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McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" , Dennis Zhou , Tejun Heo , Christoph Lameter Subject: [PATCH tip/core/rcu 34/41] percpu-rwsem: Replace synchronize_sched() with synchronize_rcu() Date: Sun, 11 Nov 2018 11:44:03 -0800 X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181111194104.GA4787@linux.ibm.com> References: <20181111194104.GA4787@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18111119-0068-0000-0000-0000035E4831 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010028; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000270; SDB=6.01116019; UDB=6.00578732; IPR=6.00896120; MB=3.00024114; MTD=3.00000008; XFM=3.00000015; UTC=2018-11-11 19:44:19 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18111119-0069-0000-0000-000046644C6E Message-Id: <20181111194410.6368-34-paulmck@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-11-11_13:,, 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=991 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1811110188 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that synchronize_rcu() waits for preempt-disable regions of code as well as RCU read-side critical sections, synchronize_sched() can be replaced by synchronize_rcu(). This commit therefore makes this change, even though it is but a comment. Signed-off-by: Paul E. McKenney Cc: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter --- include/linux/percpu-rwsem.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/percpu-rwsem.h b/include/linux/percpu-rwsem.h index 79b99d653e03..71b75643c432 100644 --- a/include/linux/percpu-rwsem.h +++ b/include/linux/percpu-rwsem.h @@ -41,7 +41,7 @@ static inline void percpu_down_read_preempt_disable(struct percpu_rw_semaphore * * cannot both change sem->state from readers_fast and start checking * counters while we are here. So if we see !sem->state, we know that * the writer won't be checking until we're past the preempt_enable() - * and that one the synchronize_sched() is done, the writer will see + * and that once the synchronize_rcu() is done, the writer will see * anything we did within this RCU-sched read-size critical section. */ __this_cpu_inc(*sem->read_count); -- 2.17.1