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McKenney" To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, Eric Dumazet , linux-kernel@vger.kernel.org Subject: Re: [PATCH] Input: evdev - add a schedule point in evdev_write() Reply-To: paulmck@linux.ibm.com References: <20181005005359.GA218372@dtor-ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181005005359.GA218372@dtor-ws> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18100504-0052-0000-0000-0000033CC3A1 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009824; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000267; SDB=6.01098052; UDB=6.00567916; IPR=6.00878093; MB=3.00023621; MTD=3.00000008; XFM=3.00000015; UTC=2018-10-05 04:08:39 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18100504-0053-0000-0000-00005E4CE141 Message-Id: <20181005040836.GU2674@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-10-05_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810050041 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 04, 2018 at 05:53:59PM -0700, Dmitry Torokhov wrote: > Large writes to evdev interface may cause rcu stalls. Let's add > cond_resched() to the loop to avoid this. > > Signed-off-by: Dmitry Torokhov Reviewed-by: Paul E. McKenney > --- > drivers/input/evdev.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c > index 370206f987f9..f48369d6f3a0 100644 > --- a/drivers/input/evdev.c > +++ b/drivers/input/evdev.c > @@ -564,6 +564,7 @@ static ssize_t evdev_write(struct file *file, const char __user *buffer, > > input_inject_event(&evdev->handle, > event.type, event.code, event.value); > + cond_resched(); > } > > out: > -- > 2.19.0.605.g01d371f741-goog > > > -- > Dmitry >