7 +28,8 @@ # # @icount: Current instruction count. Appears when execution record/replay # is enabled. Used for "time-traveling" to match the moment -# in the recorded execution with the snapshots. (since 5.1) +# in the recorded execution with the snapshots. This counter may +# be obtained through @query-replay command (since 5.1) # # Since: 1.3 # diff --git a/qapi/replay.json b/qapi/replay.json index 9e13551d20..0a160466f2 100644 --- a/qapi/replay.json +++ b/qapi/replay.json @@ -24,3 +24,42 @@ ## { 'enum': 'ReplayMode', 'data': [ 'none', 'record', 'play' ] } + +## +# @ReplayInfo: +# +# Record/replay information. +# +# @mode: current mode. +# +# @filename: name of the record/replay log file. +# It is present only in record or replay modes, when the log +# is recorded or replayed. +# +# @icount: current number of executed instructions. +# +# Since: 5.1 +# +## +{ 'struct': 'ReplayInfo', + 'data': { 'mode': 'ReplayMode', '*filename': 'str', 'icount': 'int' } } + +## +# @query-replay: +# +# Retrieve the record/replay information. +# It includes current instruction count which may be used for +# @replay-break and @replay-seek commands. +# +# Returns: record/replay information. +# +# Since: 5.1 +# +# Example: +# +# -> { "execute": "query-replay" } +# <- { "return": { "mode": "play", "filename": "log.rr", "icount": 220414 } } +# +## +{ 'command': 'query-replay', + 'returns': 'ReplayInfo' } diff --git a/replay/Makefile.objs b/replay/Makefile.objs index 939be964a9..f847c5c023 100644 --- a/replay/Makefile.objs +++ b/replay/Makefile.objs @@ -8,3 +8,4 @@ common-obj-y += replay-snapshot.o common-obj-y += replay-net.o common-obj-y += replay-audio.o common-obj-y += replay-random.o +common-obj-y += replay-debugging.o diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c new file mode 100644 index 0000000000..51a6de4e81 --- /dev/null +++ b/replay/replay-debugging.c @@ -0,0 +1,43 @@ +/* + * replay-debugging.c + * + * Copyright (c) 2010-2020 Institute for System Programming + * of the Russian Academy of Sciences. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "sysemu/replay.h" +#include "replay-internal.h" +#include "monitor/hmp.h" +#include "monitor/monitor.h" +#include "qapi/qapi-commands-replay.h" + +void hmp_info_replay(Monitor *mon, const QDict *qdict) +{ + if (replay_mode == REPLAY_MODE_NONE) { + monitor_printf(mon, "Record/replay is not active\n"); + } else { + monitor_printf(mon, + "%s execution '%s': instruction count = %"PRId64"\n", + replay_mode == REPLAY_MODE_RECORD ? "Recording" : "Replaying", + replay_get_filename(), replay_get_current_icount()); + } +} + +ReplayInfo *qmp_query_replay(Error **errp) +{ + ReplayInfo *retval = g_new0(ReplayInfo, 1); + + retval->mode = replay_mode; + if (replay_get_filename()) { + retval->filename = g_strdup(replay_get_filename()); + retval->has_filename = true; + } + retval->icount = replay_get_current_icount(); + return retval; +} From patchwork Fri Jun 26 10:20:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279340 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02863C433E0 for ; Fri, 26 Jun 2020 13:44:54 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id C68F220679 for ; Fri, 26 Jun 2020 13:44:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C68F220679 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34388 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jooez-0000CH-0O for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:44:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38312) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolT6-0008Uh-7A for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:24 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59434) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolT4-0000Lp-4K for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:23 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 437774089EF4; Fri, 26 Jun 2020 10:20:20 +0000 (UTC) Subject: [PATCH 07/13] replay: introduce breakpoint at the specified step From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:20 +0300 Message-ID: <159316681996.10508.1440640483514730623.