From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933475AbeE2MDJ (ORCPT ); Tue, 29 May 2018 08:03:09 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48120 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933357AbeE2MDG (ORCPT ); Tue, 29 May 2018 08:03:06 -0400 Date: Tue, 29 May 2018 05:04:43 -0700 From: "Paul E. McKenney" To: "Rafael J. Wysocki" Cc: Sebastian Andrzej Siewior , Linux PM , Linux Kernel Mailing List , "Rafael J. Wysocki" , Viresh Kumar , Thomas Gleixner Subject: Re: [PATCH 1/2] kernel/SRCU: provide a static initializer Reply-To: paulmck@linux.vnet.ibm.com References: <20180525101958.13277-1-bigeasy@linutronix.de> <20180525101958.13277-2-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18052912-0056-0000-0000-00000459230A X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009096; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000264; SDB=6.01039349; UDB=6.00530875; IPR=6.00818478; MB=3.00021357; MTD=3.00000008; XFM=3.00000015; UTC=2018-05-29 12:03:02 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18052912-0057-0000-0000-0000089D4736 Message-Id: <20180529120443.GE3803@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-05-29_04:,, 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 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1805290138 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 29, 2018 at 10:09:51AM +0200, Rafael J. Wysocki wrote: > On Fri, May 25, 2018 at 12:19 PM, Sebastian Andrzej Siewior > wrote: > > There are macros for static initializer for the three out of four > > possible notifier types, that are: > > ATOMIC_NOTIFIER_HEAD() > > BLOCKING_NOTIFIER_HEAD() > > RAW_NOTIFIER_HEAD() > > > > This patch provides a static initilizer for the forth type to make it > > complete. > > > > Cc: "Paul E. McKenney" > > Signed-off-by: Sebastian Andrzej Siewior > > I cannot apply this without an ACK from Paul. I have both queued, but if you would prefer to take them, then for the SRCU piece: Tested-by: Paul E. McKenney Reviewed-by: Paul E. McKenney Thanx, Paul > > --- > > include/linux/notifier.h | 34 +++++++++++++++++++++++++++++----- > > include/linux/srcutiny.h | 6 +++--- > > include/linux/srcutree.h | 6 +++--- > > 3 files changed, 35 insertions(+), 11 deletions(-) > > > > diff --git a/include/linux/notifier.h b/include/linux/notifier.h > > index 6d731110e0db..f35c7bf76143 100644 > > --- a/include/linux/notifier.h > > +++ b/include/linux/notifier.h > > @@ -43,9 +43,7 @@ > > * in srcu_notifier_call_chain(): no cache bounces and no memory barriers. > > * As compensation, srcu_notifier_chain_unregister() is rather expensive. > > * SRCU notifier chains should be used when the chain will be called very > > - * often but notifier_blocks will seldom be removed. Also, SRCU notifier > > - * chains are slightly more difficult to use because they require special > > - * runtime initialization. > > + * often but notifier_blocks will seldom be removed. > > */ > > > > struct notifier_block; > > @@ -91,7 +89,7 @@ struct srcu_notifier_head { > > (name)->head = NULL; \ > > } while (0) > > > > -/* srcu_notifier_heads must be initialized and cleaned up dynamically */ > > +/* srcu_notifier_heads must be cleaned up dynamically */ > > extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); > > #define srcu_cleanup_notifier_head(name) \ > > cleanup_srcu_struct(&(name)->srcu); > > @@ -104,7 +102,13 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); > > .head = NULL } > > #define RAW_NOTIFIER_INIT(name) { \ > > .head = NULL } > > -/* srcu_notifier_heads cannot be initialized statically */ > > + > > +#define SRCU_NOTIFIER_INIT(name, pcpu) \ > > + { \ > > + .mutex = __MUTEX_INITIALIZER(name.mutex), \ > > + .head = NULL, \ > > + .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu), \ > > + } > > > > #define ATOMIC_NOTIFIER_HEAD(name) \ > > struct atomic_notifier_head name = \ > > @@ -116,6 +120,26 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); > > struct raw_notifier_head name = \ > > RAW_NOTIFIER_INIT(name) > > > > +#ifdef CONFIG_TREE_SRCU > > +#define _SRCU_NOTIFIER_HEAD(name, mod) \ > > + static DEFINE_PER_CPU(struct srcu_data, \ > > + name##_head_srcu_data); \ > > + mod struct srcu_notifier_head name = \ > > + SRCU_NOTIFIER_INIT(name, name##_head_srcu_data) > > + > > +#else > > +#define _SRCU_NOTIFIER_HEAD(name, mod) \ > > + mod struct srcu_notifier_head name = \ > > + SRCU_NOTIFIER_INIT(name, name) > > + > > +#endif > > + > > +#define SRCU_NOTIFIER_HEAD(name) \ > > + _SRCU_NOTIFIER_HEAD(name, /* not static */) > > + > > +#define SRCU_NOTIFIER_HEAD_STATIC(name) \ > > + _SRCU_NOTIFIER_HEAD(name, static) > > + > > #ifdef __KERNEL__ > > > > extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh, > > diff --git a/include/linux/srcutiny.h b/include/linux/srcutiny.h > > index 261471f407a5..f41d2fb09f87 100644 > > --- a/include/linux/srcutiny.h > > +++ b/include/linux/srcutiny.h > > @@ -43,7 +43,7 @@ struct srcu_struct { > > > > void srcu_drive_gp(struct work_struct *wp); > > > > -#define __SRCU_STRUCT_INIT(name) \ > > +#define __SRCU_STRUCT_INIT(name, __ignored) \ > > { \ > > .srcu_wq = __SWAIT_QUEUE_HEAD_INITIALIZER(name.srcu_wq), \ > > .srcu_cb_tail = &name.srcu_cb_head, \ > > @@ -56,9 +56,9 @@ void srcu_drive_gp(struct work_struct *wp); > > * Tree SRCU, which needs some per-CPU data. > > */ > > #define DEFINE_SRCU(name) \ > > - struct srcu_struct name = __SRCU_STRUCT_INIT(name) > > + struct srcu_struct name = __SRCU_STRUCT_INIT(name, name) > > #define DEFINE_STATIC_SRCU(name) \ > > - static struct srcu_struct name = __SRCU_STRUCT_INIT(name) > > + static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name) > > > > void synchronize_srcu(struct srcu_struct *sp); > > > > diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h > > index 4eda108abee0..745d4ca4dd50 100644 > > --- a/include/linux/srcutree.h > > +++ b/include/linux/srcutree.h > > @@ -104,9 +104,9 @@ struct srcu_struct { > > #define SRCU_STATE_SCAN1 1 > > #define SRCU_STATE_SCAN2 2 > > > > -#define __SRCU_STRUCT_INIT(name) \ > > +#define __SRCU_STRUCT_INIT(name, pcpu_name) \ > > { \ > > - .sda = &name##_srcu_data, \ > > + .sda = &pcpu_name, \ > > .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ > > .srcu_gp_seq_needed = 0 - 1, \ > > __SRCU_DEP_MAP_INIT(name) \ > > @@ -133,7 +133,7 @@ struct srcu_struct { > > */ > > #define __DEFINE_SRCU(name, is_static) \ > > static DEFINE_PER_CPU(struct srcu_data, name##_srcu_data);\ > > - is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name) > > + is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_data) > > #define DEFINE_SRCU(name) __DEFINE_SRCU(name, /* not static */) > > #define DEFINE_STATIC_SRCU(name) __DEFINE_SRCU(name, static) > > > > -- > > 2.17.0 > > >