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(unknown [2a02:6bf:8080:894::1:13]) by mail-nwsmtp-smtp-corp-main-56.klg.yp-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id b5mcgZ0FDuQ0-bigdVyc1; Fri, 28 Nov 2025 23:05:38 +0300 Precedence: bulk X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1764360338; bh=Ug2xojQAwutgyKxatHFJVtNcr8aNK9EqFdIW+a5P3V0=; h=Cc:Message-ID:References:Date:In-Reply-To:Subject:To:From; b=dClwPu5ao8v2imsNBiyM6DGdT7TmhBtwhyt/bLu+g9T4cTqLoSha5EXRt4HCAvmxP j+xeA19O8M4fPxeqyl8+xmHj0QJk8PxZuW4GXFGKHna8cUpFD+EXQ7YEYJtDYjfone CWwsvW3AMgAlnXYM8xqziHhJIUoq3b4ThKZi3ZJg= Authentication-Results: mail-nwsmtp-smtp-corp-main-56.klg.yp-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Vladimir Sementsov-Ogievskiy To: marcandre.lureau@redhat.com Cc: pbonzini@redhat.com, armbru@redhat.com, eblake@redhat.com, berrange@redhat.com, vsementsov@yandex-team.ru, yc-core@yandex-team.ru, d-tatianin@yandex-team.ru, qemu-devel@nongnu.org Subject: [RFC PATCH 1/3] char: qemu_chr_write_log() use qemu_write_full() Date: Fri, 28 Nov 2025 23:05:33 +0300 Message-ID: <20251128200536.207344-2-vsementsov@yandex-team.ru> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20251128200536.207344-1-vsementsov@yandex-team.ru> References: <20251128200536.207344-1-vsementsov@yandex-team.ru> 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=178.154.239.200; envelope-from=vsementsov@yandex-team.ru; helo=forwardcorp1d.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 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @yandex-team.ru) X-ZM-MESSAGEID: 1764360409260019200 logfd is blocking, so we don't need to care about EAGAIN. Let's simply use qemu_write_full(). Signed-off-by: Vladimir Sementsov-Ogievskiy --- Honestly, I'm not sure, may be EAGAIN handling is needed for some non-linux OSes? That's why it's RFC.. The original commit 0d7708ba29cbcc34336 "qemu-char: add logfile facility to all chardev backends" doen't mention, why should we handle EAGAIN. chardev/char.c | 22 +++++----------------- 1 file changed, 5 insertions(+), 17 deletions(-) diff --git a/chardev/char.c b/chardev/char.c index 3e432195a5..64006a3119 100644 --- a/chardev/char.c +++ b/chardev/char.c @@ -82,29 +82,17 @@ void qemu_chr_be_event(Chardev *s, QEMUChrEvent event) CHARDEV_GET_CLASS(s)->chr_be_event(s, event); } =20 -/* Not reporting errors from writing to logfile, as logs are - * defined to be "best effort" only */ static void qemu_chr_write_log(Chardev *s, const uint8_t *buf, size_t len) { - size_t done =3D 0; - ssize_t ret; - if (s->logfd < 0) { return; } =20 - while (done < len) { - retry: - ret =3D write(s->logfd, buf + done, len - done); - if (ret =3D=3D -1 && errno =3D=3D EAGAIN) { - g_usleep(100); - goto retry; - } - - if (ret <=3D 0) { - return; - } - done +=3D ret; + if (qemu_write_full(s->logfd, buf, len) < len) { + /* + * qemu_write_full() is defined with G_GNUC_WARN_UNUSED_RESULT, + * but logging is best=E2=80=91effort, we do ignore errors. + */ } } =20 --=20 2.48.1