diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-08-03 21:53:27 -1000 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-08-03 21:53:27 -1000 |
commit | c0c770e610cc4cdcd66c7e939bdf89cc3e72f79d (patch) | |
tree | 7cf6807258fef2a85a2ff212f4f4eb6d9dc336c6 | |
parent | a9e4e6e14c322e08d1c615afc8f504fb415f9613 (diff) | |
parent | d0e323b47057f4492b8fa22345f38d80a469bf8d (diff) | |
download | op-kernel-dev-c0c770e610cc4cdcd66c7e939bdf89cc3e72f79d.zip op-kernel-dev-c0c770e610cc4cdcd66c7e939bdf89cc3e72f79d.tar.gz |
Merge branch 'apei-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'apei-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
ACPI, APEI, EINJ Param support is disabled by default
APEI GHES: 32-bit buildfix
ACPI: APEI build fix
ACPI, APEI, GHES: Add hardware memory error recovery support
HWPoison: add memory_failure_queue()
ACPI, APEI, GHES, Error records content based throttle
ACPI, APEI, GHES, printk support for recoverable error via NMI
lib, Make gen_pool memory allocator lockless
lib, Add lock-less NULL terminated single list
Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG
ACPI, APEI, Add WHEA _OSC support
ACPI, APEI, Add APEI bit support in generic _OSC call
ACPI, APEI, GHES, Support disable GHES at boot time
ACPI, APEI, GHES, Prevent GHES to be built as module
ACPI, APEI, Use apei_exec_run_optional in APEI EINJ and ERST
ACPI, APEI, Add apei_exec_run_optional
ACPI, APEI, GHES, Do not ratelimit fatal error printk before panic
ACPI, APEI, ERST, Fix erst-dbg long record reading issue
ACPI, APEI, ERST, Prevent erst_dbg from loading if ERST is disabled
35 files changed, 1172 insertions, 135 deletions
diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/acpi/apei/einj.txt index dfab718..5cc699b 100644 --- a/Documentation/acpi/apei/einj.txt +++ b/Documentation/acpi/apei/einj.txt @@ -48,12 +48,19 @@ directory apei/einj. The following files are provided. - param1 This file is used to set the first error parameter value. Effect of parameter depends on error_type specified. For memory error, this is - physical memory address. + physical memory address. Only available if param_extension module + parameter is specified. - param2 This file is used to set the second error parameter value. Effect of parameter depends on error_type specified. For memory error, this is - physical memory address mask. + physical memory address mask. Only available if param_extension + module parameter is specified. + +Injecting parameter support is a BIOS version specific extension, that +is, it only works on some BIOS version. If you want to use it, please +make sure your BIOS version has the proper support and specify +"param_extension=y" in module parameter. For more information about EINJ, please refer to ACPI specification version 4.0, section 17.5. diff --git a/arch/Kconfig b/arch/Kconfig index 26b0e23..4b0669c 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -178,4 +178,7 @@ config HAVE_ARCH_MUTEX_CPU_RELAX config HAVE_RCU_TABLE_FREE bool +config ARCH_HAVE_NMI_SAFE_CMPXCHG + bool + source "kernel/gcov/Kconfig" diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index ca2da8d..60cde53 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -14,6 +14,7 @@ config ALPHA select AUTO_IRQ_AFFINITY if SMP select GENERIC_IRQ_SHOW select ARCH_WANT_OPTIONAL_GPIOLIB + select ARCH_HAVE_NMI_SAFE_CMPXCHG help The Alpha is a 64-bit general-purpose processor designed and marketed by the Digital Equipment Corporation of blessed memory, diff --git a/arch/avr32/Kconfig b/arch/avr32/Kconfig index e9d689b..197e96f 100644 --- a/arch/avr32/Kconfig +++ b/arch/avr32/Kconfig @@ -10,6 +10,7 @@ config AVR32 select GENERIC_IRQ_PROBE select HARDIRQS_SW_RESEND select GENERIC_IRQ_SHOW + select ARCH_HAVE_NMI_SAFE_CMPXCHG help AVR32 is a high-performance 32-bit RISC microprocessor core, designed for cost-sensitive embedded applications, with particular diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig index cb884e4..bad27a6 100644 --- a/arch/frv/Kconfig +++ b/arch/frv/Kconfig @@ -7,6 +7,7 @@ config FRV select HAVE_PERF_EVENTS select HAVE_GENERIC_HARDIRQS select GENERIC_IRQ_SHOW + select ARCH_HAVE_NMI_SAFE_CMPXCHG config ZONE_DMA bool diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 64c7ab7..1248547 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -28,6 +28,7 @@ config IA64 select IRQ_PER_CPU select GENERIC_IRQ_SHOW select ARCH_WANT_OPTIONAL_GPIOLIB + select ARCH_HAVE_NMI_SAFE_CMPXCHG default y help The Itanium Processor Family is Intel's 64-bit successor to diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 284cd37..9e8ee9d 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -6,6 +6,7 @@ config M68K select GENERIC_ATOMIC64 if MMU select HAVE_GENERIC_HARDIRQS if !MMU select GENERIC_IRQ_SHOW if !MMU + select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS config RWSEM_GENERIC_SPINLOCK bool diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 65adc86..e077b0b 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -15,6 +15,7 @@ config PARISC select HAVE_GENERIC_HARDIRQS select GENERIC_IRQ_PROBE select IRQ_PER_CPU + select ARCH_HAVE_NMI_SAFE_CMPXCHG help The PA-RISC microprocessor is designed by Hewlett-Packard and used diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 374c475..6926b61 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -136,6 +136,7 @@ config PPC select HAVE_SYSCALL_TRACEPOINTS select HAVE_BPF_JIT if (PPC64 && NET) select HAVE_ARCH_JUMP_LABEL + select ARCH_HAVE_NMI_SAFE_CMPXCHG config EARLY_PRINTK bool diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index c03fef7..0f98bbd 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -81,6 +81,7 @@ config S390 select INIT_ALL_POSSIBLE select HAVE_IRQ_WORK select HAVE_PERF_EVENTS + select ARCH_HAVE_NMI_SAFE_CMPXCHG select HAVE_KERNEL_GZIP select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_LZMA diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index 748ff19..ff9177c 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -11,6 +11,7 @@ config SUPERH select HAVE_DMA_ATTRS select HAVE_IRQ_WORK select HAVE_PERF_EVENTS + select ARCH_HAVE_NMI_SAFE_CMPXCHG if (GUSA_RB || CPU_SH4A) select PERF_USE_VMALLOC select HAVE_KERNEL_GZIP select HAVE_KERNEL_BZIP2 diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 1074ddd..42c67be 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -54,6 +54,7 @@ config SPARC64 select HAVE_PERF_EVENTS select PERF_USE_VMALLOC select IRQ_PREFLOW_FASTEOI + select ARCH_HAVE_NMI_SAFE_CMPXCHG config ARCH_DEFCONFIG string diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 0249b8b..b30f71a 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -12,6 +12,7 @@ config TILE select GENERIC_PENDING_IRQ if SMP select GENERIC_IRQ_SHOW select SYS_HYPERVISOR + select ARCH_HAVE_NMI_SAFE_CMPXCHG if !M386 # FIXME: investigate whether we need/want these options. # select HAVE_IOREMAP_PROT diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7cf916f..6a47bb2 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -72,6 +72,7 @@ config X86 select USE_GENERIC_SMP_HELPERS if SMP select HAVE_BPF_JIT if (X86_64 && NET) select CLKEVT_I8253 + select ARCH_HAVE_NMI_SAFE_CMPXCHG config INSTRUCTION_DECODER def_bool (KPROBES || PERF_EVENTS) diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig index f739a70..c34aa51 100644 --- a/drivers/acpi/apei/Kconfig +++ b/drivers/acpi/apei/Kconfig @@ -10,9 +10,11 @@ config ACPI_APEI error injection. config ACPI_APEI_GHES - tristate "APEI Generic Hardware Error Source" + bool "APEI Generic Hardware Error Source" depends on ACPI_APEI && X86 select ACPI_HED + select LLIST + select GENERIC_ALLOCATOR help Generic Hardware Error Source provides a way to report platform hardware errors (such as that from chipset). It @@ -30,6 +32,13 @@ config ACPI_APEI_PCIEAER PCIe AER errors may be reported via APEI firmware first mode. Turn on this option