From c35f77417ebfc7c21c02aa9c8c30aa4cecf331d6 Mon Sep 17 00:00:00 2001 From: Ido Yariv Date: Mon, 11 Jun 2012 12:56:45 +0300 Subject: x86: Define early read-mostly per-cpu macros Some read-mostly per-cpu data may need to be declared or defined early, so it can be initialized and accessed before per_cpu areas are allocated. Only the data that resides in the per_cpu areas should be read-mostly, as there is little benefit in optimizing cache lines on initialization. Signed-off-by: Ido Yariv [ Added the missing declarations in !SMP code. ] Signed-off-by: Vlad Zolotarov Acked-by: Shai Fultheim Cc: Linus Torvalds Cc: Andrew Morton Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/46188571.ddB8aVQYWo@vlad Signed-off-by: Ingo Molnar --- arch/x86/include/asm/percpu.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h index d9b8e3f7f42a..1104afaba52b 100644 --- a/arch/x86/include/asm/percpu.h +++ b/arch/x86/include/asm/percpu.h @@ -551,6 +551,12 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off); { [0 ... NR_CPUS-1] = _initvalue }; \ __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map +#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \ + DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue; \ + __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \ + { [0 ... NR_CPUS-1] = _initvalue }; \ + __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map + #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ EXPORT_PER_CPU_SYMBOL(_name) @@ -559,6 +565,11 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off); extern __typeof__(_type) *_name##_early_ptr; \ extern __typeof__(_type) _name##_early_map[] +#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \ + DECLARE_PER_CPU_READ_MOSTLY(_type, _name); \ + extern __typeof__(_type) *_name##_early_ptr; \ + extern __typeof__(_type) _name##_early_map[] + #define early_per_cpu_ptr(_name) (_name##_early_ptr) #define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx]) #define early_per_cpu(_name, _cpu) \ @@ -570,12 +581,18 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off); #define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \ DEFINE_PER_CPU(_type, _name) = _initvalue +#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \ + DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue + #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ EXPORT_PER_CPU_SYMBOL(_name) #define DECLARE_EARLY_PER_CPU(_type, _name) \ DECLARE_PER_CPU(_type, _name) +#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \ + DECLARE_PER_CPU_READ_MOSTLY(_type, _name) + #define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu) #define early_per_cpu_ptr(_name) NULL /* no early_per_cpu_map() */ -- cgit v1.2.1 From 0816b0f0365539c8f6280634d2c1778d0108d8f5 Mon Sep 17 00:00:00 2001 From: Vlad Zolotarov Date: Mon, 11 Jun 2012 12:56:52 +0300 Subject: x86: Add read_mostly declaration/definition to variables from smp.h Add "read-mostly" qualifier to the following variables in smp.h: - cpu_sibling_map - cpu_core_map - cpu_llc_shared_map - cpu_llc_id - cpu_number - x86_cpu_to_apicid - x86_bios_cpu_apicid - x86_cpu_to_logical_apicid As long as all the variables above are only written during the initialization, this change is meant to prevent the false sharing. More specifically, on vSMP Foundation platform x86_cpu_to_apicid shared the same internode_cache_line with frequently written lapic_events. From the analysis of the first 33 per_cpu variables out of 219 (memories they describe, to be more specific) the 8 have read_mostly nature (tlb_vector_offset, cpu_loops_per_jiffy, xen_debug_irq, etc.) and 25 are frequently written (irq_stack_union, gdt_page, exception_stacks, idt_desc, etc.). Assuming that the spread of the rest of the per_cpu variables is similar, identifying the read mostly memories will make more sense in terms of long-term code maintenance comparing to identifying frequently written memories. Signed-off-by: Vlad Zolotarov Acked-by: Shai Fultheim Cc: Shai Fultheim (Shai@ScaleMP.com) Cc: ido@wizery.com Cc: Linus Torvalds Cc: Andrew Morton Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1719258.EYKzE4Zbq5@vlad Signed-off-by: Ingo Molnar --- arch/x86/include/asm/apic.h | 2 +- arch/x86/include/asm/smp.h | 16 ++++++++-------- arch/x86/kernel/apic/apic.c | 6 +++--- arch/x86/kernel/setup_percpu.c | 2 +- arch/x86/kernel/smpboot.c | 8 ++++---- 5 files changed, 17 insertions(+), 17 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index eaff4790ed96..a907d4d251a8 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -537,7 +537,7 @@ static inline const struct cpumask *default_target_cpus(void) #endif } -DECLARE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid); +DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid); static inline unsigned int read_apic_id(void) diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index f48394513c37..cc1df2b5cc65 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -31,12 +31,12 @@ static inline bool cpu_has_ht_siblings(void) return has_siblings; } -DECLARE_PER_CPU(cpumask_var_t, cpu_sibling_map); -DECLARE_PER_CPU(cpumask_var_t, cpu_core_map); +DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); +DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map); /* cpus sharing the last level cache: */ -DECLARE_PER_CPU(cpumask_var_t, cpu_llc_shared_map); -DECLARE_PER_CPU(u16, cpu_llc_id); -DECLARE_PER_CPU(int, cpu_number); +DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); +DECLARE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id); +DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number); static inline struct cpumask *cpu_sibling_mask(int cpu) { @@ -53,10 +53,10 @@ static inline struct cpumask *cpu_llc_shared_mask(int cpu) return per_cpu(cpu_llc_shared_map, cpu); } -DECLARE_EARLY_PER_CPU(u16, x86_cpu_to_apicid); -DECLARE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid); +DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid); +DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid); #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32) -DECLARE_EARLY_PER_CPU(int, x86_cpu_to_logical_apicid); +DECLARE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid); #endif /* Static state in head.S used to set up a CPU */ diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 39a222e094af..0443b6482214 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -75,8 +75,8 @@ physid_mask_t phys_cpu_present_map; /* * Map cpu index to physical APIC ID */ -DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID); -DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID); +DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID); +DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID); EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid); EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid); @@ -88,7 +88,7 @@ EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid); * used for the mapping. This is where the behaviors of x86_64 and 32 * actually diverge. Let's keep it ugly for now. */ -DEFINE_EARLY_PER_CPU(int, x86_cpu_to_logical_apicid, BAD_APICID); +DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID); /* * Knob to control our willingness to enable the local APIC. diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 5a98aa272184..5cdff0357746 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -21,7 +21,7 @@ #include #include -DEFINE_PER_CPU(int, cpu_number); +DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number); EXPORT_PER_CPU_SYMBOL(cpu_number); #ifdef CONFIG_X86_64 diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 3fab55bea29b..e61110e29a8c 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -104,17 +104,17 @@ int smp_num_siblings = 1; EXPORT_SYMBOL(smp_num_siblings); /* Last level cache ID of each logical CPU */ -DEFINE_PER_CPU(u16, cpu_llc_id) = BAD_APICID; +DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID; /* representing HT siblings of each logical CPU */ -DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map); +DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); EXPORT_PER_CPU_SYMBOL(cpu_sibling_map); /* representing HT and core siblings of each logical CPU */ -DEFINE_PER_CPU(cpumask_var_t, cpu_core_map); +DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map); EXPORT_PER_CPU_SYMBOL(cpu_core_map); -DEFINE_PER_CPU(cpumask_var_t, cpu_llc_shared_map); +DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); /* Per CPU bogomips and other parameters */ DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info); -- cgit v1.2.1 From e0ba94f14f747c2661c4d21f8c44e5b0b8cd8e48 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:16 +0800 Subject: x86/tlb_info: get last level TLB entry number of CPU For 4KB pages, x86 CPU has 2 or 1 level TLB, first level is data TLB and instruction TLB, second level is shared TLB for both data and instructions. For hupe page TLB, usually there is just one level and seperated by 2MB/4MB and 1GB. Although each levels TLB size is important for performance tuning, but for genernal and rude optimizing, last level TLB entry number is suitable. And in fact, last level TLB always has the biggest entry number. This patch will get the biggest TLB entry number and use it in furture TLB optimizing. Accroding Borislav's suggestion, except tlb_ll[i/d]_* array, other function and data will be released after system boot up. For all kinds of x86 vendor friendly, vendor specific code was moved to its specific files. Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-2-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/processor.h | 11 +++ arch/x86/kernel/cpu/common.c | 21 ++++++ arch/x86/kernel/cpu/cpu.h | 9 +++ arch/x86/kernel/cpu/intel.c | 142 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 183 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 39bc5777211a..39b2bd48dfbc 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -61,6 +61,17 @@ static inline void *current_text_addr(void) # define ARCH_MIN_MMSTRUCT_ALIGN 0 #endif +enum tlb_infos { + ENTRIES, + NR_INFO +}; + +extern u16 __read_mostly tlb_lli_4k[NR_INFO]; +extern u16 __read_mostly tlb_lli_2m[NR_INFO]; +extern u16 __read_mostly tlb_lli_4m[NR_INFO]; +extern u16 __read_mostly tlb_lld_4k[NR_INFO]; +extern u16 __read_mostly tlb_lld_2m[NR_INFO]; +extern u16 __read_mostly tlb_lld_4m[NR_INFO]; /* * CPU type and hardware bug flags. Kept separately for each CPU. * Members of this structure are referenced in head.S, so think twice diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 6b9333b429ba..b2016df00813 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -452,6 +452,25 @@ void __cpuinit cpu_detect_cache_sizes(struct cpuinfo_x86 *c) c->x86_cache_size = l2size; } +u16 __read_mostly tlb_lli_4k[NR_INFO]; +u16 __read_mostly tlb_lli_2m[NR_INFO]; +u16 __read_mostly tlb_lli_4m[NR_INFO]; +u16 __read_mostly tlb_lld_4k[NR_INFO]; +u16 __read_mostly tlb_lld_2m[NR_INFO]; +u16 __read_mostly tlb_lld_4m[NR_INFO]; + +void __cpuinit cpu_detect_tlb(struct cpuinfo_x86 *c) +{ + if (this_cpu->c_detect_tlb) + this_cpu->c_detect_tlb(c); + + printk(KERN_INFO "Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \ + "Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d\n", + tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES], + tlb_lli_4m[ENTRIES], tlb_lld_4k[ENTRIES], + tlb_lld_2m[ENTRIES], tlb_lld_4m[ENTRIES]); +} + void __cpuinit detect_ht(struct cpuinfo_x86 *c) { #ifdef CONFIG_X86_HT @@ -911,6 +930,8 @@ void __init identify_boot_cpu(void) #else vgetcpu_set_mode(); #endif + if (boot_cpu_data.cpuid_level >= 2) + cpu_detect_tlb(&boot_cpu_data); } void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c) diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h index 8bacc7826fb3..4041c24ae7db 100644 --- a/arch/x86/kernel/cpu/cpu.h +++ b/arch/x86/kernel/cpu/cpu.h @@ -20,10 +20,19 @@ struct cpu_dev { void (*c_bsp_init)(struct cpuinfo_x86 *); void (*c_init)(struct cpuinfo_x86 *); void (*c_identify)(struct cpuinfo_x86 *); + void (*c_detect_tlb)(struct cpuinfo_x86 *); unsigned int (*c_size_cache)(struct cpuinfo_x86 *, unsigned int); int c_x86_vendor; }; +struct _tlb_table { + unsigned char descriptor; + char tlb_type; + unsigned int entries; + /* unsigned int ways; */ + char info[128]; +}; + #define cpu_dev_register(cpu_devX) \ static const struct cpu_dev *const __cpu_dev_##cpu_devX __used \ __attribute__((__section__(".x86_cpu_dev.init"))) = \ diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 3e6ff6cbf42a..ed0d512cf51b 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -491,6 +491,147 @@ static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 *c, unsigned i } #endif +#define TLB_INST_4K 0x01 +#define TLB_INST_4M 0x02 +#define TLB_INST_2M_4M 0x03 + +#define TLB_INST_ALL 0x05 +#define TLB_INST_1G 0x06 + +#define TLB_DATA_4K 0x11 +#define TLB_DATA_4M 0x12 +#define TLB_DATA_2M_4M 0x13 +#define TLB_DATA_4K_4M 0x14 + +#define TLB_DATA_1G 0x16 + +#define TLB_DATA0_4K 0x21 +#define TLB_DATA0_4M 0x22 +#define TLB_DATA0_2M_4M 0x23 + +#define STLB_4K 0x41 + +static const struct _tlb_table intel_tlb_table[] __cpuinitconst = { + { 0x01, TLB_INST_4K, 32, " TLB_INST 4 KByte pages, 4-way set associative" }, + { 0x02, TLB_INST_4M, 2, " TLB_INST 4 MByte pages, full associative" }, + { 0x03, TLB_DATA_4K, 64, " TLB_DATA 4 KByte pages, 4-way set associative" }, + { 0x04, TLB_DATA_4M, 8, " TLB_DATA 4 MByte pages, 4-way set associative" }, + { 0x05, TLB_DATA_4M, 32, " TLB_DATA 4 MByte pages, 4-way set associative" }, + { 0x0b, TLB_INST_4M, 4, " TLB_INST 4 MByte pages, 4-way set associative" }, + { 0x4f, TLB_INST_4K, 32, " TLB_INST 4 KByte pages */" }, + { 0x50, TLB_INST_ALL, 64, " TLB_INST 4 KByte and 2-MByte or 4-MByte pages" }, + { 0x51, TLB_INST_ALL, 128, " TLB_INST 4 KByte and 2-MByte or 4-MByte pages" }, + { 0x52, TLB_INST_ALL, 256, " TLB_INST 4 KByte and 2-MByte or 4-MByte pages" }, + { 0x55, TLB_INST_2M_4M, 7, " TLB_INST 2-MByte or 4-MByte pages, fully associative" }, + { 0x56, TLB_DATA0_4M, 16, " TLB_DATA0 4 MByte pages, 4-way set associative" }, + { 0x57, TLB_DATA0_4K, 16, " TLB_DATA0 4 KByte pages, 4-way associative" }, + { 0x59, TLB_DATA0_4K, 16, " TLB_DATA0 4 KByte pages, fully associative" }, + { 0x5a, TLB_DATA0_2M_4M, 32, " TLB_DATA0 2-MByte or 4 MByte pages, 4-way set associative" }, + { 0x5b, TLB_DATA_4K_4M, 64, " TLB_DATA 4 KByte and 4 MByte pages" }, + { 0x5c, TLB_DATA_4K_4M, 128, " TLB_DATA 4 KByte and 4 MByte pages" }, + { 0x5d, TLB_DATA_4K_4M, 256, " TLB_DATA 4 KByte and 4 MByte pages" }, + { 0xb0, TLB_INST_4K, 128, " TLB_INST 4 KByte pages, 4-way set associative" }, + { 0xb1, TLB_INST_2M_4M, 4, " TLB_INST 2M pages, 4-way, 8 entries or 4M pages, 4-way entries" }, + { 0xb2, TLB_INST_4K, 64, " TLB_INST 4KByte pages, 4-way set associative" }, + { 0xb3, TLB_DATA_4K, 128, " TLB_DATA 4 KByte pages, 4-way set associative" }, + { 0xb4, TLB_DATA_4K, 256, " TLB_DATA 4 KByte pages, 4-way associative" }, + { 0xba, TLB_DATA_4K, 64, " TLB_DATA 4 KByte pages, 4-way associative" }, + { 0xc0, TLB_DATA_4K_4M, 8, " TLB_DATA 4 KByte and 4 MByte pages, 4-way associative" }, + { 0xca, STLB_4K, 512, " STLB 4 KByte pages, 4-way associative" }, + { 0x00, 0, 0 } +}; + +static void __cpuinit intel_tlb_lookup(const unsigned char desc) +{ + unsigned char k; + if (desc == 0) + return; + + /* look up this descriptor in the table */ + for (k = 0; intel_tlb_table[k].descriptor != desc && \ + intel_tlb_table[k].descriptor != 0; k++) + ; + + if (intel_tlb_table[k].tlb_type == 0) + return; + + switch (intel_tlb_table[k].tlb_type) { + case STLB_4K: + if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_INST_ALL: + if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_INST_4K: + if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_INST_4M: + if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_INST_2M_4M: + if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_DATA_4K: + case TLB_DATA0_4K: + if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_DATA_4M: + case TLB_DATA0_4M: + if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_DATA_2M_4M: + case TLB_DATA0_2M_4M: + if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + case TLB_DATA_4K_4M: + if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries; + if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries) + tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries; + break; + } +} + +static void __cpuinit intel_detect_tlb(struct cpuinfo_x86 *c) +{ + int i, j, n; + unsigned int regs[4]; + unsigned char *desc = (unsigned char *)regs; + /* Number of times to iterate */ + n = cpuid_eax(2) & 0xFF; + + for (i = 0 ; i < n ; i++) { + cpuid(2, ®s[0], ®s[1], ®s[2], ®s[3]); + + /* If bit 31 is set, this is an unknown format */ + for (j = 0 ; j < 3 ; j++) + if (regs[j] & (1 << 31)) + regs[j] = 0; + + /* Byte 0 is level count, not a descriptor */ + for (j = 1 ; j < 16 ; j++) + intel_tlb_lookup(desc[j]); + } +} + static const struct cpu_dev __cpuinitconst intel_cpu_dev = { .c_vendor = "Intel", .c_ident = { "GenuineIntel" }, @@ -546,6 +687,7 @@ static const struct cpu_dev __cpuinitconst intel_cpu_dev = { }, .c_size_cache = intel_size_cache, #endif + .c_detect_tlb = intel_detect_tlb, .c_early_init = early_init_intel, .c_init = init_intel, .c_x86_vendor = X86_VENDOR_INTEL, -- cgit v1.2.1 From e7b52ffd45a6d834473f43b349e7d86593d763c7 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:17 +0800 Subject: x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range x86 has no flush_tlb_range support in instruction level. Currently the flush_tlb_range just implemented by flushing all page table. That is not the best solution for all scenarios. In fact, if we just use 'invlpg' to flush few lines from TLB, we can get the performance gain from later remain TLB lines accessing. But the 'invlpg' instruction costs much of time. Its execution time can compete with cr3 rewriting, and even a bit more on SNB CPU. So, on a 512 4KB TLB entries CPU, the balance points is at: (512 - X) * 100ns(assumed TLB refill cost) = X(TLB flush entries) * 100ns(assumed invlpg cost) Here, X is 256, that is 1/2 of 512 entries. But with the mysterious CPU pre-fetcher and page miss handler Unit, the assumed TLB refill cost is far lower then 100ns in sequential access. And 2 HT siblings in one core makes the memory access more faster if they are accessing the same memory. So, in the patch, I just do the change when the target entries is less than 1/16 of whole active tlb entries. Actually, I have no data support for the percentage '1/16', so any suggestions are welcomed. As to hugetlb, guess due to smaller page table, and smaller active TLB entries, I didn't see benefit via my benchmark, so no optimizing now. My micro benchmark show in ideal scenarios, the performance improves 70 percent in reading. And in worst scenario, the reading/writing performance is similar with unpatched 3.4-rc4 kernel. Here is the reading data on my 2P * 4cores *HT NHM EP machine, with THP 'always': multi thread testing, '-t' paramter is thread number: with patch unpatched 3.4-rc4 ./mprotect -t 1 14ns 24ns ./mprotect -t 2 13ns 22ns ./mprotect -t 4 12ns 19ns ./mprotect -t 8 14ns 16ns ./mprotect -t 16 28ns 26ns ./mprotect -t 32 54ns 51ns ./mprotect -t 128 200ns 199ns Single process with sequencial flushing and memory accessing: with patch unpatched 3.4-rc4 ./mprotect 7ns 11ns ./mprotect -p 4096 -l 8 -n 10240 21ns 21ns [ hpa: http://lkml.kernel.org/r/1B4B44D9196EFF41AE41FDA404FC0A100BFF94@SHSMSX101.ccr.corp.intel.com has additional performance numbers. ] Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-3-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/paravirt.h | 5 +- arch/x86/include/asm/paravirt_types.h | 3 +- arch/x86/include/asm/tlbflush.h | 23 ++++----- arch/x86/include/asm/uv/uv.h | 5 +- arch/x86/mm/tlb.c | 97 +++++++++++++++++++++++++++++------ arch/x86/platform/uv/tlb_uv.c | 6 +-- arch/x86/xen/mmu.c | 12 ++--- 7 files changed, 107 insertions(+), 44 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 6cbbabf52707..7e2c2a635737 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -397,9 +397,10 @@ static inline void __flush_tlb_single(unsigned long addr) static inline void flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, - unsigned long va) + unsigned long start, + unsigned long end) { - PVOP_VCALL3(pv_mmu_ops.flush_tlb_others, cpumask, mm, va); + PVOP_VCALL4(pv_mmu_ops.flush_tlb_others, cpumask, mm, start, end); } static inline int paravirt_pgd_alloc(struct mm_struct *mm) diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 8e8b9a4987ee..600a5fcac9cd 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -250,7 +250,8 @@ struct pv_mmu_ops { void (*flush_tlb_single)(unsigned long addr); void (*flush_tlb_others)(const struct cpumask *cpus, struct mm_struct *mm, - unsigned long va); + unsigned long start, + unsigned long end); /* Hooks for allocating and freeing a pagetable top-level */ int (*pgd_alloc)(struct mm_struct *mm); diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 36a1a2ab87d2..33608d96d68b 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -73,14 +73,10 @@ static inline void __flush_tlb_one(unsigned long addr) * - flush_tlb_page(vma, vmaddr) flushes one page * - flush_tlb_range(vma, start, end) flushes a range of pages * - flush_tlb_kernel_range(start, end) flushes a range of kernel pages - * - flush_tlb_others(cpumask, mm, va) flushes TLBs on other cpus + * - flush_tlb_others(cpumask, mm, start, end) flushes TLBs on other cpus * * ..but the i386 has somewhat limited tlb flushing capabilities, * and page-granular flushes are available only on i486 and up. - * - * x86-64 can only flush individual pages or full VMs. For a range flush - * we always do the full VM. Might be worth trying if for a small - * range a few INVLPGs in a row are a win. */ #ifndef CONFIG_SMP @@ -111,7 +107,8 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, static inline void native_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, - unsigned long va) + unsigned long start, + unsigned long end) { } @@ -129,17 +126,14 @@ extern void flush_tlb_all(void); extern void flush_tlb_current_task(void); extern void flush_tlb_mm(struct mm_struct *); extern void flush_tlb_page(struct vm_area_struct *, unsigned long); +extern void flush_tlb_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end); #define flush_tlb() flush_tlb_current_task() -static inline void flush_tlb_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end) -{ - flush_tlb_mm(vma->vm_mm); -} - void native_flush_tlb_others(const struct cpumask *cpumask, - struct mm_struct *mm, unsigned long va); + struct mm_struct *mm, + unsigned long start, unsigned long end); #define TLBSTATE_OK 1 #define TLBSTATE_LAZY 2 @@ -159,7 +153,8 @@ static inline void reset_lazy_tlbstate(void) #endif /* SMP */ #ifndef CONFIG_PARAVIRT -#define flush_tlb_others(mask, mm, va) native_flush_tlb_others(mask, mm, va) +#define flush_tlb_others(mask, mm, start, end) \ + native_flush_tlb_others(mask, mm, start, end) #endif static inline void flush_tlb_kernel_range(unsigned long start, diff --git a/arch/x86/include/asm/uv/uv.h b/arch/x86/include/asm/uv/uv.h index 3bb9491b7659..b47c2a82ff15 100644 --- a/arch/x86/include/asm/uv/uv.h +++ b/arch/x86/include/asm/uv/uv.h @@ -15,7 +15,8 @@ extern void uv_nmi_init(void); extern void uv_system_init(void); extern const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, - unsigned long va, + unsigned long start, + unsigned end, unsigned int cpu); #else /* X86_UV */ @@ -26,7 +27,7 @@ static inline void uv_cpu_init(void) { } static inline void uv_system_init(void) { } static inline const struct cpumask * uv_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, - unsigned long va, unsigned int cpu) + unsigned long start, unsigned long end, unsigned int cpu) { return cpumask; } #endif /* X86_UV */ diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 5e57e113b72c..3b91c981a27f 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -41,7 +41,8 @@ DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) union smp_flush_state { struct { struct mm_struct *flush_mm; - unsigned long flush_va; + unsigned long flush_start; + unsigned long flush_end; raw_spinlock_t tlbstate_lock; DECLARE_BITMAP(flush_cpumask, NR_CPUS); }; @@ -156,10 +157,19 @@ void smp_invalidate_interrupt(struct pt_regs *regs) if (f->flush_mm == this_cpu_read(cpu_tlbstate.active_mm)) { if (this_cpu_read(cpu_tlbstate.state) == TLBSTATE_OK) { - if (f->flush_va == TLB_FLUSH_ALL) + if (f->flush_end == TLB_FLUSH_ALL + || !cpu_has_invlpg) local_flush_tlb(); - else - __flush_tlb_one(f->flush_va); + else if (!f->flush_end) + __flush_tlb_single(f->flush_start); + else { + unsigned long addr; + addr = f->flush_start; + while (addr < f->flush_end) { + __flush_tlb_single(addr); + addr += PAGE_SIZE; + } + } } else leave_mm(cpu); } @@ -172,7 +182,8 @@ out: } static void flush_tlb_others_ipi(const struct cpumask *cpumask, - struct mm_struct *mm, unsigned long va) + struct mm_struct *mm, unsigned long start, + unsigned long end) { unsigned int sender; union smp_flush_state *f; @@ -185,7 +196,8 @@ static void flush_tlb_others_ipi(const struct cpumask *cpumask, raw_spin_lock(&f->tlbstate_lock); f->flush_mm = mm; - f->flush_va = va; + f->flush_start = start; + f->flush_end = end; if (cpumask_andnot(to_cpumask(f->flush_cpumask), cpumask, cpumask_of(smp_processor_id()))) { /* * We have to send the IPI only to @@ -199,24 +211,26 @@ static void flush_tlb_others_ipi(const struct cpumask *cpumask, } f->flush_mm = NULL; - f->flush_va = 0; + f->flush_start = 0; + f->flush_end = 0; if (nr_cpu_ids > NUM_INVALIDATE_TLB_VECTORS) raw_spin_unlock(&f->tlbstate_lock); } void native_flush_tlb_others(const struct cpumask *cpumask, - struct mm_struct *mm, unsigned long va) + struct mm_struct *mm, unsigned long start, + unsigned long end) { if (is_uv_system()) { unsigned int cpu; cpu = smp_processor_id(); - cpumask = uv_flush_tlb_others(cpumask, mm, va, cpu); + cpumask = uv_flush_tlb_others(cpumask, mm, start, end, cpu); if (cpumask) - flush_tlb_others_ipi(cpumask, mm, va); + flush_tlb_others_ipi(cpumask, mm, start, end); return; } - flush_tlb_others_ipi(cpumask, mm, va); + flush_tlb_others_ipi(cpumask, mm, start, end); } static void __cpuinit calculate_tlb_offset(void) @@ -282,7 +296,7 @@ void flush_tlb_current_task(void) local_flush_tlb(); if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, TLB_FLUSH_ALL); + flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL); preempt_enable(); } @@ -297,12 +311,63 @@ void flush_tlb_mm(struct mm_struct *mm) leave_mm(smp_processor_id()); } if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, TLB_FLUSH_ALL); + flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL); + + preempt_enable(); +} + +#define FLUSHALL_BAR 16 + +void flush_tlb_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + struct mm_struct *mm; + + if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB) { + flush_tlb_mm(vma->vm_mm); + return; + } + + preempt_disable(); + mm = vma->vm_mm; + if (current->active_mm == mm) { + if (current->mm) { + unsigned long addr, vmflag = vma->vm_flags; + unsigned act_entries, tlb_entries = 0; + + if (vmflag & VM_EXEC) + tlb_entries = tlb_lli_4k[ENTRIES]; + else + tlb_entries = tlb_lld_4k[ENTRIES]; + + act_entries = tlb_entries > mm->total_vm ? + mm->total_vm : tlb_entries; + if ((end - start)/PAGE_SIZE > act_entries/FLUSHALL_BAR) + local_flush_tlb(); + else { + for (addr = start; addr < end; + addr += PAGE_SIZE) + __flush_tlb_single(addr); + + if (cpumask_any_but(mm_cpumask(mm), + smp_processor_id()) < nr_cpu_ids) + flush_tlb_others(mm_cpumask(mm), mm, + start, end); + preempt_enable(); + return; + } + } else { + leave_mm(smp_processor_id()); + } + } + if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) + flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL); preempt_enable(); } -void flush_tlb_page(struct vm_area_struct *vma, unsigned long va) + +void flush_tlb_page(struct vm_area_struct *vma, unsigned long start) { struct mm_struct *mm = vma->vm_mm; @@ -310,13 +375,13 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long va) if (current->active_mm == mm) { if (current->mm) - __flush_tlb_one(va); + __flush_tlb_one(start); else leave_mm(smp_processor_id()); } if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, va); + flush_tlb_others(mm_cpumask(mm), mm, start, 0UL); preempt_enable(); } diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c index 59880afa851f..f1bef8e1d633 100644 --- a/arch/x86/platform/uv/tlb_uv.c +++ b/arch/x86/platform/uv/tlb_uv.c @@ -1068,8 +1068,8 @@ static int set_distrib_bits(struct cpumask *flush_mask, struct bau_control *bcp, * done. The returned pointer is valid till preemption is re-enabled. */ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask, - struct mm_struct *mm, unsigned long va, - unsigned int cpu) + struct mm_struct *mm, unsigned long start, + unsigned end, unsigned int cpu) { int locals = 0; int remotes = 0; @@ -1112,7 +1112,7 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask, record_send_statistics(stat, locals, hubs, remotes, bau_desc); - bau_desc->payload.address = va; + bau_desc->payload.address = start; bau_desc->payload.sending_cpu = cpu; /* * uv_flush_send_and_wait returns 0 if all cpu's were messaged, diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 3a73785631ce..39ed56789f68 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1244,7 +1244,8 @@ static void xen_flush_tlb_single(unsigned long addr) } static void xen_flush_tlb_others(const struct cpumask *cpus, - struct mm_struct *mm, unsigned long va) + struct mm_struct *mm, unsigned long start, + unsigned long end) { struct { struct mmuext_op op; @@ -1256,7 +1257,7 @@ static void xen_flush_tlb_others(const struct cpumask *cpus, } *args; struct multicall_space mcs; - trace_xen_mmu_flush_tlb_others(cpus, mm, va); + trace_xen_mmu_flush_tlb_others(cpus, mm, start, end); if (cpumask_empty(cpus)) return; /* nothing to do */ @@ -1269,11 +1270,10 @@ static void xen_flush_tlb_others(const struct cpumask *cpus, cpumask_and(to_cpumask(args->mask), cpus, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), to_cpumask(args->mask)); - if (va == TLB_FLUSH_ALL) { - args->op.cmd = MMUEXT_TLB_FLUSH_MULTI; - } else { + args->op.cmd = MMUEXT_TLB_FLUSH_MULTI; + if (start != TLB_FLUSH_ALL && (end - start) <= PAGE_SIZE) { args->op.cmd = MMUEXT_INVLPG_MULTI; - args->op.arg1.linear_addr = va; + args->op.arg1.linear_addr = start; } MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF); -- cgit v1.2.1 From d8dfe60d6dcad5989c4558b753b98d657e2813c0 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:18 +0800 Subject: x86/tlb: fall back to flush all when meet a THP large page We don't need to flush large pages by PAGE_SIZE step, that just waste time. and actually, large page don't need 'invlpg' optimizing according to our micro benchmark. So, just flush whole TLB is enough for them. The following result is tested on a 2CPU * 4cores * 2HT NHM EP machine, with THP 'always' setting. Multi-thread testing, '-t' paramter is thread number: without this patch with this patch ./mprotect -t 1 14ns 13ns ./mprotect -t 2 13ns 13ns ./mprotect -t 4 12ns 11ns ./mprotect -t 8 14ns 10ns ./mprotect -t 16 28ns 28ns ./mprotect -t 32 54ns 52ns ./mprotect -t 128 200ns 200ns Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-4-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/mm/tlb.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 3b91c981a27f..184a02a4d871 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -318,12 +318,42 @@ void flush_tlb_mm(struct mm_struct *mm) #define FLUSHALL_BAR 16 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline unsigned long has_large_page(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + unsigned long addr = ALIGN(start, HPAGE_SIZE); + for (; addr < end; addr += HPAGE_SIZE) { + pgd = pgd_offset(mm, addr); + if (likely(!pgd_none(*pgd))) { + pud = pud_offset(pgd, addr); + if (likely(!pud_none(*pud))) { + pmd = pmd_offset(pud, addr); + if (likely(!pmd_none(*pmd))) + if (pmd_large(*pmd)) + return addr; + } + } + } + return 0; +} +#else +static inline unsigned long has_large_page(struct mm_struct *mm, + unsigned long start, unsigned long end) +{ + return 0; +} +#endif void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { struct mm_struct *mm; if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB) { +flush_all: flush_tlb_mm(vma->vm_mm); return; } @@ -346,6 +376,10 @@ void flush_tlb_range(struct vm_area_struct *vma, if ((end - start)/PAGE_SIZE > act_entries/FLUSHALL_BAR) local_flush_tlb(); else { + if (has_large_page(mm, start, end)) { + preempt_enable(); + goto flush_all; + } for (addr = start; addr < end; addr += PAGE_SIZE) __flush_tlb_single(addr); -- cgit v1.2.1 From c4211f42d3e66875298a5e26a75109878c80f15b Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:19 +0800 Subject: x86/tlb: add tlb_flushall_shift for specific CPU Testing show different CPU type(micro architectures and NUMA mode) has different balance points between the TLB flush all and multiple invlpg. And there also has cases the tlb flush change has no any help. This patch give a interface to let x86 vendor developers have a chance to set different shift for different CPU type. like some machine in my hands, balance points is 16 entries on Romely-EP; while it is at 8 entries on Bloomfield NHM-EP; and is 256 on IVB mobile CPU. but on model 15 core2 Xeon using invlpg has nothing help. For untested machine, do a conservative optimization, same as NHM CPU. Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-5-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/processor.h | 2 ++ arch/x86/kernel/cpu/common.c | 14 ++++++++++++-- arch/x86/kernel/cpu/intel.c | 34 ++++++++++++++++++++++++++++++++++ arch/x86/mm/tlb.c | 7 +++---- 4 files changed, 51 insertions(+), 6 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 39b2bd48dfbc..d048cad9bcad 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -72,6 +72,8 @@ extern u16 __read_mostly tlb_lli_4m[NR_INFO]; extern u16 __read_mostly tlb_lld_4k[NR_INFO]; extern u16 __read_mostly tlb_lld_2m[NR_INFO]; extern u16 __read_mostly tlb_lld_4m[NR_INFO]; +extern s8 __read_mostly tlb_flushall_shift; + /* * CPU type and hardware bug flags. Kept separately for each CPU. * Members of this structure are referenced in head.S, so think twice diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index b2016df00813..7595552600b8 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -459,16 +459,26 @@ u16 __read_mostly tlb_lld_4k[NR_INFO]; u16 __read_mostly tlb_lld_2m[NR_INFO]; u16 __read_mostly tlb_lld_4m[NR_INFO]; +/* + * tlb_flushall_shift shows the balance point in replacing cr3 write + * with multiple 'invlpg'. It will do this replacement when + * flush_tlb_lines <= active_lines/2^tlb_flushall_shift. + * If tlb_flushall_shift is -1, means the replacement will be disabled. + */ +s8 __read_mostly tlb_flushall_shift = -1; + void __cpuinit cpu_detect_tlb(struct cpuinfo_x86 *c) { if (this_cpu->c_detect_tlb) this_cpu->c_detect_tlb(c); printk(KERN_INFO "Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \ - "Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d\n", + "Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \ + "tlb_flushall_shift is 0x%x\n", tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES], tlb_lli_4m[ENTRIES], tlb_lld_4k[ENTRIES], - tlb_lld_2m[ENTRIES], tlb_lld_4m[ENTRIES]); + tlb_lld_2m[ENTRIES], tlb_lld_4m[ENTRIES], + tlb_flushall_shift); } void __cpuinit detect_ht(struct cpuinfo_x86 *c) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index ed0d512cf51b..0a4ce2980a5a 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -610,6 +610,39 @@ static void __cpuinit intel_tlb_lookup(const unsigned char desc) } } +static void __cpuinit intel_tlb_flushall_shift_set(struct cpuinfo_x86 *c) +{ + if (!cpu_has_invlpg) { + tlb_flushall_shift = -1; + return; + } + switch ((c->x86 << 8) + c->x86_model) { + case 0x60f: /* original 65 nm celeron/pentium/core2/xeon, "Merom"/"Conroe" */ + case 0x616: /* single-core 65 nm celeron/core2solo "Merom-L"/"Conroe-L" */ + case 0x617: /* current 45 nm celeron/core2/xeon "Penryn"/"Wolfdale" */ + case 0x61d: /* six-core 45 nm xeon "Dunnington" */ + tlb_flushall_shift = -1; + break; + case 0x61a: /* 45 nm nehalem, "Bloomfield" */ + case 0x61e: /* 45 nm nehalem, "Lynnfield" */ + case 0x625: /* 32 nm nehalem, "Clarkdale" */ + case 0x62c: /* 32 nm nehalem, "Gulftown" */ + case 0x62e: /* 45 nm nehalem-ex, "Beckton" */ + case 0x62f: /* 32 nm Xeon E7 */ + tlb_flushall_shift = 6; + break; + case 0x62a: /* SandyBridge */ + case 0x62d: /* SandyBridge, "Romely-EP" */ + tlb_flushall_shift = 5; + break; + case 0x63a: /* Ivybridge */ + tlb_flushall_shift = 1; + break; + default: + tlb_flushall_shift = 6; + } +} + static void __cpuinit intel_detect_tlb(struct cpuinfo_x86 *c) { int i, j, n; @@ -630,6 +663,7 @@ static void __cpuinit intel_detect_tlb(struct cpuinfo_x86 *c) for (j = 1 ; j < 16 ; j++) intel_tlb_lookup(desc[j]); } + intel_tlb_flushall_shift_set(c); } static const struct cpu_dev __cpuinitconst intel_cpu_dev = { diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 184a02a4d871..2939f2f9edbb 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -316,8 +316,6 @@ void flush_tlb_mm(struct mm_struct *mm) preempt_enable(); } -#define FLUSHALL_BAR 16 - #ifdef CONFIG_TRANSPARENT_HUGEPAGE static inline unsigned long has_large_page(struct mm_struct *mm, unsigned long start, unsigned long end) @@ -352,7 +350,7 @@ void flush_tlb_range(struct vm_area_struct *vma, { struct mm_struct *mm; - if (!cpu_has_invlpg || vma->vm_flags & VM_HUGETLB) { + if (vma->vm_flags & VM_HUGETLB || tlb_flushall_shift == -1) { flush_all: flush_tlb_mm(vma->vm_mm); return; @@ -373,7 +371,8 @@ flush_all: act_entries = tlb_entries > mm->total_vm ? mm->total_vm : tlb_entries; - if ((end - start)/PAGE_SIZE > act_entries/FLUSHALL_BAR) + if ((end - start) >> PAGE_SHIFT > + act_entries >> tlb_flushall_shift) local_flush_tlb(); else { if (has_large_page(mm, start, end)) { -- cgit v1.2.1 From 3df3212f9722c7e45c723b9ea231a04ba4dbc47c Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:20 +0800 Subject: x86/tlb: add tlb_flushall_shift knob into debugfs kernel will replace cr3 rewrite with invlpg when tlb_flush_entries <= active_tlb_entries / 2^tlb_flushall_factor if tlb_flushall_factor is -1, kernel won't do this replacement. User can modify its value according to specific CPU/applications. Thanks for Borislav providing the help message of CONFIG_DEBUG_TLBFLUSH. Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-6-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/Kconfig.debug | 19 +++++++++++++++++++ arch/x86/mm/tlb.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index e46c2147397f..b322f124ee3c 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -129,6 +129,25 @@ config DOUBLEFAULT option saves about 4k and might cause you much additional grey hair. +config DEBUG_TLBFLUSH + bool "Set upper limit of TLB entries to flush one-by-one" + depends on DEBUG_KERNEL && (X86_64 || X86_INVLPG) + ---help--- + + X86-only for now. + + This option allows the user to tune the amount of TLB entries the + kernel flushes one-by-one instead of doing a full TLB flush. In + certain situations, the former is cheaper. This is controlled by the + tlb_flushall_shift knob under /sys/kernel/debug/x86. If you set it + to -1, the code flushes the whole TLB unconditionally. Otherwise, + for positive values of it, the kernel will use single TLB entry + invalidating instructions according to the following formula: + + flush_entries <= active_tlb_entries / 2^tlb_flushall_shift + + If in doubt, say "N". + config IOMMU_DEBUG bool "Enable IOMMU debugging" depends on GART_IOMMU && DEBUG_KERNEL diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 2939f2f9edbb..5911f61e300e 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -12,6 +12,7 @@ #include #include #include +#include DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = { &init_mm, 0, }; @@ -430,3 +431,53 @@ void flush_tlb_all(void) { on_each_cpu(do_flush_tlb_all, NULL, 1); } + +#ifdef CONFIG_DEBUG_TLBFLUSH +static ssize_t tlbflush_read_file(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + char buf[32]; + unsigned int len; + + len = sprintf(buf, "%hd\n", tlb_flushall_shift); + return simple_read_from_buffer(user_buf, count, ppos, buf, len); +} + +static ssize_t tlbflush_write_file(struct file *file, + const char __user *user_buf, size_t count, loff_t *ppos) +{ + char buf[32]; + ssize_t len; + s8 shift; + + len = min(count, sizeof(buf) - 1); + if (copy_from_user(buf, user_buf, len)) + return -EFAULT; + + buf[len] = '\0'; + if (kstrtos8(buf, 0, &shift)) + return -EINVAL; + + if (shift > 64) + return -EINVAL; + + tlb_flushall_shift = shift; + return count; +} + +static const struct file_operations fops_tlbflush = { + .read = tlbflush_read_file, + .write = tlbflush_write_file, + .llseek = default_llseek, +}; + +static int __cpuinit create_tlb_flushall_shift(void) +{ + if (cpu_has_invlpg) { + debugfs_create_file("tlb_flushall_shift", S_IRUSR | S_IWUSR, + arch_debugfs_dir, NULL, &fops_tlbflush); + } + return 0; +} +late_initcall(create_tlb_flushall_shift); +#endif -- cgit v1.2.1 From 611ae8e3f5204f7480b3b405993b3352cfa16662 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:22 +0800 Subject: x86/tlb: enable tlb flush range support for x86 Not every tlb_flush execution moment is really need to evacuate all TLB entries, like in munmap, just few 'invlpg' is better for whole process performance, since it leaves most of TLB entries for later accessing. This patch also rewrite flush_tlb_range for 2 purposes: 1, split it out to get flush_blt_mm_range function. 2, clean up to reduce line breaking, thanks for Borislav's input. My micro benchmark 'mummap' http://lkml.org/lkml/2012/5/17/59 show that the random memory access on other CPU has 0~50% speed up on a 2P * 4cores * HT NHM EP while do 'munmap'. Thanks Yongjie's testing on this patch: ------------- I used Linux 3.4-RC6 w/ and w/o his patches as Xen dom0 and guest kernel. After running two benchmarks in Xen HVM guest, I found his patches brought about 1%~3% performance gain in 'kernel build' and 'netperf' testing, though the performance gain was not very stable in 'kernel build' testing. Some detailed testing results are below. Testing Environment: Hardware: Romley-EP platform Xen version: latest upstream Linux kernel: 3.4-RC6 Guest vCPU number: 8 NIC: Intel 82599 (10GB bandwidth) In 'kernel build' testing in guest: Command line | performance gain make -j 4 | 3.81% make -j 8 | 0.37% make -j 16 | -0.52% In 'netperf' testing, we tested TCP_STREAM with default socket size 16384 byte as large packet and 64 byte as small packet. I used several clients to add networking pressure, then 'netperf' server automatically generated several threads to response them. I also used large-size packet and small-size packet in the testing. Packet size | Thread number | performance gain 16384 bytes | 4 | 0.02% 16384 bytes | 8 | 2.21% 16384 bytes | 16 | 2.04% 64 bytes | 4 | 1.07% 64 bytes | 8 | 3.31% 64 bytes | 16 | 0.71% Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-8-git-send-email-alex.shi@intel.com Tested-by: Ren, Yongjie Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/tlb.h | 9 +++- arch/x86/include/asm/tlbflush.h | 17 ++++-- arch/x86/mm/tlb.c | 112 +++++++++++++++++----------------------- 3 files changed, 68 insertions(+), 70 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/tlb.h b/arch/x86/include/asm/tlb.h index 829215fef9ee..4fef20773b8f 100644 --- a/arch/x86/include/asm/tlb.h +++ b/arch/x86/include/asm/tlb.h @@ -4,7 +4,14 @@ #define tlb_start_vma(tlb, vma) do { } while (0) #define tlb_end_vma(tlb, vma) do { } while (0) #define __tlb_remove_tlb_entry(tlb, ptep, address) do { } while (0) -#define tlb_flush(tlb) flush_tlb_mm((tlb)->mm) + +#define tlb_flush(tlb) \ +{ \ + if (tlb->fullmm == 0) \ + flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end, 0UL); \ + else \ + flush_tlb_mm_range(tlb->mm, 0UL, TLB_FLUSH_ALL, 0UL); \ +} #include diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 33608d96d68b..621b959e1dbf 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -105,6 +105,13 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, __flush_tlb(); } +static inline void flush_tlb_mm_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, unsigned long vmflag) +{ + if (vma->vm_mm == current->active_mm) + __flush_tlb(); +} + static inline void native_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, unsigned long start, @@ -122,12 +129,16 @@ static inline void reset_lazy_tlbstate(void) #define local_flush_tlb() __flush_tlb() +#define flush_tlb_mm(mm) flush_tlb_mm_range(mm, 0UL, TLB_FLUSH_ALL, 0UL) + +#define flush_tlb_range(vma, start, end) \ + flush_tlb_mm_range(vma->vm_mm, start, end, vma->vm_flags) + extern void flush_tlb_all(void); extern void flush_tlb_current_task(void); -extern void flush_tlb_mm(struct mm_struct *); extern void flush_tlb_page(struct vm_area_struct *, unsigned long); -extern void flush_tlb_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end); +extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, + unsigned long end, unsigned long vmflag); #define flush_tlb() flush_tlb_current_task() diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 5911f61e300e..481737def84a 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -301,23 +301,10 @@ void flush_tlb_current_task(void) preempt_enable(); } -void flush_tlb_mm(struct mm_struct *mm) -{ - preempt_disable(); - - if (current->active_mm == mm) { - if (current->mm) - local_flush_tlb(); - else - leave_mm(smp_processor_id()); - } - if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL); - - preempt_enable(); -} - -#ifdef CONFIG_TRANSPARENT_HUGEPAGE +/* + * It can find out the THP large page, or + * HUGETLB page in tlb_flush when THP disabled + */ static inline unsigned long has_large_page(struct mm_struct *mm, unsigned long start, unsigned long end) { @@ -339,68 +326,61 @@ static inline unsigned long has_large_page(struct mm_struct *mm, } return 0; } -#else -static inline unsigned long has_large_page(struct mm_struct *mm, - unsigned long start, unsigned long end) -{ - return 0; -} -#endif -void flush_tlb_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end) -{ - struct mm_struct *mm; - if (vma->vm_flags & VM_HUGETLB || tlb_flushall_shift == -1) { -flush_all: - flush_tlb_mm(vma->vm_mm); - return; - } +void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, + unsigned long end, unsigned long vmflag) +{ + unsigned long addr; + unsigned act_entries, tlb_entries = 0; preempt_disable(); - mm = vma->vm_mm; - if (current->active_mm == mm) { - if (current->mm) { - unsigned long addr, vmflag = vma->vm_flags; - unsigned act_entries, tlb_entries = 0; + if (current->active_mm != mm) + goto flush_all; - if (vmflag & VM_EXEC) - tlb_entries = tlb_lli_4k[ENTRIES]; - else - tlb_entries = tlb_lld_4k[ENTRIES]; - - act_entries = tlb_entries > mm->total_vm ? - mm->total_vm : tlb_entries; + if (!current->mm) { + leave_mm(smp_processor_id()); + goto flush_all; + } - if ((end - start) >> PAGE_SHIFT > - act_entries >> tlb_flushall_shift) - local_flush_tlb(); - else { - if (has_large_page(mm, start, end)) { - preempt_enable(); - goto flush_all; - } - for (addr = start; addr < end; - addr += PAGE_SIZE) - __flush_tlb_single(addr); + if (end == TLB_FLUSH_ALL || tlb_flushall_shift == -1 + || vmflag == VM_HUGETLB) { + local_flush_tlb(); + goto flush_all; + } - if (cpumask_any_but(mm_cpumask(mm), - smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, - start, end); - preempt_enable(); - return; - } - } else { - leave_mm(smp_processor_id()); + /* In modern CPU, last level tlb used for both data/ins */ + if (vmflag & VM_EXEC) + tlb_entries = tlb_lli_4k[ENTRIES]; + else + tlb_entries = tlb_lld_4k[ENTRIES]; + /* Assume all of TLB entries was occupied by this task */ + act_entries = mm->total_vm > tlb_entries ? tlb_entries : mm->total_vm; + + /* tlb_flushall_shift is on balance point, details in commit log */ + if ((end - start) >> PAGE_SHIFT > act_entries >> tlb_flushall_shift) + local_flush_tlb(); + else { + if (has_large_page(mm, start, end)) { + local_flush_tlb(); + goto flush_all; } + /* flush range by one by one 'invlpg' */ + for (addr = start; addr < end; addr += PAGE_SIZE) + __flush_tlb_single(addr); + + if (cpumask_any_but(mm_cpumask(mm), + smp_processor_id()) < nr_cpu_ids) + flush_tlb_others(mm_cpumask(mm), mm, start, end); + preempt_enable(); + return; } + +flush_all: if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) flush_tlb_others(mm_cpumask(mm), mm, 0UL, TLB_FLUSH_ALL); preempt_enable(); } - void flush_tlb_page(struct vm_area_struct *vma, unsigned long start) { struct mm_struct *mm = vma->vm_mm; -- cgit v1.2.1 From 52aec3308db85f4e9f5c8b9f5dc4fbd0138c6fa4 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:23 +0800 Subject: x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR There are 32 INVALIDATE_TLB_VECTOR now in kernel. That is quite big amount of vector in IDT. But it is still not enough, since modern x86 sever has more cpu number. That still causes heavy lock contention in TLB flushing. The patch using generic smp call function to replace it. That saved 32 vector number in IDT, and resolved the lock contention in TLB flushing on large system. In the NHM EX machine 4P * 8cores * HT = 64 CPUs, hackbench pthread has 3% performance increase. Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-9-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/entry_arch.h | 9 -- arch/x86/include/asm/irq_vectors.h | 11 -- arch/x86/kernel/entry_64.S | 18 --- arch/x86/kernel/irqinit.c | 73 ----------- arch/x86/mm/tlb.c | 242 +++++++------------------------------ 5 files changed, 47 insertions(+), 306 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/entry_arch.h b/arch/x86/include/asm/entry_arch.h index 0baa628e330c..40afa0005c69 100644 --- a/arch/x86/include/asm/entry_arch.h +++ b/arch/x86/include/asm/entry_arch.h @@ -15,15 +15,6 @@ BUILD_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR) BUILD_INTERRUPT(call_function_single_interrupt,CALL_FUNCTION_SINGLE_VECTOR) BUILD_INTERRUPT(irq_move_cleanup_interrupt,IRQ_MOVE_CLEANUP_VECTOR) BUILD_INTERRUPT(reboot_interrupt,REBOOT_VECTOR) - -.irp idx,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15, \ - 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 -.if NUM_INVALIDATE_TLB_VECTORS > \idx -BUILD_INTERRUPT3(invalidate_interrupt\idx, - (INVALIDATE_TLB_VECTOR_START)+\idx, - smp_invalidate_interrupt) -.endif -.endr #endif BUILD_INTERRUPT(x86_platform_ipi, X86_PLATFORM_IPI_VECTOR) diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h index 4b4448761e88..1508e518c7e3 100644 --- a/arch/x86/include/asm/irq_vectors.h +++ b/arch/x86/include/asm/irq_vectors.h @@ -119,17 +119,6 @@ */ #define LOCAL_TIMER_VECTOR 0xef -/* up to 32 vectors used for spreading out TLB flushes: */ -#if NR_CPUS <= 32 -# define NUM_INVALIDATE_TLB_VECTORS (NR_CPUS) -#else -# define NUM_INVALIDATE_TLB_VECTORS (32) -#endif - -#define INVALIDATE_TLB_VECTOR_END (0xee) -#define INVALIDATE_TLB_VECTOR_START \ - (INVALIDATE_TLB_VECTOR_END-NUM_INVALIDATE_TLB_VECTORS+1) - #define NR_VECTORS 256 #define FPU_IRQ 13 diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 7d65133b51be..bcf28e1ce1a7 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1048,24 +1048,6 @@ apicinterrupt LOCAL_TIMER_VECTOR \ apicinterrupt X86_PLATFORM_IPI_VECTOR \ x86_platform_ipi smp_x86_platform_ipi -#ifdef CONFIG_SMP - ALIGN - INTR_FRAME -.irp idx,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15, \ - 16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 -.if NUM_INVALIDATE_TLB_VECTORS > \idx -ENTRY(invalidate_interrupt\idx) - pushq_cfi $~(INVALIDATE_TLB_VECTOR_START+\idx) - jmp .Lcommon_invalidate_interrupt0 - CFI_ADJUST_CFA_OFFSET -8 -END(invalidate_interrupt\idx) -.endif -.endr - CFI_ENDPROC -apicinterrupt INVALIDATE_TLB_VECTOR_START, \ - invalidate_interrupt0, smp_invalidate_interrupt -#endif - apicinterrupt THRESHOLD_APIC_VECTOR \ threshold_interrupt smp_threshold_interrupt apicinterrupt THERMAL_APIC_VECTOR \ diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c index 252981afd6c4..6e03b0d69138 100644 --- a/arch/x86/kernel/irqinit.c +++ b/arch/x86/kernel/irqinit.c @@ -171,79 +171,6 @@ static void __init smp_intr_init(void) */ alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt); - /* IPIs for invalidation */ -#define ALLOC_INVTLB_VEC(NR) \ - alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+NR, \ - invalidate_interrupt##NR) - - switch (NUM_INVALIDATE_TLB_VECTORS) { - default: - ALLOC_INVTLB_VEC(31); - case 31: - ALLOC_INVTLB_VEC(30); - case 30: - ALLOC_INVTLB_VEC(29); - case 29: - ALLOC_INVTLB_VEC(28); - case 28: - ALLOC_INVTLB_VEC(27); - case 27: - ALLOC_INVTLB_VEC(26); - case 26: - ALLOC_INVTLB_VEC(25); - case 25: - ALLOC_INVTLB_VEC(24); - case 24: - ALLOC_INVTLB_VEC(23); - case 23: - ALLOC_INVTLB_VEC(22); - case 22: - ALLOC_INVTLB_VEC(21); - case 21: - ALLOC_INVTLB_VEC(20); - case 20: - ALLOC_INVTLB_VEC(19); - case 19: - ALLOC_INVTLB_VEC(18); - case 18: - ALLOC_INVTLB_VEC(17); - case 17: - ALLOC_INVTLB_VEC(16); - case 16: - ALLOC_INVTLB_VEC(15); - case 15: - ALLOC_INVTLB_VEC(14); - case 14: - ALLOC_INVTLB_VEC(13); - case 13: - ALLOC_INVTLB_VEC(12); - case 12: - ALLOC_INVTLB_VEC(11); - case 11: - ALLOC_INVTLB_VEC(10); - case 10: - ALLOC_INVTLB_VEC(9); - case 9: - ALLOC_INVTLB_VEC(8); - case 8: - ALLOC_INVTLB_VEC(7); - case 7: - ALLOC_INVTLB_VEC(6); - case 6: - ALLOC_INVTLB_VEC(5); - case 5: - ALLOC_INVTLB_VEC(4); - case 4: - ALLOC_INVTLB_VEC(3); - case 3: - ALLOC_INVTLB_VEC(2); - case 2: - ALLOC_INVTLB_VEC(1); - case 1: - ALLOC_INVTLB_VEC(0); - break; - } - /* IPI for generic function call */ alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt); diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 481737def84a..2b5f506a7655 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -28,34 +28,14 @@ DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) * * More scalable flush, from Andi Kleen * - * To avoid global state use 8 different call vectors. - * Each CPU uses a specific vector to trigger flushes on other - * CPUs. Depending on the received vector the target CPUs look into - * the right array slot for the flush data. - * - * With more than 8 CPUs they are hashed to the 8 available - * vectors. The limited global vector space forces us to this right now. - * In future when interrupts are split into per CPU domains this could be - * fixed, at the cost of triggering multiple IPIs in some cases. + * Implement flush IPI by CALL_FUNCTION_VECTOR, Alex Shi */ -union smp_flush_state { - struct { - struct mm_struct *flush_mm; - unsigned long flush_start; - unsigned long flush_end; - raw_spinlock_t tlbstate_lock; - DECLARE_BITMAP(flush_cpumask, NR_CPUS); - }; - char pad[INTERNODE_CACHE_BYTES]; -} ____cacheline_internodealigned_in_smp; - -/* State is put into the per CPU data section, but padded - to a full cache line because other CPUs can access it and we don't - want false sharing in the per cpu data segment. */ -static union smp_flush_state flush_state[NUM_INVALIDATE_TLB_VECTORS]; - -static DEFINE_PER_CPU_READ_MOSTLY(int, tlb_vector_offset); +struct flush_tlb_info { + struct mm_struct *flush_mm; + unsigned long flush_start; + unsigned long flush_end; +}; /* * We cannot call mmdrop() because we are in interrupt context, @@ -74,28 +54,25 @@ void leave_mm(int cpu) EXPORT_SYMBOL_GPL(leave_mm); /* - * * The flush IPI assumes that a thread switch happens in this order: * [cpu0: the cpu that switches] * 1) switch_mm() either 1a) or 1b) * 1a) thread switch to a different mm - * 1a1) cpu_clear(cpu, old_mm->cpu_vm_mask); - * Stop ipi delivery for the old mm. This is not synchronized with - * the other cpus, but smp_invalidate_interrupt ignore flush ipis - * for the wrong mm, and in the worst case we perform a superfluous - * tlb flush. - * 1a2) set cpu mmu_state to TLBSTATE_OK - * Now the smp_invalidate_interrupt won't call leave_mm if cpu0 - * was in lazy tlb mode. - * 1a3) update cpu active_mm + * 1a1) set cpu_tlbstate to TLBSTATE_OK + * Now the tlb flush NMI handler flush_tlb_func won't call leave_mm + * if cpu0 was in lazy tlb mode. + * 1a2) update cpu active_mm * Now cpu0 accepts tlb flushes for the new mm. - * 1a4) cpu_set(cpu, new_mm->cpu_vm_mask); + * 1a3) cpu_set(cpu, new_mm->cpu_vm_mask); * Now the other cpus will send tlb flush ipis. * 1a4) change cr3. + * 1a5) cpu_clear(cpu, old_mm->cpu_vm_mask); + * Stop ipi delivery for the old mm. This is not synchronized with + * the other cpus, but flush_tlb_func ignore flush ipis for the wrong + * mm, and in the worst case we perform a superfluous tlb flush. * 1b) thread switch without mm change - * cpu active_mm is correct, cpu0 already handles - * flush ipis. - * 1b1) set cpu mmu_state to TLBSTATE_OK + * cpu active_mm is correct, cpu0 already handles flush ipis. + * 1b1) set cpu_tlbstate to TLBSTATE_OK * 1b2) test_and_set the cpu bit in cpu_vm_mask. * Atomically set the bit [other cpus will start sending flush ipis], * and test the bit. @@ -108,186 +85,61 @@ EXPORT_SYMBOL_GPL(leave_mm); * runs in kernel space, the cpu could load tlb entries for user space * pages. * - * The good news is that cpu mmu_state is local to each cpu, no + * The good news is that cpu_tlbstate is local to each cpu, no * write/read ordering problems. */ /* - * TLB flush IPI: - * + * TLB flush funcation: * 1) Flush the tlb entries if the cpu uses the mm that's being flushed. * 2) Leave the mm if we are in the lazy tlb mode. - * - * Interrupts are disabled. - */ - -/* - * FIXME: use of asmlinkage is not consistent. On x86_64 it's noop - * but still used for documentation purpose but the usage is slightly - * inconsistent. On x86_32, asmlinkage is regparm(0) but interrupt - * entry calls in with the first parameter in %eax. Maybe define - * intrlinkage? */ -#ifdef CONFIG_X86_64 -asmlinkage -#endif -void smp_invalidate_interrupt(struct pt_regs *regs) +static void flush_tlb_func(void *info) { - unsigned int cpu; - unsigned int sender; - union smp_flush_state *f; - - cpu = smp_processor_id(); - /* - * orig_rax contains the negated interrupt vector. - * Use that to determine where the sender put the data. - */ - sender = ~regs->orig_ax - INVALIDATE_TLB_VECTOR_START; - f = &flush_state[sender]; - - if (!cpumask_test_cpu(cpu, to_cpumask(f->flush_cpumask))) - goto