Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread NeilBrown
On Wed, 6 Nov 2013 15:22:36 -0500 Chris Mason wrote: > > Yup - that should actually be safe for all the existing bio_clone() users > > actually, I audited all of them - because normally you're not going to > > complete > > the original bio until the clone finishes. > > I'd say we need an ack

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 04:25:45PM -0500, Chris Mason wrote: > Quoting Kent Overstreet (2013-11-06 15:57:34) > > On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: > > > Quoting Kent Overstreet (2013-11-06 15:02:22) > > [ ... nods, thanks! ... ] > > > OTOH - with regards to just the

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-06 15:57:34) > On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: > > Quoting Kent Overstreet (2013-11-06 15:02:22) [ ... nods, thanks! ... ] > OTOH - with regards to just the ordering requirements, the more I look at > various code the less accidental

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: > Quoting Kent Overstreet (2013-11-06 15:02:22) > > Yup - that should actually be safe for all the existing bio_clone() users > > actually, I audited all of them - because normally you're not going to > > complete > > the original bio

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Mike Snitzer (2013-11-06 15:36:40) > On Wed, Nov 06 2013 at 3:22pm -0500, > Chris Mason wrote: > > > Quoting Kent Overstreet (2013-11-06 15:02:22) > > > On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: > > > > > > > > I think the concept of bio ownership is still much too

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 03:31:02PM -0500, Mike Snitzer wrote: > Hey Kent, > > Digging a bit in the LKML archive I think this patch is in response to > this thread: https://lkml.org/lkml/2013/11/6/27 That thread I saw, Jens told me there was another one though > Might be good to give context for

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Mike Snitzer
On Wed, Nov 06 2013 at 3:22pm -0500, Chris Mason wrote: > Quoting Kent Overstreet (2013-11-06 15:02:22) > > On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: > > > > > > I think the concept of bio ownership is still much too weak, at least > > > for established users like MD and DM.

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Mike Snitzer
Hey Kent, Digging a bit in the LKML archive I think this patch is in response to this thread: https://lkml.org/lkml/2013/11/6/27 Might be good to give context for which reported problem(s) are being fixed by this patch. On Tue, Nov 05 2013 at 10:48pm -0500, Kent Overstreet wrote: > This patch

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-06 15:02:22) > On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: > > Quoting Kent Overstreet (2013-11-05 22:48:41) > > > This patch reverts the default behaviour introduced by > > > 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: > Quoting Kent Overstreet (2013-11-05 22:48:41) > > This patch reverts the default behaviour introduced by > > 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger > > shares the source bio's biovec, cloning the

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-05 22:48:41) > This patch reverts the default behaviour introduced by > 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger > shares the source bio's biovec, cloning the biovec is once again the > default. > > Instead, we add a new

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Olof Johansson
On Tue, Nov 5, 2013 at 9:07 PM, Kent Overstreet wrote: > On Tue, Nov 05, 2013 at 09:02:19PM -0800, Olof Johansson wrote: >> Hi, >> >> On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet wrote: >> >> > Chris, Olaf, can you two in particular test this? I have tested the bounce >> > buffer code (and

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Olof Johansson
On Tue, Nov 5, 2013 at 9:07 PM, Kent Overstreet k...@daterainc.com wrote: On Tue, Nov 05, 2013 at 09:02:19PM -0800, Olof Johansson wrote: Hi, On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet k...@daterainc.com wrote: Chris, Olaf, can you two in particular test this? I have tested the bounce

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-05 22:48:41) This patch reverts the default behaviour introduced by 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger shares the source bio's biovec, cloning the biovec is once again the default. Instead, we add a new

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-05 22:48:41) This patch reverts the default behaviour introduced by 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger shares the source bio's biovec, cloning the biovec is

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-06 15:02:22) On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-05 22:48:41) This patch reverts the default behaviour introduced by 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Mike Snitzer
Hey Kent, Digging a bit in the LKML archive I think this patch is in response to this thread: https://lkml.org/lkml/2013/11/6/27 Might be good to give context for which reported problem(s) are being fixed by this patch. On Tue, Nov 05 2013 at 10:48pm -0500, Kent Overstreet k...@daterainc.com

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Mike Snitzer
On Wed, Nov 06 2013 at 3:22pm -0500, Chris Mason chris.ma...@fusionio.com wrote: Quoting Kent Overstreet (2013-11-06 15:02:22) On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: I think the concept of bio ownership is still much too weak, at least for established users

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 03:31:02PM -0500, Mike Snitzer wrote: Hey Kent, Digging a bit in the LKML archive I think this patch is in response to this thread: https://lkml.org/lkml/2013/11/6/27 That thread I saw, Jens told me there was another one though Might be good to give context for

Re: block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Mike Snitzer (2013-11-06 15:36:40) On Wed, Nov 06 2013 at 3:22pm -0500, Chris Mason chris.ma...@fusionio.com wrote: Quoting Kent Overstreet (2013-11-06 15:02:22) On Wed, Nov 06, 2013 at 11:11:30AM -0500, Chris Mason wrote: I think the concept of bio ownership is still

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-06 15:02:22) Yup - that should actually be safe for all the existing bio_clone() users actually, I audited all of them - because normally you're not going to complete the original bio until the

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Chris Mason
Quoting Kent Overstreet (2013-11-06 15:57:34) On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-06 15:02:22) [ ... nods, thanks! ... ] OTOH - with regards to just the ordering requirements, the more I look at various code the less accidental the

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread Kent Overstreet
On Wed, Nov 06, 2013 at 04:25:45PM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-06 15:57:34) On Wed, Nov 06, 2013 at 03:22:36PM -0500, Chris Mason wrote: Quoting Kent Overstreet (2013-11-06 15:02:22) [ ... nods, thanks! ... ] OTOH - with regards to just the ordering

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-06 Thread NeilBrown
On Wed, 6 Nov 2013 15:22:36 -0500 Chris Mason chris.ma...@fusionio.com wrote: Yup - that should actually be safe for all the existing bio_clone() users actually, I audited all of them - because normally you're not going to complete the original bio until the clone finishes. I'd say

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Kent Overstreet
On Tue, Nov 05, 2013 at 09:02:19PM -0800, Olof Johansson wrote: > Hi, > > On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet wrote: > > > Chris, Olaf, can you two in particular test this? I have tested the bounce > > buffer code (and bcache), but Jens told me today there was an md bug that I > >

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Olof Johansson
Hi, On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet wrote: > Chris, Olaf, can you two in particular test this? I have tested the bounce > buffer code (and bcache), but Jens told me today there was an md bug that I > _still_ can't find any emails about so I'm not sure what to test for that.

[PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Kent Overstreet
This patch reverts the default behaviour introduced by 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger shares the source bio's biovec, cloning the biovec is once again the default. Instead, we add a new bio_clone_biovec_fast(), which creates a clone that shares the

[PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Kent Overstreet
This patch reverts the default behaviour introduced by 9fc6286f347d00528adcdcf12396d220f47492ed - bio_clone_biovec() no clonger shares the source bio's biovec, cloning the biovec is once again the default. Instead, we add a new bio_clone_biovec_fast(), which creates a clone that shares the

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Olof Johansson
Hi, On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet k...@daterainc.com wrote: Chris, Olaf, can you two in particular test this? I have tested the bounce buffer code (and bcache), but Jens told me today there was an md bug that I _still_ can't find any emails about so I'm not sure what to test

Re: [PATCH] block: Revert bio_clone() default behaviour

2013-11-05 Thread Kent Overstreet
On Tue, Nov 05, 2013 at 09:02:19PM -0800, Olof Johansson wrote: Hi, On Tue, Nov 5, 2013 at 7:48 PM, Kent Overstreet k...@daterainc.com wrote: Chris, Olaf, can you two in particular test this? I have tested the bounce buffer code (and bcache), but Jens told me today there was an md bug