diff options
-rw-r--r-- | arch/blackfin/include/asm/percpu.h | 10 | ||||
-rw-r--r-- | arch/x86/include/asm/linkage.h | 16 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/amd.c | 52 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/intel.c | 25 | ||||
-rw-r--r-- | arch/x86/kernel/setup_percpu.c | 73 | ||||
-rw-r--r-- | arch/x86/kernel/smpboot.c | 78 | ||||
-rw-r--r-- | arch/x86/kernel/tlb_uv.c | 2 | ||||
-rw-r--r-- | arch/x86/mm/init.c | 2 | ||||
-rw-r--r-- | arch/x86/mm/init_32.c | 23 | ||||
-rw-r--r-- | arch/x86/mm/init_64.c | 8 | ||||
-rw-r--r-- | arch/x86/mm/ioremap.c | 21 | ||||
-rw-r--r-- | arch/x86/mm/kmmio.c | 15 | ||||
-rw-r--r-- | arch/x86/mm/memtest.c | 3 | ||||
-rw-r--r-- | include/linux/percpu.h | 60 | ||||
-rw-r--r-- | kernel/module.c | 2 | ||||
-rw-r--r-- | kernel/trace/trace_functions_graph.c | 2 | ||||
-rw-r--r-- | mm/percpu.c | 593 |
17 files changed, 631 insertions, 354 deletions
diff --git a/arch/blackfin/include/asm/percpu.h b/arch/blackfin/include/asm/percpu.h index 797c0c1..c94c7bc 100644 --- a/arch/blackfin/include/asm/percpu.h +++ b/arch/blackfin/include/asm/percpu.h @@ -3,14 +3,4 @@ #include <asm-generic/percpu.h> -#ifdef CONFIG_MODULES -#define PERCPU_MODULE_RESERVE 8192 -#else -#define PERCPU_MODULE_RESERVE 0 -#endif - -#define PERCPU_ENOUGH_ROOM \ - (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ - PERCPU_MODULE_RESERVE) - #endif /* __ARCH_BLACKFIN_PERCPU__ */ diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h index 9320e2a..a0d70b4 100644 --- a/arch/x86/include/asm/linkage.h +++ b/arch/x86/include/asm/linkage.h @@ -4,11 +4,6 @@ #undef notrace #define notrace __attribute__((no_instrument_function)) -#ifdef CONFIG_X86_64 -#define __ALIGN .p2align 4,,15 -#define __ALIGN_STR ".p2align 4,,15" -#endif - #ifdef CONFIG_X86_32 #define asmlinkage CPP_ASMLINKAGE __attribute__((regparm(0))) /* @@ -50,16 +45,25 @@ __asmlinkage_protect_n(ret, "g" (arg1), "g" (arg2), "g" (arg3), \ "g" (arg4), "g" (arg5), "g" (arg6)) -#endif +#endif /* CONFIG_X86_32 */ + +#ifdef __ASSEMBLY__ #define GLOBAL(name) \ .globl name; \ name: +#ifdef CONFIG_X86_64 +#define __ALIGN .p2align 4,,15 +#define __ALIGN_STR ".p2align 4,,15" +#endif + #ifdef CONFIG_X86_ALIGNMENT_16 #define __ALIGN .align 16,0x90 #define __ALIGN_STR ".align 16,0x90" #endif +#endif /* __ASSEMBLY__ */ + #endif /* _ASM_X86_LINKAGE_H */ diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 25423a5..f47df59 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -5,6 +5,7 @@ #include <asm/io.h> #include <asm/processor.h> #include <asm/apic.h> +#include <asm/cpu.h> #ifdef CONFIG_X86_64 # include <asm/numa_64.h> @@ -141,6 +142,55 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c) } } +static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_SMP + /* calling is from identify_secondary_cpu() ? */ + if (c->cpu_index == boot_cpu_id) + return; + + /* + * Certain Athlons might work (for various values of 'work') in SMP + * but they are not certified as MP capable. + */ + /* Athlon 660/661 is valid. */ + if ((c->x86_model == 6) && ((c->x86_mask == 0) || + (c->x86_mask == 1))) + goto valid_k7; + + /* Duron 670 is valid */ + if ((c->x86_model == 7) && (c->x86_mask == 0)) + goto valid_k7; + + /* + * Athlon 662, Duron 671, and Athlon >model 7 have capability + * bit. It's worth noting that the A5 stepping (662) of some + * Athlon XP's have the MP bit set. + * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for + * more. + */ + if (((c->x86_model == 6) && (c->x86_mask >= 2)) || + ((c->x86_model == 7) && (c->x86_mask >= 1)) || + (c->x86_model > 7)) + if (cpu_has_mp) + goto valid_k7; + + /* If we get here, not a certified SMP capable AMD system. */ + + /* + * Don't taint if we are running SMP kernel on a single non-MP + * approved Athlon + */ + WARN_ONCE(1, "WARNING: This combination of AMD" + "processors is not suitable for SMP.\n"); + if (!test_taint(TAINT_UNSAFE_SMP)) + add_taint(TAINT_UNSAFE_SMP); + +valid_k7: + ; +#endif +} + static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c) { u32 l, h; @@ -175,6 +225,8 @@ static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c) } set_cpu_cap(c, X86_FEATURE_K7); + + amd_k7_smp_check(c); } #endif diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 1a89a2b..c1c04bf 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -14,6 +14,7 @@ #include <asm/uaccess.h> #include <asm/ds.h> #include <asm/bugs.h> +#include <asm/cpu.h> #ifdef CONFIG_X86_64 #include <asm/topology.h> @@ -116,6 +117,28 @@ static void __cpuinit trap_init_f00f_bug(void) } #endif +static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_SMP + /* calling is from identify_secondary_cpu() ? */ + if (c->cpu_index == boot_cpu_id) + return; + + /* + * Mask B, Pentium, but not Pentium MMX + */ + if (c->x86 == 5 && + c->x86_mask >= 1 && c->x86_mask <= 4 && + c->x86_model <= 3) { + /* + * Remember we have B step Pentia with bugs + */ + WARN_ONCE(1, "WARNING: SMP operation may be unreliable" + "with B stepping processors.\n"); + } +#endif +} + static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) { unsigned long lo, hi; @@ -192,6 +215,8 @@ static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) #ifdef CONFIG_X86_NUMAQ numaq_tsc_disable(); #endif + + intel_smp_check(c); } #else static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c) diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index c29f301..efa615f 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -42,6 +42,19 @@ unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { }; EXPORT_SYMBOL(__per_cpu_offset); +/* + * On x86_64 symbols referenced from code should be reachable using + * 32bit relocations. Reserve space for static percpu variables in + * modules so that they are always served from the first chunk which + * is located at the percpu segment base. On x86_32, anything can + * address anywhere. No need to reserve space in the first chunk. + */ +#ifdef CONFIG_X86_64 +#define PERCPU_FIRST_CHUNK_RESERVE PERCPU_MODULE_RESERVE +#else +#define PERCPU_FIRST_CHUNK_RESERVE 0 +#endif + /** * pcpu_need_numa - determine percpu allocation needs to consider NUMA * @@ -141,7 +154,7 @@ static ssize_t __init setup_pcpu_remap(size_t static_size) { static struct vm_struct vm; pg_data_t *last; - size_t ptrs_size; + size_t ptrs_size, dyn_size; unsigned int cpu; ssize_t ret; @@ -169,12 +182,14 @@ proceed: * Currently supports only single page. Supporting multiple * pages won't be too difficult if it ever becomes necessary. */ - pcpur_size = PFN_ALIGN(static_size + PERCPU_DYNAMIC_RESERVE); + pcpur_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE + + PERCPU_DYNAMIC_RESERVE); if (pcpur_size > PMD_SIZE) { pr_warning("PERCPU: static data is larger than large page, " "can't use large page\n"); return -EINVAL; } + dyn_size = pcpur_size - static_size - PERCPU_FIRST_CHUNK_RESERVE; /* allocate pointer array and alloc large pages */ ptrs_size = PFN_ALIGN(num_possible_cpus() * sizeof(pcpur_ptrs[0])); @@ -217,8 +232,9 @@ proceed: pr_info("PERCPU: Remapped at %p with large pages, static data " "%zu bytes\n", vm.addr, static_size); - ret = pcpu_setup_first_chunk(pcpur_get_page, static_size, PMD_SIZE, - pcpur_size - static_size, vm.addr, NULL); + ret = pcpu_setup_first_chunk(pcpur_get_page, static_size, + PERCPU_FIRST_CHUNK_RESERVE, + PMD_SIZE, dyn_size, vm.addr, NULL); goto out_free_ar; enomem: @@ -241,24 +257,31 @@ static ssize_t __init setup_pcpu_remap(size_t static_size) * Embedding allocator * * The first chunk is sized to just contain the static area plus - * PERCPU_DYNAMIC_RESERVE and allocated as a contiguous area using - * bootmem allocator and used as-is without being mapped into vmalloc - * area. This enables the first chunk to piggy back on the linear - * physical PMD mapping and doesn't add any additional pressure to - * TLB. + * module and dynamic reserves, and allocated as a contiguous area + * using bootmem allocator and used as-is without being mapped into + * vmalloc area. This enables the first chunk to piggy back on the + * linear physical PMD mapping and doesn't add any additional pressure + * to TLB. Note that if the needed size is smaller than the minimum + * unit size, the leftover is returned to the bootmem allocator. */ static void *pcpue_ptr __initdata; +static size_t pcpue_size __initdata; static size_t pcpue_unit_size __initdata; static struct page * __init pcpue_get_page(unsigned int cpu, int pageno) { - return virt_to_page(pcpue_ptr + cpu * pcpue_unit_size - + ((size_t)pageno << PAGE_SHIFT)); + size_t off = (size_t)pageno << PAGE_SHIFT; + + if (off >= pcpue_size) + return NULL; + + return virt_to_page(pcpue_ptr + cpu * pcpue_unit_size + off); } static ssize_t __init setup_pcpu_embed(size_t static_size) { unsigned int cpu; + size_t dyn_size; /* * If large page isn't supported, there's no benefit in doing @@ -269,25 +292,32 @@ static ssize_t __init setup_pcpu_embed(size_t static_size) return -EINVAL; /* allocate and copy */ - pcpue_unit_size = PFN_ALIGN(static_size + PERCPU_DYNAMIC_RESERVE); - pcpue_unit_size = max_t(size_t, pcpue_unit_size, PCPU_MIN_UNIT_SIZE); + pcpue_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE + + PERCPU_DYNAMIC_RESERVE); + pcpue_unit_size = max_t(size_t, pcpue_size, PCPU_MIN_UNIT_SIZE); + dyn_size = pcpue_size - static_size - PERCPU_FIRST_CHUNK_RESERVE; + pcpue_ptr = pcpu_alloc_bootmem(0, num_possible_cpus() * pcpue_unit_size, PAGE_SIZE); if (!pcpue_ptr) return -ENOMEM; - for_each_possible_cpu(cpu) - memcpy(pcpue_ptr + cpu * pcpue_unit_size, __per_cpu_load, - static_size); + for_each_possible_cpu(cpu) { + void *ptr = pcpue_ptr + cpu * pcpue_unit_size; + + free_bootmem(__pa(ptr + pcpue_size), + pcpue_unit_size - pcpue_size); + memcpy(ptr, __per_cpu_load, static_size); + } /* we're ready, commit */ pr_info("PERCPU: Embedded %zu pages at %p, static data %zu bytes\n", - pcpue_unit_size >> PAGE_SHIFT, pcpue_ptr, static_size); + pcpue_size >> PAGE_SHIFT, pcpue_ptr, static_size); return