[Xen-devel,v3,8/8] xen: arm: allocate more than one bank for 1:1 domain 0 if needed

Message ID	1403777837-16779-8-git-send-email-ian.campbell@citrix.com
State	New
Headers	show Return-Path: <patchwork-forward+bncBC4Y5F6PT4PBBMXHV6OQKGQEE4XTDSY@linaro.org> Received-SPF: pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.220.180 as permitted sender) client-ip=209.85.220.180; Received-SPF: none (google.com: xen-devel-bounces@lists.xen.org does not designate permitted sender hosts) client-ip=50.57.142.19; From: Ian Campbell <ian.campbell@citrix.com> To: <xen-devel@lists.xen.org> Date: Thu, 26 Jun 2014 11:17:17 +0100 Message-ID: <1403777837-16779-8-git-send-email-ian.campbell@citrix.com> In-Reply-To: <1403777793.16595.21.camel@kazak.uk.xensource.com> References: <1403777793.16595.21.camel@kazak.uk.xensource.com> MIME-Version: 1.0 Cc: julien.grall@linaro.org, tim@xen.org, Ian Campbell <ian.campbell@citrix.com>, stefano.stabellini@eu.citrix.com Subject: [Xen-devel] [PATCH v3 8/8] xen: arm: allocate more than one bank for 1:1 domain 0 if needed Precedence: list Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 9d9cba9..3fdb20e 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -45,6 +45,13 @@ custom_param("dom0_mem", parse_dom0_mem); # define DPRINT(fmt, args...) do {} while ( 0 ) #endif +//#define DEBUG_11_ALLOCATION +#ifdef DEBUG_11_ALLOCATION +# define D11PRINT(fmt, args...) printk(XENLOG_DEBUG fmt, ##args) +#else +# define D11PRINT(fmt, args...) do {} while ( 0 ) +#endif + /* * Amount of extra space required to dom0's device tree. No new nodes * are added (yet) but one terminating reserve map entry (16 bytes) is @@ -67,39 +74,274 @@ struct vcpu *__init alloc_dom0_vcpu0(struct domain *dom0) return alloc_vcpu(dom0, 0, 0); } -static void allocate_memory_11(struct domain *d, struct kernel_info *kinfo) +static unsigned int get_11_allocation_size(paddr_t size) { - paddr_t start; - paddr_t size; - struct page_info *pg; - unsigned int order = get_order_from_bytes(dom0_mem); - int res; - paddr_t spfn; + /* + * get_order_from_bytes returns the order greater than or equal to + * the given size, but we need less than or equal. Adding one to + * the size pushes an evenly aligned size into the next order, so + * we can then unconditionally subtract 1 from the order which is + * returned. + */ + return get_order_from_bytes(size + 1) - 1; +} - if ( is_32bit_domain(d) ) - pg = alloc_domheap_pages(d, order, MEMF_bits(32)); - else - pg = alloc_domheap_pages(d, order, 0); - if ( !pg ) - panic("Failed to allocate contiguous memory for dom0"); +/* + * Insert the given pages into a memory bank, banks are ordered by address. + * + * Returns false if the memory would be below bank 0 or we have run + * out of banks. In this case it will free the pages. + */ +static bool_t insert_11_bank(struct domain *d, + struct kernel_info *kinfo, + struct page_info *pg, + unsigned int order) +{ + int res, i; + paddr_t spfn; + paddr_t start, size; spfn = page_to_mfn(pg); start = pfn_to_paddr(spfn); size = pfn_to_paddr((1 << order)); - // 1:1 mapping - printk("Populate P2M %#"PRIx64"->%#"PRIx64" (1:1 mapping for dom0)\n", - start, start + size); - res = guest_physmap_add_page(d, spfn, spfn, order); + D11PRINT("Allocated %#"PRIpaddr"-%#"PRIpaddr" (%ldMB/%ldMB, order %d)\n", + start, start + size, + 1UL << (order+PAGE_SHIFT-20), + /* Don't want format this as PRIpaddr (16 digit hex) */ + (unsigned long)(kinfo->unassigned_mem >> 20), + order); - if ( res ) - panic("Unable to add pages in DOM0: %d", res); + if ( kinfo->mem.nr_banks > 0 && start + size < kinfo->mem.bank[0].start ) + { + D11PRINT("Allocation is below bank 0, not using\n"); + goto fail; + } - kinfo->mem.bank[0].start = start; - kinfo->mem.bank[0].size = size; - kinfo->mem.nr_banks = 1; + res = guest_physmap_add_page(d, spfn, spfn, order); + if ( res ) + panic("Failed map pages to DOM0: %d", res); kinfo->unassigned_mem -= size; + + if ( kinfo->mem.nr_banks == 0 ) + { + kinfo->mem.bank[0].start = start; + kinfo->mem.bank[0].size = size; + kinfo->mem.nr_banks = 1; + return true; + } + + for( i = 0; i < kinfo->mem.nr_banks; i++ ) + { + struct membank *bank = &kinfo->mem.bank[i]; + + /* If possible merge new memory into the start of the bank */ + if ( bank->start == start+size ) + { + bank->start = start; + bank->size += size; + return true; + } + + /* If possible merge new memory onto the end of the bank */ + if ( start == bank->start + bank->size ) + { + bank->size += size; + return true; + } + + /* + * Otherwise if it is below this bank insert new memory in a + * new bank before this one. If there was a lower bank we + * could have inserted the memory into/before we would already + * have done so, so this must be the right place. + */ + if ( start + size < bank->start && kinfo->mem.nr_banks < NR_MEM_BANKS ) + { + memmove(bank + 1, bank, sizeof(*bank)*(kinfo->mem.nr_banks - i)); + kinfo->mem.nr_banks++; + bank->start = start; + bank->size = size; + return true; + } + } + + if ( i == kinfo->mem.nr_banks && kinfo->mem.nr_banks < NR_MEM_BANKS ) + { + struct membank *bank = &kinfo->mem.bank[kinfo->mem.nr_banks]; + + bank->start = start; + bank->size = size; + kinfo->mem.nr_banks++; + return true; + } + + /* If we get here then there are no more banks to fill. */ + +fail: + free_domheap_pages(pg, order); + return false; +} + +/* + * This is all pretty horrible. + * + * Requirements: + * + * 1. The dom0 kernel should be loaded within the first 128MB of RAM. This + * is necessary at least for Linux zImage kernels, which are all we + * support today. + * 2. We want to put the dom0 kernel, ramdisk and DTB in the same + * bank. Partly this is just easier for us to deal with, but also + * the ramdisk and DTB must be placed within a certain proximity of + * the kernel within RAM. + * 3. For 32-bit dom0 we want to place as much of the RAM as we + * reasonably can below 4GB, so that it can be used by non-LPAE + * enabled kernels. + * 4. For 32-bit dom0 the kernel must be located below 4GB. + * 5. We want to have a few largers banks rather than many smaller ones. + * + * For the first two requirements we need to make sure that the lowest + * bank is sufficiently large. + * + * For convenience we also sort the banks by physical address. + * + * The memory allocator does not really give us the flexibility to + * meet these requirements directly. So instead of proceed as follows: + * + * We first allocate the largest allocation we can as low as we + * can. This then becomes the first bank. This bank must be at least + * 128MB (or dom0_mem if that is smaller). + * + * Then we start allocating more memory, trying to allocate the + * largest possible size and trying smaller sizes until we + * successfully allocate something. + * + * We then try and insert this memory in to the list of banks. If it + * can be merged into an existing bank then this is trivial. + * + * If the new memory is before the first bank (and cannot be merged + * into it) then we give up. Since the allocator prefers to allocate + * high addresses first and the first bank has already been allocated + * to be as low as possible this likely means we wouldn't have been + * able to allocate much more memory anyway. + * + * Otherwise we insert a new bank. If we've reached MAX_NR_BANKS then + * we give up. + * + * For 32-bit domain we require that the initial allocation for the + * first bank is under 4G. Then for the subsequent allocations we + * initially allocate memory only from below 4GB. Once that runs out + * (as described above) we allow higher allocations and continue until + * that runs out (or we have allocated sufficient dom0 memory). + */ +static void allocate_memory_11(struct domain *d, struct kernel_info *kinfo) +{ + const unsigned int min_low_order = + get_order_from_bytes(min_t(paddr_t, dom0_mem, MB(128))); + const unsigned int min_order = get_order_from_bytes(MB(4)); + struct page_info *pg; + unsigned int order = get_11_allocation_size(kinfo->unassigned_mem); + int i; + + bool_t lowmem = is_32bit_domain(d); + unsigned int bits; + + printk("Allocating 1:1 mappings totalling %ldMB for dom0:\n", + /* Don't want format this as PRIpaddr (16 digit hex) */ + (unsigned long)(kinfo->unassigned_mem >> 20)); + + kinfo->mem.nr_banks = 0; + + /* + * First try and allocate the largest thing we can as low as + * possible to be bank 0. + */ + while ( order >= min_low_order ) + { + for ( bits = order ; bits < (lowmem ? 32 : PADDR_BITS); bits++ ) + { + pg = alloc_domheap_pages(d, order, MEMF_bits(bits)); + if ( pg != NULL ) + goto got_bank0; + } + order--; + } + + panic("Unable to allocate first memory bank"); + + got_bank0: + + if ( !insert_11_bank(d, kinfo, pg, order) ) + BUG(); /* Cannot fail for first bank */ + + /* Now allocate more memory and fill in additional banks */ + + order = get_11_allocation_size(kinfo->unassigned_mem); + while ( kinfo->unassigned_mem && kinfo->mem.nr_banks < NR_MEM_BANKS ) + { + pg = alloc_domheap_pages(d, order, lowmem ? MEMF_bits(32) : 0); + if ( !pg ) + { + order --; + + if ( lowmem && order < min_low_order) + { + D11PRINT("Failed at min_low_order, allow high allocations\n"); + order = get_11_allocation_size(kinfo->unassigned_mem); + lowmem = false; + continue; + } + if ( order >= min_order ) + continue; + + /* No more we can do */ + break; + } + + if ( !insert_11_bank(d, kinfo, pg, order) ) + { + if ( kinfo->mem.nr_banks == NR_MEM_BANKS ) + /* Nothing more we can do. */ + break; + + if ( lowmem ) + { + D11PRINT("Allocation below bank 0, allow high allocations\n"); + order = get_11_allocation_size(kinfo->unassigned_mem); + lowmem = false; + continue; + } + else + { + D11PRINT("Allocation below bank 0\n"); + break; + } + } + + /* + * Success, next time around try again to get the largest order + * allocation possible. + */ + order = get_11_allocation_size(kinfo->unassigned_mem); + } + + if ( kinfo->unassigned_mem ) + printk("WARNING: Failed to allocate requested dom0 memory." + /* Don't want format this as PRIpaddr (16 digit hex) */ + " %ldMB unallocated\n", + (unsigned long)kinfo->unassigned_mem >> 20); + + for( i = 0; i < kinfo->mem.nr_banks; i++ ) + { + printk("BANK[%d] %#"PRIpaddr"-%#"PRIpaddr" (%ldMB)\n", + i, + kinfo->mem.bank[i].start, + kinfo->mem.bank[i].start + kinfo->mem.bank[i].size, + /* Don't want format this as PRIpaddr (16 digit hex) */ + (unsigned long)(kinfo->mem.bank[i].size >> 20)); + } } static void allocate_memory(struct domain *d, struct kernel_info *kinfo)

[Xen-devel,v3,8/8] xen: arm: allocate more than one bank for 1:1 domain 0 if needed

Commit Message

Comments

Patch