On Tue, 29 May 2007, Mel Gorman wrote: > CONFIG_MIGRATION currently depends on CONFIG_NUMA. move_pages() is the only > user of migration today and as this system call is only meaningful on NUMA, > it makes sense. However, memory compaction will operate within a zone and is > useful on both NUMA and non-NUMA systems. This patch allows CONFIG_MIGRATION > to be used in all memory models. To preserve existing behaviour, move_pages() > is only available when CONFIG_NUMA is set.
Hmmm... I thought I had this already set up so that it would be easy to switch page migration to not depend on CONFIG_NUMA. Not so it seems. > --- linux-2.6.22-rc2-mm1-005_migrate_nocontext/include/linux/migrate.h > 2007-05-28 14:11:32.000000000 +0100 > +++ linux-2.6.22-rc2-mm1-015_migration_flatmem/include/linux/migrate.h > 2007-05-29 10:00:09.000000000 +0100 > @@ -7,7 +7,7 @@ > > typedef struct page *new_page_t(struct page *, unsigned long private, int > **); > > -#ifdef CONFIG_MIGRATION > +#ifdef CONFIG_SYSCALL_MOVE_PAGES > /* Check if a vma is migratable */ > static inline int vma_migratable(struct vm_area_struct *vma) > { > @@ -24,7 +24,14 @@ static inline int vma_migratable(struct > return 0; > return 1; > } > +#else > +static inline int vma_migratable(struct vm_area_struct *vma) > +{ > + return 0; > +} > +#endif I guess we get compilation failures because of the reference to policy_zone here for the !NUMA case? I think vma migratable is not used at all if !NUMA. > +#ifdef CONFIG_MIGRATION > extern int isolate_lru_page(struct page *p, struct list_head *pagelist); > extern int putback_lru_pages(struct list_head *l); > extern int migrate_page(struct address_space *, > @@ -40,8 +47,6 @@ extern int migrate_vmas(struct mm_struct > const nodemask_t *from, const nodemask_t *to, > unsigned long flags); > #else > -static inline int vma_migratable(struct vm_area_struct *vma) > - { return 0; } Maybe this block is not necessary? > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff > linux-2.6.22-rc2-mm1-005_migrate_nocontext/include/linux/mm.h > linux-2.6.22-rc2-mm1-015_migration_flatmem/include/linux/mm.h > --- linux-2.6.22-rc2-mm1-005_migrate_nocontext/include/linux/mm.h > 2007-05-24 10:13:34.000000000 +0100 > +++ linux-2.6.22-rc2-mm1-015_migration_flatmem/include/linux/mm.h > 2007-05-28 14:13:44.000000000 +0100 > @@ -242,6 +242,8 @@ struct vm_operations_struct { > int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); > struct mempolicy *(*get_policy)(struct vm_area_struct *vma, > unsigned long addr); > +#endif /* CONFIG_NUMA */ > +#ifdef CONFIG_MIGRATION > int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from, > const nodemask_t *to, unsigned long flags); > #endif Correct. > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff > linux-2.6.22-rc2-mm1-005_migrate_nocontext/mm/Kconfig > linux-2.6.22-rc2-mm1-015_migration_flatmem/mm/Kconfig > --- linux-2.6.22-rc2-mm1-005_migrate_nocontext/mm/Kconfig 2007-05-24 > 10:13:34.000000000 +0100 > +++ linux-2.6.22-rc2-mm1-015_migration_flatmem/mm/Kconfig 2007-05-29 > 09:57:23.000000000 +0100 > @@ -145,13 +145,16 @@ config SPLIT_PTLOCK_CPUS > config MIGRATION > bool "Page migration" > def_bool y > - depends on NUMA > help > Allows the migration of the physical location of pages of processes > while the virtual addresses are not changed. This is useful for > example on NUMA systems to put pages nearer to the processors > accessing > the page. > > +config SYSCALL_MOVE_PAGES > + def_bool y > + depends on MIGRATION && NUMA > + Do we really need the CONFIG_SYSCALL_MOVE_PAGES? I think you will directly access the lower levels. So why have it? CONFIG_SYSCALL_MOVE_PAGES == CONFIG_NUMA. - 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/