From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CF4AC64E7C for ; Thu, 26 Nov 2020 13:30:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C581821D46 for ; Thu, 26 Nov 2020 13:30:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="buBUq5lH"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="/2A0sdDG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390074AbgKZNae (ORCPT ); Thu, 26 Nov 2020 08:30:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390059AbgKZNad (ORCPT ); Thu, 26 Nov 2020 08:30:33 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72D10C061A04 for ; Thu, 26 Nov 2020 05:30:33 -0800 (PST) From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1606397432; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ISkd7gV5GLtaW758unEPO6qObTdATD8RZJ4kXQk49Fg=; b=buBUq5lH2wBNsm0mh1CFOY5ICwo+EUCNEo2vPfCMW0mlGdTRZGabaFEyI9Wy7jq7Wi5a88 h1MWgmQyVPQnhOy+JIAUBwTQ9rKUiq83sizFhTcLXkaK+F0m+z78cc4XjWzVLc4n1QkuMg NbHCVsF3wk4xJQfJeb3hF7tah+I6PyIH0pclW164Fy1COrklcZTHrD9uvVppNWt0EbNVuW y3/iAXTWxT8UeO6yv26oolpLx3cvzzkomqq6RkZmGMrkOKjiP9F2RWsb/WhabJS2z4Uuum P2k/7HE4LA4xBpjSmuP2s8+M0pXVg+HUnNtIDpL0SYD9cIgcF5HiB4Xn7JHoTw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1606397432; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ISkd7gV5GLtaW758unEPO6qObTdATD8RZJ4kXQk49Fg=; b=/2A0sdDG3ovvGVDOLX1NfOS7ZR747K6YIFIMFSrFK4ZC3DK9qHK8t2L4vZsEO0kHzkSuG3 SvyerGNClnjeOHAQ== To: linux-scsi@vger.kernel.org Cc: Finn Thain , GR-QLogic-Storage-Upstream@marvell.com, Hannes Reinecke , Jack Wang , John Garry , linux-m68k@lists.linux-m68k.org, Manish Rangankar , Michael Schmitz , MPT-FusionLinux.pdl@broadcom.com, Nilesh Javali , Sathya Prakash , Sreekanth Reddy , Suganath Prabu Subramani , Vikram Auradkar , Xiang Chen , Xiaofei Tan , "James E . J . Bottomley" , "Martin K . Petersen" , Thomas Gleixner , "Ahmed S . Darwish" , Sebastian Andrzej Siewior Subject: [PATCH 04/14] scsi: qla2xxx: qla82xx: Remove in_interrupt(). Date: Thu, 26 Nov 2020 14:29:42 +0100 Message-Id: <20201126132952.2287996-5-bigeasy@linutronix.de> In-Reply-To: <20201126132952.2287996-1-bigeasy@linutronix.de> References: <20201126132952.2287996-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-m68k@vger.kernel.org From: "Ahmed S. Darwish" qla82xx_idc_lock() spins on a certain hardware state until it's updated. At the end of each spin, if in_interrupt() is true, it does 20 loops of cpu_relax(). Otherwise, it yields the CPU. While in_interrupt() is ill-defined and does not provide what the name suggests, it is not needed here: qla82xx_idc_lock() is always called from process context. Below is an analysis of its callers, in order of appearance: - qla_nx.c: qla82xx_device_bootstrap(), only called by qla82xx_device_state_handler(), has multiple msleep()s. - qla_nx.c: qla82xx_need_qsnt_handler(), has one second msleep() - qla_nx.c: qla82xx_wait_for_state_change(), one second msleep() - qla_nx.c: qla82xx_need_reset_handler(), can sleep up to 10 seconds - qla_nx.c: qla82xx_device_state_handler(), has multiple msleep()s - qla_nx.c: qla82xx_abort_isp(), if it's a qla82xx controller, calls qla82xx_device_state_handler(), which sleeps. It's also bound to isp_operations ->abort_isp() hook, where all the callers are in process context. - qla_nx.c: qla82xx_beacon_on(), bound to isp_operations ->beacon_on() hook. That hook is only called