From patchwork Thu Jun 24 10:00:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 12341701 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 75B2AC48BDF for ; Thu, 24 Jun 2021 10:01:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5816E613FB for ; Thu, 24 Jun 2021 10:01:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232019AbhFXKDW (ORCPT ); Thu, 24 Jun 2021 06:03:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:58909 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231968AbhFXKDW (ORCPT ); Thu, 24 Jun 2021 06:03:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624528862; 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; bh=rzIFYAbX1OQ4bIQdeDioVYM8BAONDbVt0DgaCifv+NU=; b=KT6xxXZ1+TfEgooyWFzw8ArC20TnETTB5ycJq32AfQudJ1bGDh3MwCU4Kex7QqMtDfdTr2 NVo6iiKYKSOgZb57L7WaEOeICA/uFC0obeSW87QrzYPdmuJUFezke/ftjC7V3POLPkOzhl io2/BVuMskaX9LS0nrHZMVNWcgfjU7M= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-121-W3dbYDRYPcCIqbxYQAqZ-A-1; Thu, 24 Jun 2021 06:01:01 -0400 X-MC-Unique: W3dbYDRYPcCIqbxYQAqZ-A-1 Received: by mail-wm1-f69.google.com with SMTP id v2-20020a7bcb420000b0290146b609814dso1439559wmj.0 for ; Thu, 24 Jun 2021 03:01:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=rzIFYAbX1OQ4bIQdeDioVYM8BAONDbVt0DgaCifv+NU=; b=nyTsGt8j42cVvLaR29QgkaCWGHOKqZU0qCdmUFEbGrKoWtaURjijCsmuUgYVVW/Lqb 1rhldIl/roTmnrXK2e/oyqK09cU94WZzKdsxibBA43ABtJwbFfYWfBV8VZQlBobJfcAg X0hdC5lILxSaypd7gBfGTZr62LDEJxnn1IUXLogWwymNvEr98artUVUIeQKYwwySieCe TngYwR5D8tNrINrfLiU/UnkSQx2szcFbGt9fDo2vWyxCAgFJc0C+wHW4l+lknlfeo06k WAAIHuOIrppn0yhqAk6P5MqTLDLP4NdxoH+th1pnwz6oow5TGyjnQmY9dIbPgiiwseBT n8rw== X-Gm-Message-State: AOAM5325JJnRHBZqLleW8Ja2o4e1qpkJyjdU5nyfXUB+C99Vvjtoh+qT q7VdG7xJxp07DgERx4Qjy1MmDwNaa8HW/sJsTdzuL1y2X7Hqvav7i86IXZiIMPPP5ZjDQDboJGG vBTBzcitumEQuC4OpV7Qd X-Received: by 2002:adf:ba07:: with SMTP id o7mr3439749wrg.160.1624528860264; Thu, 24 Jun 2021 03:01:00 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzeimKsE0r9piJOMQLtnTnDHj81fVS/33+xCr49yJiQvgodxDeD/ZNvC3kb5P9+JgwFazpHYw== X-Received: by 2002:adf:ba07:: with SMTP id o7mr3439734wrg.160.1624528860096; Thu, 24 Jun 2021 03:01:00 -0700 (PDT) Received: from vian.redhat.com ([2a0c:5a80:3d14:2800:933d:abfc:d8e4:637f]) by smtp.gmail.com with ESMTPSA id u15sm7986819wmq.48.2021.06.24.03.00.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Jun 2021 03:00:59 -0700 (PDT) From: Nicolas Saenz Julienne To: jic23@kernel.org, lars@metafoo.de, linux-iio@vger.kernel.org Cc: linux-kernel@vger.kernel.org, nsaenzju@redhat.com, matt.ranostay@konsulko.com, andy.shevchenko@gmail.com Subject: [PATCH] iio: chemical: atlas-sensor: Avoid using irq_work Date: Thu, 24 Jun 2021 12:00:46 +0200 Message-Id: <20210624100046.1037159-1-nsaenzju@redhat.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The atlas sensor driver currently registers a threaded IRQ handler whose sole responsibility is to trigger an irq_work which will in turn run iio_trigger_poll() in IRQ context. This seems overkill given the fact that there already was a opportunity to run iio_trigger_poll() in IRQ context in the top half of the IRQ handler. So make use of it, ultimately avoiding a context switch, an IPI, and reducing latency. Signed-off-by: Nicolas Saenz Julienne --- NOTE: This was only compile tested. I don't know much about iio_triggers (or iio for that matter), but while reviewing irq_work usage this showed up and seemed trivial enough to fix right away. There might be a subtle reason why this is setup as such, but it would at least warrant a comment. drivers/iio/chemical/atlas-sensor.c | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-) diff --git a/drivers/iio/chemical/atlas-sensor.c b/drivers/iio/chemical/atlas-sensor.c index 9cb99585b6ff..710daa169d57 100644 --- a/drivers/iio/chemical/atlas-sensor.c +++ b/drivers/iio/chemical/atlas-sensor.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include #include @@ -89,7 +88,6 @@ struct atlas_data { struct iio_trigger *trig; struct atlas_device *chip; struct regmap *regmap; - struct irq_work work; unsigned int interrupt_enabled; /* 96-bit data + 32-bit pad + 64-bit timestamp */ __be32 buffer[6] __aligned(8); @@ -442,13 +440,6 @@ static const struct iio_buffer_setup_ops atlas_buffer_setup_ops = { .predisable = atlas_buffer_predisable, }; -static void atlas_work_handler(struct irq_work *work) -{ - struct atlas_data *data = container_of(work, struct atlas_data, work); - - iio_trigger_poll(data->trig); -} - static irqreturn_t atlas_trigger_handler(int irq, void *private) { struct iio_poll_func *pf = private; @@ -474,7 +465,7 @@ static irqreturn_t atlas_interrupt_handler(int irq, void *private) struct iio_dev *indio_dev = private; struct atlas_data *data = iio_priv(indio_dev); - irq_work_queue(&data->work); + iio_trigger_poll(data->trig); return IRQ_HANDLED; } @@ -677,12 +668,10 @@ static int atlas_probe(struct i2c_client *client, goto unregister_trigger; } - init_irq_work(&data->work, atlas_work_handler); - if (client->irq > 0) { /* interrupt pin toggles on new conversion */ ret = devm_request_threaded_irq(&client->dev, client->irq, - NULL, atlas_interrupt_handler, + atlas_interrupt_handler, NULL, IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "atlas_irq",