From patchwork Sat Dec 24 15:18:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Richard Henderson X-Patchwork-Id: 1719328 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.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: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=linaro.org header.i=@linaro.org header.a=rsa-sha256 header.s=google header.b=aDUfRt60; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4NfSPw6N3Xz23dk for ; Sun, 25 Dec 2022 02:19:14 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p96I9-00056t-NV; Sat, 24 Dec 2022 10:18:29 -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 1p96I7-00056H-QE for qemu-devel@nongnu.org; Sat, 24 Dec 2022 10:18:27 -0500 Received: from mail-pf1-x42c.google.com ([2607:f8b0:4864:20::42c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1p96I6-00016e-4f for qemu-devel@nongnu.org; Sat, 24 Dec 2022 10:18:27 -0500 Received: by mail-pf1-x42c.google.com with SMTP id a14so4996047pfa.1 for ; Sat, 24 Dec 2022 07:18:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=3ZdTKdjXZPsSu57R08aDOC5nHrf6U05QdlzIh/dh4Ps=; b=aDUfRt60uiyPxMbkGC3D0P9U7IT90che4HNEepZo/fMsGQAEyFZgM4EFkOOuDlV3BQ H1PJgpXz7+oUM+S17BszscIkYuFh0GqxSOD4ynhVZIvcra+4cmMzb1CY4p9qNJsMXCGx 8pk0e3hhE5YqjDOk69AewG5vTdI8WtgaKhKykEjWj2knjh89AteKA6pa6Sx52qUOxfzc SEVTKxiAocrBdsR1pgptHxPm12FRP5E9qAXe7F9BgdxrAPZmfwImYxfVsX8p8qsj3wnX zVX4b081Vmdwv8cQCl8Nwagn0yE6vQDwV+Q0z1XydaQs5NUjUnRB1Hj/I+HT2Fsf0VtO eQHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3ZdTKdjXZPsSu57R08aDOC5nHrf6U05QdlzIh/dh4Ps=; b=BxNcAI4oycqIUMV8BvRg6YxEz2bsN03db2ipx/L2ON2K6YQ/tpGkW8xUB7KrwdzI/l KV3uISFFcgrxcdFsazntrQDPyX7gBHtd4UwS8nTIMWzG5zVm+a7ec+i02IBJFk+Nqhdg orl65HzNfVKDsf9gwq2l0RAcWOUGlmFB4MHTvpP3Dfftw/X4fI36/NoCeLy2eCnQbWRy /Is4HnaFIhHfGQrQ1RApR5cyt9b6IE73Ec9lyuwt2qmKu8z9HHM+L+BDlKIrHVCAEHW7 6GenS7IzgRrZim765dYHzHsil6qe+agP14eWvRYSjcnx/tDYDbpRi0EvxuhkYSBTCLjZ GFlg== X-Gm-Message-State: AFqh2kpPHMsCC9yM/P0Rqbt9hEcnn8GHJPkle3Hg8q5Jqudpd8/wQBYf 1y2zSL4rd4f7LSyrzyyMDXgC/h4xGOTdyGzg X-Google-Smtp-Source: AMrXdXsOD/ByCSMxbnJmCup3o2AJFoHZjy+xlE/DW9pQzns3P70ql31A0nctj1QwdzY+4yzvgRaUyA== X-Received: by 2002:aa7:83d1:0:b0:580:d71e:a2e5 with SMTP id j17-20020aa783d1000000b00580d71ea2e5mr3089327pfn.22.1671895104676; Sat, 24 Dec 2022 07:18:24 -0800 (PST) Received: from stoup.. (76-14-210-194.or.wavecable.com. [76.14.210.194]) by smtp.gmail.com with ESMTPSA id t64-20020a625f43000000b005774f19b41csm4231124pfb.88.2022.12.24.07.18.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 24 Dec 2022 07:18:24 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: iii@linux.ibm.com Subject: [PATCH 2/4] accel/tcg: Use g_free_rcu for user-exec interval trees Date: Sat, 24 Dec 2022 07:18:19 -0800 Message-Id: <20221224151821.464455-3-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221224151821.464455-1-richard.henderson@linaro.org> References: <20221224151821.464455-1-richard.henderson@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::42c; envelope-from=richard.henderson@linaro.org; helo=mail-pf1-x42c.google.com 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Because we allow lockless lookups, we have to be careful when it is freed. Use rcu to delay the free until safe. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé --- accel/tcg/user-exec.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c index a3cecda405..2c5c10d2e6 100644 --- a/accel/tcg/user-exec.c +++ b/accel/tcg/user-exec.c @@ -22,6 +22,7 @@ #include "exec/exec-all.h" #include "tcg/tcg.h" #include "qemu/bitops.h" +#include "qemu/rcu.h" #include "exec/cpu_ldst.h" #include "exec/translate-all.h" #include "exec/helper-proto.h" @@ -136,6 +137,7 @@ bool handle_sigsegv_accerr_write(CPUState *cpu, sigset_t *old_set, } typedef struct PageFlagsNode { + struct rcu_head rcu; IntervalTreeNode itree; int flags; } PageFlagsNode; @@ -266,7 +268,7 @@ static bool pageflags_unset(target_ulong start, target_ulong last) } } else if (p_last <= last) { /* Range completely covers node -- remove it. */ - g_free(p); + g_free_rcu(p, rcu); } else { /* Truncate the node from the start. */ p->itree.start = last + 1; @@ -311,7 +313,7 @@ static void pageflags_create_merge(target_ulong start, target_ulong last, if (prev) { if (next) { prev->itree.last = next->itree.last; - g_free(next); + g_free_rcu(next, rcu); } else { prev->itree.last = last; } @@ -376,7 +378,7 @@ static bool pageflags_set_clear(target_ulong start, target_ulong last, p->flags = merge_flags; } else { interval_tree_remove(&p->itree, &pageflags_root); - g_free(p); + g_free_rcu(p, rcu); } goto done; } @@ -421,7 +423,7 @@ static bool pageflags_set_clear(target_ulong start, target_ulong last, p->flags = merge_flags; } else { interval_tree_remove(&p->itree, &pageflags_root); - g_free(p); + g_free_rcu(p, rcu); } if (p_last < last) { start = p_last + 1; @@ -462,7 +464,7 @@ static bool pageflags_set_clear(target_ulong start, target_ulong last, p->itree.start = last + 1; interval_tree_insert(&p->itree, &pageflags_root); } else { - g_free(p); + g_free_rcu(p, rcu); goto restart; } if (set_flags) { @@ -779,6 +781,7 @@ tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr, #define TBD_MASK (TARGET_PAGE_MASK * TPD_PAGES) typedef struct TargetPageDataNode { + struct rcu_head rcu; IntervalTreeNode itree; char data[TPD_PAGES][TARGET_PAGE_DATA_SIZE] __attribute__((aligned)); } TargetPageDataNode; @@ -801,11 +804,11 @@ void page_reset_target_data(target_ulong start, target_ulong end) n = next, next = next ? interval_tree_iter_next(n, start, last) : NULL) { target_ulong n_start, n_last, p_ofs, p_len; - TargetPageDataNode *t; + TargetPageDataNode *t = container_of(n, TargetPageDataNode, itree); if (n->start >= start && n->last <= last) { interval_tree_remove(n, &targetdata_root); - g_free(n); + g_free_rcu(t, rcu); continue; } @@ -819,7 +822,6 @@ void page_reset_target_data(target_ulong start, target_ulong end) n_last = MIN(last, n->last); p_len = (n_last + 1 - n_start) >> TARGET_PAGE_BITS; - t = container_of(n, TargetPageDataNode, itree); memset(t->data[p_ofs], 0, p_len * TARGET_PAGE_DATA_SIZE); } }