[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [PATCH v3 03/19] xen/arm: p2m: Replace level_{orders, masks} arrays with XEN_PT_LEVEL_{ORDER, MASK}
Hi Julien, > On 21 Feb 2022, at 10:22, Julien Grall <julien@xxxxxxx> wrote: > > From: Julien Grall <jgrall@xxxxxxxxxx> > > The array level_orders and level_masks can be replaced with the > recently introduced macros LEVEL_ORDER and LEVEL_MASK. > > Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx> Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx> One open question: At this stage the convenience aliases that you kept in include/asm/lpae.h are used in a very limited number of places. Could we remove those and use only XEN_PT_LEVEL_* to make the code a bit more coherent. Not something to do here but could be done in a following patch after this serie Cheers Bertrand > > --- > Changes in v3: > - Fix clashes after prefixing the PT macros with XEN_PT_ > > Changes in v2: > - New patch > > The goal is to remove completely the static arrays so they > don't need to be global (or duplicated) when adding superpage > support for Xen PT. > > This also has the added benefits to replace a couple of loads > with only a few instructions working on immediate. > --- > xen/arch/arm/p2m.c | 17 ++++++----------- > 1 file changed, 6 insertions(+), 11 deletions(-) > > diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c > index 493a1e25879a..1d1059f7d2bd 100644 > --- a/xen/arch/arm/p2m.c > +++ b/xen/arch/arm/p2m.c > @@ -37,12 +37,6 @@ static unsigned int __read_mostly max_vmid = > MAX_VMID_8_BIT; > */ > unsigned int __read_mostly p2m_ipa_bits = 64; > > -/* Helpers to lookup the properties of each level */ > -static const paddr_t level_masks[] = > - { ZEROETH_MASK, FIRST_MASK, SECOND_MASK, THIRD_MASK }; > -static const uint8_t level_orders[] = > - { ZEROETH_ORDER, FIRST_ORDER, SECOND_ORDER, THIRD_ORDER }; > - > static mfn_t __read_mostly empty_root_mfn; > > static uint64_t generate_vttbr(uint16_t vmid, mfn_t root_mfn) > @@ -233,7 +227,7 @@ static lpae_t *p2m_get_root_pointer(struct p2m_domain > *p2m, > * we can't use (P2M_ROOT_LEVEL - 1) because the root level might be > * 0. Yet we still want to check if all the unused bits are zeroed. > */ > - root_table = gfn_x(gfn) >> (level_orders[P2M_ROOT_LEVEL] + > + root_table = gfn_x(gfn) >> (XEN_PT_LEVEL_ORDER(P2M_ROOT_LEVEL) + > XEN_PT_LPAE_SHIFT); > if ( root_table >= P2M_ROOT_PAGES ) > return NULL; > @@ -380,7 +374,7 @@ mfn_t p2m_get_entry(struct p2m_domain *p2m, gfn_t gfn, > if ( gfn_x(gfn) > gfn_x(p2m->max_mapped_gfn) ) > { > for ( level = P2M_ROOT_LEVEL; level < 3; level++ ) > - if ( (gfn_x(gfn) & (level_masks[level] >> PAGE_SHIFT)) > > + if ( (gfn_x(gfn) & (XEN_PT_LEVEL_MASK(level) >> PAGE_SHIFT)) > > gfn_x(p2m->max_mapped_gfn) ) > break; > > @@ -423,7 +417,8 @@ mfn_t p2m_get_entry(struct p2m_domain *p2m, gfn_t gfn, > * The entry may point to a superpage. Find the MFN associated > * to the GFN. > */ > - mfn = mfn_add(mfn, gfn_x(gfn) & ((1UL << level_orders[level]) - 1)); > + mfn = mfn_add(mfn, > + gfn_x(gfn) & ((1UL << XEN_PT_LEVEL_ORDER(level)) - 1)); > > if ( valid ) > *valid = lpae_is_valid(entry); > @@ -434,7 +429,7 @@ out_unmap: > > out: > if ( page_order ) > - *page_order = level_orders[level]; > + *page_order = XEN_PT_LEVEL_ORDER(level); > > return mfn; > } > @@ -808,7 +803,7 @@ static bool p2m_split_superpage(struct p2m_domain *p2m, > lpae_t *entry, > /* Convenience aliases */ > mfn_t mfn = lpae_get_mfn(*entry); > unsigned int next_level = level + 1; > - unsigned int level_order = level_orders[next_level]; > + unsigned int level_order = XEN_PT_LEVEL_ORDER(next_level); > > /* > * This should only be called with target != level and the entry is > -- > 2.32.0 >
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |