On Wed, May 14, 2008 at 01:28:53PM -0700, Linus Torvalds wrote: > On Tue, 13 May 2008, Russ Anderson wrote: > > > > Minor source code cleanup of page flags in mm/page_alloc.c. > > Could we (a) make the naming reflect the *use* rather than the flags > involved and (b) perhaps add a comment about that use at the point of > definition? Yes, will do. The reason for the cleanup is the following patch defines PG_memerror, but only on configs with extended page flags. So checking them in page_alloc.c would require adding #ifdef, which would be rather ugly. Moving the definitions into page-flags.h allows the #ifdef to be in the header file rather than the C code. >From page.discard.v4: +#ifdef CONFIG_PAGEFLAGS_EXTENDED +PAGEFLAG(MemError, memerror) +#define PAGE_FLAGS (PAGE_FLAGS_BASE | 1UL << PG_memerror) +#else +PAGEFLAG_FALSE(MemError) +#define PAGE_FLAGS (PAGE_FLAGS_BASE) +#endif > > @@ -237,16 +237,7 @@ static void bad_page(struct page *page) > > printk(KERN_EMERG "Trying to fix it up, but a reboot is needed\n" > > KERN_EMERG "Backtrace:\n"); > > dump_stack(); > > - page->flags &= ~(1 << PG_lru | > > - 1 << PG_private | > > - 1 << PG_locked | > > - 1 << PG_active | > > - 1 << PG_dirty | > > - 1 << PG_reclaim | > > - 1 << PG_slab | > > - 1 << PG_swapcache | > > - 1 << PG_writeback | > > - 1 << PG_buddy ); > > + page->flags &= ~(PAGE_FLAGS_RECLAIM); > > Because here I'm now otherwise looking at the code, and I wonder > - why the extra odd parenthesis? > - what does PAGE_FLAG_RECLAIM mean? > > and it would be much nicer (I think) if the mask was instead called > something that reflected what it was all about, ie something along the > lines of PAGE_FLAG_CLEAR_WHEN_BAD instead. I'll make those changes. -- Russ Anderson, OS RAS/Partitioning Project Lead SGI - Silicon Graphics Inc rja@xxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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