This commit allows the user to set the cache coloring configuration for Dom0 via a command line parameter. Since cache coloring and static memory are incompatible, direct mapping Dom0 isn't possible when coloring is enabled.
A common configuration syntax for cache colors is also introduced. Based on original work from: Luca Miccio <lucmic...@gmail.com> Signed-off-by: Carlo Nonato <carlo.non...@minervasys.tech> Signed-off-by: Marco Solieri <marco.soli...@minervasys.tech> --- v5: - Carlo Nonato as the new author - moved dom0 colors parsing (parse_colors()) in this patch - added dom0_set_llc_colors() to set dom0 colors after creation - moved color allocation and checking in this patch - error handling when allocating color arrays - FIXME: copy pasted allocate_memory() cause it got moved v4: - dom0 colors are dynamically allocated as for any other domain (colors are duplicated in dom0_colors and in the new array, but logic is simpler) --- docs/misc/arm/cache-coloring.rst | 29 ++++++ docs/misc/xen-command-line.pandoc | 9 ++ xen/arch/arm/domain_build.c | 60 ++++++++++- xen/arch/arm/include/asm/llc-coloring.h | 1 + xen/arch/arm/llc-coloring.c | 128 ++++++++++++++++++++++++ 5 files changed, 224 insertions(+), 3 deletions(-) diff --git a/docs/misc/arm/cache-coloring.rst b/docs/misc/arm/cache-coloring.rst index eabf8f5d1b..acf82c3df8 100644 --- a/docs/misc/arm/cache-coloring.rst +++ b/docs/misc/arm/cache-coloring.rst @@ -84,6 +84,35 @@ More specific documentation is available at `docs/misc/xen-command-line.pandoc`. +----------------------+-------------------------------+ | ``llc-way-size`` | set the LLC way size | +----------------------+-------------------------------+ +| ``dom0-llc-colors`` | Dom0 color configuration | ++----------------------+-------------------------------+ + +Colors selection format +*********************** + +Regardless of the memory pool that has to be colored (Xen, Dom0/DomUs), +the color selection can be expressed using the same syntax. In particular a +comma-separated list of colors or ranges of colors is used. +Ranges are hyphen-separated intervals (such as `0-4`) and are inclusive on both +sides. + +Note that: + +- no spaces are allowed between values. +- no overlapping ranges or duplicated colors are allowed. +- values must be written in ascending order. + +Examples: + ++-------------------+-----------------------------+ +| **Configuration** | **Actual selection** | ++-------------------+-----------------------------+ +| 1-2,5-8 | [1, 2, 5, 6, 7, 8] | ++-------------------+-----------------------------+ +| 4-8,10,11,12 | [4, 5, 6, 7, 8, 10, 11, 12] | ++-------------------+-----------------------------+ +| 0 | [0] | ++-------------------+-----------------------------+ Known issues and limitations **************************** diff --git a/docs/misc/xen-command-line.pandoc b/docs/misc/xen-command-line.pandoc index 22d2d5b6cf..51f6adf035 100644 --- a/docs/misc/xen-command-line.pandoc +++ b/docs/misc/xen-command-line.pandoc @@ -963,6 +963,15 @@ Controls for the dom0 IOMMU setup. Specify a list of IO ports to be excluded from dom0 access. +### dom0-llc-colors (arm64) +> `= List of [ <integer> | <integer>-<integer> ]` + +> Default: `All available LLC colors` + +Specify dom0 LLC color configuration. This options is available only when +`CONFIG_LLC_COLORING` is enabled. If the parameter is not set, all available +colors are chosen and the user is warned on Xen serial console. + ### dom0_max_vcpus Either: diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 6945b9755d..482c059bfa 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2,6 +2,7 @@ #include <xen/init.h> #include <xen/compile.h> #include <xen/lib.h> +#include <xen/llc-coloring.h> #include <xen/mm.h> #include <xen/param.h> #include <xen/domain_page.h> @@ -414,7 +415,7 @@ static void __init allocate_memory_11(struct domain *d, } } -#ifdef CONFIG_DOM0LESS_BOOT +#if defined(CONFIG_DOM0LESS_BOOT) || defined(CONFIG_LLC_COLORING) bool __init allocate_bank_memory(struct domain *d, struct kernel_info *kinfo, gfn_t sgfn, paddr_t tot_size) { @@ -478,6 +479,49 @@ bool __init allocate_bank_memory(struct domain *d, struct kernel_info *kinfo, } #endif +static void __init allocate_memory(struct domain *d, struct kernel_info *kinfo) +{ + unsigned int i; + paddr_t bank_size; + + printk(XENLOG_INFO "Allocating mappings totalling %ldMB for %pd:\n", + /* Don't want format this as PRIpaddr (16 digit hex) */ + (unsigned long)(kinfo->unassigned_mem >> 20), d); + + kinfo->mem.nr_banks = 0; + bank_size = MIN(GUEST_RAM0_SIZE, kinfo->unassigned_mem); + if ( !allocate_bank_memory(d, kinfo, gaddr_to_gfn(GUEST_RAM0_BASE), + bank_size) ) + goto fail; + + bank_size = MIN(GUEST_RAM1_SIZE, kinfo->unassigned_mem); + if ( !allocate_bank_memory(d, kinfo, gaddr_to_gfn(GUEST_RAM1_BASE), + bank_size) ) + goto fail; + + if ( kinfo->unassigned_mem ) + goto fail; + + for( i = 0; i < kinfo->mem.nr_banks; i++ ) + { + printk(XENLOG_INFO "%pd BANK[%d] %#"PRIpaddr"-%#"PRIpaddr" (%ldMB)\n", + d, + 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)); + } + + return; + +fail: + panic("Failed to allocate requested domain memory." + /* Don't want format this as PRIpaddr (16 digit hex) */ + " %ldKB unallocated. Fix the VMs configurations.\n", + (unsigned long)kinfo->unassigned_mem >> 10); +} + /* * When PCI passthrough is available we want to keep the * "linux,pci-domain" in sync for every host bridge. @@ -2072,7 +2116,10 @@ static int __init construct_dom0(struct domain *d) /* type must be set before allocate_memory */ d->arch.type = kinfo.type; #endif - allocate_memory_11(d, &kinfo); + if ( is_domain_llc_colored(d) ) + allocate_memory(d, &kinfo); + else + allocate_memory_11(d, &kinfo); find_gnttab_region(d, &kinfo); rc = process_shm_chosen(d, &kinfo); @@ -2116,6 +2163,7 @@ void __init create_dom0(void) .max_maptrack_frames = -1, .grant_opts = XEN_DOMCTL_GRANT_version(opt_gnttab_max_version), }; + unsigned int flags = CDF_privileged; int rc; /* The vGIC for DOM0 is exactly emulating the hardware GIC */ @@ -2143,10 +2191,16 @@ void __init create_dom0(void) panic("SVE vector length error\n"); } - dom0 = domain_create(0, &dom0_cfg, CDF_privileged | CDF_directmap); + if ( !llc_coloring_enabled ) + flags |= CDF_directmap; + + dom0 = domain_create(0, &dom0_cfg, flags); if ( IS_ERR(dom0) ) panic("Error creating domain 0 (rc = %ld)\n", PTR_ERR(dom0)); + if ( llc_coloring_enabled && (rc = dom0_set_llc_colors(dom0)) ) + panic("Error initializing LLC coloring for domain 0 (rc = %d)", rc); + if ( alloc_dom0_vcpu0(dom0) == NULL ) panic("Error creating domain 0 vcpu0\n"); diff --git a/xen/arch/arm/include/asm/llc-coloring.h b/xen/arch/arm/include/asm/llc-coloring.h index 7885e9e3f5..ee5551e3cc 100644 --- a/xen/arch/arm/include/asm/llc-coloring.h +++ b/xen/arch/arm/include/asm/llc-coloring.h @@ -14,6 +14,7 @@ #include <xen/init.h> bool __init llc_coloring_init(void); +int dom0_set_llc_colors(struct domain *d); #endif /* __ASM_ARM_COLORING_H__ */ diff --git a/xen/arch/arm/llc-coloring.c b/xen/arch/arm/llc-coloring.c