once, in a mutex locked context, from qla2x00_beacon_store(). - qla_nx.c: qla82xx_beacon_off(), bound to isp_operations ->beacon_off() hook. Like ->beacon_on(), it's only called once, in a mutex locked context, from qla2x00_beacon_store(). - qla_nx.c: qla82xx_fw_dump(), calls qla2x00_wait_for_chip_reset(), which has msleep() in a loop. It is bound to isp_operations ->fw_dump() hook. That hook *is* called from atomic context at qla_isr.c by multiple interrupt handlers. Nonetheless, it's other controllers interrupt handlers, and not the qla82xx. - qla_attr.c: qla2x00_sysfs_write_fw_dump(), and qla2x00_sysfs_write_reset(), process-context sysfs ->write() hooks. - qla_os.c: qla2x00_probe_one(). PCI ->probe(), process context. - qla_os.c: qla2x00_clear_drv_active(), called solely from qla2x00_remove_one(), which is PCI ->remove() hook, process context. - qla_os.c: qla2x00_do_dpc(), kthread function, process context. Remove the in_interrupt() check. Change qla82xx_idc_lock() specification to a purely process-context function. Mark it with "Context: task, might sleep". Change qla82xx_idc_lock() implementation to sleep 100ms, instead of a schedule(), for each spin. This is more deterministic, and it matches the other qla models idc_lock() functions. Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Cc: Nilesh Javali Cc: --- drivers/scsi/qla2xxx/qla_def.h | 5 +++++ drivers/scsi/qla2xxx/qla_nx.c | 25 +++++++++++-------------- 2 files changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h index ed9b10f8537d6..fe3c0e2f1ce88 100644 --- a/drivers/scsi/qla2xxx/qla_def.h +++ b/drivers/scsi/qla2xxx/qla_def.h @@ -3296,8 +3296,10 @@ struct isp_operations { void (*fw_dump)(struct scsi_qla_host *vha); void (*mpi_fw_dump)(struct scsi_qla_host *, int); =20 + /* Context: task, might sleep */ int (*beacon_on) (struct scsi_qla_host *); int (*beacon_off) (struct scsi_qla_host *); + void (*beacon_blink) (struct scsi_qla_host *); =20 void *(*read_optrom)(struct scsi_qla_host *, void *, @@ -3308,7 +3310,10 @@ struct isp_operations { int (*get_flash_version) (struct scsi_qla_host *, void *); int (*start_scsi) (srb_t *); int (*start_scsi_mq) (srb_t *); + + /* Context: task, might sleep */ int (*abort_isp) (struct scsi_qla_host *); + int (*iospace_config)(struct qla_hw_data *); int (*initialize_adapter)(struct scsi_qla_host *); }; diff --git a/drivers/scsi/qla2xxx/qla_nx.c b/drivers/scsi/qla2xxx/qla_nx.c index b3ba0de5d4fb8..b2017f1c35044 100644 --- a/drivers/scsi/qla2xxx/qla_nx.c +++ b/drivers/scsi/qla2xxx/qla_nx.c @@ -489,29 +489,26 @@ qla82xx_rd_32(struct qla_hw_data *ha, ulong off_in) return data; } =20 -#define IDC_LOCK_TIMEOUT 100000000 +/* + * Context: task, might sleep + */ int qla82xx_idc_lock(struct qla_hw_data *ha) { - int i; - int done =3D 0, timeout =3D 0; + const int delay_ms =3D 100, timeout_ms =3D 2000; + int done, total =3D 0; =20 - while (!done) { + might_sleep(); + + while (true) { /* acquire semaphore5 from PCI HW block */ done =3D qla82xx_rd_32(ha, QLA82XX_PCIE_REG(PCIE_SEM5_LOCK)); if (done =3D=3D 1) break; - if (timeout >=3D IDC_LOCK_TIMEOUT) + if (WARN_ON_ONCE(total >=3D timeout_ms)) return -1; =20 - timeout++; - - /* Yield CPU */ - if (!in_interrupt()) - schedule(); - else { - for (i =3D 0; i < 20; i++) - cpu_relax(); - } + total +=3D delay_ms; + msleep(delay_ms); } =20 return 0; --=20 2.29.2