Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757296AbaKTJh5 (ORCPT ); Thu, 20 Nov 2014 04:37:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58737 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756136AbaKTJhz (ORCPT ); Thu, 20 Nov 2014 04:37:55 -0500 From: Vitaly Kuznetsov To: Dexuan Cui Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, driverdev-devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, jasowang@redhat.com, kys@microsoft.com, haiyangz@microsoft.com Subject: Re: [PATCH v2] tools: hv: ignore ENOBUFS and ENOMEM in the KVP daemon References: <1416462682-28236-1-git-send-email-decui@microsoft.com> Date: Thu, 20 Nov 2014 10:37:40 +0100 In-Reply-To: <1416462682-28236-1-git-send-email-decui@microsoft.com> (Dexuan Cui's message of "Wed, 19 Nov 2014 21:51:22 -0800") Message-ID: <87fvdedxgb.fsf@vitty.brq.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dexuan Cui writes: > Under high memory pressure and very high KVP R/W test pressure, the netlink > recvfrom() may transiently return ENOBUFS to the daemon -- we found this > during a 2-week stress test. > > We'd better not terminate the daemon on the failure, because a typical KVP > user will re-try the R/W and hopefully it will succeed next time. > > We can also ignore the errors on sending. > > Cc: Vitaly Kuznetsov > Cc: K. Y. Srinivasan > Signed-off-by: Dexuan Cui > --- > > v2: I also ignore the errors on sending, as Vitaly suggested. Thanks, Reviewed-by: Vitaly Kuznetsov > > tools/hv/hv_kvp_daemon.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c > index 22b0764..6a6432a 100644 > --- a/tools/hv/hv_kvp_daemon.c > +++ b/tools/hv/hv_kvp_daemon.c > @@ -1559,8 +1559,15 @@ int main(int argc, char *argv[]) > addr_p, &addr_l); > > if (len < 0) { > + int saved_errno = errno; > syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s", > addr.nl_pid, errno, strerror(errno)); > + > + if (saved_errno == ENOBUFS) { > + syslog(LOG_ERR, "receive error: ignored"); > + continue; > + } > + > close(fd); > return -1; > } > @@ -1763,8 +1770,15 @@ kvp_done: > > len = netlink_send(fd, incoming_cn_msg); > if (len < 0) { > + int saved_errno = errno; > syslog(LOG_ERR, "net_link send failed; error: %d %s", errno, > strerror(errno)); > + > + if (saved_errno == ENOMEM || saved_errno == ENOBUFS) { > + syslog(LOG_ERR, "send error: ignored"); > + continue; > + } > + > exit(EXIT_FAILURE); > } > } -- Vitaly -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/