pcpu_setup_first_chunk(pcpue_get_page, static_size, - pcpue_unit_size, - pcpue_unit_size - static_size, pcpue_ptr, - NULL); + PERCPU_FIRST_CHUNK_RESERVE, + pcpue_unit_size, dyn_size, + pcpue_ptr, NULL); } /* @@ -344,7 +374,8 @@ static ssize_t __init setup_pcpu_4k(size_t static_size) pr_info("PERCPU: Allocated %d 4k pages, static data %zu bytes\n", pcpu4k_nr_static_pages, static_size); - ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, 0, 0, NULL, + ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, + PERCPU_FIRST_CHUNK_RESERVE, -1, -1, NULL, pcpu4k_populate_pte); goto out_free_ar; diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 249334f..ef7d101 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -114,10 +114,6 @@ EXPORT_PER_CPU_SYMBOL(cpu_info); atomic_t init_deasserted; - -/* Set if we find a B stepping CPU */ -static int __cpuinitdata smp_b_stepping; - #if defined(CONFIG_NUMA) && defined(CONFIG_X86_32) /* which logical CPUs are on which nodes */ @@ -271,8 +267,6 @@ static void __cpuinit smp_callin(void) cpumask_set_cpu(cpuid, cpu_callin_mask); } -static int __cpuinitdata unsafe_smp; - /* * Activate a secondary processor. */ @@ -340,76 +334,6 @@ notrace static void __cpuinit start_secondary(void *unused) cpu_idle(); } -static void __cpuinit smp_apply_quirks(struct cpuinfo_x86 *c) -{ - /* - * Mask B, Pentium, but not Pentium MMX - */ - if (c->x86_vendor == X86_VENDOR_INTEL && - c->x86 == 5 && - c->x86_mask >= 1 && c->x86_mask <= 4 && - c->x86_model <= 3) - /* - * Remember we have B step Pentia with bugs - */ - smp_b_stepping = 1; - - /* - * Certain Athlons might work (for various values of 'work') in SMP - * but they are not certified as MP capable. - */ - if ((c->x86_vendor == X86_VENDOR_AMD) && (c->x86 == 6)) { - - if (num_possible_cpus() == 1) - goto valid_k7; - - /* Athlon 660/661 is valid. */ - if ((c->x86_model == 6) && ((c->x86_mask == 0) || - (c->x86_mask == 1))) - goto valid_k7; - - /* Duron 670 is valid */ - if ((c->x86_model == 7) && (c->x86_mask == 0)) - goto valid_k7; - - /* - * Athlon 662, Duron 671, and Athlon >model 7 have capability - * bit. It's worth noting that the A5 stepping (662) of some - * Athlon XP's have the MP bit set. - * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for - * more. - */ - if (((c->x86_model == 6) && (c->x86_mask >= 2)) || - ((c->x86_model == 7) && (c->x86_mask >= 1)) || - (c->x86_model > 7)) - if (cpu_has_mp) - goto valid_k7; - - /* If we get here, not a certified SMP capable AMD system. */ - unsafe_smp = 1; - } - -valid_k7: - ; -} - -static void __cpuinit smp_checks(void) -{ - if (smp_b_stepping) - printk(KERN_WARNING "WARNING: SMP operation may be unreliable" - "with B stepping processors.\n"); - - /* - * Don't taint if we are running SMP kernel on a single non-MP - * approved Athlon - */ - if (unsafe_smp && num_online_cpus() > 1) { - printk(KERN_INFO "WARNING: This combination of AMD" - "processors is not suitable for SMP.\n"); - add_taint(TAINT_UNSAFE_SMP); - } -} - /* * The bootstrap kernel entry code has set these up. Save them for * a given CPU @@ -423,7 +347,6 @@ void __cpuinit smp_store_cpu_info(int id) c->cpu_index = id; if (id != 0) identify_secondary_cpu(c); - smp_apply_quirks(c); } @@ -1193,7 +1116,6 @@ void __init native_smp_cpus_done(unsigned int max_cpus) pr_debug("Boot done.\n"); impress_friends(); - smp_checks(); #ifdef CONFIG_X86_IO_APIC setup_ioapic_dest(); #endif diff --git a/arch/x86/kernel/tlb_uv.c b/arch/x86/kernel/tlb_uv.c index f04549a..d038b9c 100644 --- a/arch/x86/kernel/tlb_uv.c +++ b/arch/x86/kernel/tlb_uv.c @@ -314,8 +314,6 @@ const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask, int locals = 0; struct bau_desc *bau_desc; - WARN_ON(!in_atomic()); - cpumask_andnot(flush_mask, cpumask, cpumask_of(cpu)); uv_cpu = uv_blade_processor_id(); diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 6d63e3d..15219e0 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -134,8 +134,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, { unsigned long page_size_mask = 0; unsigned long start_pfn, end_pfn; + unsigned long ret = 0; unsigned long pos; - unsigned long ret; struct map_range mr[NR_RANGE_MR]; int nr_range, i; diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index d7f5060..749559e 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -806,11 +806,6 @@ static unsigned long __init setup_node_bootmem(int nodeid, { unsigned long bootmap_size; - if (start_pfn > max_low_pfn) - return bootmap; - if (end_pfn > max_low_pfn) - end_pfn = max_low_pfn; - /* don't touch min_low_pfn */ bootmap_size = init_bootmem_node(NODE_DATA(nodeid), bootmap >> PAGE_SHIFT, @@ -843,13 +838,23 @@ void __init setup_bootmem_allocator(void) max_pfn_mapped<<PAGE_SHIFT); printk(KERN_INFO " low ram: 0 - %08lx\n", max_low_pfn<<PAGE_SHIFT); + for_each_online_node(nodeid) { + unsigned long start_pfn, end_pfn; + #ifdef CONFIG_NEED_MULTIPLE_NODES - for_each_online_node(nodeid) - bootmap = setup_node_bootmem(nodeid, node_start_pfn[nodeid], - node_end_pfn[nodeid], bootmap); + start_pfn = node_start_pfn[nodeid]; + end_pfn = node_end_pfn[nodeid]; + if (start_pfn > max_low_pfn) + continue; + if (end_pfn > max_low_pfn) + end_pfn = max_low_pfn; #else - bootmap = setup_node_bootmem(0, 0, max_low_pfn, bootmap); + start_pfn = 0; + end_pfn = max_low_pfn; #endif + bootmap = setup_node_bootmem(nodeid, start_pfn, end_pfn, + bootmap); + } after_bootmem = 1; } diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 66d6be8..1753e80 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -85,7 +85,7 @@ early_param("gbpages", parse_direct_gbpages_on); pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP; EXPORT_SYMBOL_GPL(__supported_pte_mask); -static int do_not_nx __cpuinitdata; +static int disable_nx __cpuinitdata; /* * noexec=on|off @@ -100,9 +100,9 @@ static int __init nonx_setup(char *str) return -EINVAL; if (!strncmp(str, "on", 2)) { __supported_pte_mask |= _PAGE_NX; - do_not_nx = 0; + disable_nx = 0; } else if (!strncmp(str, "off", 3)) { - do_not_nx = 1; + disable_nx = 1; __supported_pte_mask &= ~_PAGE_NX; } return 0; @@ -114,7 +114,7 @@ void __cpuinit check_efer(void) unsigned long efer; rdmsrl(MSR_EFER, efer); - if (!(efer & EFER_NX) || do_not_nx) + if (!(efer & EFER_NX) || disable_nx) __supported_pte_mask &= ~_PAGE_NX; } diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 62773ab..aca924a 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -87,6 +87,8 @@ bool __virt_addr_valid(unsigned long x) return false; if (__vmalloc_start_set && is_vmalloc_addr((void *) x)) return false; + if (x >= FIXADDR_START) + return false; return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT); } EXPORT_SYMBOL(__virt_addr_valid); @@ -504,13 +506,19 @@ static inline pte_t * __init early_ioremap_pte(unsigned long addr) return &bm_pte[pte_index(addr)]; } +static unsigned long slot_virt[FIX_BTMAPS_SLOTS] __initdata; + void __init early_ioremap_init(void) { pmd_t *pmd; + int i; if (early_ioremap_debug) printk(KERN_INFO "early_ioremap_init()\n"); + for (i = 0; i < FIX_BTMAPS_SLOTS; i++) + slot_virt[i] = fix_to_virt(FIX_BTMAP_BEGIN - NR_FIX_BTMAPS*i); + pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); memset(bm_pte, 0, sizeof(bm_pte)); pmd_populate_kernel(&init_mm, pmd, bm_pte); @@ -577,6 +585,7 @@ static inline void __init early_clear_fixmap(enum fixed_addresses idx) static void __iomem *prev_map[FIX_BTMAPS_SLOTS] __initdata; static unsigned long prev_size[FIX_BTMAPS_SLOTS] __initdata; + static int __init check_early_ioremap_leak(void) { int count = 0; @@ -598,7 +607,8 @@ static int __init check_early_ioremap_leak(void) } late_initcall(check_early_ioremap_leak); -static void __init __iomem *__early_ioremap(unsigned long phys_addr, unsigned long size, pgprot_t prot) +static void __init __iomem * +__early_ioremap(unsigned long phys_addr, unsigned long size, pgprot_t prot) { unsigned long offset, last_addr; unsigned int nrpages; @@ -664,9 +674,9 @@ static void __init __iomem *__early_ioremap(unsigned long phys_addr, unsigned lo --nrpages; } if (early_ioremap_debug) - printk(KERN_CONT "%08lx + %08lx\n", offset, fix_to_virt(idx0)); + printk(KERN_CONT "%08lx + %08lx\n", offset, slot_virt[slot]); - prev_map[slot] = (void __iomem *)(offset + fix_to_virt(idx0)); + prev_map[slot] = (void __iomem *)(offset + slot_virt[slot]); return prev_map[slot]; } @@ -734,8 +744,3 @@ void __init early_iounmap(void __iomem *addr, unsigned long size) } prev_map[slot] = NULL; } - -void __this_fixmap_does_not_exist(void) -{ - WARN_ON(1); -} diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c index 9f20503..6a518dd 100644 --- a/arch/x86/mm/kmmio.c +++ b/arch/x86/mm/kmmio.c @@ -451,23 +451,24 @@ static void rcu_free_kmmio_fault_pages(struct rcu_head *head) static void remove_kmmio_fault_pages(struct rcu_head *head) { - struct kmmio_delayed_release *dr = container_of( - head, - struct kmmio_delayed_release, - rcu); + struct kmmio_delayed_release *dr = + container_of(head, struct kmmio_delayed_release, rcu); struct kmmio_fault_page *p = dr->release_list; struct kmmio_fault_page **prevp = &dr->release_list; unsigned long flags; + spin_lock_irqsave(&kmmio_lock, flags); while (p) { - if (!p->count) + if (!p->count) { list_del_rcu(&p->list); - else + prevp = &p->release_next; + } else { *prevp = p->release_next; - prevp = &p->release_next; + } p = p->release_next; } spin_unlock_irqrestore(&kmmio_lock, flags); + /* This is the real RCU destroy call. */ call_rcu(&dr->rcu, rcu_free_kmmio_fault_pages); } diff --git a/arch/x86/mm/memtest.c b/arch/x86/mm/memtest.c index 0bcd788..605c8be 100644 --- a/arch/x86/mm/memtest.c +++ b/arch/x86/mm/memtest.c @@ -100,6 +100,9 @@ static int __init parse_memtest(char *arg) { if (arg) memtest_pattern = simple_strtoul(arg, NULL, 0); + else + memtest_pattern = ARRAY_SIZE(patterns); + return 0; } diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 545b068..54a968b 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -5,6 +5,7 @@ #include <linux/slab.h> /* For kmalloc() */ #include <linux/smp.h> #include <linux/cpumask.h> +#include <linux/pfn.h> #include <asm/percpu.h> @@ -52,17 +53,18 @@ #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) -/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */ -#ifndef PERCPU_ENOUGH_ROOM +/* enough to cover all DEFINE_PER_CPUs in modules */ #ifdef CONFIG_MODULES -#define PERCPU_MODULE_RESERVE 8192 +#define PERCPU_MODULE_RESERVE (8 << 10) #else -#define PERCPU_MODULE_RESERVE 0 +#define PERCPU_MODULE_RESERVE 0 #endif +#ifndef PERCPU_ENOUGH_ROOM #define PERCPU_ENOUGH_ROOM \ - (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE) -#endif /* PERCPU_ENOUGH_ROOM */ + (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ + PERCPU_MODULE_RESERVE) +#endif /* * Must be an lvalue. Since @var must be a simple identifier, @@ -79,35 +81,24 @@ #ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA /* minimum unit size, also is the maximum supported allocation size */ -#define PCPU_MIN_UNIT_SIZE (16UL << PAGE_SHIFT) +#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10) /* * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy - * back on the first chunk if arch is manually allocating and mapping - * it for faster access (as a part of large page mapping for example). - * Note that dynamic percpu allocator covers both static and dynamic - * areas, so these values are bigger than PERCPU_MODULE_RESERVE. + * back on the first chunk for dynamic percpu allocation if arch is + * manually allocating and mapping it for faster access (as a part of + * large page mapping for example). * - * On typical configuration with modules, the following values leave - * about 8k of free space on the first chunk after boot on both x86_32 - * and 64 when module support is enabled. When module support is - * disabled, it's much tighter. + * The following values give between one and two pages of free space + * after typical minimal boot (2-way SMP, single disk and NIC) with + * both defconfig and a distro config on x86_64 and 32. More + * intelligent way to determine this would be nice. */ -#ifndef PERCPU_DYNAMIC_RESERVE -# if BITS_PER_LONG > 32 -# ifdef CONFIG_MODULES -# define PERCPU_DYNAMIC_RESERVE (6 << PAGE_SHIFT) -# else -# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT) -# endif -# else -# ifdef CONFIG_MODULES -# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT) -# else -# define PERCPU_DYNAMIC_RESERVE (2 << PAGE_SHIFT) -# endif -# endif -#endif /* PERCPU_DYNAMIC_RESERVE */ +#if BITS_PER_LONG > 32 +#define PERCPU_DYNAMIC_RESERVE (20 << 10) +#else +#define PERCPU_DYNAMIC_RESERVE (12 << 10) +#endif extern void *pcpu_base_addr; @@ -115,9 +106,10 @@ typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno); typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr); extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, - size_t static_size, size_t unit_size, - size_t free_size, void *base_addr, - pcpu_populate_pte_fn_t populate_pte_fn); + size_t static_size, size_t reserved_size, + ssize_t unit_size, ssize_t dyn_size, + void *base_addr, + pcpu_populate_pte_fn_t populate_pte_fn); /* * Use this to get to a cpu's version of the per-cpu object @@ -126,6 +118,8 @@ extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, */ #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) +extern void *__alloc_reserved_percpu(size_t size, size_t align); + #else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ struct percpu_data { diff --git a/kernel/module.c b/kernel/module.c index 90a6d63..8b742f2b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -381,7 +381,7 @@ static void *percpu_modalloc(unsigned long size, unsigned long align, align = PAGE_SIZE; } - ptr = __alloc_percpu(size, align); + ptr = __alloc_reserved_percpu(size, align); if (!ptr) printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n", size); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 453ebd3..35257be 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -837,7 +837,7 @@ static void graph_trace_open(struct trace_iterator *iter) static void graph_trace_close(struct trace_iterator *iter) { - percpu_free(iter->private); + free_percpu(iter->private); } static struct tracer graph_trace __read_mostly = { diff --git a/mm/percpu.c b/mm/percpu.c index 3d0f545..bfe6a3a 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -62,7 +62,9 @@ #include <linux/pfn.h> #include <linux/rbtree.h> #include <linux/slab.h> +#include <linux/spinlock.h> #include <linux/vmalloc.h> +#include <linux/workqueue.h> #include <asm/cacheflush.h> #include <asm/tlbflush.h> @@ -80,7 +82,8 @@ struct pcpu_chunk { int map_alloc; /* # of map entries allocated */ int *map; /* allocation map */ bool immutable; /* no [de]population allowed */ - struct page *page[]; /* #cpus * UNIT_PAGES */ + struct page **page; /* points to page array */ + struct page *page_ar[]; /* #cpus * UNIT_PAGES */ }; static int pcpu_unit_pages __read_mostly; @@ -93,28 +96,42 @@ static size_t