From patchwork Mon Jul 22 21:53:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lina Iyer X-Patchwork-Id: 11053553 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BA7C1912 for ; Mon, 22 Jul 2019 21:53:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A947F22362 for ; Mon, 22 Jul 2019 21:53:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9AE4B26E40; Mon, 22 Jul 2019 21:53:55 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 141C922362 for ; Mon, 22 Jul 2019 21:53:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731580AbfGVVxy (ORCPT ); Mon, 22 Jul 2019 17:53:54 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:36528 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730704AbfGVVxy (ORCPT ); Mon, 22 Jul 2019 17:53:54 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 8AA8C616B9; Mon, 22 Jul 2019 21:53:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1563832433; bh=be9/QsL0swCk3x3llqIibWSVJSbE8k9VDv03K/wu/Fc=; h=From:To:Cc:Subject:Date:From; b=NTlEin5mIThygbNaJX/yGWRbwSku1nLraSYm8sQmFu3Kb7rWrO+Q3FuSPI59T18QY UQTl/WTjhZAeFFwtH5am8sHqJ49BuYeZy65ZbPZU1nMunwVNymTu+Sg7aPzVrVVw42 ut8Of7huOXAwof3USLZy59CQ2zarSmFf1tJrGIc0= Received: from codeaurora.org (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: ilina@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3112B604BE; Mon, 22 Jul 2019 21:53:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1563832433; bh=be9/QsL0swCk3x3llqIibWSVJSbE8k9VDv03K/wu/Fc=; h=From:To:Cc:Subject:Date:From; b=NTlEin5mIThygbNaJX/yGWRbwSku1nLraSYm8sQmFu3Kb7rWrO+Q3FuSPI59T18QY UQTl/WTjhZAeFFwtH5am8sHqJ49BuYeZy65ZbPZU1nMunwVNymTu+Sg7aPzVrVVw42 ut8Of7huOXAwof3USLZy59CQ2zarSmFf1tJrGIc0= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3112B604BE Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=ilina@codeaurora.org From: Lina Iyer To: agross@kernel.org, bjorn.andersson@linaro.org, swboyd@chromium.org Cc: linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, rnayak@codeaurora.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, dianders@chromium.org, mkshah@codeaurora.org, "Raju P.L.S.S.S.N" , Lina Iyer Subject: [PATCH V2 1/4] drivers: qcom: rpmh-rsc: simplify TCS locking Date: Mon, 22 Jul 2019 15:53:37 -0600 Message-Id: <20190722215340.3071-1-ilina@codeaurora.org> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Raju P.L.S.S.S.N" The tcs->lock was introduced to serialize access with in TCS group. But, drv->lock is still needed to synchronize core aspects of the communication. This puts the drv->lock in the critical and high latency path of sending a request. drv->lock provides the all necessary synchronization. So remove locking around TCS group and simply use the drv->lock instead. Signed-off-by: Raju P.L.S.S.S.N [ilina: split patch into multiple files, update commit text] Signed-off-by: Lina Iyer --- Changes in v2: - Split the patches into multiple - Optimzation to remove reundant TCS access - Split the rpmh library changes into its own patch - Remove locks in IRQ handler - Update commit text - Remove fixes in commit text --- drivers/soc/qcom/rpmh-internal.h | 2 -- drivers/soc/qcom/rpmh-rsc.c | 32 ++++++++++++-------------------- 2 files changed, 12 insertions(+), 22 deletions(-) diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index a7bbbb67991c..969d5030860e 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -28,7 +28,6 @@ struct rsc_drv; * @offset: start of the TCS group relative to the TCSes in the RSC * @num_tcs: number of TCSes in this type * @ncpt: number of commands in each TCS - * @lock: lock for synchronizing this TCS writes * @req: requests that are sent from the TCS * @cmd_cache: flattened cache of cmds in sleep/wake TCS * @slots: indicates which of @cmd_addr are occupied @@ -40,7 +39,6 @@ struct tcs_group { u32 offset; int num_tcs; int ncpt; - spinlock_t lock; const struct tcs_request *req[MAX_TCS_PER_TYPE]; u32 *cmd_cache; DECLARE_BITMAP(slots, MAX_TCS_SLOTS); diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index e278fc11fe5c..5ede8d6de3ad 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -106,26 +106,26 @@ static int tcs_invalidate(struct rsc_drv *drv, int type) { int m; struct tcs_group *tcs; + int ret = 0; tcs = get_tcs_of_type(drv, type); - spin_lock(&tcs->lock); - if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) { - spin_unlock(&tcs->lock); - return 0; - } + spin_lock(&drv->lock); + if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) + goto done_invalidate; for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) { if (!tcs_is_free(drv, m)) { - spin_unlock(&tcs->lock); - return -EAGAIN; + ret = -EAGAIN; + goto done_invalidate; } write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0); write_tcs_reg_sync(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, m, 0); } bitmap_zero(tcs->slots, MAX_TCS_SLOTS); - spin_unlock(&tcs->lock); +done_invalidate: + spin_unlock(&drv->lock); return 0; } @@ -349,41 +349,35 @@ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) { struct tcs_group *tcs; int tcs_id; - unsigned long flags; int ret; tcs = get_tcs_for_msg(drv, msg); if (IS_ERR(tcs)) return PTR_ERR(tcs); - spin_lock_irqsave(&tcs->lock, flags); spin_lock(&drv->lock); /* * The h/w does not like if we send a request to the same address, * when one is already in-flight or being processed. */ ret = check_for_req_inflight(drv, tcs, msg); - if (ret) { - spin_unlock(&drv->lock); + if (ret) goto done_write; - } tcs_id = find_free_tcs(tcs); if (tcs_id < 0) { ret = tcs_id; - spin_unlock(&drv->lock); goto done_write; } tcs->req[tcs_id - tcs->offset] = msg; set_bit(tcs_id, drv->tcs_in_use); - spin_unlock(&drv->lock); __tcs_buffer_write(drv, tcs_id, 0, msg); __tcs_trigger(drv, tcs_id); done_write: - spin_unlock_irqrestore(&tcs->lock, flags); + spin_unlock(&drv->lock); return ret; } @@ -481,19 +475,18 @@ static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg) { struct tcs_group *tcs; int tcs_id = 0, cmd_id = 0; - unsigned long flags; int ret; tcs = get_tcs_for_msg(drv, msg); if (IS_ERR(tcs)) return PTR_ERR(tcs); - spin_lock_irqsave(&tcs->lock, flags); + spin_lock(&drv->lock); /* find the TCS id and the command in the TCS to write to */ ret = find_slots(tcs, msg, &tcs_id, &cmd_id); if (!ret) __tcs_buffer_write(drv, tcs_id, cmd_id, msg); - spin_unlock_irqrestore(&tcs->lock, flags); + spin_unlock(&drv->lock); return ret; } @@ -584,7 +577,6 @@ static int rpmh_probe_tcs_config(struct platform_device *pdev, tcs->type = tcs_cfg[i].type; tcs->num_tcs = tcs_cfg[i].n; tcs->ncpt = ncpt; - spin_lock_init(&tcs->lock); if (!tcs->num_tcs || tcs->type == CONTROL_TCS) continue;