From patchwork Wed Dec 11 23:04:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Tatianin X-Patchwork-Id: 13904361 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 65D3DE77180 for ; Wed, 11 Dec 2024 23:06:26 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tLVlN-0003ac-8w; Wed, 11 Dec 2024 18:05:01 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlH-0003Se-JU for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:04:57 -0500 Received: from forwardcorp1a.mail.yandex.net ([178.154.239.72]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlF-0002M9-DQ for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:04:55 -0500 Received: from mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net [IPv6:2a02:6b8:c1f:5829:0:640:f281:0]) by forwardcorp1a.mail.yandex.net (Yandex) with ESMTPS id 17FC461469; Thu, 12 Dec 2024 02:04:51 +0300 (MSK) Received: from d-tatianin-lin.yandex-team.ru (unknown [2a02:6b8:b081:1227::1:8]) by mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id b4xnrS4GamI0-IWDYxWwA; Thu, 12 Dec 2024 02:04:50 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1733958290; bh=7GZCvWgBz83cLwycZqDRu6o5tDHlLyTyQSPwIy527ac=; h=Message-Id:Date:In-Reply-To:Cc:Subject:References:To:From; b=0CG20qFKFz7eryJxG4hCHg2Jzp3/6HcwQf1IumEz4bunrGxwZWL2HiaCxtEnEp+oV BMWMI2/SmGdT5bVjESC1wGcp2AtSRhwEzuBjedk4osOslsaMNo9heQ/V8ziIBhIV8k 1sjmixfD2VEdVc3D0Q2I/0MGIfL4U8W0tJsDMCPE= Authentication-Results: mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Daniil Tatianin To: Paolo Bonzini Cc: Daniil Tatianin , Stefan Weil , Peter Xu , Fabiano Rosas , qemu-devel@nongnu.org, Vladimir Sementsov-Ogievskiy Subject: [PATCH v3 1/4] os: add an ability to lock memory on_fault Date: Thu, 12 Dec 2024 02:04:30 +0300 Message-Id: <20241211230433.1371327-2-d-tatianin@yandex-team.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> References: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=178.154.239.72; envelope-from=d-tatianin@yandex-team.ru; helo=forwardcorp1a.mail.yandex.net X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This will be used in the following commits to make it possible to only lock memory on fault instead of right away. Reviewed-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Peter Xu Signed-off-by: Daniil Tatianin --- include/sysemu/os-posix.h | 2 +- include/sysemu/os-win32.h | 3 ++- migration/postcopy-ram.c | 2 +- os-posix.c | 10 ++++++++-- system/vl.c | 2 +- 5 files changed, 13 insertions(+), 6 deletions(-) diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h index b881ac6c6f..ce5b3bccf8 100644 --- a/include/sysemu/os-posix.h +++ b/include/sysemu/os-posix.h @@ -53,7 +53,7 @@ bool os_set_runas(const char *user_id); void os_set_chroot(const char *path); void os_setup_limits(void); void os_setup_post(void); -int os_mlock(void); +int os_mlock(bool on_fault); /** * qemu_alloc_stack: diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h index b82a5d3ad9..cd61d69e10 100644 --- a/include/sysemu/os-win32.h +++ b/include/sysemu/os-win32.h @@ -123,8 +123,9 @@ static inline bool is_daemonized(void) return false; } -static inline int os_mlock(void) +static inline int os_mlock(bool on_fault) { + (void)on_fault; return -ENOSYS; } diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index a535fd2e30..36ec6a3d75 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -652,7 +652,7 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) } if (enable_mlock) { - if (os_mlock() < 0) { + if (os_mlock(false) < 0) { error_report("mlock: %s", strerror(errno)); /* * It doesn't feel right to fail at this point, we have a valid diff --git a/os-posix.c b/os-posix.c index 43f9a43f3f..0948128134 100644 --- a/os-posix.c +++ b/os-posix.c @@ -327,18 +327,24 @@ void os_set_line_buffering(void) setvbuf(stdout, NULL, _IOLBF, 0); } -int os_mlock(void) +int os_mlock(bool on_fault) { #ifdef HAVE_MLOCKALL int ret = 0; + int flags = MCL_CURRENT | MCL_FUTURE; - ret = mlockall(MCL_CURRENT | MCL_FUTURE); + if (on_fault) { + flags |= MCL_ONFAULT; + } + + ret = mlockall(flags); if (ret < 0) { error_report("mlockall: %s", strerror(errno)); } return ret; #else + (void)on_fault; return -ENOSYS; #endif } diff --git a/system/vl.c b/system/vl.c index 54998fdbc7..03819a80ef 100644 --- a/system/vl.c +++ b/system/vl.c @@ -793,7 +793,7 @@ static QemuOptsList qemu_run_with_opts = { static void realtime_init(void) { if (enable_mlock) { - if (os_mlock() < 0) { + if (os_mlock(false) < 0) { error_report("locking memory failed"); exit(1); } From patchwork Wed Dec 11 23:04:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Tatianin X-Patchwork-Id: 13904365 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 8C5E3E7717D for ; Wed, 11 Dec 2024 23:06:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tLVlO-0003bZ-Gd; Wed, 11 Dec 2024 18:05:02 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlK-0003Vp-Fq for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:04:58 -0500 Received: from forwardcorp1a.mail.yandex.net ([2a02:6b8:c0e:500:1:45:d181:df01]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlI-0002OF-No for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:04:58 -0500 Received: from mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net [IPv6:2a02:6b8:c1f:5829:0:640:f281:0]) by forwardcorp1a.mail.yandex.net (Yandex) with ESMTPS id 72C2B61447; Thu, 12 Dec 2024 02:04:54 +0300 (MSK) Received: from d-tatianin-lin.yandex-team.ru (unknown [2a02:6b8:b081:1227::1:8]) by mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id b4xnrS4GamI0-7E3QJreo; Thu, 12 Dec 2024 02:04:54 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1733958294; bh=i/w5rDBnwVLOj5y9aLzNQFkTm4o3GZ3TpsdbgF93iB8=; h=Message-Id:Date:In-Reply-To:Cc:Subject:References:To:From; b=Xl/vXkbamKZdI2X5/dD8+eQqQRhglOwXIQnKJiaUKoObLR7dIL8b2bMO5ctZsNCHb 3MH8DoRR9+ZfdzT/hvFthWXin6DE1tbpllC03X7GZfbftWOcUUFle7VRbod/mmQgzT +cRZfQDqLDCLSj5zN4etGo3vlEOE9jhZQu+6THlY= Authentication-Results: mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Daniil Tatianin To: Paolo Bonzini Cc: Daniil Tatianin , Stefan Weil , Peter Xu , Fabiano Rosas , qemu-devel@nongnu.org Subject: [PATCH v3 2/4] system/vl: extract overcommit option parsing into a helper Date: Thu, 12 Dec 2024 02:04:31 +0300 Message-Id: <20241211230433.1371327-3-d-tatianin@yandex-team.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> References: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=2a02:6b8:c0e:500:1:45:d181:df01; envelope-from=d-tatianin@yandex-team.ru; helo=forwardcorp1a.mail.yandex.net X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This will be extended in the future commits, let's move it out of line right away so that it's easier to read. Signed-off-by: Daniil Tatianin --- system/vl.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/system/vl.c b/system/vl.c index 03819a80ef..f0b3ad0df7 100644 --- a/system/vl.c +++ b/system/vl.c @@ -1855,6 +1855,19 @@ static void object_option_parse(const char *str) visit_free(v); } +static void overcommit_parse(const char *str) +{ + QemuOpts *opts; + + opts = qemu_opts_parse_noisily(qemu_find_opts("overcommit"), + str, false); + if (!opts) { + exit(1); + } + enable_mlock = qemu_opt_get_bool(opts, "mem-lock", enable_mlock); + enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm); +} + /* * Very early object creation, before the sandbox options have been activated. */ @@ -3532,13 +3545,7 @@ void qemu_init(int argc, char **argv) object_option_parse(optarg); break; case QEMU_OPTION_overcommit: - opts = qemu_opts_parse_noisily(qemu_find_opts("overcommit"), - optarg, false); - if (!opts) { - exit(1); - } - enable_mlock = qemu_opt_get_bool(opts, "mem-lock", enable_mlock); - enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm); + overcommit_parse(optarg); break; case QEMU_OPTION_compat: { From patchwork Wed Dec 11 23:04:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Tatianin X-Patchwork-Id: 13904355 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id B2F05E7717D for ; Wed, 11 Dec 2024 23:05:50 