search for: isolate_page

...e new functions together with its user after all, OK. > I will just resend to change the tile from "mm/compaction" to > "mm/migration". OK! >> Also I'm a bit uncomfortable how isolate_movable_page() blindly expects that >> page->mapping->a_ops->isolate_page exists for PageMovable() pages. >> What if it's a false positive on a PG_reclaim page? Can we rely on >> PG_reclaim always (and without races) implying PageLRU() so that we >> don't even attempt isolate_movable_page()? > > For now, we shouldn't have such a false...

...e new functions together with its user after all, OK. > I will just resend to change the tile from "mm/compaction" to > "mm/migration". OK! >> Also I'm a bit uncomfortable how isolate_movable_page() blindly expects that >> page->mapping->a_ops->isolate_page exists for PageMovable() pages. >> What if it's a false positive on a PG_reclaim page? Can we rely on >> PG_reclaim always (and without races) implying PageLRU() so that we >> don't even attempt isolate_movable_page()? > > For now, we shouldn't have such a false...

..., I see, so it's designed with page lock to handle the concurrent isolations etc. >> >> In http://marc.info/?l=linux-mm&m=143816716511904&w=2 Mel has warned >> about doing this in general under page_lock and suggested that each >> user handles concurrent calls to isolate_page() internally. Might be >> more generic that way, even if all current implementers will >> actually use the page lock. > > We need PG_lock for two reasons. > > Firstly, it guarantees page's flags operation(i.e., PG_movable, PG_isolated) > atomicity. Another thing is fo...

..., I see, so it's designed with page lock to handle the concurrent isolations etc. >> >> In http://marc.info/?l=linux-mm&m=143816716511904&w=2 Mel has warned >> about doing this in general under page_lock and suggested that each >> user handles concurrent calls to isolate_page() internally. Might be >> more generic that way, even if all current implementers will >> actually use the page lock. > > We need PG_lock for two reasons. > > Firstly, it guarantees page's flags operation(i.e., PG_movable, PG_isolated) > atomicity. Another thing is fo...

...igration to address_space_operations as well as some page flags. > > Basically, this patch supports two page-flags and two functions related > to page migration. The flag and page->mapping stability are protected > by PG_lock. > > PG_movable > PG_isolated > > bool (*isolate_page) (struct page *, isolate_mode_t); > void (*putback_page) (struct page *); > > Duty of subsystem want to make their pages as migratable are > as follows: > > 1. It should register address_space to page->mapping then mark > the page as PG_movable via __SetPageMovable. > &g...

...igration to address_space_operations as well as some page flags. > > Basically, this patch supports two page-flags and two functions related > to page migration. The flag and page->mapping stability are protected > by PG_lock. > > PG_movable > PG_isolated > > bool (*isolate_page) (struct page *, isolate_mode_t); > void (*putback_page) (struct page *); > > Duty of subsystem want to make their pages as migratable are > as follows: > > 1. It should register address_space to page->mapping then mark > the page as PG_movable via __SetPageMovable. > &g...

...3142f8ed7b 100644 > --- a/Documentation/filesystems/vfs.txt > +++ b/Documentation/filesystems/vfs.txt > @@ -752,12 +752,21 @@ struct address_space_operations { > and transfer data directly between the storage and the > application's address space. > > + isolate_page: Called by the VM when isolating a movable non-lru page. > + If page is successfully isolated, we should mark the page as > + PG_isolated via __SetPageIsolated. Patch 02 changelog suggests SetPageIsolated, so this is confusing. I guess the main point is that there might be parallel attempts...

...3142f8ed7b 100644 > --- a/Documentation/filesystems/vfs.txt > +++ b/Documentation/filesystems/vfs.txt > @@ -752,12 +752,21 @@ struct address_space_operations { > and transfer data directly between the storage and the > application's address space. > > + isolate_page: Called by the VM when isolating a movable non-lru page. > + If page is successfully isolated, we should mark the page as > + PG_isolated via __SetPageIsolated. Patch 02 changelog suggests SetPageIsolated, so this is confusing. I guess the main point is that there might be parallel attempts...

...well as some page flags. > > > >Basically, this patch supports two page-flags and two functions related > >to page migration. The flag and page->mapping stability are protected > >by PG_lock. > > > > PG_movable > > PG_isolated > > > > bool (*isolate_page) (struct page *, isolate_mode_t); > > void (*putback_page) (struct page *); > > > >Duty of subsystem want to make their pages as migratable are > >as follows: > > > >1. It should register address_space to page->mapping then mark > >the page as PG_movable...

...ation to address_space_operations as well as some page flags. > > Basically, this patch supports two page-flags and two functions related > to page migration. The flag and page->mapping stability are protected > by PG_lock. > > PG_movable > PG_isolated > > bool (*isolate_page) (struct page *, isolate_mode_t); > void (*putback_page) (struct page *); > > Duty of subsystem want to make their pages as migratable are > as follows: > > 1. It should register address_space to page->mapping then mark > the page as PG_movable via __SetPageMovable. >...

...ation to address_space_operations as well as some page flags. > > Basically, this patch supports two page-flags and two functions related > to page migration. The flag and page->mapping stability are protected > by PG_lock. > > PG_movable > PG_isolated > > bool (*isolate_page) (struct page *, isolate_mode_t); > void (*putback_page) (struct page *); > > Duty of subsystem want to make their pages as migratable are > as follows: > > 1. It should register address_space to page->mapping then mark > the page as PG_movable via __SetPageMovable. >...

...- a/Documentation/filesystems/vfs.txt > >+++ b/Documentation/filesystems/vfs.txt > >@@ -752,12 +752,21 @@ struct address_space_operations { > > and transfer data directly between the storage and the > > application's address space. > > > >+ isolate_page: Called by the VM when isolating a movable non-lru page. > >+ If page is successfully isolated, we should mark the page as > >+ PG_isolated via __SetPageIsolated. > > Patch 02 changelog suggests SetPageIsolated, so this is confusing. I > guess the main point is that there migh...

...pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate...

...pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate...

...pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate...

...pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate...

...t; Basically, this patch supports two page-flags and two functions related > > > to page migration. The flag and page->mapping stability are protected > > > by PG_lock. > > > > > > PG_movable > > > PG_isolated > > > > > > bool (*isolate_page) (struct page *, isolate_mode_t); > > > void (*putback_page) (struct page *); > > > > > > Duty of subsystem want to make their pages as migratable are > > > as follows: > > > > > > 1. It should register address_space to page->mapping then...

...t; Basically, this patch supports two page-flags and two functions related > > > to page migration. The flag and page->mapping stability are protected > > > by PG_lock. > > > > > > PG_movable > > > PG_isolated > > > > > > bool (*isolate_page) (struct page *, isolate_mode_t); > > > void (*putback_page) (struct page *); > > > > > > Duty of subsystem want to make their pages as migratable are > > > as follows: > > > > > > 1. It should register address_space to page->mapping then...

...tems/vfs.txt index 4c1b6c3b4bc8..d63142f8ed7b 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -752,12 +752,21 @@ struct address_space_operations { and transfer data directly between the storage and the application's address space. + isolate_page: Called by the VM when isolating a movable non-lru page. + If page is successfully isolated, we should mark the page as + PG_isolated via __SetPageIsolated. + migrate_page: This is used to compact the physical memory usage. If the VM wants to relocate a page (maybe off a memory card...

...pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate...