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McKenney" To: zhouzhouyi@gmail.com Cc: josh@joshtriplett.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] RCU: Adjust the comment of function rcu_is_watching Reply-To: paulmck@linux.ibm.com References: <5bbafe54.1c69fb81.954a9.deae@mx.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5bbafe54.1c69fb81.954a9.deae@mx.google.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18100904-0064-0000-0000-0000035C73E5 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009845; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000267; SDB=6.01099963; UDB=6.00569068; IPR=6.00880011; MB=3.00023672; MTD=3.00000008; XFM=3.00000015; UTC=2018-10-09 04:05:45 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18100904-0065-0000-0000-00003AEAC52C Message-Id: <20181009040541.GI2674@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-10-09_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=988 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810090042 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 08, 2018 at 06:50:41AM +0000, zhouzhouyi@gmail.com wrote: > From: Zhouyi Zhou > > Because RCU avoids interrupting idle CPUs, rcu_is_watching is used to > test whether or not it is currently legal to run RCU read-side > critical sections on this CPU. > > First sentence and last sentence of current comment for rcu_is_watching > have opposite meaning of what is expected. > > Signed-off-by: Zhouyi Zhou Good eyes! Applied and pushed, thank you! Thanx, Paul > --- > kernel/rcu/tree.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index 0b760c1..adb04ea 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -1010,12 +1010,12 @@ void rcu_irq_enter_irqson(void) > } > > /** > - * rcu_is_watching - see if RCU thinks that the current CPU is idle > + * rcu_is_watching - see if RCU thinks that the current CPU is not idle > * > * Return true if RCU is watching the running CPU, which means that this > * CPU can safely enter RCU read-side critical sections. In other words, > - * if the current CPU is in its idle loop and is neither in an interrupt > - * or NMI handler, return true. > + * if the current CPU is not in its idle loop or is in an interrupt or > + * NMI handler, return true. > */ > bool notrace rcu_is_watching(void) > { > -- > 2.1.4 >