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tLVlP-0003cH-CB; Wed, 11 Dec 2024 18:05:03 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlM-0003au-Nn for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:05:01 -0500 Received: from forwardcorp1a.mail.yandex.net ([2a02:6b8:c0e:500:1:45:d181:df01]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlK-0002Oc-Vb for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:05:00 -0500 Received: from mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net [IPv6:2a02:6b8:c1f:5829:0:640:f281:0]) by forwardcorp1a.mail.yandex.net (Yandex) with ESMTPS id A05E96145B; Thu, 12 Dec 2024 02:04:57 +0300 (MSK) Received: from d-tatianin-lin.yandex-team.ru (unknown [2a02:6b8:b081:1227::1:8]) by mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id b4xnrS4GamI0-aTQBHnXU; Thu, 12 Dec 2024 02:04:57 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1733958297; bh=Vid9eybyfHkBbtn2DvtJa1fgolplJfizmxOi8mOdV4s=; h=Message-Id:Date:In-Reply-To:Cc:Subject:References:To:From; b=VUaXkpQuwgitdxYTmK62r2fe/46rjucr3JbG2UgPUm+jpAKYWZcT/faFRRNxsIusT qPWYMgIjTt3hQ7X6CppdOB34UiIEyHkddz1tnrGQhnfXSTCfcBpCYVbtnrTb0J8/HW C7Pht/9qfThgX35D5XA6xtDlLVpXbP1MVDY2BPmk= Authentication-Results: mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Daniil Tatianin To: Paolo Bonzini Cc: Daniil Tatianin , Stefan Weil , Peter Xu , Fabiano Rosas , qemu-devel@nongnu.org Subject: [PATCH v3 3/4] sysemu: introduce a new MlockState enum Date: Thu, 12 Dec 2024 02:04:32 +0300 Message-Id: <20241211230433.1371327-4-d-tatianin@yandex-team.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> References: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=2a02:6b8:c0e:500:1:45:d181:df01; envelope-from=d-tatianin@yandex-team.ru; helo=forwardcorp1a.mail.yandex.net X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Replace the boolean value enable_mlock with an enum and add a helper to decide whether we should be calling os_mlock. This is a stepping stone towards introducing a new mlock mode, which will be the third possible state of this enum. Signed-off-by: Daniil Tatianin --- hw/virtio/virtio-mem.c | 2 +- include/sysemu/sysemu.h | 10 +++++++++- migration/postcopy-ram.c | 2 +- system/globals.c | 7 ++++++- system/vl.c | 9 +++++++-- 5 files changed, 24 insertions(+), 6 deletions(-) diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 80ada89551..78d27eb141 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -988,7 +988,7 @@ static void virtio_mem_device_realize(DeviceState *dev, Error **errp) return; } - if (enable_mlock) { + if (should_mlock(mlock_state)) { error_setg(errp, "Incompatible with mlock"); return; } diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index 7ec419ce13..f1c9895057 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -43,10 +43,18 @@ extern int display_opengl; extern const char *keyboard_layout; extern int old_param; extern uint8_t *boot_splash_filedata; -extern bool enable_mlock; extern bool enable_cpu_pm; extern QEMUClockType rtc_clock; +typedef enum { + MLOCK_OFF = 0, + MLOCK_ON, +} MlockState; + +bool should_mlock(MlockState); + +extern MlockState mlock_state; + #define MAX_OPTION_ROMS 16 typedef struct QEMUOptionRom { const char *name; diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index 36ec6a3d75..a6a26a9cbb 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -651,7 +651,7 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) mis->have_fault_thread = false; } - if (enable_mlock) { + if (should_mlock(mlock_state)) { if (os_mlock(false) < 0) { error_report("mlock: %s", strerror(errno)); /* diff --git a/system/globals.c b/system/globals.c index 84ce943ac9..c6452d4a0d 100644 --- a/system/globals.c +++ b/system/globals.c @@ -31,10 +31,15 @@ #include "sysemu/cpus.h" #include "sysemu/sysemu.h" +bool should_mlock(MlockState state) +{ + return state == MLOCK_ON; +} + enum vga_retrace_method vga_retrace_method = VGA_RETRACE_DUMB; int display_opengl; const char* keyboard_layout; -bool enable_mlock; +MlockState mlock_state; bool enable_cpu_pm; int autostart = 1; int vga_interface_type = VGA_NONE; diff --git a/system/vl.c b/system/vl.c index f0b3ad0df7..a41306ac84 100644 --- a/system/vl.c +++ b/system/vl.c @@ -792,7 +792,7 @@ static QemuOptsList qemu_run_with_opts = { static void realtime_init(void) { - if (enable_mlock) { + if (should_mlock(mlock_state)) { if (os_mlock(false) < 0) { error_report("locking memory failed"); exit(1); @@ -1858,13 +1858,18 @@ static void object_option_parse(const char *str) static void overcommit_parse(const char *str) { QemuOpts *opts; + bool enable_mlock; opts = qemu_opts_parse_noisily(qemu_find_opts("overcommit"), str, false); if (!opts) { exit(1); } - enable_mlock = qemu_opt_get_bool(opts, "mem-lock", enable_mlock); + + enable_mlock = qemu_opt_get_bool(opts, "mem-lock", + should_mlock(mlock_state)); + mlock_state = enable_mlock ? MLOCK_ON : MLOCK_OFF; + enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm); } From patchwork Wed Dec 11 23:04:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Tatianin X-Patchwork-Id: 13904357 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 14DFCE7717D for ; Wed, 11 Dec 2024 23:05:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tLVlR-0003gb-78; Wed, 11 Dec 2024 18:05:05 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlP-0003cK-DV for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:05:03 -0500 Received: from forwardcorp1a.mail.yandex.net ([2a02:6b8:c0e:500:1:45:d181:df01]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tLVlN-0002PE-FV for qemu-devel@nongnu.org; Wed, 11 Dec 2024 18:05:03 -0500 Received: from mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net [IPv6:2a02:6b8:c1f:5829:0:640:f281:0]) by forwardcorp1a.mail.yandex.net (Yandex) with ESMTPS id 09BA461469; Thu, 12 Dec 2024 02:05:00 +0300 (MSK) Received: from d-tatianin-lin.yandex-team.ru (unknown [2a02:6b8:b081:1227::1:8]) by mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id b4xnrS4GamI0-SfRKyy5U; Thu, 12 Dec 2024 02:04:59 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1733958299; bh=iXA0q1LrDfFbZ3l1Q1sy8O/HmyRUyKkBL+GNkwDF21I=; h=Message-Id:Date:In-Reply-To:Cc:Subject:References:To:From; b=bzjF60smxb20INGXB61lPQoGcXMyCYvh5WzEfhNS004S5zBIADPCgK+0NAp1ntc57 3zAjRnHXNCzgUoBvp0IqvI5FJWiUYc+uMljqcRfdXYr5vm9rKZgNCDLj6aPQngraCi +oNUH1+Widjn6tlbtq7r74q/WfE6kIpDyskyvL8I= Authentication-Results: mail-nwsmtp-smtp-corp-main-83.vla.yp-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Daniil Tatianin To: Paolo Bonzini Cc: Daniil Tatianin , Stefan Weil , Peter Xu , Fabiano Rosas , qemu-devel@nongnu.org Subject: [PATCH v3 4/4] overcommit: introduce mem-lock=on-fault Date: Thu, 12 Dec 2024 02:04:33 +0300 Message-Id: <20241211230433.1371327-5-d-tatianin@yandex-team.ru> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> References: <20241211230433.1371327-1-d-tatianin@yandex-team.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=2a02:6b8:c0e:500:1:45:d181:df01; envelope-from=d-tatianin@yandex-team.ru; helo=forwardcorp1a.mail.yandex.net X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Locking the memory without MCL_ONFAULT instantly prefaults any mmaped anonymous memory with a write-fault, which introduces a lot of extra overhead in terms of memory usage when all you want to do is to prevent kcompactd from migrating and compacting QEMU pages. Add an option to only lock pages lazily as they're faulted by the process by using MCL_ONFAULT if asked. Signed-off-by: Daniil Tatianin --- include/sysemu/sysemu.h | 2 ++ migration/postcopy-ram.c | 2 +- qemu-options.hx | 14 +++++++++----- system/globals.c | 7 ++++++- system/vl.c | 34 +++++++++++++++++++++++++++------- 5 files changed, 45 insertions(+), 14 deletions(-) diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index f1c9895057..9834038e8a 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -49,9 +49,11 @@ extern QEMUClockType rtc_clock; typedef enum { MLOCK_OFF = 0, MLOCK_ON, + MLOCK_ON_FAULT, } MlockState; bool