From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Egger Subject: Re: [PATCH 1 of 4] p2m: Keep statistics on order of p2m entries Date: Fri, 6 May 2011 16:53:46 +0200 Message-ID: <4DC40B7A.4010605@amd.com> References: <4DC40841.9020108@amd.com> <20110506150028.GF24068@whitby.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110506150028.GF24068@whitby.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Tim Deegan Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 05/06/11 17:00, Tim Deegan wrote: > Hello, > > At 15:40 +0100 on 06 May (1304696401), Christoph Egger wrote: >> Can you please use defines for the indexes of p2m->stats.entries[], >> please? That makes it easier to read what you are counting. > > I'm not sure that's a great idea. The array is indexed in several > places by integer already, and the defines are unlikely to be much more > illuminating unless you can think of some better naming scheme than > "#define LEVEL_0 0" etc. What about this: #define PAGE_ORDER_4K 0 #define PAGE_ORDER_2M 9 #define PAGE_ORDER_1G 18 > > On the other hand, maybe the array itself could have a more descriptive > name than "stats.entries". > > Tim. > >> On 05/06/11 16:01, George Dunlap wrote: >>> Count the number of 4kiB, 2MiB, and 1GiB p2m entries. >>> >>> Signed-off-by: George Dunlap >>> >>> diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/hap/p2m-ept.c >>> --- a/xen/arch/x86/mm/hap/p2m-ept.c Thu May 05 17:40:34 2011 +0100 >>> +++ b/xen/arch/x86/mm/hap/p2m-ept.c Fri May 06 15:01:08 2011 +0100 >>> @@ -39,6 +39,8 @@ >>> >>> #define is_epte_present(ept_entry) ((ept_entry)->epte& 0x7) >>> #define is_epte_superpage(ept_entry) ((ept_entry)->sp) >>> +#define is_epte_countable(ept_entry) (is_epte_present(ept_entry) \ >>> + || ((ept_entry)->sa_p2mt == p2m_populate_on_demand)) >>> >>> /* Non-ept "lock-and-check" wrapper */ >>> static int ept_pod_check_and_populate(struct p2m_domain *p2m, unsigned long gfn, >>> @@ -167,11 +169,14 @@ >>> void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int level) >>> { >>> /* End if the entry is a leaf entry. */ >>> - if ( level == 0 || !is_epte_present(ept_entry) || >>> - is_epte_superpage(ept_entry) ) >>> + if ( level == 0 || !is_epte_present(ept_entry) || is_epte_superpage(ept_entry) ) >>> + { >>> + if ( is_epte_countable(ept_entry) ) >>> + p2m->stats.entries[level]--; >>> return; >>> + } >>> >>> - if ( level> 1 ) >>> + if ( level> 0 ) >>> { >>> ept_entry_t *epte = map_domain_page(ept_entry->mfn); >>> for ( int i = 0; i< EPT_PAGETABLE_ENTRIES; i++ ) >>> @@ -217,7 +222,10 @@ >>> ept_p2m_type_to_flags(epte, epte->sa_p2mt, epte->access); >>> >>> if ( (level - 1) == target ) >>> + { >>> + p2m->stats.entries[target]++; >>> continue; >>> + } >>> >>> ASSERT(is_epte_superpage(epte)); >>> >>> @@ -400,6 +408,10 @@ >>> ept_p2m_type_to_flags(&new_entry, p2mt, p2ma); >>> } >>> >>> + /* old_entry will be handled by ept_free_entry below */ >>> + if ( is_epte_countable(&new_entry) ) >>> + p2m->stats.entries[i]++; >>> + >>> atomic_write_ept_entry(ept_entry, new_entry); >>> } >>> else >>> @@ -412,12 +424,16 @@ >>> >>> split_ept_entry = atomic_read_ept_entry(ept_entry); >>> >>> + /* Accounting should be OK here; split_ept_entry bump the counts, >>> + * free_entry will reduce them. */ >>> if ( !ept_split_super_page(p2m,&split_ept_entry, i, target) ) >>> { >>> ept_free_entry(p2m,&split_ept_entry, i); >>> goto out; >>> } >>> >>> + /* We know this was countable or we wouldn't be here.*/ >>> + p2m->stats.entries[i]--; >>> /* now install the newly split ept sub-tree */ >>> /* NB: please make sure domian is paused and no in-fly VT-d DMA. */ >>> atomic_write_ept_entry(ept_entry, split_ept_entry); >>> @@ -449,9 +465,13 @@ >>> >>> ept_p2m_type_to_flags(&new_entry, p2mt, p2ma); >>> >>> + /* old_entry will be handled by ept_free_entry below */ >>> + if ( is_epte_countable(&new_entry) ) >>> + p2m->stats.entries[i]++; >>> + >>> atomic_write_ept_entry(ept_entry, new_entry); >>> } >>> - >>> + >>> /* Track the highest gfn for which we have ever had a valid mapping */ >>> if ( mfn_valid(mfn_x(mfn))&& >>> (gfn + (1UL<< order) - 1> p2m->max_mapped_pfn) ) >>> diff -r 4b0692880dfa -r be5d93d38f28 xen/arch/x86/mm/p2m.c >>> --- a/xen/arch/x86/mm/p2m.c Thu May 05 17:40:34 2011 +0100 >>> +++ b/xen/arch/x86/mm/p2m.c Fri May 06 15:01:08 2011 +0100 >>> @@ -184,11 +184,15 @@ >>> { >>> /* End if the entry is a leaf entry. */ >>> if ( page_order == 0 >>> - || !(l1e_get_flags(*p2m_entry)& _PAGE_PRESENT) >>> + || !(l1e_get_flags(*p2m_entry)& _PAGE_PRESENT) >>> || (l1e_get_flags(*p2m_entry)& _PAGE_PSE) ) >>> + { >>> + if ( l1e_get_flags(*p2m_entry) ) >>> + p2m->stats.entries[page_order/9]--; >>> return; >>> - >>> - if ( page_order> 9 ) >>> + } >>> + >>> + if ( page_order ) >>> { >>> l1_pgentry_t *l3_table = map_domain_page(l1e_get_pfn(*p2m_entry)); >>> for ( int i = 0; i< L3_PAGETABLE_ENTRIES; i++ ) >>> @@ -242,6 +246,7 @@ >>> new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)), >>> __PAGE_HYPERVISOR | _PAGE_USER); >>> >>> + /* Stats: Empty entry, no mods needed */ >>> switch ( type ) { >>> case PGT_l3_page_table: >>> p2m_add_iommu_flags(&new_entry, 3, IOMMUF_readable|IOMMUF_writable); >>> @@ -285,10 +290,12 @@ >>> { >>> new_entry = l1e_from_pfn(pfn + (i * L1_PAGETABLE_ENTRIES), flags); >>> p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable); >>> + p2m->stats.entries[1]++; >>> p2m->write_p2m_entry(p2m, gfn, >>> l1_entry+i, *table_mfn, new_entry, 2); >>> } >>> unmap_domain_page(l1_entry); >>> + p2m->stats.entries[2]--; >>> new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)), >>> __PAGE_HYPERVISOR|_PAGE_USER); //disable PSE >>> p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable); >>> @@ -320,6 +327,7 @@ >>> { >>> new_entry = l1e_from_pfn(pfn + i, flags); >>> p2m_add_iommu_flags(&new_entry, 0, 0); >>> + p2m->stats.entries[0]++; >>> p2m->write_p2m_entry(p2m, gfn, >>> l1_entry+i, *table_mfn, new_entry, 1); >>> } >>> @@ -328,6 +336,7 @@ >>> new_entry = l1e_from_pfn(mfn_x(page_to_mfn(pg)), >>> __PAGE_HYPERVISOR|_PAGE_USER); >>> p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable); >>> + p2m->stats.entries[1]--; >>> p2m->write_p2m_entry(p2m, gfn, >>> p2m_entry, *table_mfn, new_entry, 2); >>> } >>> @@ -908,6 +917,15 @@ >>> void >>> p2m_pod_dump_data(struct p2m_domain *p2m) >>> { >>> + int i; >>> + long entries; >>> + printk(" P2M entry stats:\n"); >>> + for ( i=0; i<3; i++) >>> + if ( (entries=p2m->stats.entries[i]) ) >>> + printk(" L%d: %8ld entries, %ld bytes\n", >>> + i+1, >>> + entries, >>> + entries<<(i*9+12)); >>> printk(" PoD entries=%d cachesize=%d\n", >>> p2m->pod.entry_count, p2m->pod.count); >>> } >>> @@ -1475,6 +1493,12 @@ >>> old_mfn = l1e_get_pfn(*p2m_entry); >>> } >>> >>> + /* Adjust count for present/not-present entries added */ >>> + if ( l1e_get_flags(*p2m_entry) ) >>> + p2m->stats.entries[page_order/9]--; >>> + if ( l1e_get_flags(entry_content) ) >>> + p2m->stats.entries[page_order/9]++; >>> + >>> p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 3); >>> /* NB: paging_write_p2m_entry() handles tlb flushes properly */ >>> >>> @@ -1519,6 +1543,13 @@ >>> p2m_add_iommu_flags(&entry_content, 0, iommu_pte_flags); >>> old_mfn = l1e_get_pfn(*p2m_entry); >>> } >>> + >>> + /* Adjust count for present/not-present entries added */ >>> + if ( l1e_get_flags(*p2m_entry) ) >>> + p2m->stats.entries[page_order/9]--; >>> + if ( l1e_get_flags(entry_content) ) >>> + p2m->stats.entries[page_order/9]++; >>> + >>> /* level 1 entry */ >>> p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 1); >>> /* NB: paging_write_p2m_entry() handles tlb flushes properly */ >>> @@ -1556,6 +1587,12 @@ >>> old_mfn = l1e_get_pfn(*p2m_entry); >>> } >>> >>> + /* Adjust count for present/not-present entries added */ >>> + if ( l1e_get_flags(*p2m_entry) ) >>> + p2m->stats.entries[page_order/9]--; >>> + if ( l1e_get_flags(entry_content) ) >>> + p2m->stats.entries[page_order/9]++; >>> + >>> p2m->write_p2m_entry(p2m, gfn, p2m_entry, table_mfn, entry_content, 2); >>> /* NB: paging_write_p2m_entry() handles tlb flushes properly */ >>> >>> @@ -2750,6 +2787,8 @@ >>> continue; >>> } >>> >>> + /* STATS: Should change only type; no stats should need adjustment */ >>> + >>> l2mfn = _mfn(l3e_get_pfn(l3e[i3])); >>> l2e = map_domain_page(l3e_get_pfn(l3e[i3])); >>> for ( i2 = 0; i2< L2_PAGETABLE_ENTRIES; i2++ ) >>> diff -r 4b0692880dfa -r be5d93d38f28 xen/include/asm-x86/p2m.h >>> --- a/xen/include/asm-x86/p2m.h Thu May 05 17:40:34 2011 +0100 >>> +++ b/xen/include/asm-x86/p2m.h Fri May 06 15:01:08 2011 +0100 >>> @@ -278,6 +278,10 @@ >>> unsigned reclaim_single; /* Last gpfn of a scan */ >>> unsigned max_guest; /* gpfn of max guest demand-populate */ >>> } pod; >>> + >>> + struct { >>> + long entries[3]; >>> + } stats; >>> }; >>> >>> /* get host p2m table */ -- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Einsteinring 24, 85689 Dornach b. 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