On 31.05.2022 05:12, Penny Zheng wrote: > Pages used as guest RAM for static domain, shall be reserved to this > domain only. > So in case reserved pages being used for other purpose, users > shall not free them back to heap, even when last ref gets dropped. > > free_staticmem_pages will be called by free_heap_pages in runtime > for static domain freeing memory resource, so let's drop the __init > flag. > > Signed-off-by: Penny Zheng <penny.zh...@arm.com> > --- > v5 changes: > - In order to avoid stub functions, we #define PGC_staticmem to non-zero only > when CONFIG_STATIC_MEMORY > - use "unlikely()" around pg->count_info & PGC_staticmem > - remove pointless "if", since mark_page_free() is going to set count_info > to PGC_state_free and by consequence clear PGC_staticmem > - move #define PGC_staticmem 0 to mm.h > --- > v4 changes: > - no changes > --- > v3 changes: > - fix possible racy issue in free_staticmem_pages() > - introduce a stub free_staticmem_pages() for the !CONFIG_STATIC_MEMORY case > - move the change to free_heap_pages() to cover other potential call sites > - fix the indentation > --- > v2 changes: > - new commit > --- > xen/arch/arm/include/asm/mm.h | 2 ++ > xen/common/page_alloc.c | 16 +++++++++------- > xen/include/xen/mm.h | 6 +++++- > 3 files changed, 16 insertions(+), 8 deletions(-) > > diff --git a/xen/arch/arm/include/asm/mm.h b/xen/arch/arm/include/asm/mm.h > index 1226700085..56d0939318 100644 > --- a/xen/arch/arm/include/asm/mm.h > +++ b/xen/arch/arm/include/asm/mm.h > @@ -108,9 +108,11 @@ struct page_info > /* Page is Xen heap? */ > #define _PGC_xen_heap PG_shift(2) > #define PGC_xen_heap PG_mask(1, 2) > +#ifdef CONFIG_STATIC_MEMORY > /* Page is static memory */ > #define _PGC_staticmem PG_shift(3) > #define PGC_staticmem PG_mask(1, 3) > +#endif > /* ... */ > /* Page is broken? */ > #define _PGC_broken PG_shift(7) > diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c > index 44600dd9cd..6425761116 100644 > --- a/xen/common/page_alloc.c > +++ b/xen/common/page_alloc.c > @@ -151,10 +151,6 @@ > #define p2m_pod_offline_or_broken_replace(pg) BUG_ON(pg != NULL) > #endif > > -#ifndef PGC_staticmem > -#define PGC_staticmem 0 > -#endif > -
Is the moving of this into the header really a necessary part of this change? Afaics the symbol is still only ever used in this one C file. > --- a/xen/include/xen/mm.h > +++ b/xen/include/xen/mm.h > @@ -85,10 +85,10 @@ bool scrub_free_pages(void); > } while ( false ) > #define FREE_XENHEAP_PAGE(p) FREE_XENHEAP_PAGES(p, 0) > > -#ifdef CONFIG_STATIC_MEMORY > /* These functions are for static memory */ > void free_staticmem_pages(struct page_info *pg, unsigned long nr_mfns, > bool need_scrub); > +#ifdef CONFIG_STATIC_MEMORY > int acquire_domstatic_pages(struct domain *d, mfn_t smfn, unsigned int > nr_mfns, > unsigned int memflags); > #endif Is the #ifdef really worth retaining at this point? Code is generally better readable without. Jan
