[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] [xen-unstable] x86: re-arrange struct page_info members
# HG changeset patch # User Keir Fraser <keir.fraser@xxxxxxxxxx> # Date 1233313843 0 # Node ID 162cdb596b9a7e49994b9305f34fadf92cfb3933 # Parent 6fe44eb28f525fc5879c43882ca089b9c636b3f6 x86: re-arrange struct page_info members By combining the overlay fields that are 8 bytes long (on x86-64) into a union separate from the one used for the 4 byte wide fields, no unnecessary padding will be inserted while at the same time avoiding to use __attribute__((__packed__)) on any of the sub-structures (which risks misaligning structure members without immediately noticing). Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx> --- xen/arch/x86/mm/shadow/common.c | 28 +++++++++++++-------------- xen/arch/x86/mm/shadow/multi.c | 28 +++++++++++++-------------- xen/arch/x86/mm/shadow/private.h | 2 - xen/include/asm-x86/mm.h | 40 +++++++++++++++++++++++++-------------- 4 files changed, 55 insertions(+), 43 deletions(-) diff -r 6fe44eb28f52 -r 162cdb596b9a xen/arch/x86/mm/shadow/common.c --- a/xen/arch/x86/mm/shadow/common.c Fri Jan 30 11:09:44 2009 +0000 +++ b/xen/arch/x86/mm/shadow/common.c Fri Jan 30 11:10:43 2009 +0000 @@ -1334,7 +1334,7 @@ static inline void trace_shadow_prealloc /* Convert smfn to gfn */ unsigned long gfn; ASSERT(mfn_valid(smfn)); - gfn = mfn_to_gfn(d, _mfn(mfn_to_shadow_page(smfn)->u.sh.back)); + gfn = mfn_to_gfn(d, _mfn(mfn_to_shadow_page(smfn)->v.sh.back)); __trace_var(TRC_SHADOW_PREALLOC_UNPIN, 0/*!tsc*/, sizeof(gfn), (unsigned char*)&gfn); } @@ -1542,7 +1542,7 @@ mfn_t shadow_alloc(struct domain *d, while ( i != order ) { i--; - sp->u.sh.order = i; + sp->v.free.order = i; page_list_add_tail(sp, &d->arch.paging.shadow.freelists[i]); sp += 1 << i; } @@ -1569,7 +1569,7 @@ mfn_t shadow_alloc(struct domain *d, sp[i].u.sh.type = shadow_type; sp[i].u.sh.pinned = 0; sp[i].u.sh.count = 0; - sp[i].u.sh.back = backpointer; + sp[i].v.sh.back = backpointer; set_next_shadow(&sp[i], NULL); perfc_incr(shadow_alloc_count); } @@ -1629,20 +1629,20 @@ void shadow_free(struct domain *d, mfn_t if ( (mfn_x(shadow_page_to_mfn(sp)) & mask) ) { /* Merge with predecessor block? */ if ( ((sp-mask)->u.sh.type != PGT_none) || - ((sp-mask)->u.sh.order != order) ) + ((sp-mask)->v.free.order != order) ) break; sp -= mask; page_list_del(sp, &d->arch.paging.shadow.freelists[order]); } else { /* Merge with successor block? */ if ( ((sp+mask)->u.sh.type != PGT_none) || - ((sp+mask)->u.sh.order != order) ) + ((sp+mask)->v.free.order != order) ) break; page_list_del(sp + mask, &d->arch.paging.shadow.freelists[order]); } } - sp->u.sh.order = order; + sp->v.free.order = order; page_list_add_tail(sp, &d->arch.paging.shadow.freelists[order]); } @@ -1825,7 +1825,7 @@ static unsigned int sh_set_allocation(st sp[j].u.sh.count = 0; sp[j].tlbflush_timestamp = 0; /* Not in any TLB */ } - sp->u.sh.order = order; + sp->v.free.order = order; page_list_add_tail(sp, &d->arch.paging.shadow.freelists[order]); } else if ( d->arch.paging.shadow.total_pages > pages ) @@ -1904,17 +1904,17 @@ static void sh_hash_audit_bucket(struct BUG_ON( sp->u.sh.type == 0 ); BUG_ON( sp->u.sh.type > SH_type_max_shadow ); /* Wrong bucket? */ - BUG_ON( sh_hash(sp->u.sh.back, sp->u.sh.type) != bucket ); + BUG_ON( sh_hash(sp->v.sh.back, sp->u.sh.type) != bucket ); /* Duplicate entry? */ for ( x = next_shadow(sp); x; x = next_shadow(x) ) - BUG_ON( x->u.sh.back == sp->u.sh.back && + BUG_ON( x->v.sh.back == sp->v.sh.back && x->u.sh.type == sp->u.sh.type ); /* Follow the backpointer to the guest pagetable */ if ( sp->u.sh.type != SH_type_fl1_32_shadow && sp->u.sh.type != SH_type_fl1_pae_shadow && sp->u.sh.type != SH_type_fl1_64_shadow ) { - struct page_info *gpg = mfn_to_page(_mfn(sp->u.sh.back)); + struct page_info *gpg = mfn_to_page(_mfn(sp->v.sh.back)); /* Bad shadow flags on guest page? */ BUG_ON( !(gpg->shadow_flags & (1<<sp->u.sh.type)) ); /* Bad type count on guest page? */ @@ -1930,7 +1930,7 @@ static void sh_hash_audit_bucket(struct { SHADOW_ERROR("MFN %#"PRpgmfn" shadowed (by %#"PRI_mfn")" " and not OOS but has typecount %#lx\n", - sp->u.sh.back, + sp->v.sh.back, mfn_x(shadow_page_to_mfn(sp)), gpg->u.inuse.type_info); BUG(); @@ -1944,7 +1944,7 @@ static void sh_hash_audit_bucket(struct { SHADOW_ERROR("MFN %#"PRpgmfn" shadowed (by %#"PRI_mfn")" " but has typecount %#lx\n", - sp->u.sh.back, mfn_x(shadow_page_to_mfn(sp)), + sp->v.sh.back, mfn_x(shadow_page_to_mfn(sp)), gpg->u.inuse.type_info); BUG(); } @@ -2030,7 +2030,7 @@ mfn_t shadow_hash_lookup(struct vcpu *v, prev = NULL; while(sp) { - if ( sp->u.sh.back == n && sp->u.sh.type == t ) + if ( sp->v.sh.back == n && sp->u.sh.type == t ) { /* Pull-to-front if 'sp' isn't already the head item */ if ( unlikely(sp != d->arch.paging.shadow.hash_table[key]) ) @@ -2197,7 +2197,7 @@ void sh_destroy_shadow(struct vcpu *v, m t == SH_type_fl1_64_shadow || t == SH_type_monitor_table || (is_pv_32on64_vcpu(v) && t == SH_type_l4_64_shadow) || - (page_get_owner(mfn_to_page(_mfn(sp->u.sh.back))) + (page_get_owner(mfn_to_page(_mfn(sp->v.sh.back))) == v->domain)); /* The down-shifts here are so that the switch statement is on nice diff -r 6fe44eb28f52 -r 162cdb596b9a xen/arch/x86/mm/shadow/multi.c --- a/xen/arch/x86/mm/shadow/multi.c Fri Jan 30 11:09:44 2009 +0000 +++ b/xen/arch/x86/mm/shadow/multi.c Fri Jan 30 11:10:43 2009 +0000 @@ -974,7 +974,7 @@ static int shadow_set_l2e(struct vcpu *v #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) { struct shadow_page_info *sp = mfn_to_shadow_page(sl1mfn); - mfn_t gl1mfn = _mfn(sp->u.sh.back); + mfn_t gl1mfn = _mfn(sp->v.sh.back); /* If the shadow is a fl1 then the backpointer contains the GFN instead of the GMFN, and it's definitely not @@ -1926,7 +1926,7 @@ void sh_destroy_l4_shadow(struct vcpu *v ASSERT(t == SH_type_l4_shadow); /* Record that the guest page isn't shadowed any more (in this type) */ - gmfn = _mfn(mfn_to_shadow_page(smfn)->u.sh.back); + gmfn = _mfn(mfn_to_shadow_page(smfn)->v.sh.back); delete_shadow_status(v, gmfn, t, smfn); shadow_demote(v, gmfn, t); /* Decrement refcounts of all the old entries */ @@ -1955,7 +1955,7 @@ void sh_destroy_l3_shadow(struct vcpu *v ASSERT(t == SH_type_l3_shadow); /* Record that the guest page isn't shadowed any more (in this type) */ - gmfn = _mfn(mfn_to_shadow_page(smfn)->u.sh.back); + gmfn = _mfn(mfn_to_shadow_page(smfn)->v.sh.back); delete_shadow_status(v, gmfn, t, smfn); shadow_demote(v, gmfn, t); @@ -1990,7 +1990,7 @@ void sh_destroy_l2_shadow(struct vcpu *v #endif /* Record that the guest page isn't shadowed any more (in this type) */ - gmfn = _mfn(mfn_to_shadow_page(smfn)->u.sh.back); + gmfn = _mfn(mfn_to_shadow_page(smfn)->v.sh.back); delete_shadow_status(v, gmfn, t, smfn); shadow_demote(v, gmfn, t); @@ -2020,12 +2020,12 @@ void sh_destroy_l1_shadow(struct vcpu *v /* Record that the guest page isn't shadowed any more (in this type) */ if ( t == SH_type_fl1_shadow ) { - gfn_t gfn = _gfn(mfn_to_shadow_page(smfn)->u.sh.back); + gfn_t gfn = _gfn(mfn_to_shadow_page(smfn)->v.sh.back); delete_fl1_shadow_status(v, gfn, smfn); } else { - mfn_t gmfn = _mfn(mfn_to_shadow_page(smfn)->u.sh.back); + mfn_t gmfn = _mfn(mfn_to_shadow_page(smfn)->v.sh.back); delete_shadow_status(v, gmfn, t, smfn); shadow_demote(v, gmfn, t); } @@ -2349,7 +2349,7 @@ static int validate_gl1e(struct vcpu *v, result |= shadow_set_l1e(v, sl1p, new_sl1e, sl1mfn); #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) - gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->u.sh.back); + gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->v.sh.back); if ( mfn_valid(gl1mfn) && mfn_is_out_of_sync(gl1mfn) ) { @@ -2968,7 +2968,7 @@ static int sh_page_fault(struct vcpu *v, sizeof(sl2e)) != 0) || !(shadow_l2e_get_flags(sl2e) & _PAGE_PRESENT) || !mfn_valid(gl1mfn = _mfn(mfn_to_shadow_page( - shadow_l2e_get_mfn(sl2e))->u.sh.back)) + shadow_l2e_get_mfn(sl2e))->v.sh.back)) || unlikely(mfn_is_out_of_sync(gl1mfn)) ) { /* Hit the slow path as if there had been no @@ -3530,7 +3530,7 @@ sh_invlpg(struct vcpu *v, unsigned long #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) /* Check to see if the SL1 is out of sync. */ { - mfn_t gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->u.sh.back); + mfn_t gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->v.sh.back); struct page_info *pg = mfn_to_page(gl1mfn); if ( mfn_valid(gl1mfn) && page_is_out_of_sync(pg) ) @@ -3560,7 +3560,7 @@ sh_invlpg(struct vcpu *v, unsigned long } sl1mfn = shadow_l2e_get_mfn(sl2e); - gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->u.sh.back); + gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->v.sh.back); pg = mfn_to_page(gl1mfn); if ( likely(sh_mfn_is_a_page_table(gl1mfn) @@ -4887,7 +4887,7 @@ int sh_audit_l1_table(struct vcpu *v, mf int done = 0; /* Follow the backpointer */ - gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->u.sh.back); + gl1mfn = _mfn(mfn_to_shadow_page(sl1mfn)->v.sh.back); #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) /* Out-of-sync l1 shadows can contain anything: just check the OOS hash */ @@ -4977,7 +4977,7 @@ int sh_audit_l2_table(struct vcpu *v, mf int done = 0; /* Follow the backpointer */ - gl2mfn = _mfn(mfn_to_shadow_page(sl2mfn)->u.sh.back); + gl2mfn = _mfn(mfn_to_shadow_page(sl2mfn)->v.sh.back); #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) /* Only L1's may be out of sync. */ @@ -5026,7 +5026,7 @@ int sh_audit_l3_table(struct vcpu *v, mf int done = 0; /* Follow the backpointer */ - gl3mfn = _mfn(mfn_to_shadow_page(sl3mfn)->u.sh.back); + gl3mfn = _mfn(mfn_to_shadow_page(sl3mfn)->v.sh.back); #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) /* Only L1's may be out of sync. */ @@ -5073,7 +5073,7 @@ int sh_audit_l4_table(struct vcpu *v, mf int done = 0; /* Follow the backpointer */ - gl4mfn = _mfn(mfn_to_shadow_page(sl4mfn)->u.sh.back); + gl4mfn = _mfn(mfn_to_shadow_page(sl4mfn)->v.sh.back); #if (SHADOW_OPTIMIZATIONS & SHOPT_OUT_OF_SYNC) /* Only L1's may be out of sync. */ diff -r 6fe44eb28f52 -r 162cdb596b9a xen/arch/x86/mm/shadow/private.h --- a/xen/arch/x86/mm/shadow/private.h Fri Jan 30 11:09:44 2009 +0000 +++ b/xen/arch/x86/mm/shadow/private.h Fri Jan 30 11:10:43 2009 +0000 @@ -631,7 +631,7 @@ static inline int sh_get_ref(struct vcpu if ( unlikely(nx >= 1U<<26) ) { SHADOW_PRINTK("shadow ref overflow, gmfn=%" PRpgmfn " smfn=%lx\n", - sp->u.sh.back, mfn_x(smfn)); + sp->v.sh.back, mfn_x(smfn)); return 0; } diff -r 6fe44eb28f52 -r 162cdb596b9a xen/include/asm-x86/mm.h --- a/xen/include/asm-x86/mm.h Fri Jan 30 11:09:44 2009 +0000 +++ b/xen/include/asm-x86/mm.h Fri Jan 30 11:10:43 2009 +0000 @@ -15,7 +15,7 @@ * 1. 'struct page_info' contains a 'struct page_list_entry list'. * 2. Provide a PFN_ORDER() macro for accessing the order of a free page. */ -#define PFN_ORDER(_pfn) ((_pfn)->u.free.order) +#define PFN_ORDER(_pfn) ((_pfn)->v.free.order) /* * This definition is solely for the use in struct page_info (and @@ -59,8 +59,6 @@ struct page_info /* Page is in use: ((count_info & PGC_count_mask) != 0). */ struct { - /* Owner of this page (NULL if page is anonymous). */ - u32 _domain; /* pickled format */ /* Type reference count and various PGT_xxx flags and fields. */ unsigned long type_info; } inuse; @@ -70,23 +68,37 @@ struct page_info unsigned long type:5; /* What kind of shadow is this? */ unsigned long pinned:1; /* Is the shadow pinned? */ unsigned long count:26; /* Reference count */ - union { - /* When in use, GMFN of guest page we're a shadow of. */ - __mfn_t back; - /* When free, order of the freelist we're on. */ - unsigned int order; - }; } sh; /* Page is on a free list: ((count_info & PGC_count_mask) == 0). */ struct { - /* Order-size of the free chunk this page is the head of. */ - u32 order; /* Mask of possibly-tainted TLBs. */ cpumask_t cpumask; } free; } u; + + union { + + /* Page is in use, but not as a shadow. */ + struct { + /* Owner of this page (NULL if page is anonymous). */ + u32 _domain; /* pickled format */ + } inuse; + + /* Page is in use as a shadow. */ + struct { + /* GMFN of guest page we're a shadow of. */ + __mfn_t back; + } sh; + + /* Page is on a free list (including shadow code free lists). */ + struct { + /* Order-size of the free chunk this page is the head of. */ + unsigned int order; + } free; + + } v; union { /* @@ -225,10 +237,10 @@ struct page_info #define SHADOW_OOS_FIXUPS 2 #define page_get_owner(_p) \ - ((struct domain *)((_p)->u.inuse._domain ? \ - mfn_to_virt((_p)->u.inuse._domain) : NULL)) + ((struct domain *)((_p)->v.inuse._domain ? \ + mfn_to_virt((_p)->v.inuse._domain) : NULL)) #define page_set_owner(_p,_d) \ - ((_p)->u.inuse._domain = (_d) ? virt_to_mfn(_d) : 0) + ((_p)->v.inuse._domain = (_d) ? virt_to_mfn(_d) : 0) #define maddr_get_owner(ma) (page_get_owner(maddr_to_page((ma)))) #define vaddr_get_owner(va) (page_get_owner(virt_to_page((va)))) _______________________________________________ Xen-changelog mailing list Xen-changelog@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-changelog
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |