From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: NeilBrown Date: Fri, 01 Apr 2016 11:34:56 +1100 Subject: Re: [PATCH 12/12] dax: New fault locking In-Reply-To: <20160331085449.GB11041@quack.suse.cz> References: <1457637535-21633-1-git-send-email-jack@suse.cz> <1457637535-21633-13-git-send-email-jack@suse.cz> <87h9gdj3dt.fsf@notabene.neil.brown.name> <87egbbh1cr.fsf@notabene.neil.brown.name> <20160318141618.GF7152@quack.suse.cz> <20160318153919.GG7152@quack.suse.cz> <87h9fycj71.fsf@notabene.neil.brown.name> <20160323110011.GD4512@quack.suse.cz> <87oa9vs2hb.fsf@notabene.neil.brown.name> <20160331085449.GB11041@quack.suse.cz> Message-ID: <87oa9uqi8f.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-fsdevel-owner@vger.kernel.org To: Jan Kara Cc: linux-fsdevel@vger.kernel.org, "Wilcox, Matthew R" , Ross Zwisler , Dan Williams , linux-nvdimm@lists.01.org List-ID: --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Thu, Mar 31 2016, Jan Kara wrote: > On Thu 31-03-16 15:20:00, NeilBrown wrote: >> On Wed, Mar 23 2016, Jan Kara wrote: >>=20 >> > But how does this really help? If lookup_unlocked_mapping_entry() finds >> > there is no entry (and it was there before), the process deleting the = entry >> > (or replacing it with something else) is responsible for waking up >> > everybody. >>=20 >> "everybody" - yes. But it doesn't wake everybody does it? It just >> wakes one. >>=20 >> + __wake_up(wq, TASK_NORMAL, 1, &key); >> ^one! >>=20 >> Or am I misunderstanding how exclusive waiting works? > > Ah, OK. I have already fixed that in my local version of the patches so > that we wake-up everybody after deleting the entry but forgot to tell you. > So I have there now: > > __wake_up(wq, TASK_NORMAL, 0, &key); "0" meaning "MAX_INT+1" (or something). I didn't realize you could do that, but it makes perfect sense. > > Are you OK with the code now? Certainly less unhappy. Assume that I am OK but I'll try to have another look when you post again and make sure any lingering doubts are gone. Thanks, NeilBrown > > Honza > --=20 > Jan Kara > SUSE Labs, CR --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJW/cIwAAoJEDnsnt1WYoG5kGUQALop5KpnCN+YoMcvSfZpcO4n Ss3k8U/fk16Yw+W0vrcFcbazFcPBCdCHOAYXNQnLw2IqfE00HdBe/IiSo5ndcFTG HV4AU4PeZw0bB96k5p0aHsnnIkAcv95OQslcC2kcbnPNx8UTleQG6cqLb6QQuxVT bGeHPwV9id31Ks3MGqJncqebFw0LipJ+VIl7bLGA4yprYYoxnYJW/QaTcf6Sa7VX /kxZ5rfSYMX9uKjuvE7QACVUV7Z0m5Yci6b/YX/wQTOopckHozFz50qWekcNsoyt w8WhFvyNdfiCFLjBNq9aKrHzlkqs0HHWeod3b7cR3HiOqS5of+tO9rX5bq2/8dVu mYLO2Z6lKPhIw2BfrM0kt2xuvsSVdFizJccVaj0BOKZvgA/Fyt3h6cd19s07Vhrv Q0FAduYuiRCNCZsG84RFwhFwSAoCf973CDK7OWdhLYoTh5pWD9w85rbLsoPOllm7 naH0m6JDytWTCXFLYwPExl37u1dfLCDWfgBngA0vNhtHztTKGGpZkI+nPD/qYYN9 0IIT0MZoCYMNKHgnjJu9CrR6Hmbp89RTj34s3WozCD4/cD+bzwKtfutEKw4HXV4B OV1HKY1LMOPVZOyIYa81tDIQjiL37FBbFpo3FG57laROutOHtk0R7nuBa7RGaMmr xktDpB8QB5uh+DyvKZp1 =tDMz -----END PGP SIGNATURE----- --=-=-=-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:50502 