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk This patch introduces replay_break, replay_delete_break qmp and hmp commands. These commands allow stopping at the specified instruction. It may be useful for debugging when there are some known events that should be investigated. replay_break command has one argument - number of instructions executed since the start of the replay. replay_delete_break removes previously set breakpoint. Signed-off-by: Pavel Dovgalyuk Acked-by: Markus Armbruster --- 0 files changed diff --git a/hmp-commands.hx b/hmp-commands.hx index 60f395c276..e8ce385879 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1819,6 +1819,38 @@ SRST Set QOM property *property* of object at location *path* to value *value* ERST + { + .name = "replay_break", + .args_type = "icount:i", + .params = "icount", + .help = "set breakpoint at the specified instruction count", + .cmd = hmp_replay_break, + }, + +SRST +``replay_break`` *icount* + Set replay breakpoint at instruction count *icount*. + Execution stops when the specified instruction is reached. + There can be at most one breakpoint. When breakpoint is set, any prior + one is removed. The breakpoint may be set only in replay mode and only + "in the future", i.e. at instruction counts greater than the current one. + The current instruction count can be observed with ``info replay``. +ERST + + { + .name = "replay_delete_break", + .args_type = "", + .params = "", + .help = "remove replay breakpoint", + .cmd = hmp_replay_delete_break, + }, + +SRST +``replay_delete_break`` + Remove replay breakpoint which was previously set with ``replay_break``. + The command is ignored when there are no replay breakpoints. +ERST + { .name = "info", .args_type = "item:s?", diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h index a790589b9e..21849bdda5 100644 --- a/include/monitor/hmp.h +++ b/include/monitor/hmp.h @@ -131,5 +131,7 @@ void hmp_info_vm_generation_id(Monitor *mon, const QDict *qdict); void hmp_info_memory_size_summary(Monitor *mon, const QDict *qdict); void hmp_info_sev(Monitor *mon, const QDict *qdict); void hmp_info_replay(Monitor *mon, const QDict *qdict); +void hmp_replay_break(Monitor *mon, const QDict *qdict); +void hmp_replay_delete_break(Monitor *mon, const QDict *qdict); #endif diff --git a/qapi/replay.json b/qapi/replay.json index 0a160466f2..edf7cc9265 100644 --- a/qapi/replay.json +++ b/qapi/replay.json @@ -63,3 +63,39 @@ ## { 'command': 'query-replay', 'returns': 'ReplayInfo' } + +## +# @replay-break: +# +# Set replay breakpoint at instruction count @icount. +# Execution stops when the specified instruction is reached. +# There can be at most one breakpoint. When breakpoint is set, any prior +# one is removed. The breakpoint may be set only in replay mode and only +# "in the future", i.e. at instruction counts greater than the current one. +# The current instruction count can be observed with @query-replay. +# +# @icount: instruction count to stop at +# +# Since: 5.1 +# +# Example: +# +# -> { "execute": "replay-break", "data": { "icount": 220414 } } +# +## +{ 'command': 'replay-break', 'data': { 'icount': 'int' } } + +## +# @replay-delete-break: +# +# Remove replay breakpoint which was set with @replay-break. +# The command is ignored when there are no replay breakpoints. +# +# Since: 5.1 +# +# Example: +# +# -> { "execute": "replay-delete-break" } +# +## +{ 'command': 'replay-delete-break' } diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c index 51a6de4e81..86e19bb217 100644 --- a/replay/replay-debugging.c +++ b/replay/replay-debugging.c @@ -12,10 +12,13 @@ #include "qemu/osdep.h" #include "qapi/error.h" #include "sysemu/replay.h" +#include "sysemu/runstate.h" #include "replay-internal.h" #include "monitor/hmp.h" #include "monitor/monitor.h" #include "qapi/qapi-commands-replay.h" +#include "qapi/qmp/qdict.h" +#include "qemu/timer.h" void hmp_info_replay(Monitor *mon, const QDict *qdict) { @@ -41,3 +44,86 @@ ReplayInfo *qmp_query_replay(Error **errp) retval->icount = replay_get_current_icount(); return retval; } + +static void replay_break(uint64_t icount, QEMUTimerCB callback, void *opaque) +{ + assert(replay_mode == REPLAY_MODE_PLAY); + assert(replay_mutex_locked()); + assert(replay_break_icount >= replay_get_current_icount()); + assert(callback); + + replay_break_icount = icount; + + if (replay_break_timer) { + timer_del(replay_break_timer); + } + replay_break_timer = timer_new_ns(QEMU_CLOCK_REALTIME, + callback, opaque); +} + +static void replay_delete_break(void) +{ + assert(replay_mode == REPLAY_MODE_PLAY); + assert(replay_mutex_locked()); + + if (replay_break_timer) { + timer_del(replay_break_timer); + timer_free(replay_break_timer); + replay_break_timer = NULL; + } + replay_break_icount = -1ULL; +} + +static void replay_stop_vm(void *opaque) +{ + vm_stop(RUN_STATE_PAUSED); + replay_delete_break(); +} + +void qmp_replay_break(int64_t icount, Error **errp) +{ + if (replay_mode == REPLAY_MODE_PLAY) { + if (icount >= replay_get_current_icount()) { + replay_break(icount, replay_stop_vm, NULL); + } else { + error_setg(errp, + "cannot set breakpoint at the instruction in the past"); + } + } else { + error_setg(errp, "setting the breakpoint is allowed only in play mode"); + } +} + +void hmp_replay_break(Monitor *mon, const QDict *qdict) +{ + int64_t icount = qdict_get_try_int(qdict, "icount", -1LL); + Error *err = NULL; + + qmp_replay_break(icount, &err); + if (err) { + error_report_err(err); + error_free(err); + return; + } +} + +void qmp_replay_delete_break(Error **errp) +{ + if (replay_mode == REPLAY_MODE_PLAY) { + replay_delete_break(); + } else { + error_setg(errp, "replay breakpoints are allowed only in play mode"); + } +} + +void hmp_replay_delete_break(Monitor *mon, const QDict *qdict) +{ + Error *err = NULL; + + qmp_replay_delete_break(&err); + if (err) { + error_report_err(err); + error_free(err); + return; + } +} diff --git a/replay/replay-internal.h b/replay/replay-internal.h index 33ac551e78..2f6145ec7c 100644 --- a/replay/replay-internal.h +++ b/replay/replay-internal.h @@ -94,6 +94,10 @@ extern ReplayState replay_state; /* File for replay writing */ extern FILE *replay_file; +/* Instruction count of the replay breakpoint */ +extern uint64_t replay_break_icount; +/* Timer for the replay breakpoint callback */ +extern QEMUTimer *replay_break_timer; void replay_put_byte(uint8_t byte); void replay_put_event(uint8_t event); diff --git a/replay/replay.c b/replay/replay.c index 42e82f7bc7..220886e32e 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -34,6 +34,10 @@ static char *replay_filename; ReplayState replay_state; static GSList *replay_blockers; +/* Replay breakpoints */ +uint64_t replay_break_icount = -1ULL; +QEMUTimer *replay_break_timer; + bool replay_next_event_is(int event) { bool res = false; @@ -73,6 +77,13 @@ int replay_get_instructions(void) replay_mutex_lock(); if (replay_next_event_is(EVENT_INSTRUCTION)) { res = replay_state.instruction_count; + if (replay_break_icount != -1LL) { + uint64_t current = replay_get_current_icount(); + assert(replay_break_icount >= current); + if (current + res > replay_break_icount) { + res = replay_break_icount - current; + } + } } replay_mutex_unlock(); return res; @@ -99,6 +110,12 @@ void replay_account_executed_instructions(void) will be read from the log. */ qemu_notify_event(); } + /* Execution reached the break step */ + if (replay_break_icount == replay_state.current_icount) { + /* Cannot make callback directly from the vCPU thread */ + timer_mod_ns(replay_break_timer, + qemu_clock_get_ns(QEMU_CLOCK_REALTIME)); + } } } } From patchwork Fri Jun 26 10:20:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279341 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88F29C433E0 for ; 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Fri, 26 Jun 2020 06:20:34 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 9D6614089F07; Fri, 26 Jun 2020 10:20:31 +0000 (UTC) Subject: [PATCH 09/13] replay: flush rr queue before loading the vmstate From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:31 +0300 Message-ID: <159316683138.10508.3504505477148703571.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk Non-empty record/replay queue prevents saving and loading the VM state, because it includes pending bottom halves and block coroutines. But when the new VM state is loaded, we don't have to preserve the consistency of the current state anymore. Therefore this patch just flushes the queue allowing the coroutines to finish and removes checking for empty rr queue for load_snapshot function. Signed-off-by: Pavel Dovgalyuk --- 0 files changed diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index e00ed2f4a5..239c01e7df 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -149,6 +149,8 @@ void replay_disable_events(void); void replay_enable_events(void); /*! Returns true when saving events is enabled */ bool replay_events_enabled(void); +/* Flushes events queue */ +void replay_flush_events(void); /*! Adds bottom half event to the queue */ void replay_bh_schedule_event(QEMUBH *bh); /* Adds oneshot bottom half event to the queue */ diff --git a/migration/savevm.c b/migration/savevm.c index f583b9bd08..7d9d57ac33 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -2842,12 +2842,6 @@ int load_snapshot(const char *name, Error **errp) AioContext *aio_context; MigrationIncomingState *mis = migration_incoming_get_current(); - if (!replay_can_snapshot()) { - error_setg(errp, "Record/replay does not allow loading snapshot " - "right now. Try once more later."); - return -EINVAL; - } - if (!bdrv_all_can_snapshot(&bs)) { error_setg(errp, "Device '%s' is writable but does not support snapshots", @@ -2881,6 +2875,12 @@ int load_snapshot(const char *name, Error **errp) return -EINVAL; } + /* + * Flush the record/replay queue. Now the VM state is going + * to change. Therefore we don't need to preserve its consistency + */ + replay_flush_events(); + /* Flush all IO requests so they don't interfere with the new state. */ bdrv_drain_all_begin(); diff --git a/replay/replay-events.c b/replay/replay-events.c index 302b84043a..a1c6bb934e 100644 --- a/replay/replay-events.c +++ b/replay/replay-events.c @@ -77,6 +77,10 @@ bool replay_has_events(void) void replay_flush_events(void) { + if (replay_mode == REPLAY_MODE_NONE) { + return; + } + g_assert(replay_mutex_locked()); while (!QTAILQ_EMPTY(&events_list)) { diff --git a/replay/replay-internal.h b/replay/replay-internal.h index 2f6145ec7c..97649ed8d7 100644 --- a/replay/replay-internal.h +++ b/replay/replay-internal.h @@ -149,8 +149,6 @@ void replay_read_next_clock(unsigned int kind); void replay_init_events(void); /*! Clears internal data structures for events handling */ void replay_finish_events(void); -/*! Flushes events queue */ -void replay_flush_events(void); /*! Returns true if there are any unsaved events in the queue */ bool replay_has_events(void); /*! Saves events from queue into the file */ From patchwork Fri Jun 26 10:20:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279339 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55D1CC433E1 for ; Fri, 26 Jun 2020 13:46:18 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 2A2912088E for ; Fri, 26 Jun 2020 13:46:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2A2912088E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:40716 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1joogL-0002ry-9c for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:46:17 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38424) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolTN-0000N2-2d for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:41 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59494) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolTL-0000RQ-1A for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:40 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id 4E7EC4089F08; Fri, 26 Jun 2020 10:20:37 +0000 (UTC) Subject: [PATCH 10/13] gdbstub: add reverse step support in replay mode From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:37 +0300 Message-ID: <159316683702.10508.7973844299019522260.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk GDB remote protocol supports two reverse debugging commands: reverse step and reverse continue. This patch adds support of the first one to the gdbstub. Reverse step is intended to step one instruction in the backwards direction. This is not possible in regular execution. But replayed execution is deterministic, therefore we can load one of the prior snapshots and proceed to the desired step. It is equivalent to stepping one instruction back. There should be at least one snapshot preceding the debugged part of the replay log. Signed-off-by: Pavel Dovgalyuk --- 0 files changed diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c index 603d17ff83..fb1e19c585 100644 --- a/accel/tcg/translator.c +++ b/accel/tcg/translator.c @@ -17,6 +17,7 @@ #include "exec/log.h" #include "exec/translator.h" #include "exec/plugin-gen.h" +#include "sysemu/replay.h" /* Pairs with tcg_clear_temp_count. To be called by #TranslatorOps.