to enable the corresponding support. +config ACPI_APEI_MEMORY_FAILURE + bool "APEI memory error recovering support" + depends on ACPI_APEI && MEMORY_FAILURE + help + Memory errors may be reported via APEI firmware first mode. + Turn on this option to enable the memory recovering support. + config ACPI_APEI_EINJ tristate "APEI Error INJection (EINJ)" depends on ACPI_APEI && DEBUG_FS diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c index 4a904a4..8041248 100644 --- a/drivers/acpi/apei/apei-base.c +++ b/drivers/acpi/apei/apei-base.c @@ -157,9 +157,10 @@ EXPORT_SYMBOL_GPL(apei_exec_noop); * Interpret the specified action. Go through whole action table, * execute all instructions belong to the action. */ -int apei_exec_run(struct apei_exec_context *ctx, u8 action) +int __apei_exec_run(struct apei_exec_context *ctx, u8 action, + bool optional) { - int rc; + int rc = -ENOENT; u32 i, ip; struct acpi_whea_header *entry; apei_exec_ins_func_t run; @@ -198,9 +199,9 @@ rewind: goto rewind; } - return 0; + return !optional && rc < 0 ? rc : 0; } -EXPORT_SYMBOL_GPL(apei_exec_run); +EXPORT_SYMBOL_GPL(__apei_exec_run); typedef int (*apei_exec_entry_func_t)(struct apei_exec_context *ctx, struct acpi_whea_header *entry, @@ -603,3 +604,29 @@ struct dentry *apei_get_debugfs_dir(void) return dapei; } EXPORT_SYMBOL_GPL(apei_get_debugfs_dir); + +int apei_osc_setup(void) +{ + static u8 whea_uuid_str[] = "ed855e0c-6c90-47bf-a62a-26de0fc5ad5c"; + acpi_handle handle; + u32 capbuf[3]; + struct acpi_osc_context context = { + .uuid_str = whea_uuid_str, + .rev = 1, + .cap.length = sizeof(capbuf), + .cap.pointer = capbuf, + }; + + capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE; + capbuf[OSC_SUPPORT_TYPE] = 0; + capbuf[OSC_CONTROL_TYPE] = 0; + + if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)) + || ACPI_FAILURE(acpi_run_osc(handle, &context))) + return -EIO; + else { + kfree(context.ret.pointer); + return 0; + } +} +EXPORT_SYMBOL_GPL(apei_osc_setup); diff --git a/drivers/acpi/apei/apei-internal.h b/drivers/acpi/apei/apei-internal.h index ef0581f..f57050e 100644 --- a/drivers/acpi/apei/apei-internal.h +++ b/drivers/acpi/apei/apei-internal.h @@ -50,7 +50,18 @@ static inline u64 apei_exec_ctx_get_output(struct apei_exec_context *ctx) return ctx->value; } -int apei_exec_run(struct apei_exec_context *ctx, u8 action); +int __apei_exec_run(struct apei_exec_context *ctx, u8 action, bool optional); + +static inline int apei_exec_run(struct apei_exec_context *ctx, u8 action) +{ + return __apei_exec_run(ctx, action, 0); +} + +/* It is optional whether the firmware provides the action */ +static inline int apei_exec_run_optional(struct apei_exec_context *ctx, u8 action) +{ + return __apei_exec_run(ctx, action, 1); +} /* Common instruction implementation */ @@ -113,4 +124,6 @@ void apei_estatus_print(const char *pfx, const struct acpi_hest_generic_status *estatus); int apei_estatus_check_header(const struct acpi_hest_generic_status *estatus); int apei_estatus_check(const struct acpi_hest_generic_status *estatus); + +int apei_osc_setup(void); #endif diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c index f74b2ea..589b96c 100644 --- a/drivers/acpi/apei/einj.c +++ b/drivers/acpi/apei/einj.c @@ -46,7 +46,8 @@ * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the * EINJ table through an unpublished extension. Use with caution as * most will ignore the parameter and make their own choice of address - * for error injection. + * for error injection. This extension is used only if + * param_extension module parameter is specified. */ struct einj_parameter { u64 type; @@ -65,6 +66,9 @@ struct einj_parameter { ((struct acpi_whea_header *)((char *)(tab) + \ sizeof(struct acpi_table_einj))) +static bool param_extension; +module_param(param_extension, bool, 0); + static struct acpi_table_einj *einj_tab; static struct apei_resources einj_resources; @@ -285,7 +289,7 @@ static int __einj_error_inject(u32 type, u64 param1, u64 param2) einj_exec_ctx_init(&ctx); - rc = apei_exec_run(&ctx, ACPI_EINJ_BEGIN_OPERATION); + rc = apei_exec_run_optional(&ctx, ACPI_EINJ_BEGIN_OPERATION); if (rc) return rc; apei_exec_ctx_set_input(&ctx, type); @@ -323,7 +327,7 @@ static int __einj_error_inject(u32 type, u64 param1, u64 param2) rc = __einj_error_trigger(trigger_paddr); if (rc) return rc; - rc = apei_exec_run(&ctx, ACPI_EINJ_END_OPERATION); + rc = apei_exec_run_optional(&ctx, ACPI_EINJ_END_OPERATION); return rc; } @@ -489,14 +493,6 @@ static int __init einj_init(void) einj_debug_dir, NULL, &error_type_fops); if (!fentry) goto err_cleanup; - fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR, - einj_debug_dir, &error_param1); - if (!fentry) - goto err_cleanup; - fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR, - einj_debug_dir, &error_param2); - if (!fentry) - goto err_cleanup; fentry = debugfs_create_file("error_inject", S_IWUSR, einj_debug_dir, NULL, &error_inject_fops); if (!fentry) @@ -513,12 +509,23 @@ static int __init einj_init(void) rc = apei_exec_pre_map_gars(&ctx); if (rc) goto err_release; - param_paddr = einj_get_parameter_address(); - if (param_paddr) { - einj_param = ioremap(param_paddr, sizeof(*einj_param)); - rc = -ENOMEM; - if (!einj_param) - goto err_unmap; + if (param_extension) { + param_paddr = einj_get_parameter_address(); + if (param_paddr) { + einj_param = ioremap(param_paddr, sizeof(*einj_param)); + rc = -ENOMEM; + if (!einj_param) + goto err_unmap; + fentry = debugfs_create_x64("param1", S_IRUSR | S_IWUSR, + einj_debug_dir, &error_param1); + if (!fentry) + goto err_unmap; + fentry = debugfs_create_x64("param2", S_IRUSR | S_IWUSR, + einj_debug_dir, &error_param2); + if (!fentry) + goto err_unmap; + } else + pr_warn(EINJ_PFX "Parameter extension is not supported.\n"); } pr_info(EINJ_PFX "Error INJection is initialized.\n"); @@ -526,6 +533,8 @@ static int __init einj_init(void) return 0; err_unmap: + if (einj_param) + iounmap(einj_param); apei_exec_post_unmap_gars(&ctx); err_release: apei_resources_release(&einj_resources); diff --git a/drivers/acpi/apei/erst-dbg.c b/drivers/acpi/apei/erst-dbg.c index a4cfb64..903549d 100644 --- a/drivers/acpi/apei/erst-dbg.c +++ b/drivers/acpi/apei/erst-dbg.c @@ -33,7 +33,7 @@ #define ERST_DBG_PFX "ERST DBG: " -#define ERST_DBG_RECORD_LEN_MAX 4096 +#define ERST_DBG_RECORD_LEN_MAX 0x4000 static void *erst_dbg_buf; static unsigned int erst_dbg_buf_len; @@ -213,6 +213,10 @@ static struct miscdevice erst_dbg_dev = { static __init int erst_dbg_init(void) { + if (erst_disable) { + pr_info(ERST_DBG_PFX "ERST support is disabled.\n"); + return -ENODEV; + } return misc_register(&erst_dbg_dev); } diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index 6053f47..2ca59dc 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -642,7 +642,7 @@ static int __erst_write_to_storage(u64 offset) int rc; erst_exec_ctx_init(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_BEGIN_WRITE); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_WRITE); if (rc) return rc; apei_exec_ctx_set_input(&ctx, offset); @@ -666,7 +666,7 @@ static int __erst_write_to_storage(u64 offset) if (rc) return rc; val = apei_exec_ctx_get_output(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_END); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); if (rc) return rc; @@ -681,7 +681,7 @@ static int __erst_read_from_storage(u64 record_id, u64 offset) int rc; erst_exec_ctx_init(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_BEGIN_READ); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_READ); if (rc) return rc; apei_exec_ctx_set_input(&ctx, offset); @@ -709,7 +709,7 @@ static int __erst_read_from_storage(u64 record_id, u64 offset) if (rc) return rc; val = apei_exec_ctx_get_output(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_END); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); if (rc) return rc; @@ -724,7 +724,7 @@ static int __erst_clear_from_storage(u64 record_id) int rc; erst_exec_ctx_init(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_BEGIN_CLEAR); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_BEGIN_CLEAR); if (rc) return rc; apei_exec_ctx_set_input(&ctx, record_id); @@ -748,7 +748,7 @@ static int __erst_clear_from_storage(u64 record_id) if (rc) return rc; val = apei_exec_ctx_get_output(&ctx); - rc = apei_exec_run(&ctx, ACPI_ERST_END); + rc = apei_exec_run_optional(&ctx, ACPI_ERST_END); if (rc) return rc; diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index f703b28..0784f99 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -12,7 +12,7 @@ * For more information about Generic Hardware Error Source, please * refer to ACPI Specification version 4.0, section 17.3.2.6 * - * Copyright 2010 Intel Corp. + * Copyright 2010,2011 Intel Corp. * Author: Huang Ying <ying.huang@intel.com> * * This program is free software; you can redistribute it and/or @@ -42,6 +42,9 @@ #include <linux/mutex.h> #include <linux/ratelimit.h> #include <linux/vmalloc.h> +#include <linux/irq_work.h> +#include <linux/llist.h> +#include <linux/genalloc.h> #include <acpi/apei.h> #include <acpi/atomicio.h> #include <acpi/hed.h> @@ -53,6 +56,30 @@ #define GHES_PFX "GHES: " #define GHES_ESTATUS_MAX_SIZE 65536 +#define GHES_ESOURCE_PREALLOC_MAX_SIZE 65536 + +#define GHES_ESTATUS_POOL_MIN_ALLOC_ORDER 3 + +/* This is just an estimation for memory pool allocation */ +#define GHES_ESTATUS_CACHE_AVG_SIZE 512 + +#define GHES_ESTATUS_CACHES_SIZE 4 + +#define GHES_ESTATUS_IN_CACHE_MAX_NSEC 10000000000ULL +/* Prevent too many caches are allocated because of RCU */ +#define GHES_ESTATUS_CACHE_ALLOCED_MAX (GHES_ESTATUS_CACHES_SIZE * 3 / 2) + +#define GHES_ESTATUS_CACHE_LEN(estatus_len) \ + (sizeof(struct ghes_estatus_cache) + (estatus_len)) +#define GHES_ESTATUS_FROM_CACHE(estatus_cache) \ + ((struct acpi_hest_generic_status *) \ + ((struct ghes_estatus_cache *)(estatus_cache) + 1)) + +#define GHES_ESTATUS_NODE_LEN(estatus_len) \ + (sizeof(struct ghes_estatus_node) + (estatus_len)) +#define GHES_ESTATUS_FROM_NODE(estatus_node) \ + ((struct acpi_hest_generic_status *) \ + ((struct ghes_estatus_node *)(estatus_node) + 1)) /* * One struct ghes is created for each generic hardware error source. @@ -77,6 +104,22 @@ struct ghes { }; }; +struct ghes_estatus_node { + struct llist_node llnode; + struct acpi_hest_generic *generic; +}; + +struct ghes_estatus_cache { + u32 estatus_len; + atomic_t count; + struct acpi_hest_generic *generic; + unsigned long long time_in; + struct rcu_head rcu; +}; + +int ghes_disable; +module_param_named(disable, ghes_disable, bool, 0); + static int ghes_panic_timeout __read_mostly = 30; /* @@ -121,6 +164,22 @@ static struct vm_struct *ghes_ioremap_area; static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi); static DEFINE_SPINLOCK(ghes_ioremap_lock_irq); +/* + * printk is not safe in NMI context. So in NMI handler, we allocate + * required memory from lock-less memory allocator + * (ghes_estatus_pool), save estatus into it, put them into lock-less + * list (ghes_estatus_llist), then delay printk into IRQ context via + * irq_work (ghes_proc_irq_work). ghes_estatus_size_request record + * required pool size by all NMI error source. + */ +static struct gen_pool *ghes_estatus_pool; +static unsigned long ghes_estatus_pool_size_request; +static struct llist_head ghes_estatus_llist; +static struct irq_work ghes_proc_irq_work; + +struct ghes_estatus_cache *ghes_estatus_caches[GHES_ESTATUS_CACHES_SIZE]; +static atomic_t ghes_estatus_cache_alloced; + static int ghes_ioremap_init(void) { ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES, @@ -180,6 +239,55 @@ static void ghes_iounmap_irq(void __iomem *vaddr_ptr) __flush_tlb_one(vaddr); } +static int ghes_estatus_pool_init(void) +{ + ghes_estatus_pool = gen_pool_create(GHES_ESTATUS_POOL_MIN_ALLOC_ORDER, -1); + if (!ghes_estatus_pool) + return -ENOMEM; + return 0; +} + +static void ghes_estatus_pool_free_chunk_page(struct gen_pool *pool, + struct gen_pool_chunk *chunk, + void *data) +{ + free_page(chunk->start_addr); +} + +static void ghes_estatus_pool_exit(void) +{ + gen_pool_for_each_chunk(ghes_estatus_pool, + ghes_estatus_pool_free_chunk_page, NULL); + gen_pool_destroy(ghes_estatus_pool); +} + +static int ghes_estatus_pool_expand(unsigned long len) +{ + unsigned long i, pages, size, addr; + int ret; + + ghes_estatus_pool_size_request += PAGE_ALIGN(len); + size = gen_pool_size(ghes_estatus_pool); + if (size >= ghes_estatus_pool_size_request) + return 0; + pages = (ghes_estatus_pool_size_request - size) / PAGE_SIZE; + for (i = 0; i < pages; i++) { + addr = __get_free_page(GFP_KERNEL); + if (!addr) + return -ENOMEM; + ret = gen_pool_add(ghes_estatus_pool, addr, PAGE_SIZE, -1); + if (ret) + return ret; + } + + return 0; +} + +static void ghes_estatus_pool_shrink(unsigned long len) +{ + ghes_estatus_pool_size_request -= PAGE_ALIGN(len); +} + static struct ghes *ghes_new(struct acpi_hest_generic *generic) { struct ghes *ghes; @@ -341,43 +449,196 @@ static void ghes_clear_estatus(struct ghes *ghes) ghes->flags &= ~GHES_TO_CLEAR; } -static void ghes_do_proc(struct ghes *ghes) +static void ghes_do_proc(const struct acpi_hest_generic_status *estatus) { - int sev, processed = 0; + int sev, sec_sev; struct acpi_hest_generic_data *gdata; - sev = ghes_severity(ghes->estatus->error_severity); - apei_estatus_for_each_section(ghes->estatus, gdata) { -#ifdef CONFIG_X86_MCE + sev = ghes_severity(estatus->error_severity); + apei_estatus_for_each_section(estatus, gdata) { + sec_sev = ghes_severity(gdata->error_severity); if (!uuid_le_cmp(*(uuid_le *)gdata->section_type, CPER_SEC_PLATFORM_MEM)) { - apei_mce_report_mem_error( - sev == GHES_SEV_CORRECTED, - (struct cper_sec_mem_err *)(gdata+1)); - processed = 1; - } + struct cper_sec_mem_err *mem_err; + mem_err = (struct cper_sec_mem_err *)(gdata+1); +#ifdef CONFIG_X86_MCE + apei_mce_report_mem_error(sev == GHES_SEV_CORRECTED, + mem_err); #endif +#ifdef CONFIG_ACPI_APEI_MEMORY_FAILURE + if (sev == GHES_SEV_RECOVERABLE && + sec_sev == GHES_SEV_RECOVERABLE && + mem_err->validation_bits & CPER_MEM_VALID_PHYSICAL_ADDRESS) { + unsigned long pfn; + pfn = mem_err->physical_addr >> PAGE_SHIFT; + memory_failure_queue(pfn, 0, 0); + } +#endif + } } } -static void ghes_print_estatus(const char *pfx, struct ghes *ghes) +static void __ghes_print_estatus(const char *pfx, + const struct acpi_hest_generic *generic, + const struct acpi_hest_generic_status *estatus) { - /* Not more than 2 messages every 5 seconds */ - static DEFINE_RATELIMIT_STATE(ratelimit, 5*HZ, 2); - if (pfx == NULL) { - if (ghes_severity(ghes->estatus->error_severity) <= + if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED) pfx = KERN_WARNING HW_ERR; else pfx = KERN_ERR HW_ERR; } - if (__ratelimit(&ratelimit)) { - printk( - "%s""Hardware error from APEI Generic Hardware Error Source: %d\n", - pfx, ghes->generic->header.source_id); - apei_estatus_print(pfx, ghes->estatus); + printk("%s""Hardware error from APEI Generic Hardware Error Source: %d\n", + pfx, generic->header.source_id); + apei_estatus_print(pfx, estatus); +} + +static int ghes_print_estatus(const char *pfx, + const struct acpi_hest_generic *generic, + const struct acpi_hest_generic_status *estatus) +{ + /* Not more than 2 messages every 5 seconds */ + static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); + static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); + struct ratelimit_state *ratelimit; + + if (ghes_severity(estatus->error_severity) <= GHES_SEV_CORRECTED) + ratelimit = &ratelimit_corrected; + else + ratelimit = &ratelimit_uncorrected; + if (__ratelimit(ratelimit)) { + __ghes_print_estatus(pfx, generic, estatus); + return 1; } + return 0; +} + +/* + * GHES error status reporting throttle, to report more kinds of + * errors, instead of just most frequently occurred errors. + */ +static int ghes_estatus_cached(struct acpi_hest_generic_status *estatus) +{ + u32 len; + int i, cached = 0; + unsigned long long now; + struct ghes_estatus_cache *cache; + struct acpi_hest_generic_status *cache_estatus; + + len = apei_estatus_len(estatus); + rcu_read_lock(); + for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { + cache = rcu_dereference(ghes_estatus_caches[i]); + if (cache == NULL) + continue; + if (len != cache->estatus_len) + continue; + cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); + if (memcmp(estatus, cache_estatus, len)) + continue; + atomic_inc(&cache->count); + now = sched_clock(); + if (now - cache->time_in < GHES_ESTATUS_IN_CACHE_MAX_NSEC) + cached = 1; + break; + } + rcu_read_unlock(); + return cached; +} + +static struct ghes_estatus_cache *ghes_estatus_cache_alloc( + struct acpi_hest_generic *generic, + struct acpi_hest_generic_status *estatus) +{ + int alloced; + u32 len, cache_len; + struct ghes_estatus_cache *cache; + struct acpi_hest_generic_status *cache_estatus; + + alloced = atomic_add_return(1, &ghes_estatus_cache_alloced); + if (alloced > GHES_ESTATUS_CACHE_ALLOCED_MAX) { + atomic_dec(&ghes_estatus_cache_alloced); + return NULL; + } + len = apei_estatus_len(estatus); + cache_len = GHES_ESTATUS_CACHE_LEN(len); + cache = (void *)gen_pool_alloc(ghes_estatus_pool, cache_len); + if (!cache) { + atomic_dec(&ghes_estatus_cache_alloced); + return NULL; + } + cache_estatus = GHES_ESTATUS_FROM_CACHE(cache); + memcpy(cache_estatus, estatus, len); + cache->estatus_len = len; + atomic_set(&cache->count, 0); + cache->generic = generic; + cache->time_in = sched_clock(); + return cache; +} + +static void ghes_estatus_cache_free(struct ghes_estatus_cache *cache) +{ + u32 len; + + len = apei_estatus_len(GHES_ESTATUS_FROM_CACHE(cache)); + len = GHES_ESTATUS_CACHE_LEN(len); + gen_pool_free(ghes_estatus_pool, (unsigned long)cache, len); + atomic_dec(&ghes_estatus_cache_alloced); +} + +static void ghes_estatus_cache_rcu_free(struct rcu_head *head) +{ + struct ghes_estatus_cache *cache; + + cache = container_of(head, struct ghes_estatus_cache, rcu); + ghes_estatus_cache_free(cache); +} + +static void ghes_estatus_cache_add( + struct acpi_hest_generic *generic, + struct acpi_hest_generic_status *estatus) +{ + int i, slot = -1, count; + unsigned long long now, duration, period, max_period = 0; + struct ghes_estatus_cache *cache, *slot_cache = NULL, *new_cache; + + new_cache = ghes_estatus_cache_alloc(generic, estatus); + if (new_cache == NULL) + return; + rcu_read_lock(); + now = sched_clock(); + for (i = 0; i < GHES_ESTATUS_CACHES_SIZE; i++) { + cache = rcu_dereference(ghes_estatus_caches[i]); + if (cache == NULL) { + slot = i; + slot_cache = NULL; + break; + } + duration = now - cache->time_in; + if (duration >= GHES_ESTATUS_IN_CACHE_MAX_NSEC) { + slot = i; + slot_cache = cache; + break; + } + count = atomic_read(&cache->count); + period = duration; + do_div(period, (count + 1)); + if (period > max_period) { + max_period = period; + slot = i; + slot_cache = cache; + } + } + /* new_cache must be put into array after its contents are written */ + smp_wmb(); + if (slot != -1 && cmpxchg(ghes_estatus_caches + slot, + slot_cache, new_cache) == slot_cache) { + if (slot_cache) + call_rcu(&slot_cache->rcu, ghes_estatus_cache_rcu_free); + } else + ghes_estatus_cache_free(new_cache); + rcu_read_unlock(); } static int ghes_proc(struct ghes *ghes) @@ -387,9 +648,11 @@ static int ghes_proc(struct ghes *ghes) rc = ghes_read_estatus(ghes, 0); if (rc) goto out; - ghes_print_estatus(NULL, ghes); - ghes_do_proc(ghes); - + if (!ghes_estatus_cached(ghes->estatus)) { + if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) + ghes_estatus_cache_add(ghes->generic, ghes->estatus); + } + ghes_do_proc(ghes->estatus); out: ghes_clear_estatus(ghes); return 0; @@ -447,6 +710,45 @@ static int ghes_notify_sci(struct notifier_block *this, return ret; } +static void ghes_proc_in_irq(struct irq_work *irq_work) +{ + struct llist_node *llnode, *next, *tail = NULL; + struct ghes_estatus_node *estatus_node; + struct acpi_hest_generic *generic; + struct acpi_hest_generic_status *estatus; + u32 len, node_len; + + /* + * Because the time order of estatus in list is reversed, + * revert it back to proper order. + */ + llnode = llist_del_all(&ghes_estatus_llist); + while (llnode) { + next = llnode->next; + llnode->next = tail; + tail = llnode; + llnode = next; + } + llnode = tail; + while (llnode) { + next = llnode->next; + estatus_node = llist_entry(llnode, struct ghes_estatus_node, + llnode); + estatus = GHES_ESTATUS_FROM_NODE(estatus_node); + len = apei_estatus_len(estatus); + node_len = GHES_ESTATUS_NODE_LEN(len); + ghes_do_proc(estatus); + if (!ghes_estatus_cached(estatus)) { + generic = estatus_node->generic; + if (ghes_print_estatus(NULL, generic, estatus)) + ghes_estatus_cache_add(generic, estatus); + } + gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, + node_len); + llnode = next; + } +} + static int ghes_notify_nmi(struct notifier_block *this, unsigned long cmd, void *data) { @@ -476,7 +778,8 @@ static int ghes_notify_nmi(struct notifier_block *this, if (sev_global >= GHES_SEV_PANIC) { oops_begin(); - ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global); + __ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global->generic, + ghes_global->estatus); /* reboot to log the error! */ if (panic_timeout == 0) panic_timeout = ghes_panic_timeout; @@ -484,12 +787,34 @@ static int ghes_notify_nmi(struct notifier_block *this, } list_for_each_entry_rcu(ghes, &ghes_nmi, list) { +#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + u32 len, node_len; + struct ghes_estatus_node *estatus_node; + struct acpi_hest_generic_status *estatus; +#endif if (!(ghes->flags & GHES_TO_CLEAR)) continue; - /* Do not print estatus because printk is not NMI safe */ - ghes_do_proc(ghes); +#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + if (ghes_estatus_cached(ghes->estatus)) + goto next; + /* Save estatus for further processing in IRQ context */ + len = apei_estatus_len(ghes->estatus); + node_len = GHES_ESTATUS_NODE_LEN(len); + estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, + node_len); + if (estatus_node) { + estatus_node->generic = ghes->generic; + estatus = GHES_ESTATUS_FROM_NODE(estatus_node); + memcpy(estatus, ghes->estatus, len); + llist_add(&estatus_node->llnode, &ghes_estatus_llist); + } +next: +#endif ghes_clear_estatus(ghes); } +#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + irq_work_queue(&ghes_proc_irq_work); +#endif out: raw_spin_unlock(&ghes_nmi_lock); @@ -504,10 +829,26 @@ static struct notifier_block ghes_notifier_nmi = { .notifier_call = ghes_notify_nmi, }; +static unsigned long ghes_esource_prealloc_size( + const struct acpi_hest_generic *generic) +{ + unsigned long block_length, prealloc_records, prealloc_size; + + block_length = min_t(unsigned long, generic->error_block_length, + GHES_ESTATUS_MAX_SIZE); + prealloc_records = max_t(unsigned long, + generic->records_to_preallocate, 1); + prealloc_size = min_t(unsigned long, block_length * prealloc_records, + GHES_ESOURCE_PREALLOC_MAX_SIZE); + + return prealloc_size; +} + static int __devinit ghes_probe(struct platform_device *ghes_dev) { struct acpi_hest_generic *generic; struct ghes *ghes = NULL; + unsigned long len; int rc = -EINVAL; generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data; @@ -573,6 +914,8 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev) mutex_unlock(&ghes_list_mutex); break; case ACPI_HEST_NOTIFY_NMI: + len = ghes_esource_prealloc_size(generic); + ghes_estatus_pool_expand(len); mutex_lock(&ghes_list_mutex); if (list_empty(&ghes_nmi)) register_die_notifier(&ghes_notifier_nmi); @@ -597,6 +940,7 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev) { struct ghes *ghes; struct acpi_hest_generic *generic; + unsigned long len; ghes = platform_get_drvdata(ghes_dev); generic = ghes->generic; @@ -627,6 +971,8 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev) * freed after NMI handler finishes. */ synchronize_rcu(); + len = ghes_esource_prealloc_size(generic); + ghes_estatus_pool_shrink(len); break; default: BUG(); @@ -662,15 +1008,43 @@ static int __init ghes_init(void) return -EINVAL; } + if (ghes_disable) { + pr_info(GHES_PFX "GHES is not enabled!