out; - /* - * This was a BUG() but until someone can quote me the - * line from the intel manual that guarantees an IPI to - * multiple CPUs is retried _only_ on the erroring CPUs - * its staying as a return - * - * BUG(); - */ - - if (f->flush_mm == this_cpu_read(cpu_tlbstate.active_mm)) { - if (this_cpu_read(cpu_tlbstate.state) == TLBSTATE_OK) { - if (f->flush_end == TLB_FLUSH_ALL - || !cpu_has_invlpg) - local_flush_tlb(); - else if (!f->flush_end) - __flush_tlb_single(f->flush_start); - else { - unsigned long addr; - addr = f->flush_start; - while (addr < f->flush_end) { - __flush_tlb_single(addr); - addr += PAGE_SIZE; - } - } - } else - leave_mm(cpu); - } -out: - ack_APIC_irq(); - smp_mb__before_clear_bit(); - cpumask_clear_cpu(cpu, to_cpumask(f->flush_cpumask)); - smp_mb__after_clear_bit(); - inc_irq_stat(irq_tlb_count); -} + struct flush_tlb_info *f = info; -static void flush_tlb_others_ipi(const struct cpumask *cpumask, - struct mm_struct *mm, unsigned long start, - unsigned long end) -{ - unsigned int sender; - union smp_flush_state *f; - - /* Caller has disabled preemption */ - sender = this_cpu_read(tlb_vector_offset); - f = &flush_state[sender]; - - if (nr_cpu_ids > NUM_INVALIDATE_TLB_VECTORS) - raw_spin_lock(&f->tlbstate_lock); - - f->flush_mm = mm; - f->flush_start = start; - f->flush_end = end; - if (cpumask_andnot(to_cpumask(f->flush_cpumask), cpumask, cpumask_of(smp_processor_id()))) { - /* - * We have to send the IPI only to - * CPUs affected. - */ - apic->send_IPI_mask(to_cpumask(f->flush_cpumask), - INVALIDATE_TLB_VECTOR_START + sender); - - while (!cpumask_empty(to_cpumask(f->flush_cpumask))) - cpu_relax(); - } + if (f->flush_mm != this_cpu_read(cpu_tlbstate.active_mm)) + return; + + if (this_cpu_read(cpu_tlbstate.state) == TLBSTATE_OK) { + if (f->flush_end == TLB_FLUSH_ALL || !cpu_has_invlpg) + local_flush_tlb(); + else if (!f->flush_end) + __flush_tlb_single(f->flush_start); + else { + unsigned long addr; + addr = f->flush_start; + while (addr < f->flush_end) { + __flush_tlb_single(addr); + addr += PAGE_SIZE; + } + } + } else + leave_mm(smp_processor_id()); - f->flush_mm = NULL; - f->flush_start = 0; - f->flush_end = 0; - if (nr_cpu_ids > NUM_INVALIDATE_TLB_VECTORS) - raw_spin_unlock(&f->tlbstate_lock); } void native_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm, unsigned long start, unsigned long end) { + struct flush_tlb_info info; + info.flush_mm = mm; + info.flush_start = start; + info.flush_end = end; + if (is_uv_system()) { unsigned int cpu; cpu = smp_processor_id(); cpumask = uv_flush_tlb_others(cpumask, mm, start, end, cpu); if (cpumask) - flush_tlb_others_ipi(cpumask, mm, start, end); + smp_call_function_many(cpumask, flush_tlb_func, + &info, 1); return; } - flush_tlb_others_ipi(cpumask, mm, start, end); -} - -static void __cpuinit calculate_tlb_offset(void) -{ - int cpu, node, nr_node_vecs, idx = 0; - /* - * we are changing tlb_vector_offset for each CPU in runtime, but this - * will not cause inconsistency, as the write is atomic under X86. we - * might see more lock contentions in a short time, but after all CPU's - * tlb_vector_offset are changed, everything should go normal - * - * Note: if NUM_INVALIDATE_TLB_VECTORS % nr_online_nodes !=0, we might - * waste some vectors. - **/ - if (nr_online_nodes > NUM_INVALIDATE_TLB_VECTORS) - nr_node_vecs = 1; - else - nr_node_vecs = NUM_INVALIDATE_TLB_VECTORS/nr_online_nodes; - - for_each_online_node(node) { - int node_offset = (idx % NUM_INVALIDATE_TLB_VECTORS) * - nr_node_vecs; - int cpu_offset = 0; - for_each_cpu(cpu, cpumask_of_node(node)) { - per_cpu(tlb_vector_offset, cpu) = node_offset + - cpu_offset; - cpu_offset++; - cpu_offset = cpu_offset % nr_node_vecs; - } - idx++; - } -} - -static int __cpuinit tlb_cpuhp_notify(struct notifier_block *n, - unsigned long action, void *hcpu) -{ - switch (action & 0xf) { - case CPU_ONLINE: - case CPU_DEAD: - calculate_tlb_offset(); - } - return NOTIFY_OK; -} - -static int __cpuinit init_smp_flush(void) -{ - int i; - - for (i = 0; i < ARRAY_SIZE(flush_state); i++) - raw_spin_lock_init(&flush_state[i].tlbstate_lock); - - calculate_tlb_offset(); - hotcpu_notifier(tlb_cpuhp_notify, 0); - return 0; + smp_call_function_many(cpumask, flush_tlb_func, &info, 1); } -core_initcall(init_smp_flush); void flush_tlb_current_task(void) { -- cgit v1.2.1 From effee4b9b3b0aa5770bcd98de5f672b05b27703c Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Thu, 28 Jun 2012 09:02:24 +0800 Subject: x86/tlb: do flush_tlb_kernel_range by 'invlpg' This patch do flush_tlb_kernel_range by 'invlpg'. The performance pay and gain was analyzed in previous patch (x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range). In the testing: http://lkml.org/lkml/2012/6/21/10 The pay is mostly covered by long kernel path, but the gain is still quite clear, memory access in user APP can increase 30+% when kernel execute this funtion. Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1340845344-27557-10-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/tlbflush.h | 13 +++++++------ arch/x86/mm/tlb.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+), 6 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 621b959e1dbf..b5a27bd77669 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -123,6 +123,12 @@ static inline void reset_lazy_tlbstate(void) { } +static inline void flush_tlb_kernel_range(unsigned long start, + unsigned long end) +{ + flush_tlb_all(); +} + #else /* SMP */ #include @@ -139,6 +145,7 @@ extern void flush_tlb_current_task(void); extern void flush_tlb_page(struct vm_area_struct *, unsigned long); extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, unsigned long end, unsigned long vmflag); +extern void flush_tlb_kernel_range(unsigned long start, unsigned long end); #define flush_tlb() flush_tlb_current_task() @@ -168,10 +175,4 @@ static inline void reset_lazy_tlbstate(void) native_flush_tlb_others(mask, mm, start, end) #endif -static inline void flush_tlb_kernel_range(unsigned long start, - unsigned long end) -{ - flush_tlb_all(); -} - #endif /* _ASM_X86_TLBFLUSH_H */ diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 2b5f506a7655..613cd83e8c0c 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -264,6 +264,36 @@ void flush_tlb_all(void) on_each_cpu(do_flush_tlb_all, NULL, 1); } +static void do_kernel_range_flush(void *info) +{ + struct flush_tlb_info *f = info; + unsigned long addr; + + /* flush range by one by one 'invlpg' */ + for (addr = f->flush_start; addr < f->flush_end; addr += PAGE_SIZE) + __flush_tlb_single(addr); +} + +void flush_tlb_kernel_range(unsigned long start, unsigned long end) +{ + unsigned act_entries; + struct flush_tlb_info info; + + /* In modern CPU, last level tlb used for both data/ins */ + act_entries = tlb_lld_4k[ENTRIES]; + + /* Balance as user space task's flush, a bit conservative */ + if (end == TLB_FLUSH_ALL || tlb_flushall_shift == -1 || + (end - start) >> PAGE_SHIFT > act_entries >> tlb_flushall_shift) + + on_each_cpu(do_flush_tlb_all, NULL, 1); + else { + info.flush_start = start; + info.flush_end = end; + on_each_cpu(do_kernel_range_flush, &info, 1); + } +} + #ifdef CONFIG_DEBUG_TLBFLUSH static ssize_t tlbflush_read_file(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) -- cgit v1.2.1 From 7efa1c87963d23cc57ba40c07316d3e28cc75a3a Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Fri, 20 Jul 2012 09:18:23 +0800 Subject: x86/tlb: Fix build warning and crash when building for !SMP The incompatible parameter of flush_tlb_mm_range cause build warning. Fix it by correct parameter. Ingo Molnar found that this could also cause a user space crash. Reported-by: Tetsuo Handa Reported-by: Ingo Molnar Signed-off-by: Alex Shi Link: http://lkml.kernel.org/r/1342747103-19765-1-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/tlbflush.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index b5a27bd77669..74a44333545a 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -105,10 +105,10 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, __flush_tlb(); } -static inline void flush_tlb_mm_range(struct vm_area_struct *vma, +static inline void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, unsigned long end, unsigned long vmflag) { - if (vma->vm_mm == current->active_mm) + if (mm == current->active_mm) __flush_tlb(); } -- cgit v1.2.1