Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 10:39:13, Lorenzo Stoakes wrote: > On Wed, Oct 26, 2016 at 11:15:43AM +0200, Michal Hocko wrote: > > On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > > > The holdout for unexporting __get_user_pages_unlocked() is its invocation > > > in > > > mm/process_vm_access.c:

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 10:39:13, Lorenzo Stoakes wrote: > On Wed, Oct 26, 2016 at 11:15:43AM +0200, Michal Hocko wrote: > > On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > > > The holdout for unexporting __get_user_pages_unlocked() is its invocation > > > in > > > mm/process_vm_access.c:

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Lorenzo Stoakes
On Wed, Oct 26, 2016 at 11:15:43AM +0200, Michal Hocko wrote: > On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > > The holdout for unexporting __get_user_pages_unlocked() is its invocation in > > mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely > > _does_ > > seem to

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Lorenzo Stoakes
On Wed, Oct 26, 2016 at 11:15:43AM +0200, Michal Hocko wrote: > On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > > The holdout for unexporting __get_user_pages_unlocked() is its invocation in > > mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely > > _does_ > > seem to

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > The holdout for unexporting __get_user_pages_unlocked() is its invocation in > mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely _does_ > seem to invoke VM_FAULT_RETRY behaviour which get_user_pages_remote() will not > trigger

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 00:46:31, Lorenzo Stoakes wrote: > The holdout for unexporting __get_user_pages_unlocked() is its invocation in > mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely _does_ > seem to invoke VM_FAULT_RETRY behaviour which get_user_pages_remote() will not > trigger

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 00:36:09, Lorenzo Stoakes wrote: > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > get_user_pages_unlocked() since we can now pass gup_flags. > > In async_pf_execute() we need to pass different tsk, mm arguments so > get_user_pages_remote() is the

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 00:36:09, Lorenzo Stoakes wrote: > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > get_user_pages_unlocked() since we can now pass gup_flags. > > In async_pf_execute() we need to pass different tsk, mm arguments so > get_user_pages_remote() is the

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 08:59:52, Lorenzo Stoakes wrote: > On Wed, Oct 26, 2016 at 12:36:09AM +0100, Lorenzo Stoakes wrote: > > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > > get_user_pages_unlocked() since we can now pass gup_flags. > > > > In async_pf_execute() we need

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Michal Hocko
On Wed 26-10-16 08:59:52, Lorenzo Stoakes wrote: > On Wed, Oct 26, 2016 at 12:36:09AM +0100, Lorenzo Stoakes wrote: > > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > > get_user_pages_unlocked() since we can now pass gup_flags. > > > > In async_pf_execute() we need

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Lorenzo Stoakes
On Wed, Oct 26, 2016 at 12:36:09AM +0100, Lorenzo Stoakes wrote: > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > get_user_pages_unlocked() since we can now pass gup_flags. > > In async_pf_execute() we need to pass different tsk, mm arguments so >

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-26 Thread Lorenzo Stoakes
On Wed, Oct 26, 2016 at 12:36:09AM +0100, Lorenzo Stoakes wrote: > In hva_to_pfn_slow() we are able to replace __get_user_pages_unlocked() with > get_user_pages_unlocked() since we can now pass gup_flags. > > In async_pf_execute() we need to pass different tsk, mm arguments so >

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-25 Thread Lorenzo Stoakes
The holdout for unexporting __get_user_pages_unlocked() is its invocation in mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely _does_ seem to invoke VM_FAULT_RETRY behaviour which get_user_pages_remote() will not trigger if we were to replace it with the latter. I'm not sure

Re: [PATCH] mm: remove unnecessary __get_user_pages_unlocked() calls

2016-10-25 Thread Lorenzo Stoakes
The holdout for unexporting __get_user_pages_unlocked() is its invocation in mm/process_vm_access.c: process_vm_rw_single_vec(), as this definitely _does_ seem to invoke VM_FAULT_RETRY behaviour which get_user_pages_remote() will not trigger if we were to replace it with the latter. I'm not sure