\n"); + return -EINVAL; + } + + init_irq_work(&ghes_proc_irq_work, ghes_proc_in_irq); + rc = ghes_ioremap_init(); if (rc) goto err; - rc = platform_driver_register(&ghes_platform_driver); + rc = ghes_estatus_pool_init(); if (rc) goto err_ioremap_exit; + rc = ghes_estatus_pool_expand(GHES_ESTATUS_CACHE_AVG_SIZE * + GHES_ESTATUS_CACHE_ALLOCED_MAX); + if (rc) + goto err_pool_exit; + + rc = platform_driver_register(&ghes_platform_driver); + if (rc) + goto err_pool_exit; + + rc = apei_osc_setup(); + if (rc == 0 && osc_sb_apei_support_acked) + pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit and WHEA _OSC.\n"); + else if (rc == 0 && !osc_sb_apei_support_acked) + pr_info(GHES_PFX "APEI firmware first mode is enabled by WHEA _OSC.\n"); + else if (rc && osc_sb_apei_support_acked) + pr_info(GHES_PFX "APEI firmware first mode is enabled by APEI bit.\n"); + else + pr_info(GHES_PFX "Failed to enable APEI firmware first mode.\n"); + return 0; +err_pool_exit: + ghes_estatus_pool_exit(); err_ioremap_exit: ghes_ioremap_exit(); err: @@ -680,6 +1054,7 @@ err: static void __exit ghes_exit(void) { platform_driver_unregister(&ghes_platform_driver); + ghes_estatus_pool_exit(); ghes_ioremap_exit(); } diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c index 181bc2f..05fee06 100644 --- a/drivers/acpi/apei/hest.c +++ b/drivers/acpi/apei/hest.c @@ -231,16 +231,17 @@ void __init acpi_hest_init(void) goto err; } - rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count); - if (rc) - goto err; - - rc = hest_ghes_dev_register(ghes_count); - if (!rc) { - pr_info(HEST_PFX "Table parsing has been initialized.\n"); - return; + if (!ghes_disable) { + rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count); + if (rc) + goto err; + rc = hest_ghes_dev_register(ghes_count); + if (rc) + goto err; } + pr_info(HEST_PFX "Table parsing has been initialized.\n"); + return; err: hest_disable = 1; } diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index d1e06c1..437ddbf 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -39,6 +39,7 @@ #include <linux/pci.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> +#include <acpi/apei.h> #include <linux/dmi.h> #include <linux/suspend.h> @@ -519,6 +520,7 @@ out_kfree: } EXPORT_SYMBOL(acpi_run_osc); +bool osc_sb_apei_support_acked; static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48"; static void acpi_bus_osc_support(void) { @@ -541,11 +543,19 @@ static void acpi_bus_osc_support(void) #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE) capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_PPC_OST_SUPPORT; #endif + + if (!ghes_disable) + capbuf[OSC_SUPPORT_TYPE] |= OSC_SB_APEI_SUPPORT; if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) return; - if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) + if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) { + u32 *capbuf_ret = context.ret.pointer; + if (context.ret.length > OSC_SUPPORT_TYPE) + osc_sb_apei_support_acked = + capbuf_ret[OSC_SUPPORT_TYPE] & OSC_SB_APEI_SUPPORT; kfree(context.ret.pointer); - /* do we need to check the returned cap? Sounds no */ + } + /* do we need to check other returned cap? Sounds no */ } /* -------------------------------------------------------------------------- diff --git a/include/acpi/apei.h b/include/acpi/apei.h index e67b523..51a527d 100644 --- a/include/acpi/apei.h +++ b/include/acpi/apei.h @@ -18,6 +18,11 @@ extern int hest_disable; extern int erst_disable; +#ifdef CONFIG_ACPI_APEI_GHES +extern int ghes_disable; +#else +#define ghes_disable 1 +#endif #ifdef CONFIG_ACPI_APEI void __init acpi_hest_init(void); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 2312e85..6001b4da 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -279,6 +279,8 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context); #define OSC_SB_CPUHP_OST_SUPPORT 8 #define OSC_SB_APEI_SUPPORT 16 +extern bool osc_sb_apei_support_acked; + /* PCI defined _OSC bits */ /* _OSC DW1 Definition (OS Support Fields) */ #define OSC_EXT_PCI_CONFIG_SUPPORT 1 diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 3bac44c..7ad6345 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -146,6 +146,7 @@ extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits); extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits); +#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG)) #define BITMAP_LAST_WORD_MASK(nbits) \ ( \ ((nbits) % BITS_PER_LONG) ? \ diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h index 5bbebda..5e98eeb 100644 --- a/include/linux/genalloc.h +++ b/include/linux/genalloc.h @@ -1,8 +1,26 @@ /* - * Basic general purpose allocator for managing special purpose memory - * not managed by the regular kmalloc/kfree interface. - * Uses for this includes on-device special memory, uncached memory - * etc. + * Basic general purpose allocator for managing special purpose + * memory, for example, memory that is not managed by the regular + * kmalloc/kfree interface. Uses for this includes on-device special + * memory, uncached memory etc. + * + * It is safe to use the allocator in NMI handlers and other special + * unblockable contexts that could otherwise deadlock on locks. This + * is implemented by using atomic operations and retries on any + * conflicts. The disadvantage is that there may be livelocks in + * extreme cases. For better scalability, one allocator can be used + * for each CPU. + * + * The lockless operation only works if there is enough memory + * available. If new memory is added to the pool a lock has to be + * still taken. So any user relying on locklessness has to ensure + * that sufficient memory is preallocated. + * + * The basic atomic operation of this allocator is cmpxchg on long. + * On architectures that don't have NMI-safe cmpxchg implementation, + * the allocator can NOT be used in NMI handler. So code uses the + * allocator in NMI handler should depend on + * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. * * This source code is licensed under the GNU General Public License, * Version 2. See the file COPYING for more details. @@ -15,7 +33,7 @@ * General purpose special memory pool descriptor. */ struct gen_pool { - rwlock_t lock; + spinlock_t lock; struct list_head chunks; /* list of chunks in this pool */ int min_alloc_order; /* minimum allocation order */ }; @@ -24,8 +42,8 @@ struct gen_pool { * General purpose special memory pool chunk descriptor. */ struct gen_pool_chunk { - spinlock_t lock; struct list_head next_chunk; /* next chunk in pool */ + atomic_t avail; phys_addr_t phys_addr; /* physical starting address of memory chunk */ unsigned long start_addr; /* starting address of memory chunk */ unsigned long end_addr; /* ending address of memory chunk */ @@ -56,4 +74,8 @@ static inline int gen_pool_add(struct gen_pool *pool, unsigned long addr, extern void gen_pool_destroy(struct gen_pool *); extern unsigned long gen_pool_alloc(struct gen_pool *, size_t); extern void gen_pool_free(struct gen_pool *, unsigned long, size_t); +extern void gen_pool_for_each_chunk(struct gen_pool *, + void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *); +extern size_t gen_pool_avail(struct gen_pool *); +extern size_t gen_pool_size(struct gen_pool *); #endif /* __GENALLOC_H__ */ diff --git a/include/linux/llist.h b/include/linux/llist.h new file mode 100644 index 0000000..aa0c8b5 --- /dev/null +++ b/include/linux/llist.h @@ -0,0 +1,126 @@ +#ifndef LLIST_H +#define LLIST_H +/* + * Lock-less NULL terminated single linked list + * + * If there are multiple producers and multiple consumers, llist_add + * can be used in producers and llist_del_all can be used in + * consumers. They can work simultaneously without lock. But + * llist_del_first can not be used here. Because llist_del_first + * depends on list->first->next does not changed if list->first is not + * changed during its operation, but llist_del_first, llist_add, + * llist_add (or llist_del_all, llist_add, llist_add) sequence in + * another consumer may violate that. + * + * If there are multiple producers and one consumer, llist_add can be + * used in producers and llist_del_all or llist_del_first can be used + * in the consumer. + * + * This can be summarized as follow: + * + * | add | del_first | del_all + * add | - | - | - + * del_first | | L | L + * del_all | | | - + * + * Where "-" stands for no lock is needed, while "L" stands for lock + * is needed. + * + * The list entries deleted via llist_del_all can be traversed with + * traversing function such as llist_for_each etc. But the list + * entries can not be traversed safely before deleted from the list. + * The order of deleted entries is from the newest to the oldest added + * one. If you want to traverse from the oldest to the newest, you + * must reverse the order by yourself before traversing. + * + * The basic atomic operation of this list is cmpxchg on long. On + * architectures that don't have NMI-safe cmpxchg implementation, the + * list can NOT be used in NMI handler. So code uses the list in NMI + * handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. + */ + +struct llist_head { + struct llist_node *first; +}; + +struct llist_node { + struct llist_node *next; +}; + +#define LLIST_HEAD_INIT(name) { NULL } +#define LLIST_HEAD(name) struct llist_head name = LLIST_HEAD_INIT(name) + +/** + * init_llist_head - initialize lock-less list head + * @head: the head for your lock-less list + */ +static inline void init_llist_head(struct llist_head *list) +{ + list->first = NULL; +} + +/** + * llist_entry - get the struct of this entry + * @ptr: the &struct llist_node pointer. + * @type: the type of the struct this is embedded in. + * @member: the name of the llist_node within the struct. + */ +#define llist_entry(ptr, type, member) \ + container_of(ptr, type, member) + +/** + * llist_for_each - iterate over some deleted entries of a lock-less list + * @pos: the &struct llist_node to use as a loop cursor + * @node: the first entry of deleted list entries + * + * In general, some entries of the lock-less list can be traversed + * safely only after being deleted from list, so start with an entry + * instead of list head. + * + * If being used on entries deleted from lock-less list directly, the + * traverse order is from the newest to the oldest added entry. If + * you want to traverse from the oldest to the newest, you must + * reverse the order by yourself before traversing. + */ +#define llist_for_each(pos, node) \ + for ((pos) = (node); pos; (pos) = (pos)->next) + +/** + * llist_for_each_entry - iterate over some deleted entries of lock-less list of given type + * @pos: the type * to use as a loop cursor. + * @node: the fist entry of deleted list entries. + * @member: the name of the llist_node with the struct. + * + * In general, some entries of the lock-less list can be traversed + * safely only after being removed from list, so start with an entry + * instead of list head. + * + * If being used on entries deleted from lock-less list directly, the + * traverse order is from the newest to the oldest added entry. If + * you want to traverse from the oldest to the newest, you must + * reverse the order by yourself before traversing. + */ +#define llist_for_each_entry(pos, node, member) \ + for ((pos) = llist_entry((node), typeof(*(pos)), member); \ + &(pos)->member != NULL; \ + (pos) = llist_entry((pos)->member.next, typeof(*(pos)), member)) + +/** + * llist_empty - tests whether a lock-less list is empty + * @head: the list to test + * + * Not guaranteed to be accurate or up to date. Just a quick way to + * test whether the list is empty without deleting something from the + * list. + */ +static inline int llist_empty(const struct llist_head *head) +{ + return ACCESS_ONCE(head->first) == NULL; +} + +void llist_add(struct llist_node *new, struct llist_head *head); +void llist_add_batch(struct llist_node *new_first, struct llist_node *new_last, + struct llist_head *head); +struct llist_node *llist_del_first(struct llist_head *head); +struct llist_node *llist_del_all(struct llist_head *head); +#endif /* LLIST_H */ diff --git a/include/linux/mm.h b/include/linux/mm.h index 3172a1c..f2690cf 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1600,6 +1600,7 @@ enum mf_flags { }; extern void memory_failure(unsigned long pfn, int trapno); extern int __memory_failure(unsigned long pfn, int trapno, int flags); +extern void memory_failure_queue(unsigned long pfn, int trapno, int flags); extern int unpoison_memory(unsigned long pfn); extern int sysctl_memory_failure_early_kill; extern int sysctl_memory_failure_recovery; diff --git a/lib/Kconfig b/lib/Kconfig index 32f3e5a..6c695ff 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -276,4 +276,7 @@ config CORDIC so its calculations are in fixed point. Modules can select this when they require this function. Module will be called cordic. +config LLIST + bool + endmenu diff --git a/lib/Makefile b/lib/Makefile index 892f4e2..6457af4a 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -115,6 +115,8 @@ obj-$(CONFIG_CPU_RMAP) += cpu_rmap.o obj-$(CONFIG_CORDIC) += cordic.o +obj-$(CONFIG_LLIST) += llist.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/bitmap.c b/lib/bitmap.c index 37ef4b0..2f4412e 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -271,8 +271,6 @@ int __bitmap_weight(const unsigned long *bitmap, int bits) } EXPORT_SYMBOL(__bitmap_weight); -#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG)) - void bitmap_set(unsigned long *map, int start, int nr) { unsigned long *p = map + BIT_WORD(start); diff --git a/lib/genalloc.c b/lib/genalloc.c index 577ddf8..f352cc4 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -1,8 +1,26 @@ /* - * Basic general purpose allocator for managing special purpose memory - * not managed by the regular kmalloc/kfree interface. - * Uses for this includes on-device special memory, uncached memory - * etc. + * Basic general purpose allocator for managing special purpose + * memory, for example, memory that is not managed by the regular + * kmalloc/kfree interface. Uses for this includes on-device special + * memory, uncached memory etc. + * + * It is safe to use the allocator in NMI handlers and other special + * unblockable contexts that could otherwise deadlock on locks. This + * is implemented by using atomic operations and retries on any + * conflicts. The disadvantage is that there may be livelocks in + * extreme cases. For better scalability, one allocator can be used + * for each CPU. + * + * The lockless operation only works if there is enough memory + * available. If new memory is added to the pool a lock has to be + * still taken. So any user relying on locklessness has to ensure + * that sufficient memory is preallocated. + * + * The basic atomic operation of this allocator is cmpxchg on long. + * On architectures that don't have NMI-safe cmpxchg implementation, + * the allocator can NOT be used in NMI handler. So code uses the + * allocator in NMI handler should depend on + * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. * * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org> * @@ -13,8 +31,109 @@ #include <linux/slab.h> #include <linux/module.h> #include <linux/bitmap.h> +#include <linux/rculist.h> +#include <linux/interrupt.h> #include <linux/genalloc.h> +static int set_bits_ll(unsigned long *addr, unsigned long mask_to_set) +{ + unsigned long val, nval; + + nval = *addr; + do { + val = nval; + if (val & mask_to_set) + return -EBUSY; + cpu_relax(); + } while ((nval = cmpxchg(addr, val, val | mask_to_set)) != val); + + return 0; +} + +static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear) +{ + unsigned long val, nval; + + nval = *addr; + do { + val = nval; + if ((val & mask_to_clear) != mask_to_clear) + return -EBUSY; + cpu_relax(); + } while ((nval = cmpxchg(addr, val, val & ~mask_to_clear)) != val); + + return 0; +} + +/* + * bitmap_set_ll - set the specified number of bits at the specified position + * @map: pointer to a bitmap + * @start: a bit position in @map + * @nr: number of bits to set + * + * Set @nr bits start from @start in @map lock-lessly. Several users + * can set/clear the same bitmap simultaneously without lock. If two + * users set the same bit, one user will return remain bits, otherwise + * return 0. + */ +static int bitmap_set_ll(unsigned long *map, int start, int nr) +{ + unsigned long *p = map + BIT_WORD(start); + const int size = start + nr; + int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); + + while (nr - bits_to_set >= 0) { + if (set_bits_ll(p, mask_to_set)) + return nr; + nr -= bits_to_set; + bits_to_set = BITS_PER_LONG; + mask_to_set = ~0UL; + p++; + } + if (nr) { + mask_to_set &= BITMAP_LAST_WORD_MASK(size); + if (set_bits_ll(p, mask_to_set)) + return nr; + } + + return 0; +} + +/* + * bitmap_clear_ll - clear the specified number of bits at the specified position + * @map: pointer to a bitmap + * @start: a bit position in @map + * @nr: number of bits to set + * + * Clear @nr bits start from @start in @map lock-lessly. Several users + * can set/clear the same bitmap simultaneously without lock. If two + * users clear the same bit, one user will return remain bits, + * otherwise return 0. + */ +static int bitmap_clear_ll(unsigned long *map, int start, int nr) +{ + unsigned long *p = map + BIT_WORD(start); + const int size = start + nr; + int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); + unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); + + while (nr - bits_to_clear >= 0) { + if (clear_bits_ll(p, mask_to_clear)) + return nr; + nr -= bits_to_clear; + bits_to_clear = BITS_PER_LONG; + mask_to_clear = ~0UL; + p++; + } + if (nr) { + mask_to_clear &= BITMAP_LAST_WORD_MASK(size); + if (clear_bits_ll(p, mask_to_clear)) + return nr; + } + + return 0; +} /** * gen_pool_create - create a new special memory pool @@ -30,7 +149,7 @@ struct gen_pool *gen_pool_create(int min_alloc_order, int nid) pool = kmalloc_node(sizeof(struct gen_pool), GFP_KERNEL, nid); if (pool != NULL) { - rwlock_init(&pool->lock); + spin_lock_init(&pool->lock); INIT_LIST_HEAD(&pool->chunks); pool->min_alloc_order = min_alloc_order; } @@ -63,14 +182,14 @@ int gen_pool_add_virt(struct gen_pool *pool, unsigned long virt, phys_addr_t phy if (unlikely(chunk == NULL)) return -ENOMEM; - spin_lock_init(&chunk->lock); chunk->phys_addr = phys; chunk->start_addr = virt; chunk->end_addr = virt + size; + atomic_set(&chunk->avail, size); - write_lock(&pool->lock); - list_add(&chunk->next_chunk, &pool->chunks); - write_unlock(&pool->lock); + spin_lock(&pool->lock); + list_add_rcu(&chunk->next_chunk, &pool->chunks); + spin_unlock(&pool->lock); return 0; } @@ -85,19 +204,19 @@ EXPORT_SYMBOL(gen_pool_add_virt); */ phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long addr) { - struct list_head *_chunk; struct gen_pool_chunk *chunk; + phys_addr_t paddr = -1; - read_lock(&pool->lock); - list_for_each(_chunk, &pool->chunks) { - chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); - - if (addr >= chunk->start_addr && addr < chunk->end_addr) - return chunk->phys_addr + addr - chunk->start_addr; + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { + if (addr >= chunk->start_addr && addr < chunk->end_addr) { + paddr = chunk->phys_addr + (addr - chunk->start_addr); + break; + } } - read_unlock(&pool->lock); + rcu_read_unlock(); - return -1; + return paddr; } EXPORT_SYMBOL(gen_pool_virt_to_phys); @@ -115,7 +234,6 @@ void gen_pool_destroy(struct gen_pool *pool) int order = pool->min_alloc_order; int bit, end_bit; - list_for_each_safe(_chunk, _next_chunk, &pool->chunks) { chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); list_del(&chunk->next_chunk); @@ -137,44 +255,50 @@ EXPORT_SYMBOL(gen_pool_destroy); * @size: number of bytes to allocate from the pool * * Allocate the requested number of bytes from the specified pool. - * Uses a first-fit algorithm. + * Uses a first-fit algorithm. Can not be used in NMI handler on + * architectures without NMI-safe cmpxchg implementation. */ unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size) { - struct list_head *_chunk; struct gen_pool_chunk *chunk; - unsigned long addr, flags; + unsigned long addr = 0; int order = pool->min_alloc_order; - int nbits, start_bit, end_bit; + int nbits, start_bit = 0, end_bit, remain; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif if (size == 0) return 0; nbits = (size + (1UL << order) - 1) >> order; - - read_lock(&pool->lock); - list_for_each(_chunk, &pool->chunks) { - chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { + if (size > atomic_read(&chunk->avail)) + continue; end_bit = (chunk->end_addr - chunk->start_addr) >> order; - - spin_lock_irqsave(&chunk->lock, flags); - start_bit = bitmap_find_next_zero_area(chunk->bits, end_bit, 0, - nbits, 0); - if (start_bit >= end_bit) { - spin_unlock_irqrestore(&chunk->lock, flags); +retry: + start_bit = bitmap_find_next_zero_area(chunk->bits, end_bit, + start_bit, nbits, 0); + if (start_bit >= end_bit) continue; + remain = bitmap_set_ll(chunk->bits, start_bit, nbits); + if (remain) { + remain = bitmap_clear_ll(chunk->bits, start_bit, + nbits - remain); + BUG_ON(remain); + goto retry; } addr = chunk->start_addr + ((unsigned long)start_bit << order); - - bitmap_set(chunk->bits, start_bit, nbits); - spin_unlock_irqrestore(&chunk->lock, flags); - read_unlock(&pool->lock); - return addr; + size = nbits << order; + atomic_sub(size, &chunk->avail); + break; } - read_unlock(&pool->lock); - return 0; + rcu_read_unlock(); + return addr; } EXPORT_SYMBOL(gen_pool_alloc); @@ -184,33 +308,95 @@ EXPORT_SYMBOL(gen_pool_alloc); * @addr: starting address of memory to free back to pool * @size: size in bytes of memory to free * - * Free previously allocated special memory back to the specified pool. + * Free previously allocated special memory back to the specified + * pool. Can not be used in NMI handler on architectures without + * NMI-safe cmpxchg implementation. */ void gen_pool_free(struct gen_pool *pool, unsigned long addr, size_t size) { - struct list_head *_chunk; struct gen_pool_chunk *chunk; - unsigned long flags; int order = pool->min_alloc_order; - int bit, nbits; + int start_bit, nbits, remain; - nbits = (size + (1UL << order) - 1) >> order; - - read_lock(&pool->lock); - list_for_each(_chunk, &pool->chunks) { - chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk); +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + nbits = (size + (1UL << order) - 1) >> order; + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { if (addr >= chunk->start_addr && addr < chunk->end_addr) { BUG_ON(addr + size > chunk->end_addr); - spin_lock_irqsave(&chunk->lock, flags); - bit = (addr - chunk->start_addr) >> order; - while (nbits--) - __clear_bit(bit++, chunk->bits); - spin_unlock_irqrestore(&chunk->lock, flags); - break; + start_bit = (addr - chunk->start_addr) >> order; + remain = bitmap_clear_ll(chunk->bits, start_bit, nbits); + BUG_ON(remain); + size = nbits << order; + atomic_add(size, &chunk->avail); + rcu_read_unlock(); + return; } } - BUG_ON(nbits > 0); - read_unlock(&pool->lock); + rcu_read_unlock(); + BUG(); } EXPORT_SYMBOL(gen_pool_free); + +/** + * gen_pool_for_each_chunk - call func for every chunk of generic memory pool + * @pool: the generic memory pool + * @func: func to call + * @data: additional data used by @func + * + * Call @func for every chunk of generic memory pool. The @func is + * called with rcu_read_lock held. + */ +void gen_pool_for_each_chunk(struct gen_pool *pool, + void (*func)(struct gen_pool *pool, struct gen_pool_chunk *chunk, void *data), + void *data) +{ + struct gen_pool_chunk *chunk; + + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &(pool)->chunks, next_chunk) + func(pool, chunk, data); + rcu_read_unlock(); +} +EXPORT_SYMBOL(gen_pool_for_each_chunk); + +/** + * gen_pool_avail - get available free space of the pool + * @pool: pool to get available free space + * + * Return available free space of the specified pool. + */ +size_t gen_pool_avail(struct gen_pool *pool) +{ + struct gen_pool_chunk *chunk; + size_t avail = 0; + + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) + avail += atomic_read(&chunk->avail); + rcu_read_unlock(); + return avail; +} +EXPORT_SYMBOL_GPL(gen_pool_avail); + +/** + * gen_pool_size - get size in bytes of memory managed by the pool + * @pool: pool to get size + * + * Return size in bytes of memory managed by the pool. + */ +size_t gen_pool_size(struct gen_pool *pool) +{ + struct gen_pool_chunk *chunk; + size_t size = 0; + + rcu_read_lock(); + list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) + size += chunk->end_addr - chunk->start_addr; + rcu_read_unlock(); + return size; +} +EXPORT_SYMBOL_GPL(gen_pool_size); diff --git a/lib/llist.c b/lib/llist.c new file mode 100644 index 0000000..da44572 --- /dev/null +++ b/lib/llist.c @@ -0,0 +1,129 @@ +/* + * Lock-less NULL terminated single linked list + * + * The basic atomic operation of this list is cmpxchg on long. On + * architectures that don't have NMI-safe cmpxchg implementation, the + * list can NOT be used in NMI handler. So code uses the list in NMI + * handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. + * + * Copyright 2010,2011 Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation; + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/llist.h> + +#include <asm/system.h> + +/** + * llist_add - add a new entry + * @new: new entry to be added + * @head: the head for your lock-less list + */ +void llist_add(struct llist_node *new, struct llist_head *head) +{ + struct llist_node *entry, *old_entry; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + old_entry = entry; + new->next = entry; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, new)) != old_entry); +} +EXPORT_SYMBOL_GPL(llist_add); + +/** + * llist_add_batch - add several linked entries in batch + * @new_first: first entry in batch to be added + * @new_last: last entry in batch to be added + * @head: the head for your lock-less list + */ +void llist_add_batch(struct llist_node *new_first, struct llist_node *new_last, + struct llist_head *head) +{ + struct llist_node *entry, *old_entry; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + old_entry = entry; + new_last->next = entry; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, new_first)) != old_entry); +} +EXPORT_SYMBOL_GPL(llist_add_batch); + +/** + * llist_del_first - delete the first entry of lock-less list + * @head: the head for your lock-less list + * + * If list is empty, return NULL, otherwise, return the first entry + * deleted, this is the newest added one. + * + * Only one llist_del_first user can be used simultaneously with + * multiple llist_add users without lock. Because otherwise + * llist_del_first, llist_add, llist_add (or llist_del_all, llist_add, + * llist_add) sequence in another user may change @head->first->next, + * but keep @head->first. If multiple consumers are needed, please + * use llist_del_all or use lock between consumers. + */ +struct llist_node *llist_del_first(struct llist_head *head) +{ + struct llist_node *entry, *old_entry, *next; + +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + entry = head->first; + do { + if (entry == NULL) + return NULL; + old_entry = entry; + next = entry->next; + cpu_relax(); + } while ((entry = cmpxchg(&head->first, old_entry, next)) != old_entry); + + return entry; +} +EXPORT_SYMBOL_GPL(llist_del_first); + +/** + * llist_del_all - delete all entries from lock-less list + * @head: the head of lock-less list to delete all entries + * + * If list is empty, return NULL, otherwise, delete all entries and + * return the pointer to the first entry. The order of entries + * deleted is from the newest to the oldest added one. + */ +struct llist_node *llist_del_all(struct llist_head *head) +{ +#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG + BUG_ON(in_nmi()); +#endif + + return xchg(&head->first, NULL); +} +EXPORT_SYMBOL_GPL(llist_del_all); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 740c4f5..2b43ba0 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -53,6 +53,7 @@ #include <linux/hugetlb.h> #include <linux/memory_hotplug.h> #include <linux/mm_inline.h> +#include <linux/kfifo.h> #include "internal.h" int sysctl_memory_failure_early_kill __read_mostly = 0; @@ -1178,6 +1179,97 @@ void memory_failure(unsigned long pfn, int trapno) __memory_failure(pfn, trapno, 0); } +#define MEMORY_FAILURE_FIFO_ORDER 4 +#define MEMORY_FAILURE_FIFO_SIZE (1 << MEMORY_FAILURE_FIFO_ORDER) + +struct memory_failure_entry { + unsigned long pfn; + int trapno; + int flags; +}; + +struct memory_failure_cpu { + DECLARE_KFIFO(fifo, struct memory_failure_entry, + MEMORY_FAILURE_FIFO_SIZE); + spinlock_t lock; + struct work_struct work; +}; + +static DEFINE_PER_CPU(struct memory_failure_cpu, memory_failure_cpu); + +/** + * memory_failure_queue - Schedule handling memory failure of a page. + * @pfn: Page Number of the corrupted page + * @trapno: Trap number reported in the signal to user space. + * @flags: Flags for memory failure handling + * + * This function is called by the low level hardware error handler + * when it detects hardware memory corruption of a page. It schedules + * the recovering of error page, including dropping pages, killing + * processes etc. + * + * The function is primarily of use for corruptions that + * happen outside the current execution context (e.g. when + * detected by a background scrubber) + * + * Can run in IRQ context. + */ +void memory_failure_queue(unsigned long pfn, int trapno, int flags) +{ + struct memory_failure_cpu *mf_cpu; + unsigned long proc_flags; + struct memory_failure_entry entry = { + .pfn = pfn, + .trapno = trapno, + .flags = flags, + }; + + mf_cpu = &get_cpu_var(memory_failure_cpu); + spin_lock_irqsave(&mf_cpu->lock, proc_flags); + if (kfifo_put(&mf_cpu->fifo, &entry)) + schedule_work_on(smp_processor_id(), &mf_cpu->work); + else + pr_err("Memory failure: buffer overflow when queuing memory failure at 0x%#lx\n", + pfn); + spin_unlock_irqrestore(&mf_cpu->lock, proc_flags); + put_cpu_var(memory_failure_cpu); +} +EXPORT_SYMBOL_GPL(memory_failure_queue); + +static void memory_failure_work_func(struct work_struct *work) +{ + struct memory_failure_cpu *mf_cpu; + struct memory_failure_entry entry = { 0, }; + unsigned long proc_flags; + int gotten; + + mf_cpu = &__get_cpu_var(memory_failure_cpu); + for (;;) { + spin_lock_irqsave(&mf_cpu->lock, proc_flags); + gotten = kfifo_get(&mf_cpu->fifo, &entry); + spin_unlock_irqrestore(&mf_cpu->lock, proc_flags); + if (!gotten) + break; + __memory_failure(entry.pfn, entry.trapno, entry.flags); + } +} + +static int __init memory_failure_init(void) +{ + struct memory_failure_cpu *mf_cpu; + int cpu; + + for_each_possible_cpu(cpu) { + mf_cpu = &per_cpu(memory_failure_cpu, cpu); + spin_lock_init(&mf_cpu->lock); + INIT_KFIFO(mf_cpu->fifo); + INIT_WORK(&mf_cpu->work, memory_failure_work_func); + } + + return 0; +} +core_initcall(memory_failure_init); + /** * unpoison_memory - Unpoison a previously poisoned page * @pfn: Page number of the to be unpoisoned page |