diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/Locking | 4 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 20 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 11 |
3 files changed, 35 insertions, 0 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 06d443450f21..539ac9c78ccf 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -197,7 +197,9 @@ prototypes: int (*releasepage) (struct page *, int); void (*freepage)(struct page *); int (*direct_IO)(struct kiocb *, struct iov_iter *iter, loff_t offset); + bool (*isolate_page) (struct page *, isolate_mode_t); int (*migratepage)(struct address_space *, struct page *, struct page *); + void (*putback_page) (struct page *); int (*launder_page)(struct page *); int (*is_partially_uptodate)(struct page *, unsigned long, unsigned long); int (*error_remove_page)(struct address_space *, struct page *); @@ -221,7 +223,9 @@ invalidatepage: yes releasepage: yes freepage: yes direct_IO: +isolate_page: yes migratepage: yes (both) +putback_page: yes launder_page: yes is_partially_uptodate: yes error_remove_page: yes diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index d157847f769d..e7aa730b927b 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -138,6 +138,7 @@ Table 1-1: Process specific entries in /proc maps Memory maps to executables and library files (2.4) mem Memory held by this process root Link to the root directory of this process + reclaim Reclaim pages in this process stat Process status statm Process memory status information status Process status in human readable form @@ -499,6 +500,25 @@ current value: Any other value written to /proc/PID/clear_refs will have no effect. +The file /proc/PID/reclaim is used to reclaim pages in this process. +To reclaim file-backed pages, + > echo file > /proc/PID/reclaim + +To reclaim anonymous pages, + > echo anon > /proc/PID/reclaim + +To reclaim all pages, + > echo all > /proc/PID/reclaim + +Also, you can specify address range of process so part of address space +will be reclaimed. The format is following as + > echo addr size-byte > /proc/PID/reclaim + +NOTE: addr should be page-aligned. + +Below is example which try to reclaim 2M from 0x100000. + > echo 0x100000 2M > /proc/PID/reclaim + The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags using /proc/kpageflags and number of times a page is mapped using /proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.txt. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 8c6f07ad373a..66ddf1e8fe28 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -593,9 +593,14 @@ struct address_space_operations { int (*releasepage) (struct page *, int); void (*freepage)(struct page *); ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter, loff_t offset); + /* isolate a page for migration */ + bool (*isolate_page) (struct page *, isolate_mode_t); /* migrate the contents of a page to the specified target */ int (*migratepage) (struct page *, struct page *); + /* put migration-failed page back to right list */ + void (*putback_page) (struct page *); int (*launder_page) (struct page *); + int (*is_partially_uptodate) (struct page *, unsigned long, unsigned long); void (*is_dirty_writeback) (struct page *, bool *, bool *); @@ -748,6 +753,10 @@ 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, VM marks 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 that is signalling imminent failure) it will pass a new page @@ -755,6 +764,8 @@ struct address_space_operations { transfer any private data across and update any references that it has to the page. + putback_page: Called by the VM when isolated page's migration fails. + launder_page: Called before freeing a page - it writes back the dirty page. To prevent redirtying the page, it is kept locked during the whole operation. |