[ipc] 5769cf63: LTP semget02 TFAILs

[ipc] 5769cf63: LTP semget02 TFAILs

[Fengguang Wu]

Hi Davidlohr,

We noticed LTP test failures

        ltp.msgget02.1.TFAIL
        ltp.semget02.2.TFAIL
        ltp.semget02.3.TFAIL

and the first bad commit is

commit 5769cf6355d87f63906b3e51887eff7017c39217
Author:     Davidlohr Bueso <davidlohr@hp.com>
AuthorDate: Wed Jan 15 16:56:01 2014 +1100
Commit:     Stephen Rothwell <sfr@canb.auug.org.au>
CommitDate: Wed Jan 15 16:56:01 2014 +1100

    ipc: share ids rwsem when possible in ipcget_public
    
    ...  and rewrite the function.  For scenarios where the key is found and
    we end up just doing different routinary checks, we can downgrade the
    ids->rwsem and share it among concurrent readers.  These checks include
    the following, which are all safe to share the lock:
    
    ops->more_checks() >>  sem_more_checks(), shm_more_checks()
    ipc_check_perms()  >>  ipcperms(),ops->associate() >> [lsm]_[ipctype]_associate()
    
    Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
    Cc: Aswin Chandramouleeswaran <aswin@hp.com>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Manfred Spraul <manfred@colorfullife.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

 ipc/util.c | 60 +++++++++++++++++++++++++++++++++---------------------------
 1 file changed, 33 insertions(+), 27 deletions(-)

Thanks,
Fengguang

Re: [ipc] 5769cf63: LTP semget02 TFAILs

[Stephen Rothwell]

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[ Just adding Andrew to the cc list ]

On Fri, 17 Jan 2014 18:24:28 +0800 Fengguang Wu <fengguang.wu@intel.com> wrote:
>
> Hi Davidlohr,
> 
> We noticed LTP test failures
> 
>         ltp.msgget02.1.TFAIL
>         ltp.semget02.2.TFAIL
>         ltp.semget02.3.TFAIL
> 
> and the first bad commit is
> 
> commit 5769cf6355d87f63906b3e51887eff7017c39217
> Author:     Davidlohr Bueso <davidlohr@hp.com>
> AuthorDate: Wed Jan 15 16:56:01 2014 +1100
> Commit:     Stephen Rothwell <sfr@canb.auug.org.au>
> CommitDate: Wed Jan 15 16:56:01 2014 +1100
> 
>     ipc: share ids rwsem when possible in ipcget_public
>     
>     ...  and rewrite the function.  For scenarios where the key is found and
>     we end up just doing different routinary checks, we can downgrade the
>     ids->rwsem and share it among concurrent readers.  These checks include
>     the following, which are all safe to share the lock:
>     
>     ops->more_checks() >>  sem_more_checks(), shm_more_checks()
>     ipc_check_perms()  >>  ipcperms(),ops->associate() >> [lsm]_[ipctype]_associate()
>     
>     Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
>     Cc: Aswin Chandramouleeswaran <aswin@hp.com>
>     Cc: Rik van Riel <riel@redhat.com>
>     Cc: Manfred Spraul <manfred@colorfullife.com>
>     Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> 
>  ipc/util.c | 60 +++++++++++++++++++++++++++++++++---------------------------
>  1 file changed, 33 insertions(+), 27 deletions(-)
> 
> Thanks,
> Fengguang
> 


-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au

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Re: [ipc] 5769cf63: LTP semget02 TFAILs

[Andrew Morton]

On Fri, 17 Jan 2014 18:24:28 +0800 Fengguang Wu <fengguang.wu@intel.com> wrote:

> Hi Davidlohr,
> 
> We noticed LTP test failures
> 
>         ltp.msgget02.1.TFAIL
>         ltp.semget02.2.TFAIL
>         ltp.semget02.3.TFAIL
> 
> and the first bad commit is
> 
> commit 5769cf6355d87f63906b3e51887eff7017c39217
> Author:     Davidlohr Bueso <davidlohr@hp.com>
> AuthorDate: Wed Jan 15 16:56:01 2014 +1100
> Commit:     Stephen Rothwell <sfr@canb.auug.org.au>
> CommitDate: Wed Jan 15 16:56:01 2014 +1100
> 
>     ipc: share ids rwsem when possible in ipcget_public
>     

Thanks (a lot). I'll disable that patch for now.