index 37d647f038..5ce58aba70 100644 --- a/xen/arch/arm/llc-coloring.c +++ b/xen/arch/arm/llc-coloring.c @@ -26,6 +26,63 @@ size_param("llc-way-size", llc_way_size); /* Number of colors available in the LLC */ static unsigned int __ro_after_init nr_colors = CONFIG_NR_LLC_COLORS; +static unsigned int __ro_after_init dom0_colors[CONFIG_NR_LLC_COLORS]; +static unsigned int __ro_after_init dom0_num_colors; + +/* + * Parse the coloring configuration given in the buf string, following the + * syntax below. + * + * COLOR_CONFIGURATION ::= COLOR | RANGE,...,COLOR | RANGE + * RANGE ::= COLOR-COLOR + * + * Example: "0,2-6,15-16" represents the set of colors: 0,2,3,4,5,6,15,16. + */ +static int parse_color_config(const char *buf, unsigned int *colors, + unsigned int *num_colors) +{ + const char *s = buf; + + if ( !colors || !num_colors ) + return -EINVAL; + + *num_colors = 0; + + while ( *s != '\0' ) + { + if ( *s != ',' ) + { + unsigned int color, start, end; + + start = simple_strtoul(s, &s, 0); + + if ( *s == '-' ) /* Range */ + { + s++; + end = simple_strtoul(s, &s, 0); + } + else /* Single value */ + end = start; + + if ( start > end || (end - start) > UINT_MAX - *num_colors || + *num_colors + (end - start) >= nr_colors ) + return -EINVAL; + for ( color = start; color <= end; color++ ) + colors[(*num_colors)++] = color; + } + else + s++; + } + + return *s ? -EINVAL : 0; +} + +static int __init parse_dom0_colors(const char *s) +{ + return parse_color_config(s, dom0_colors, &dom0_num_colors); +} +custom_param("dom0-llc-colors", parse_dom0_colors); + /* Return the LLC way size by probing the hardware */ static unsigned int __init get_llc_way_size(void) { @@ -102,6 +159,28 @@ static void dump_coloring_info(unsigned char key) printk("Number of LLC colors supported: %u\n", nr_colors); } +static bool check_colors(unsigned int *colors, unsigned int num_colors) +{ + unsigned int i; + + if ( num_colors > nr_colors ) + { + printk(XENLOG_ERR "Number of LLC colors requested > %u\n", nr_colors); + return false; + } + + for ( i = 0; i < num_colors; i++ ) + { + if ( colors[i] >= nr_colors ) + { + printk(XENLOG_ERR "LLC color %u >= %u\n", colors[i], nr_colors); + return false; + } + } + + return true; +} + bool __init llc_coloring_init(void) { if ( !llc_way_size && !(llc_way_size = get_llc_way_size()) ) @@ -150,6 +229,55 @@ void domain_dump_llc_colors(struct domain *d) print_colors(d->llc_colors, d->num_llc_colors); } +static int domain_alloc_colors(struct domain *d, unsigned int num_colors) +{ + d->num_llc_colors = num_colors; + + if ( !num_colors ) + return 0; + + d->llc_colors = xmalloc_array(unsigned int, num_colors); + if ( !d->llc_colors ) + { + printk("Can't allocate LLC colors for domain %pd\n", d); + return -1; + } + + return 0; +} + +static int domain_check_colors(struct domain *d) +{ + unsigned int i; + + if ( !d->num_llc_colors ) + { + printk(XENLOG_WARNING + "LLC color config not found for %pd. Using default\n", d); + if ( domain_alloc_colors(d, nr_colors) ) + return -ENOMEM; + for ( i = 0; i < nr_colors; i++ ) + d->llc_colors[i] = i; + } + else if ( !check_colors(d->llc_colors, d->num_llc_colors) ) + { + printk(XENLOG_ERR "Bad LLC color config for %pd\n", d); + return -EINVAL; + } + + return 0; +} + +int dom0_set_llc_colors(struct domain *d) +{ + if ( domain_alloc_colors(d, dom0_num_colors) ) + return -ENOMEM; + + memcpy(d->llc_colors, dom0_colors, sizeof(unsigned int) * dom0_num_colors); + + return domain_check_colors(d); +} + /* * Local variables: * mode: C -- 2.34.1