should_mlock(MlockState); +bool is_mlock_on_fault(MlockState); extern MlockState mlock_state; diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index a6a26a9cbb..fe396b8ff3 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -652,7 +652,7 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) } if (should_mlock(mlock_state)) { - if (os_mlock(false) < 0) { + if (os_mlock(is_mlock_on_fault(mlock_state)) < 0) { error_report("mlock: %s", strerror(errno)); /* * It doesn't feel right to fail at this point, we have a valid diff --git a/qemu-options.hx b/qemu-options.hx index dacc9790a4..6c8360e62e 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4566,21 +4566,25 @@ SRST ERST DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, - "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" + "-overcommit [mem-lock=on|off|on-fault][cpu-pm=on|off]\n" " run qemu with overcommit hints\n" - " mem-lock=on|off controls memory lock support (default: off)\n" + " mem-lock=on|off|on-fault controls memory lock support (default: off)\n" " cpu-pm=on|off controls cpu power management (default: off)\n", QEMU_ARCH_ALL) SRST -``-overcommit mem-lock=on|off`` +``-overcommit mem-lock=on|off|on-fault`` \ ``-overcommit cpu-pm=on|off`` Run qemu with hints about host resource overcommit. The default is to assume that host overcommits all resources. Locking qemu and guest memory can be enabled via ``mem-lock=on`` - (disabled by default). This works when host memory is not - overcommitted and reduces the worst-case latency for guest. + or ``mem-lock=on-fault`` (disabled by default). This works when + host memory is not overcommitted and reduces the worst-case latency for + guest. The on-fault option is better for reducing the memory footprint + since it makes allocations lazy, but the pages still get locked in place + once faulted by the guest or QEMU. Note that the two options are mutually + exclusive. Guest ability to manage power state of host cpus (increasing latency for other processes on the same host cpu, but decreasing latency for diff --git a/system/globals.c b/system/globals.c index c6452d4a0d..e04d6f57ec 100644 --- a/system/globals.c +++ b/system/globals.c @@ -33,7 +33,12 @@ bool should_mlock(MlockState state) { - return state == MLOCK_ON; + return state == MLOCK_ON || state == MLOCK_ON_FAULT; +} + +bool is_mlock_on_fault(MlockState state) +{ + return state == MLOCK_ON_FAULT; } enum vga_retrace_method vga_retrace_method = VGA_RETRACE_DUMB; diff --git a/system/vl.c b/system/vl.c index a41306ac84..b1fdb71a9e 100644 --- a/system/vl.c +++ b/system/vl.c @@ -347,7 +347,7 @@ static QemuOptsList qemu_overcommit_opts = { .desc = { { .name = "mem-lock", - .type = QEMU_OPT_BOOL, + .type = QEMU_OPT_STRING, }, { .name = "cpu-pm", @@ -793,7 +793,7 @@ static QemuOptsList qemu_run_with_opts = { static void realtime_init(void) { if (should_mlock(mlock_state)) { - if (os_mlock(false) < 0) { + if (os_mlock(is_mlock_on_fault(mlock_state)) < 0) { error_report("locking memory failed"); exit(1); } @@ -1858,7 +1858,7 @@ static void object_option_parse(const char *str) static void overcommit_parse(const char *str) { QemuOpts *opts; - bool enable_mlock; + const char *mem_lock_opt; opts = qemu_opts_parse_noisily(qemu_find_opts("overcommit"), str, false); @@ -1866,11 +1866,31 @@ static void overcommit_parse(const char *str) exit(1); } - enable_mlock = qemu_opt_get_bool(opts, "mem-lock", - should_mlock(mlock_state)); - mlock_state = enable_mlock ? MLOCK_ON : MLOCK_OFF; - enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm); + + mem_lock_opt = qemu_opt_get(opts, "mem-lock"); + if (!mem_lock_opt) { + return; + } + + if (strcmp(mem_lock_opt, "on") == 0) { + mlock_state = MLOCK_ON; + return; + } + + if (strcmp(mem_lock_opt, "off") == 0) { + mlock_state = MLOCK_OFF; + return; + } + + if (strcmp(mem_lock_opt, "on-fault") == 0) { + mlock_state = MLOCK_ON_FAULT; + return; + } + + error_report("parameter 'mem-lock' expects one of " + "'on', 'off', 'on-fault'"); + exit(1); } /*