| Message ID | a8f707e1-528d-b372-72f4-610939acae0c@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: XSA-40{1,2,8} follow-up | expand |
On 26/07/2022 17:07, Jan Beulich wrote: > Checks dependent on only d and x can be pulled out, thus allowing to > skip the flush mask calculation. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Do I get a Suggested-by seeing as this was on the very long list of improvements ? Either way, Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
On 27.07.2022 20:31, Andrew Cooper wrote: > On 26/07/2022 17:07, Jan Beulich wrote: >> Checks dependent on only d and x can be pulled out, thus allowing to >> skip the flush mask calculation. >> >> Signed-off-by: Jan Beulich <jbeulich@suse.com> > > Do I get a Suggested-by seeing as this was on the very long list of > improvements ? I can add one, but you weren't the only one to notice. > Either way, Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Thanks. Jan
--- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -3020,7 +3020,10 @@ static int _get_page_type(struct page_in if ( d && shadow_mode_enabled(d) ) shadow_prepare_page_type_change(d, page); - if ( (x ^ type) & PGT_type_mask ) + if ( ((x ^ type) & PGT_type_mask) && + /* Shadow mode: track only writable pages. */ + (!shadow_mode_enabled(d) || + ((x & PGT_type_mask) == PGT_writable_page)) ) { /* * On type change we check to flush stale TLB entries. It is @@ -3035,10 +3038,7 @@ static int _get_page_type(struct page_in /* Don't flush if the timestamp is old enough */ tlbflush_filter(mask, page->tlbflush_timestamp); - if ( unlikely(!cpumask_empty(mask)) && - /* Shadow mode: track only writable pages. */ - (!shadow_mode_enabled(d) || - ((x & PGT_type_mask) == PGT_writable_page)) ) + if ( unlikely(!cpumask_empty(mask)) ) { perfc_incr(need_flush_tlb_flush); /*
Checks dependent on only d and x can be pulled out, thus allowing to skip the flush mask calculation. Signed-off-by: Jan Beulich <jbeulich@suse.com>