It seems we don't have compound page on FS/IO path currently. Use PF_NO_COMPOUND to catch if we have.
The odd exception is PG_dirty: sound uses compound pages and maps them with PTEs. PF_NO_COMPOUND triggers VM_BUG_ON() in set_page_dirty() on handling shared fault. Let's use PF_HEAD for PG_dirty. Signed-off-by: Kirill A. Shutemov <[email protected]> --- include/linux/page-flags.h | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 26102813f0ac..63db7483c264 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -245,16 +245,16 @@ static inline int __TestClearPage##uname(struct page *page) { return 0; } TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname) __PAGEFLAG(Locked, locked, PF_NO_TAIL) -PAGEFLAG(Error, error, PF_ANY) TESTCLEARFLAG(Error, error, PF_ANY) +PAGEFLAG(Error, error, PF_NO_COMPOUND) TESTCLEARFLAG(Error, error, PF_NO_COMPOUND) PAGEFLAG(Referenced, referenced, PF_ANY) TESTCLEARFLAG(Referenced, referenced, PF_ANY) __SETPAGEFLAG(Referenced, referenced, PF_ANY) -PAGEFLAG(Dirty, dirty, PF_ANY) TESTSCFLAG(Dirty, dirty, PF_ANY) - __CLEARPAGEFLAG(Dirty, dirty, PF_ANY) +PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) + __CLEARPAGEFLAG(Dirty, dirty, PF_HEAD) PAGEFLAG(LRU, lru, PF_ANY) __CLEARPAGEFLAG(LRU, lru, PF_ANY) PAGEFLAG(Active, active, PF_ANY) __CLEARPAGEFLAG(Active, active, PF_ANY) TESTCLEARFLAG(Active, active, PF_ANY) __PAGEFLAG(Slab, slab, PF_ANY) -PAGEFLAG(Checked, checked, PF_ANY) /* Used by some filesystems */ +PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ PAGEFLAG(Pinned, pinned, PF_ANY) TESTSCFLAG(Pinned, pinned, PF_ANY) /* Xen */ PAGEFLAG(SavePinned, savepinned, PF_ANY); /* Xen */ PAGEFLAG(Foreign, foreign, PF_ANY); /* Xen */ @@ -280,12 +280,15 @@ PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY) * Only test-and-set exist for PG_writeback. The unconditional operators are * risky: they bypass page accounting. */ -TESTPAGEFLAG(Writeback, writeback, PF_ANY) TESTSCFLAG(Writeback, writeback, PF_ANY) -PAGEFLAG(MappedToDisk, mappedtodisk, PF_ANY) +TESTPAGEFLAG(Writeback, writeback, PF_NO_COMPOUND) + TESTSCFLAG(Writeback, writeback, PF_NO_COMPOUND) +PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_COMPOUND) /* PG_readahead is only used for reads; PG_reclaim is only for writes */ -PAGEFLAG(Reclaim, reclaim, PF_ANY) TESTCLEARFLAG(Reclaim, reclaim, PF_ANY) -PAGEFLAG(Readahead, reclaim, PF_ANY) TESTCLEARFLAG(Readahead, reclaim, PF_ANY) +PAGEFLAG(Reclaim, reclaim, PF_NO_COMPOUND) + TESTCLEARFLAG(Reclaim, reclaim, PF_NO_COMPOUND) +PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND) + TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND) #ifdef CONFIG_HIGHMEM /* @@ -401,7 +404,7 @@ static inline int PageUptodate(struct page *page) static inline void __SetPageUptodate(struct page *page) { smp_wmb(); - __set_bit(PG_uptodate, &(page)->flags); + __set_bit(PG_uptodate, &page->flags); } static inline void SetPageUptodate(struct page *page) @@ -412,7 +415,7 @@ static inline void SetPageUptodate(struct page *page) * uptodate are actually visible before PageUptodate becomes true. */ smp_wmb(); - set_bit(PG_uptodate, &(page)->flags); + set_bit(PG_uptodate, &page->flags); } CLEARPAGEFLAG(Uptodate, uptodate, PF_ANY) -- 2.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
