From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3525117-1516539116-2-13544543373610863560 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, RCVD_IN_DNSWL_MED -2.3, SPF_PASS -0.001, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='140.211.166.138', Host='smtp1.osuosl.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='us-ascii' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: driverdev-devel-bounces@linuxdriverproject.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1516539115; b=AviF2tL3NQhbEUb//Ys/Gzkc1Lw7ionsl8cQf7fTx5+Evyw i/ufvI4NkVKXsEGtsFd7eFMUFd+dRtetnYwnrQ0I85e3amifvbfCpYHCqpo5h8lD 7YnQmS908PMEaiBqT8KpdAI+1zOK2F+z1m6eWBlhEYHeSot5erp2mLN1R0ol/qPm deZmpHR/UKLNzw7QUkaKHePo5d18qZrBmVOZhSisKoio1JOxhCkdo1SulMUlKRL2 24CyQ5v2sHUhhwQ7GnjqaMUsXTyQDk799lIzRYBmKYqYrUMw/9bqUOQAT3dB4Yo1 4W1hrgaQexecJYmjtNRUsjNEbnqD6lVXS8vlhzw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=date:from:to:subject:message-id :in-reply-to:references:mime-version:list-id:list-unsubscribe :list-archive:list-post:list-help:list-subscribe:cc:content-type :content-transfer-encoding:sender; s=arctest; t=1516539115; bh=u WwSWa/tJTgNvov3puabdvViUC2hrrh5hAnVRskDtUg=; b=DdrrEQhx1MuL+viSF 7wj63W5Kmt3gBih+l+LOJQXGUBfyNgDQmnvQ5AWeR7VXwsobTbsEACz5huAeflaq pPyVZr3fTzq2UEpEn0mqGRrZ6XysZzM6L+V5CNDzIVYggf6NUQ1cZ3ZbrqScD6Mh RznayukGpH0Qq/4AxOSlxs0boMw3zFX5qJqe5LnDfD7RnANpcNDNiUzWsQXYk/q8 VnP2R8qAQM3UkTBFh0AMioSa3eMSmV5c7I0O97gUl4lDuIM9RUtO+NLWgemGwNEE JyoCEVghdDSJcZTResGNcyVGBWpey6Ve79o9lWmb4CwQCdSuRxb/zdxcji8xJF6s ngLbw== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=140.211.166.138 (smtp1.osuosl.org); spf=pass smtp.mailfrom=driverdev-devel-bounces@linuxdriverproject.org smtp.helo=whitealder.osuosl.org; x-aligned-from=fail; x-ptr=fail x-ptr-helo=whitealder.osuosl.org x-ptr-lookup=smtp1.osuosl.org; x-return-mx=pass smtp.domain=linuxdriverproject.org smtp.result=pass smtp_is_org_domain=yes header.domain=kernel.org header.result=pass header_is_org_domain=yes; x-tls=pass version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128 Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=140.211.166.138 (smtp1.osuosl.org); spf=pass smtp.mailfrom=driverdev-devel-bounces@linuxdriverproject.org smtp.helo=whitealder.osuosl.org; x-aligned-from=fail; x-ptr=fail x-ptr-helo=whitealder.osuosl.org x-ptr-lookup=smtp1.osuosl.org; x-return-mx=pass smtp.domain=linuxdriverproject.org smtp.result=pass smtp_is_org_domain=yes header.domain=kernel.org header.result=pass header_is_org_domain=yes; x-tls=pass version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128 X-Remote-Delivered-To: driverdev-devel@osuosl.org DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2437B214E1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=jic23@kernel.org Date: Sun, 21 Jan 2018 12:51:36 +0000 From: Jonathan Cameron To: Shreeya Patel Subject: Re: [PATCH] Staging: iio: ade7758: Replace mlock with buf_lock Message-ID: <20180121125136.5a386ec8@archlinux> In-Reply-To: <1516463088-2514-1-git-send-email-shreeya.patel23498@gmail.com> References: <1516463088-2514-1-git-send-email-shreeya.patel23498@gmail.com> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-BeenThere: driverdev-devel@linuxdriverproject.org X-Mailman-Version: 2.1.24 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devel@driverdev.osuosl.org, lars@metafoo.de, Michael.Hennerich@analog.com, linux-iio@vger.kernel.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, pmeerw@pmeerw.net, knaack.h@gmx.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Sat, 20 Jan 2018 21:14:48 +0530 Shreeya Patel wrote: > iio_dev->mlock is to be used only by the IIO core for protecting > device mode changes between INDIO_DIRECT and INDIO_BUFFER. > > This patch replaces the use of mlock with the already established > buf_lock mutex. > > Signed-off-by: Shreeya Patel You can't do it this simply as it will cause deadlock due to nested locking of the buf_lock. To share the lock you will need to provide unlocked versions of the read and write functions and use those if the lock has already been taken. Jonathan > --- > drivers/staging/iio/meter/ade7758_core.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/staging/iio/meter/ade7758_core.c b/drivers/staging/iio/meter/ade7758_core.c > index 7b7ffe5..1a866cc 100644 > --- a/drivers/staging/iio/meter/ade7758_core.c > +++ b/drivers/staging/iio/meter/ade7758_core.c > @@ -523,12 +523,13 @@ static int ade7758_read_raw(struct iio_dev *indio_dev, > long mask) > { > int ret; > + struct ade7758_state *st = iio_priv(indio_dev); > > switch (mask) { > case IIO_CHAN_INFO_SAMP_FREQ: > - mutex_lock(&indio_dev->mlock); > + mutex_lock(&st->buf_lock); > ret = ade7758_read_samp_freq(&indio_dev->dev, val); > - mutex_unlock(&indio_dev->mlock); > + mutex_unlock(&st->buf_lock); > return ret; > default: > return -EINVAL; > @@ -542,14 +543,15 @@ static int ade7758_write_raw(struct iio_dev *indio_dev, > int val, int val2, long mask) > { > int ret; > + struct ade7758_state *st = iio_priv(indio_dev); > > switch (mask) { > case IIO_CHAN_INFO_SAMP_FREQ: > if (val2) > return -EINVAL; > - mutex_lock(&indio_dev->mlock); > + mutex_lock(&st->buf_lock); > ret = ade7758_write_samp_freq(&indio_dev->dev, val); > - mutex_unlock(&indio_dev->mlock); > + mutex_unlock(&st->buf_lock); > return ret; > default: > return -EINVAL; _______________________________________________ devel mailing list devel@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel