Subject: + mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch added to -mm tree To: iamjoonsoo.kim@xxxxxxx,dhillf@xxxxxxxxx,hughd@xxxxxxxxxx,mgorman@xxxxxxx,mingo@xxxxxxxxxx,n-horiguchi@xxxxxxxxxxxxx,riel@xxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Wed, 04 Dec 2013 14:16:45 -0800 The patch titled Subject: mm/rmap: extend rmap_walk_xxx() to cope with different cases has been added to the -mm tree. Its filename is mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Subject: mm/rmap: extend rmap_walk_xxx() to cope with different cases There are a lot of common parts in traversing functions, but there are also a little of uncommon parts in it. By assigning proper function pointer on each rmap_walker_control, we can handle these difference correctly. Following are differences we should handle. 1. difference of lock function in anon mapping case 2. nonlinear handling in file mapping case 3. prechecked condition: checking memcg in page_referenced(), checking VM_SHARE in page_mkclean() checking temporary vma in try_to_unmap() 4. exit condition: checking page_mapped() in try_to_unmap() So, in this patch, I introduce 4 function pointers to handle above differences. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Hillf Danton <dhillf@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/rmap.h | 15 +++++++++++++++ mm/ksm.c | 7 +++++++ mm/rmap.c | 37 +++++++++++++++++++++++++++++-------- 3 files changed, 51 insertions(+), 8 deletions(-) diff -puN include/linux/rmap.h~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases include/linux/rmap.h --- a/include/linux/rmap.h~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases +++ a/include/linux/rmap.h @@ -235,10 +235,25 @@ struct anon_vma *page_lock_anon_vma_read void page_unlock_anon_vma_read(struct anon_vma *anon_vma); int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma); +/* + * rmap_walk_control: To control rmap traversing for specific needs + * + * arg: passed to rmap_one() and invalid_vma() + * rmap_one: executed on each vma where page is mapped + * done: for checking traversing termination condition + * file_nonlinear: for handling file nonlinear mapping + * anon_lock: for getting anon_lock by optimized way rather than default + * invalid_vma: for skipping uninterested vma + */ struct rmap_walk_control { void *arg; int (*rmap_one)(struct page *page, struct vm_area_struct *vma, unsigned long addr, void *arg); + int (*done)(struct page *page); + int (*file_nonlinear)(struct page *, struct address_space *, + struct vm_area_struct *vma); + struct anon_vma *(*anon_lock)(struct page *page); + bool (*invalid_vma)(struct vm_area_struct *vma, void *arg); }; /* diff -puN mm/ksm.c~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases mm/ksm.c --- a/mm/ksm.c~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases +++ a/mm/ksm.c @@ -2032,12 +2032,19 @@ again: if ((rmap_item->mm == vma->vm_mm) == search_new_forks) continue; + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, rmap_item->address, rwc->arg); if (ret != SWAP_AGAIN) { anon_vma_unlock_read(anon_vma); goto out; } + if (rwc->done && rwc->done(page)) { + anon_vma_unlock_read(anon_vma); + goto out; + } } anon_vma_unlock_read(anon_vma); } diff -puN mm/rmap.c~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases mm/rmap.c --- a/mm/rmap.c~mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases +++ a/mm/rmap.c @@ -1680,10 +1680,14 @@ void __put_anon_vma(struct anon_vma *ano } #ifdef CONFIG_MIGRATION -static struct anon_vma *rmap_walk_anon_lock(struct page *page) +static struct anon_vma *rmap_walk_anon_lock(struct page *page, + struct rmap_walk_control *rwc) { struct anon_vma *anon_vma; + if (rwc->anon_lock) + return rwc->anon_lock(page); + /* * Note: remove_migration_ptes() cannot use page_lock_anon_vma_read() * because that depends on page_mapped(); but not all its usages @@ -1709,16 +1713,22 @@ static int rmap_walk_anon(struct page *p struct anon_vma_chain *avc; int ret = SWAP_AGAIN; - anon_vma = rmap_walk_anon_lock(page); + anon_vma = rmap_walk_anon_lock(page, rwc); if (!anon_vma) return ret; anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { struct vm_area_struct *vma = avc->vma; unsigned long address = vma_address(page, vma); + + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) break; + if (rwc->done && rwc->done(page)) + break; } anon_vma_unlock_read(anon_vma); return ret; @@ -1736,15 +1746,26 @@ static int rmap_walk_file(struct page *p mutex_lock(&mapping->i_mmap_mutex); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); + + if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) + continue; + ret = rwc->rmap_one(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) - break; + goto done; + if (rwc->done && rwc->done(page)) + goto done; } - /* - * No nonlinear handling: being always shared, nonlinear vmas - * never contain migration ptes. Decide what to do about this - * limitation to linear when we need rmap_walk() on nonlinear. - */ + + if (!rwc->file_nonlinear) + goto done; + + if (list_empty(&mapping->i_mmap_nonlinear)) + goto done; + + ret = rwc->file_nonlinear(page, mapping, vma); + +done: mutex_unlock(&mapping->i_mmap_mutex); return ret; } _ Patches currently in -mm which might be from iamjoonsoo.kim@xxxxxxx are mm-rmap-recompute-pgoff-for-huge-page.patch mm-rmap-factor-nonlinear-handling-out-of-try_to_unmap_file.patch mm-rmap-factor-lock-function-out-of-rmap_walk_anon.patch mm-rmap-make-rmap_walk-to-get-the-rmap_walk_control-argument.patch mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch mm-rmap-use-rmap_walk-in-try_to_unmap.patch mm-rmap-use-rmap_walk-in-try_to_munlock.patch mm-rmap-use-rmap_walk-in-page_referenced.patch mm-rmap-use-rmap_walk-in-page_mkclean.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html