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[95.230.250.178]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-aa20df4e7bfsm655228166b.42.2024.11.19.06.13.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Nov 2024 06:13:34 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 76edd0eb-a680-11ef-99a3-01e77a169b0f X-Custom-Connection: eyJyZW1vdGVpcCI6IjJhMDA6MTQ1MDo0ODY0OjIwOjo2MzAiLCJoZWxvIjoibWFpbC1lajEteDYzMC5nb29nbGUuY29tIn0= X-Custom-Transaction: eyJpZCI6Ijc2ZWRkMGViLWE2ODAtMTFlZi05OWEzLTAxZTc3YTE2OWIwZiIsInRzIjoxNzMyMDI1NjE1LjQ4MDIyNiwic2VuZGVyIjoiY2FybG8ubm9uYXRvQG1pbmVydmFzeXMudGVjaCIsInJlY2lwaWVudCI6Inhlbi1kZXZlbEBsaXN0cy54ZW5wcm9qZWN0Lm9yZyJ9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=minervasys-tech.20230601.gappssmtp.com; s=20230601; t=1732025615; x=1732630415; darn=lists.xenproject.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ZZ0Mqo/VVVpodAnrCuD1RTBLK1YlIRTEt2DutSu9Zdo=; b=vTzq1uGNqGgh8V1tSlrGUWNrlX55A5fLwVnzuhTzjxC16mEk3ENOB0po7s9C2QWMgB VZxlIAZdiiLak8B7LvC/K9tAcrpuxm80Hr7BWNt/zklcWtu5hYUQ++1pAbe0miipRlMY 3VqGMjaXHN+1Io9iSAtTM8CAzgFb7+evP0nr6g2pOApkXYIH11ZyrtmYleyd0v32KcFA EJCke2ZZEJyYCfAKMKtlkpumKouT38ZBso3rLBypbW546c0d7IqiP0FLT+vAIwk9i7NN FAY/ghUps+S0MjxPQgIlD/JRJMZMSOQNb5BtlpPoxr6F8yLInqgdj5NGkXUrf1862p/N SdOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732025615; x=1732630415; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ZZ0Mqo/VVVpodAnrCuD1RTBLK1YlIRTEt2DutSu9Zdo=; b=gFvYIRfeMTRbRJUjIGxTBaLQKmrZXbRIfTQyH3S7vGmrWrWno8OvFjZP5BxKa3h5X9 rC+tWx3vsQseFI+OMfrVEc2WvUKBi0FpWD3txInE556ivUSleOUCcESivq8QoHGZEHS3 kzLdahKb6XIoIgIDlUCfQH6NMX3fbGRjZJebLSeeyklPycxDtUxyoLehkNQrT+H/412G Ww95Q2NxoZLA+vX8+MnUwhJUOzoZmkqyRzdXfmTa+v93+8CDDVUIGDmddDzdDZ3z8wAL LuzC4mG9T6urkoFDcCHLhAve70tKZ/2f6EW5w00rgXX7erStBtTay6w5zbsTBCy8RLo0 xdcA== X-Gm-Message-State: AOJu0Yz7Uw91Nwjjj5CpLW+wVxEFrpMp8hagNwRHDCCKa15Me80s6q8H IomhAEzjI47/W9IDyv0ykcVlB5GNDT138ZeO1V7DRCatIEYx0f0UwqgfHYiLStO8ec1doT8vNHQ u X-Google-Smtp-Source: AGHT+IET27SpmU1fFtZs0y0db25/+nd5qOZnnd+Rz1y7eohCrN5Gl7QJHDmK6KH6QMxOO3LdODhs5Q== X-Received: by 2002:a17:907:3689:b0:a9e:8612:eeca with SMTP id a640c23a62f3a-aa48352b54bmr1502734566b.48.1732025614626; Tue, 19 Nov 2024 06:13:34 -0800 (PST) From: Carlo Nonato To: xen-devel@lists.xenproject.org Cc: andrea.bastoni@minervasys.tech, marco.solieri@minervasys.tech, Carlo Nonato , Andrew Cooper , Jan Beulich , Julien Grall , Stefano Stabellini , Bertrand Marquis , Michal Orzel , Volodymyr Babchuk Subject: [PATCH v10 02/12] xen/arm: add initial support for LLC coloring on arm64 Date: Tue, 19 Nov 2024 15:13:19 +0100 Message-ID: <20241119141329.44221-3-carlo.nonato@minervasys.tech> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241119141329.44221-1-carlo.nonato@minervasys.tech> References: <20241119141329.44221-1-carlo.nonato@minervasys.tech> MIME-Version: 1.0 LLC coloring needs to know the last level cache layout in order to make the best use of it. This can be probed by inspecting the CLIDR_EL1 register, so the Last Level is defined as the last level visible by this register. Note that this excludes system caches in some platforms. Static memory allocation and cache coloring are incompatible because static memory can't be guaranteed to use only colors assigned to the domain. Panic during DomUs creation when both are enabled. Based on original work from: Luca Miccio Signed-off-by: Carlo Nonato Signed-off-by: Marco Solieri --- v10: - moved CONFIG_NUMA check in arch/arm/Kconfig v9: - no changes v8: - no changes v7: - only minor changes v6: - get_llc_way_size() now checks for at least separate I/D caches v5: - used - instead of _ for filenames - moved static-mem check in this patch - moved dom0 colors parsing in next patch - moved color allocation and configuration in next patch - moved check_colors() in next patch - colors are now printed in short form v4: - added "llc-coloring" cmdline option for the boot-time switch - dom0 colors are now checked during domain init as for any other domain - fixed processor.h masks bit width - check for overflow in parse_color_config() - check_colors() now checks also that colors are sorted and unique --- docs/misc/cache-coloring.rst | 14 +++++ xen/arch/arm/Kconfig | 1 + xen/arch/arm/Makefile | 1 + xen/arch/arm/dom0less-build.c | 6 +++ xen/arch/arm/include/asm/processor.h | 16 ++++++ xen/arch/arm/llc-coloring.c | 78 ++++++++++++++++++++++++++++ xen/arch/arm/setup.c | 3 ++ xen/common/llc-coloring.c | 2 +- xen/include/xen/llc-coloring.h | 4 ++ 9 files changed, 124 insertions(+), 1 deletion(-) create mode 100644 xen/arch/arm/llc-coloring.c diff --git a/docs/misc/cache-coloring.rst b/docs/misc/cache-coloring.rst index 0fe3830c40..b608284e9b 100644 --- a/docs/misc/cache-coloring.rst +++ b/docs/misc/cache-coloring.rst @@ -111,6 +111,20 @@ Auto-probing of LLC specs LLC size and number of ways are probed automatically by default. +In the Arm implementation, this is done by inspecting the CLIDR_EL1 register. +This means that other system caches that aren't visible there are ignored. + LLC specs can be manually set via the above command line parameters. This bypasses any auto-probing and it's used to overcome failing situations, such as flawed probing logic, or for debugging/testing purposes. + +Known issues and limitations +**************************** + +"xen,static-mem" isn't supported when coloring is enabled +######################################################### + +In the domain configuration, "xen,static-mem" allows memory to be statically +allocated to the domain. This isn't possible when LLC coloring is enabled, +because that memory can't be guaranteed to use only colors assigned to the +domain. diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig index 15b2e4a227..7f0712e674 100644 --- a/xen/arch/arm/Kconfig +++ b/xen/arch/arm/Kconfig @@ -8,6 +8,7 @@ config ARM_64 depends on !ARM_32 select 64BIT select HAS_FAST_MULTIPLY + select HAS_LLC_COLORING if !NUMA config ARM def_bool y diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile index e4ad1ce851..ccbfc61f88 100644 --- a/xen/arch/arm/Makefile +++ b/xen/arch/arm/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_IOREQ_SERVER) += ioreq.o obj-y += irq.o obj-y += kernel.init.o obj-$(CONFIG_LIVEPATCH) += livepatch.o +obj-$(CONFIG_LLC_COLORING) += llc-coloring.o obj-$(CONFIG_MEM_ACCESS) += mem_access.o obj-y += mm.o obj-y += monitor.o diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c index f328a044e9..d93a85434e 100644 --- a/xen/arch/arm/dom0less-build.c +++ b/xen/arch/arm/dom0less-build.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -890,7 +891,12 @@ void __init create_domUs(void) panic("No more domain IDs available\n"); if ( dt_find_property(node, "xen,static-mem", NULL) ) + { + if ( llc_coloring_enabled ) + panic("LLC coloring and static memory are incompatible\n"); + flags |= CDF_staticmem; + } if ( dt_property_read_bool(node, "direct-map") ) { diff --git a/xen/arch/arm/include/asm/processor.h b/xen/arch/arm/include/asm/processor.h index 8e02410465..ef33ea198c 100644 --- a/xen/arch/arm/include/asm/processor.h +++ b/xen/arch/arm/include/asm/processor.h @@ -18,6 +18,22 @@ #define CTR_IDC_SHIFT 28 #define CTR_DIC_SHIFT 29 +/* CCSIDR Current Cache Size ID Register */ +#define CCSIDR_LINESIZE_MASK _AC(0x7, UL) +#define CCSIDR_NUMSETS_SHIFT 13 +#define CCSIDR_NUMSETS_MASK _AC(0x3fff, UL) +#define CCSIDR_NUMSETS_SHIFT_FEAT_CCIDX 32 +#define CCSIDR_NUMSETS_MASK_FEAT_CCIDX _AC(0xffffff, UL) + +/* CSSELR