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[174.21.142.130]) by smtp.gmail.com with ESMTPSA id on10-20020a17090b1d0a00b001d08a7d569csm8154011pjb.56.2022.04.17.11.30.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 Apr 2022 11:30:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=hSJXBg/184u8r3uaJrOb0GqfAeU9RlxZON49hn1UzLA=; b=zHRI2GVEmflCky8UyVp4wHh2oZmcZMS72B5k6rZC88UPXnGyf2lNy/GWi05TAM8Xf/ SAEtJ2MPLEt9RhHt9/vrpaB6PODGtfjn73r7DFQJJ+zf1dx8suUq5MrYzFCvmc4rIGAC 0J3nyxzu4m1qwqEvmncUIEeNIbPzO34EJxr9NevAhphfeSOpSPaS7Blqpks5WUu98ZO9 odqGX9LUyTZon90ttc2baWvz0cajqgFE9cQfaM2wDRzOyAXw0sUJczLirjj+h7iCHHt/ +RFaDqy1dxEdpLzBsd4S2C/+cxE03jIS9re+z18LVlW8fsp4B2DssBgGznIAAt6p3O2l TzFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=hSJXBg/184u8r3uaJrOb0GqfAeU9RlxZON49hn1UzLA=; b=i4vFITsCaXe9oVZA1Zlpe8LoA3N12qh7oDfGR/Mciu2vs/H4rSuI79J+O9ofsCHpVr nELbKWeeiMU0TFcCneydFrMqMcMKC/1DuBjviZYi6L8GXQo+Q8wZu/X8LAlTuDsd+d6B m2NWXkE7jt2f6RWGUpUA0ehXaB/OHQTFq4Td/tMGQD/4nIwIsCujUwlxYwE08YT975tC HL32jaRMeTXeqdR07qAz59gv+yuRG3ZgmXw2zcIHDffrwoXYeTvonndlcTNDL3gFjWRo M5S7DGCW/Kxd8KNVFfsk6b+IAbdkO7p5Zlg3ADJUd6iZ/qDyp/B0AtRZbgzgym88J6Wy v6ig== X-Gm-Message-State: AOAM530R2ynGeWgVoFLEjc41cf9ezSdZ0CAVLsOch9VT8p471JoCg8OA fctmpXiLCtPsXRDPGRGmRbDHJvzhZG6W1A== X-Google-Smtp-Source: ABdhPJwBEQEYnJmI9SwWjaR07DIy5GlnpKYol/hbwQO3kInVcUtoqNuh50Exw+U3FJPYksVhfcjs/A== X-Received: by 2002:a17:90a:5647:b0:1d2:87a9:479a with SMTP id d7-20020a17090a564700b001d287a9479amr3444776pji.222.1650220221417; Sun, 17 Apr 2022 11:30:21 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PATCH v3 01/39] util/log: Drop manual log buffering Date: Sun, 17 Apr 2022 11:29:41 -0700 Message-Id: <20220417183019.755276-2-richard.henderson@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220417183019.755276-1-richard.henderson@linaro.org> References: <20220417183019.755276-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::1033; envelope-from=richard.henderson@linaro.org; helo=mail-pj1-x1033.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, T_SCC_BODY_TEXT_LINE=-0.01 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: , Cc: alex.bennee@linaro.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1650221766094100001 This buffering was introduced during the Paleozoic: 9fa3e853531. There has never been an explanation as to why we may not allow glibc to allocate the file buffer itself. We certainly have many other uses of mmap and malloc during user-only startup, so presumably whatever the issue was, it has been fixed during the preceeding 18 years. Reviewed-by: Alex Benn=C3=A9e Signed-off-by: Richard Henderson --- include/qemu/log.h | 1 - bsd-user/main.c | 1 - linux-user/main.c | 1 - util/log.c | 21 ++++----------------- 4 files changed, 4 insertions(+), 20 deletions(-) diff --git a/include/qemu/log.h b/include/qemu/log.h index 5739c7e6d8..ed59ebd4a2 100644 --- a/include/qemu/log.h +++ b/include/qemu/log.h @@ -148,7 +148,6 @@ typedef struct QEMULogItem { extern const QEMULogItem qemu_log_items[]; =20 void qemu_set_log(int log_flags); -void qemu_log_needs_buffers(void); void qemu_set_log_filename(const char *filename, Error **errp); void qemu_set_dfilter_ranges(const char *ranges, Error **errp); bool qemu_log_in_addr_range(uint64_t addr); diff --git a/bsd-user/main.c b/bsd-user/main.c index 88d347d05e..08f43af235 100644 --- a/bsd-user/main.c +++ b/bsd-user/main.c @@ -405,7 +405,6 @@ int main(int argc, char **argv) } =20 /* init debug */ - qemu_log_needs_buffers(); qemu_set_log_filename(log_file, &error_fatal); if (log_mask) { int mask; diff --git a/linux-user/main.c b/linux-user/main.c index fbc9bcfd5f..2b06350688 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -679,7 +679,6 @@ int main(int argc, char **argv, char **envp) =20 log_mask =3D last_log_mask | (enable_strace ? LOG_STRACE : 0); if (log_mask) { - qemu_log_needs_buffers(); qemu_set_log(log_mask); } =20 diff --git a/util/log.c b/util/log.c index 2ee1500bee..ffa66a267e 100644 --- a/util/log.c +++ b/util/log.c @@ -72,8 +72,6 @@ static void qemu_logfile_free(QemuLogFile *logfile) g_free(logfile); } =20 -static bool log_uses_own_buffers; - /* enable or disable low levels log */ void qemu_set_log(int log_flags) { @@ -121,29 +119,18 @@ void qemu_set_log(int log_flags) assert(!is_daemonized()); logfile->fd =3D stderr; } - /* must avoid mmap() usage of glibc by setting a buffer "by hand" = */ - if (log_uses_own_buffers) { - static char logfile_buf[4096]; =20 - setvbuf(logfile->fd, logfile_buf, _IOLBF, sizeof(logfile_buf)); - } else { #if defined(_WIN32) - /* Win32 doesn't support line-buffering, so use unbuffered out= put. */ - setvbuf(logfile->fd, NULL, _IONBF, 0); + /* Win32 doesn't support line-buffering, so use unbuffered output.= */ + setvbuf(logfile->fd, NULL, _IONBF, 0); #else - setvbuf(logfile->fd, NULL, _IOLBF, 0); + setvbuf(logfile->fd, NULL, _IOLBF, 0); #endif - log_append =3D 1; - } + log_append =3D 1; qatomic_rcu_set(&qemu_logfile, logfile); } } =20 -void qemu_log_needs_buffers(void) -{ - log_uses_own_buffers =3D true; -} - /* * Allow the user to include %d in their logfile which will be * substituted with the current PID. This is useful for debugging many --=20 2.25.1