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750720AbcDAAfH (ORCPT ); Thu, 31 Mar 2016 20:35:07 -0400 From: NeilBrown To: Jan Kara Date: Fri, 01 Apr 2016 11:34:56 +1100 Cc: Jan Kara , linux-fsdevel@vger.kernel.org, "Wilcox\, Matthew R" , Ross Zwisler , Dan Williams , linux-nvdimm@lists.01.org Subject: Re: [PATCH 12/12] dax: New fault locking In-Reply-To: <20160331085449.GB11041@quack.suse.cz> References: <1457637535-21633-1-git-send-email-jack@suse.cz> <1457637535-21633-13-git-send-email-jack@suse.cz> <87h9gdj3dt.fsf@notabene.neil.brown.name> <87egbbh1cr.fsf@notabene.neil.brown.name> <20160318141618.GF7152@quack.suse.cz> <20160318153919.GG7152@quack.suse.cz> <87h9fycj71.fsf@notabene.neil.brown.name> <20160323110011.GD4512@quack.suse.cz> <87oa9vs2hb.fsf@notabene.neil.brown.name> <20160331085449.GB11041@quack.suse.cz> Message-ID: <87oa9uqi8f.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-fsdevel-owner@vger.kernel.org List-ID: --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Thu, Mar 31 2016, Jan Kara wrote: > On Thu 31-03-16 15:20:00, NeilBrown wrote: >> On Wed, Mar 23 2016, Jan Kara wrote: >>=20 >> > But how does this really help? If lookup_unlocked_mapping_entry() finds >> > there is no entry (and it was there before), the process deleting the = entry >> > (or replacing it with something else) is responsible for waking up >> > everybody. >>=20 >> "everybody" - yes. But it doesn't wake everybody does it? It just >> wakes one. >>=20 >> + __wake_up(wq, TASK_NORMAL, 1, &key); >> ^one! >>=20 >> Or am I misunderstanding how exclusive waiting works? > > Ah, OK. I have already fixed that in my local version of the patches so > that we wake-up everybody after deleting the entry but forgot to tell you. > So I have there now: > > __wake_up(wq, TASK_NORMAL, 0, &key); "0" meaning "MAX_INT+1" (or something). I didn't realize you could do that, but it makes perfect sense. > > Are you OK with the code now? Certainly less unhappy. Assume that I am OK but I'll try to have another look when you post again and make sure any lingering doubts are gone. Thanks, NeilBrown > > Honza > --=20 > Jan Kara > SUSE Labs, CR --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJW/cIwAAoJEDnsnt1WYoG5kGUQALop5KpnCN+YoMcvSfZpcO4n Ss3k8U/fk16Yw+W0vrcFcbazFcPBCdCHOAYXNQnLw2IqfE00HdBe/IiSo5ndcFTG HV4AU4PeZw0bB96k5p0aHsnnIkAcv95OQslcC2kcbnPNx8UTleQG6cqLb6QQuxVT bGeHPwV9id31Ks3MGqJncqebFw0LipJ+VIl7bLGA4yprYYoxnYJW/QaTcf6Sa7VX /kxZ5rfSYMX9uKjuvE7QACVUV7Z0m5Yci6b/YX/wQTOopckHozFz50qWekcNsoyt w8WhFvyNdfiCFLjBNq9aKrHzlkqs0HHWeod3b7cR3HiOqS5of+tO9rX5bq2/8dVu mYLO2Z6lKPhIw2BfrM0kt2xuvsSVdFizJccVaj0BOKZvgA/Fyt3h6cd19s07Vhrv Q0FAduYuiRCNCZsG84RFwhFwSAoCf973CDK7OWdhLYoTh5pWD9w85rbLsoPOllm7 naH0m6JDytWTCXFLYwPExl37u1dfLCDWfgBngA0vNhtHztTKGGpZkI+nPD/qYYN9 0IIT0MZoCYMNKHgnjJu9CrR6Hmbp89RTj34s3WozCD4/cD+bzwKtfutEKw4HXV4B OV1HKY1LMOPVZOyIYa81tDIQjiL37FBbFpo3FG57laROutOHtk0R7nuBa7RGaMmr xktDpB8QB5uh+DyvKZp1 =tDMz -----END PGP SIGNATURE----- --=-=-=--