Cache Size Selection Register */ +#define CSSELR_LEVEL_MASK _AC(0x7, UL) +#define CSSELR_LEVEL_SHIFT 1 + +/* CLIDR Cache Level ID Register */ +#define CLIDR_CTYPEn_SHIFT(n) (3 * ((n) - 1)) +#define CLIDR_CTYPEn_MASK _AC(0x7, UL) +#define CLIDR_CTYPEn_LEVELS 7 + #define ICACHE_POLICY_VPIPT 0 #define ICACHE_POLICY_AIVIVT 1 #define ICACHE_POLICY_VIPT 2 diff --git a/xen/arch/arm/llc-coloring.c b/xen/arch/arm/llc-coloring.c new file mode 100644 index 0000000000..a7e0907816 --- /dev/null +++ b/xen/arch/arm/llc-coloring.c @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Last Level Cache (LLC) coloring support for ARM + * + * Copyright (C) 2024, Advanced Micro Devices, Inc. + * Copyright (C) 2024, Minerva Systems SRL + */ +#include +#include + +#include +#include + +/* Return the LLC way size by probing the hardware */ +unsigned int __init get_llc_way_size(void) +{ + register_t ccsidr_el1; + register_t clidr_el1 = READ_SYSREG(CLIDR_EL1); + register_t csselr_el1 = READ_SYSREG(CSSELR_EL1); + register_t id_aa64mmfr2_el1 = READ_SYSREG(ID_AA64MMFR2_EL1); + uint32_t ccsidr_numsets_shift = CCSIDR_NUMSETS_SHIFT; + uint32_t ccsidr_numsets_mask = CCSIDR_NUMSETS_MASK; + unsigned int n, line_size, num_sets; + + for ( n = CLIDR_CTYPEn_LEVELS; n != 0; n-- ) + { + uint8_t ctype_n = (clidr_el1 >> CLIDR_CTYPEn_SHIFT(n)) & + CLIDR_CTYPEn_MASK; + + /* Unified cache (see Arm ARM DDI 0487J.a D19.2.27) */ + if ( ctype_n == 0b100 ) + break; + } + + if ( n == 0 ) + return 0; + + WRITE_SYSREG((n - 1) << CSSELR_LEVEL_SHIFT, CSSELR_EL1); + isb(); + + ccsidr_el1 = READ_SYSREG(CCSIDR_EL1); + + /* Arm ARM: (Log2(Number of bytes in cache line)) - 4 */ + line_size = 1U << ((ccsidr_el1 & CCSIDR_LINESIZE_MASK) + 4); + + /* If FEAT_CCIDX is enabled, CCSIDR_EL1 has a different bit layout */ + if ( (id_aa64mmfr2_el1 >> ID_AA64MMFR2_CCIDX_SHIFT) & 0x7 ) + { + ccsidr_numsets_shift = CCSIDR_NUMSETS_SHIFT_FEAT_CCIDX; + ccsidr_numsets_mask = CCSIDR_NUMSETS_MASK_FEAT_CCIDX; + } + + /* Arm ARM: (Number of sets in cache) - 1 */ + num_sets = ((ccsidr_el1 >> ccsidr_numsets_shift) & ccsidr_numsets_mask) + 1; + + printk(XENLOG_INFO "LLC found: L%u (line size: %u bytes, sets num: %u)\n", + n, line_size, num_sets); + + /* Restore value in CSSELR_EL1 */ + WRITE_SYSREG(csselr_el1, CSSELR_EL1); + isb(); + + return line_size * num_sets; +} + +void __init arch_llc_coloring_init(void) +{ +} + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index 71ebaa77ca..84fecaabea 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -326,6 +327,8 @@ void asmlinkage __init start_xen(unsigned long fdt_paddr) printk("Command line: %s\n", cmdline); cmdline_parse(cmdline); + llc_coloring_init(); + setup_mm(); vm_init(); diff --git a/xen/common/llc-coloring.c b/xen/common/llc-coloring.c index 29b75e0e0d..45b001b105 100644 --- a/xen/common/llc-coloring.c +++ b/xen/common/llc-coloring.c @@ -11,7 +11,7 @@ #define NR_LLC_COLORS (1U << CONFIG_LLC_COLORS_ORDER) -static bool __ro_after_init llc_coloring_enabled; +bool __ro_after_init llc_coloring_enabled; boolean_param("llc-coloring", llc_coloring_enabled); static unsigned int __initdata llc_size; diff --git a/xen/include/xen/llc-coloring.h b/xen/include/xen/llc-coloring.h index 6ccf4613c2..ad2525e153 100644 --- a/xen/include/xen/llc-coloring.h +++ b/xen/include/xen/llc-coloring.h @@ -12,10 +12,14 @@ #include #ifdef CONFIG_LLC_COLORING +extern bool llc_coloring_enabled; + void llc_coloring_init(void); void dump_llc_coloring_info(void); void domain_dump_llc_colors(const struct domain *d); #else +#define llc_coloring_enabled false + static inline void llc_coloring_init(void) {} static inline void dump_llc_coloring_info(void) {} static inline void domain_dump_llc_colors(const struct domain *d) {}