{translate_insn,tb_stop} if diff --git a/cpus.c b/cpus.c index 41d1c5099f..35381ea941 100644 --- a/cpus.c +++ b/cpus.c @@ -1100,9 +1100,17 @@ static bool cpu_can_run(CPUState *cpu) static void cpu_handle_guest_debug(CPUState *cpu) { - gdb_set_stop_cpu(cpu); - qemu_system_debug_request(); - cpu->stopped = true; + if (!replay_running_debug()) { + gdb_set_stop_cpu(cpu); + qemu_system_debug_request(); + cpu->stopped = true; + } else { + if (!cpu->singlestep_enabled) { + cpu_single_step(cpu, SSTEP_ENABLE); + } else { + cpu_single_step(cpu, 0); + } + } } #ifdef CONFIG_LINUX diff --git a/exec.c b/exec.c index d6712fba7e..4bde79ea3b 100644 --- a/exec.c +++ b/exec.c @@ -2720,6 +2720,13 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) { if (watchpoint_address_matches(wp, addr, len) && (wp->flags & flags)) { + if (replay_running_debug()) { + /* + * Don't process the watchpoints when we are + * in a reverse debugging operation. + */ + return; + } if (flags == BP_MEM_READ) { wp->flags |= BP_WATCHPOINT_HIT_READ; } else { diff --git a/gdbstub.c b/gdbstub.c index 6950fd243f..a81b3b5fb8 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -51,6 +51,7 @@ #include "sysemu/runstate.h" #include "hw/semihosting/semihost.h" #include "exec/exec-all.h" +#include "sysemu/replay.h" #ifdef CONFIG_USER_ONLY #define GDB_ATTACHED "0" @@ -375,6 +376,20 @@ typedef struct GDBState { */ static int sstep_flags = SSTEP_ENABLE|SSTEP_NOIRQ|SSTEP_NOTIMER; +/* Retrieves flags for single step mode. */ +static int get_sstep_flags(void) +{ + /* + * In replay mode all events written into the log should be replayed. + * That is why NOIRQ flag is removed in this mode. + */ + if (replay_mode != REPLAY_MODE_NONE) { + return SSTEP_ENABLE; + } else { + return sstep_flags; + } +} + static GDBState gdbserver_state; static void init_gdbserver_state(void) @@ -501,7 +516,7 @@ static int gdb_continue_partial(char *newstates) break; /* nothing to do here */ case 's': trace_gdbstub_op_stepping(cpu->cpu_index); - cpu_single_step(cpu, sstep_flags); + cpu_single_step(cpu, get_sstep_flags()); cpu_resume(cpu); flag = 1; break; @@ -1874,10 +1889,31 @@ static void handle_step(GdbCmdContext *gdb_ctx, void *user_ctx) gdb_set_cpu_pc((target_ulong)gdb_ctx->params[0].val_ull); } - cpu_single_step(gdbserver_state.c_cpu, sstep_flags); + cpu_single_step(gdbserver_state.c_cpu, get_sstep_flags()); gdb_continue(); } +static void handle_backward(GdbCmdContext *gdb_ctx, void *user_ctx) +{ + if (replay_mode != REPLAY_MODE_PLAY) { + put_packet("E22"); + } + if (gdb_ctx->num_params == 1) { + switch (gdb_ctx->params[0].opcode) { + case 's': + if (replay_reverse_step()) { + gdb_continue(); + } else { + put_packet("E14"); + } + return; + } + } + + /* Default invalid command */ + put_packet(""); +} + static void handle_v_cont_query(GdbCmdContext *gdb_ctx, void *user_ctx) { put_packet("vCont;c;C;s;S"); @@ -2124,6 +2160,10 @@ static void handle_query_supported(GdbCmdContext *gdb_ctx, void *user_ctx) g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+"); } + if (replay_mode == REPLAY_MODE_PLAY) { + g_string_append(gdbserver_state.str_buf, ";ReverseStep+"); + } + if (gdb_ctx->num_params && strstr(gdb_ctx->params[0].data, "multiprocess+")) { gdbserver_state.multiprocess = true; @@ -2460,6 +2500,17 @@ static int gdb_handle_packet(const char *line_buf) cmd_parser = &step_cmd_desc; } break; + case 'b': + { + static const GdbCmdParseEntry backward_cmd_desc = { + .handler = handle_backward, + .cmd = "b", + .cmd_startswith = 1, + .schema = "o0" + }; + cmd_parser = &backward_cmd_desc; + } + break; case 'F': { static const GdbCmdParseEntry file_io_cmd_desc = { diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index 239c01e7df..13a8123b09 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -75,6 +75,17 @@ void replay_finish(void); void replay_add_blocker(Error *reason); /* Returns name of the replay log file */ const char *replay_get_filename(void); +/* + * Start making one step in backward direction. + * Used by gdbstub for backwards debugging. + * Returns true on success. + */ +bool replay_reverse_step(void); +/* + * Returns true if replay module is processing + * reverse_continue or reverse_step request + */ +bool replay_running_debug(void); /* Processing the instructions */ diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c index cfd0221692..aa3ca040e2 100644 --- a/replay/replay-debugging.c +++ b/replay/replay-debugging.c @@ -22,6 +22,13 @@ #include "block/snapshot.h" #include "migration/snapshot.h" +static bool replay_is_debugging; + +bool replay_running_debug(void) +{ + return replay_is_debugging; +} + void hmp_info_replay(Monitor *mon, const QDict *qdict) { if (replay_mode == REPLAY_MODE_NONE) { @@ -219,3 +226,29 @@ void hmp_replay_seek(Monitor *mon, const QDict *qdict) return; } } + +static void replay_stop_vm_debug(void *opaque) +{ + replay_is_debugging = false; + vm_stop(RUN_STATE_DEBUG); + replay_delete_break(); +} + +bool replay_reverse_step(void) +{ + Error *err = NULL; + + assert(replay_mode == REPLAY_MODE_PLAY); + + if (replay_get_current_icount() != 0) { + replay_seek(replay_get_current_icount() - 1, replay_stop_vm_debug, &err); + if (err) { + error_free(err); + return false; + } + replay_is_debugging = true; + return true; + } + + return false; +} diff --git a/stubs/replay.c b/stubs/replay.c index eacb366aa8..d5b52302e9 100644 --- a/stubs/replay.c +++ b/stubs/replay.c @@ -93,3 +93,8 @@ uint64_t replay_get_current_icount(void) { return 0; } + +bool replay_reverse_step(void) +{ + return false; +} From patchwork Fri Jun 26 10:20:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 279343 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23B08C433E1 for ; Fri, 26 Jun 2020 13:42:57 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id F1A3320656 for ; Fri, 26 Jun 2020 13:42:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1A3320656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52052 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jood6-0004J6-7p for qemu-devel@archiver.kernel.org; Fri, 26 Jun 2020 09:42:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38492) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolTY-0000Ok-26 for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:52 -0400 Received: from mail.ispras.ru ([83.149.199.84]:59562) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jolTW-0000YG-Cw for qemu-devel@nongnu.org; Fri, 26 Jun 2020 06:20:51 -0400 Received: from [127.0.1.1] (unknown [62.118.151.149]) by mail.ispras.ru (Postfix) with ESMTPSA id A3C6640A92BE; Fri, 26 Jun 2020 10:20:48 +0000 (UTC) Subject: [PATCH 12/13] replay: describe reverse debugging in docs/replay.txt From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Fri, 26 Jun 2020 13:20:48 +0300 Message-ID: <159316684833.10508.798035270216502557.stgit@pasha-ThinkPad-X280> In-Reply-To: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> References: <159316678008.10508.6615172353109944370.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.ru X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/26 06:19:41 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-Mailman-Approved-At: Fri, 26 Jun 2020 09:41:37 -0400 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: kwolf@redhat.com, wrampazz@redhat.com, pavel.dovgalyuk@ispras.ru, ehabkost@redhat.com, alex.bennee@linaro.org, mtosatti@redhat.com, armbru@redhat.com, mreitz@redhat.com, stefanha@redhat.com, crosa@redhat.com, pbonzini@redhat.com, philmd@redhat.com, zhiwei_liu@c-sky.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pavel Dovgalyuk This patch updates the documentation and describes usage of the reverse debugging in QEMU+GDB. Signed-off-by: Pavel Dovgalyuk --- 0 files changed diff --git a/docs/replay.txt b/docs/replay.txt index 70c27edb36..18d6169f3b 100644 --- a/docs/replay.txt +++ b/docs/replay.txt @@ -294,6 +294,39 @@ for recording and replaying must contain identical number of ports in record and replay modes, but their backends may differ. E.g., '-serial stdio' in record mode, and '-serial null' in replay mode. +Reverse debugging +----------------- + +Reverse debugging allows "executing" the program in reverse direction. +GDB remote protocol supports "reverse step" and "reverse continue" +commands. The first one steps single instruction backwards in time, +and the second one finds the last breakpoint in the past. + +Recorded executions may be used to enable reverse debugging. QEMU can't +execute the code in backwards direction, but can load a snapshot and +replay forward to find the desired position or breakpoint. + +The following GDB commands are supported: + - reverse-stepi (or rsi) - step one instruction backwards + - reverse-continue (or rc) - find last breakpoint in the past + +Reverse step loads the nearest snapshot and replays the execution until +the required instruction is met. + +Reverse continue may include several passes of examining the execution +between the snapshots. Each of the passes include the following steps: + 1. loading the snapshot + 2. replaying to examine the breakpoints + 3. if breakpoint or watchpoint was met + - loading the snaphot again + - replaying to the required breakpoint + 4. else + - proceeding to the p.1 with the earlier snapshot + +Therefore usage of the reverse debugging requires at least one snapshot +created in advance. See the "Snapshotting" section to learn about running +record/replay and creating the snapshot in these modes. + Replay log format -----------------