pcpu_chunk_struct_size __read_mostly; void *pcpu_base_addr __read_mostly; EXPORT_SYMBOL_GPL(pcpu_base_addr); -/* the size of kernel static area */ -static int pcpu_static_size __read_mostly; +/* optional reserved chunk, only accessible for reserved allocations */ +static struct pcpu_chunk *pcpu_reserved_chunk; +/* offset limit of the reserved chunk */ +static int pcpu_reserved_chunk_limit; /* - * One mutex to rule them all. - * - * The following mutex is grabbed in the outermost public alloc/free - * interface functions and released only when the operation is - * complete. As such, every function in this file other than the - * outermost functions are called under pcpu_mutex. - * - * It can easily be switched to use spinlock such that only the area - * allocation and page population commit are protected with it doing - * actual [de]allocation without holding any lock. However, given - * what this allocator does, I think it's better to let them run - * sequentially. + * Synchronization rules. + * + * There are two locks - pcpu_alloc_mutex and pcpu_lock. The former + * protects allocation/reclaim paths, chunks and chunk->page arrays. + * The latter is a spinlock and protects the index data structures - + * chunk slots, rbtree, chunks and area maps in chunks. + * + * During allocation, pcpu_alloc_mutex is kept locked all the time and + * pcpu_lock is grabbed and released as necessary. All actual memory + * allocations are done using GFP_KERNEL with pcpu_lock released. + * + * Free path accesses and alters only the index data structures, so it + * can be safely called from atomic context. When memory needs to be + * returned to the system, free path schedules reclaim_work which + * grabs both pcpu_alloc_mutex and pcpu_lock, unlinks chunks to be + * reclaimed, release both locks and frees the chunks. Note that it's + * necessary to grab both locks to remove a chunk from circulation as + * allocation path might be referencing the chunk with only + * pcpu_alloc_mutex locked. */ -static DEFINE_MUTEX(pcpu_mutex); +static DEFINE_MUTEX(pcpu_alloc_mutex); /* protects whole alloc and reclaim */ +static DEFINE_SPINLOCK(pcpu_lock); /* protects index data structures */ static struct list_head *pcpu_slot __read_mostly; /* chunk list slots */ static struct rb_root pcpu_addr_root = RB_ROOT; /* chunks by address */ +/* reclaim work to release fully free chunks, scheduled from free path */ +static void pcpu_reclaim(struct work_struct *work); +static DECLARE_WORK(pcpu_reclaim_work, pcpu_reclaim); + static int __pcpu_size_to_slot(int size) { int highbit = fls(size); /* size is in bytes */ @@ -161,39 +178,44 @@ static bool pcpu_chunk_page_occupied(struct pcpu_chunk *chunk, } /** - * pcpu_realloc - versatile realloc - * @p: the current pointer (can be NULL for new allocations) - * @size: the current size in bytes (can be 0 for new allocations) - * @new_size: the wanted new size in bytes (can be 0 for free) + * pcpu_mem_alloc - allocate memory + * @size: bytes to allocate + * + * Allocate @size bytes. If @size is smaller than PAGE_SIZE, + * kzalloc() is used; otherwise, vmalloc() is used. The returned + * memory is always zeroed. * - * More robust realloc which can be used to allocate, resize or free a - * memory area of arbitrary size. If the needed size goes over - * PAGE_SIZE, kernel VM is used. + * CONTEXT: + * Does GFP_KERNEL allocation. * * RETURNS: - * The new pointer on success, NULL on failure. + * Pointer to the allocated area on success, NULL on failure. */ -static void *pcpu_realloc(void *p, size_t size, size_t new_size) +static void *pcpu_mem_alloc(size_t size) { - void *new; - - if (new_size <= PAGE_SIZE) - new = kmalloc(new_size, GFP_KERNEL); - else - new = vmalloc(new_size); - if (new_size && !new) - return NULL; - - memcpy(new, p, min(size, new_size)); - if (new_size > size) - memset(new + size, 0, new_size - size); + if (size <= PAGE_SIZE) + return kzalloc(size, GFP_KERNEL); + else { + void *ptr = vmalloc(size); + if (ptr) + memset(ptr, 0, size); + return ptr; + } +} +/** + * pcpu_mem_free - free memory + * @ptr: memory to free + * @size: size of the area + * + * Free @ptr. @ptr should have been allocated using pcpu_mem_alloc(). + */ +static void pcpu_mem_free(void *ptr, size_t size) +{ if (size <= PAGE_SIZE) - kfree(p); + kfree(ptr); else - vfree(p); - - return new; + vfree(ptr); } /** @@ -203,13 +225,17 @@ static void *pcpu_realloc(void *p, size_t size, size_t new_size) * * This function is called after an allocation or free changed @chunk. * New slot according to the changed state is determined and @chunk is - * moved to the slot. + * moved to the slot. Note that the reserved chunk is never put on + * chunk slots. + * + * CONTEXT: + * pcpu_lock. */ static void pcpu_chunk_relocate(struct pcpu_chunk *chunk, int oslot) { int nslot = pcpu_chunk_slot(chunk); - if (oslot != nslot) { + if (chunk != pcpu_reserved_chunk && oslot != nslot) { if (oslot < nslot) list_move(&chunk->list, &pcpu_slot[nslot]); else @@ -249,6 +275,9 @@ static struct rb_node **pcpu_chunk_rb_search(void *addr, * searchs for the chunk with the highest start address which isn't * beyond @addr. * + * CONTEXT: + * pcpu_lock. + * * RETURNS: * The address of the found chunk. */ @@ -257,6 +286,15 @@ static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) struct rb_node *n, *parent; struct pcpu_chunk *chunk; + /* is it in the reserved chunk? */ + if (pcpu_reserved_chunk) { + void *start = pcpu_reserved_chunk->vm->addr; + + if (addr >= start && addr < start + pcpu_reserved_chunk_limit) + return pcpu_reserved_chunk; + } + + /* nah... search the regular ones */ n = *pcpu_chunk_rb_search(addr, &parent); if (!n) { /* no exactly matching chunk, the parent is the closest */ @@ -280,6 +318,9 @@ static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) * @new: chunk to insert * * Insert @new into address rb tree. + * + * CONTEXT: + * pcpu_lock. */ static void pcpu_chunk_addr_insert(struct pcpu_chunk *new) { @@ -292,6 +333,66 @@ static void pcpu_chunk_addr_insert(struct pcpu_chunk *new) } /** + * pcpu_extend_area_map - extend area map for allocation + * @chunk: target chunk + * + * Extend area map of @chunk so that it can accomodate an allocation. + * A single allocation can split an area into three areas, so this + * function makes sure that @chunk->map has at least two extra slots. + * + * CONTEXT: + * pcpu_alloc_mutex, pcpu_lock. pcpu_lock is released and reacquired + * if area map is extended. + * + * RETURNS: + * 0 if noop, 1 if successfully extended, -errno on failure. + */ +static int pcpu_extend_area_map(struct pcpu_chunk *chunk) +{ + int new_alloc; + int *new; + size_t size; + + /* has enough? */ + if (chunk->map_alloc >= chunk->map_used + 2) + return 0; + + spin_unlock_irq(&pcpu_lock); + + new_alloc = PCPU_DFL_MAP_ALLOC; + while (new_alloc < chunk->map_used + 2) + new_alloc *= 2; + + new = pcpu_mem_alloc(new_alloc * sizeof(new[0])); + if (!new) { + spin_lock_irq(&pcpu_lock); + return -ENOMEM; + } + + /* + * Acquire pcpu_lock and switch to new area map. Only free + * could have happened inbetween, so map_used couldn't have + * grown. + */ + spin_lock_irq(&pcpu_lock); + BUG_ON(new_alloc < chunk->map_used + 2); + + size = chunk->map_alloc * sizeof(chunk->map[0]); + memcpy(new, chunk->map, size); + + /* + * map_alloc < PCPU_DFL_MAP_ALLOC indicates that the chunk is + * one of the first chunks and still using static map. + */ + if (chunk->map_alloc >= PCPU_DFL_MAP_ALLOC) + pcpu_mem_free(chunk->map, size); + + chunk->map_alloc = new_alloc; + chunk->map = new; + return 0; +} + +/** * pcpu_split_block - split a map block * @chunk: chunk of interest * @i: index of map block to split @@ -306,33 +407,19 @@ static void pcpu_chunk_addr_insert(struct pcpu_chunk *new) * depending on @head, is reduced by @tail bytes and @tail byte block * is inserted after the target block. * - * RETURNS: - * 0 on success, -errno on failure. + * @chunk->map must have enough free slots to accomodate the split. + * + * CONTEXT: + * pcpu_lock. */ -static int pcpu_split_block(struct pcpu_chunk *chunk, int i, int head, int tail) +static void pcpu_split_block(struct pcpu_chunk *chunk, int i, + int head, int tail) { int nr_extra = !!head + !!tail; - int target = chunk->map_used + nr_extra; - - /* reallocation required? */ - if (chunk->map_alloc < target) { - int new_alloc = chunk->map_alloc; - int *new; - while (new_alloc < target) - new_alloc *= 2; + BUG_ON(chunk->map_alloc < chunk->map_used + nr_extra); - new = pcpu_realloc(chunk->map, - chunk->map_alloc * sizeof(new[0]), - new_alloc * sizeof(new[0])); - if (!new) - return -ENOMEM; - - chunk->map_alloc = new_alloc; - chunk->map = new; - } - - /* insert a new subblock */ + /* insert new subblocks */ memmove(&chunk->map[i + nr_extra], &chunk->map[i], sizeof(chunk->map[0]) * (chunk->map_used - i)); chunk->map_used += nr_extra; @@ -345,7 +432,6 @@ static int pcpu_split_block(struct pcpu_chunk *chunk, int i, int head, int tail) chunk->map[i++] -= tail; chunk->map[i] = tail; } - return 0; } /** @@ -358,8 +444,14 @@ static int pcpu_split_block(struct pcpu_chunk *chunk, int i, int head, int tail) * Note that this function only allocates the offset. It doesn't * populate or map the area. * + * @chunk->map must have at least two free slots. + * + * CONTEXT: + * pcpu_lock. + * * RETURNS: - * Allocated offset in @chunk on success, -errno on failure. + * Allocated offset in @chunk on success, -1 if no matching area is + * found. */ static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) { @@ -367,22 +459,6 @@ static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) int max_contig = 0; int i, off; - /* - * The static chunk initially doesn't have map attached - * because kmalloc wasn't available during init. Give it one. - */ - if (unlikely(!chunk->map)) { - chunk->map = pcpu_realloc(NULL, 0, - PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); - if (!chunk->map) - return -ENOMEM; - - chunk->map_alloc = PCPU_DFL_MAP_ALLOC; - chunk->map[chunk->map_used++] = -pcpu_static_size; - if (chunk->free_size) - chunk->map[chunk->map_used++] = chunk->free_size; - } - for (i = 0, off = 0; i < chunk->map_used; off += abs(chunk->map[i++])) { bool is_last = i + 1 == chunk->map_used; int head, tail; @@ -423,8 +499,7 @@ static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) /* split if warranted */ if (head || tail) { - if (pcpu_split_block(chunk, i, head, tail)) - return -ENOMEM; + pcpu_split_block(chunk, i, head, tail); if (head) { i++; off += head; @@ -451,14 +526,8 @@ static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) chunk->contig_hint = max_contig; /* fully scanned */ pcpu_chunk_relocate(chunk, oslot); - /* - * Tell the upper layer that this chunk has no area left. - * Note that this is not an error condition but a notification - * to upper layer that it needs to look at other chunks. - * -ENOSPC is chosen as it isn't used in memory subsystem and - * matches the meaning in a way. - */ - return -ENOSPC; + /* tell the upper layer that this chunk has no matching area */ + return -1; } /** @@ -469,6 +538,9 @@ static int pcpu_alloc_area(struct pcpu_chunk *chunk, int size, int align) * Free area starting from @freeme to @chunk. Note that this function * only modifies the allocation map. It doesn't depopulate or unmap * the area. + * + * CONTEXT: + * pcpu_lock. */ static void pcpu_free_area(struct pcpu_chunk *chunk, int freeme) { @@ -554,6 +626,9 @@ static void pcpu_unmap(struct pcpu_chunk *chunk, int page_start, int page_end, * For each cpu, depopulate and unmap pages [@page_start,@page_end) * from @chunk. If @flush is true, vcache is flushed before unmapping * and tlb after. + * + * CONTEXT: + * pcpu_alloc_mutex. */ static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size, bool flush) @@ -632,6 +707,9 @@ static int pcpu_map(struct pcpu_chunk *chunk, int page_start, int page_end) * * For each cpu, populate and map pages [@page_start,@page_end) into * @chunk. The area is cleared on return. + * + * CONTEXT: + * pcpu_alloc_mutex, does GFP_KERNEL allocation. */ static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size) { @@ -686,7 +764,7 @@ static void free_pcpu_chunk(struct pcpu_chunk *chunk) return; if (chunk->vm) free_vm_area(chunk->vm); - pcpu_realloc(chunk->map, chunk->map_alloc * sizeof(chunk->map[0]), 0); + pcpu_mem_free(chunk->map, chunk->map_alloc * sizeof(chunk->map[0])); kfree(chunk); } @@ -698,10 +776,10 @@ static struct pcpu_chunk *alloc_pcpu_chunk(void) if (!chunk) return NULL; - chunk->map = pcpu_realloc(NULL, 0, - PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); + chunk->map = pcpu_mem_alloc(PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); chunk->map_alloc = PCPU_DFL_MAP_ALLOC; chunk->map[chunk->map_used++] = pcpu_unit_size; + chunk->page = chunk->page_ar; chunk->vm = get_vm_area(pcpu_chunk_size, GFP_KERNEL); if (!chunk->vm) { @@ -717,19 +795,21 @@ static struct pcpu_chunk *alloc_pcpu_chunk(void) } /** - * __alloc_percpu - allocate percpu area + * pcpu_alloc - the percpu allocator * @size: size of area to allocate in bytes * @align: alignment of area (max PAGE_SIZE) + * @reserved: allocate from the reserved chunk if available * - * Allocate percpu area of @size bytes aligned at @align. Might - * sleep. Might trigger writeouts. + * Allocate percpu area of @size bytes aligned at @align. + * + * CONTEXT: + * Does GFP_KERNEL allocation. * * RETURNS: * Percpu pointer to the allocated area on success, NULL on failure. */ -void *__alloc_percpu(size_t size, size_t align) +static void *pcpu_alloc(size_t size, size_t align, bool reserved) { - void *ptr = NULL; struct pcpu_chunk *chunk; int slot, off; @@ -739,90 +819,192 @@ void *__alloc_percpu(size_t size, size_t align) return NULL; } - mutex_lock(&pcpu_mutex); + mutex_lock(&pcpu_alloc_mutex); + spin_lock_irq(&pcpu_lock); + + /* serve reserved allocations from the reserved chunk if available */ + if (reserved && pcpu_reserved_chunk) { + chunk = pcpu_reserved_chunk; + if (size > chunk->contig_hint || + pcpu_extend_area_map(chunk) < 0) + goto fail_unlock; + off = pcpu_alloc_area(chunk, size, align); + if (off >= 0) + goto area_found; + goto fail_unlock; + } - /* allocate area */ +restart: + /* search through normal chunks */ for (slot = pcpu_size_to_slot(size); slot < pcpu_nr_slots; slot++) { list_for_each_entry(chunk, &pcpu_slot[slot], list) { if (size > chunk->contig_hint) continue; + + switch (pcpu_extend_area_map(chunk)) { + case 0: + break; + case 1: + goto restart; /* pcpu_lock dropped, restart */ + default: + goto fail_unlock; + } + off = pcpu_alloc_area(chunk, size, align); if (off >= 0) goto area_found; - if (off != -ENOSPC) - goto out_unlock; } } /* hmmm... no space left, create a new chunk */ + spin_unlock_irq(&pcpu_lock); + chunk = alloc_pcpu_chunk(); if (!chunk) - goto out_unlock; + goto fail_unlock_mutex; + + spin_lock_irq(&pcpu_lock); pcpu_chunk_relocate(chunk, -1); pcpu_chunk_addr_insert(chunk); - - off = pcpu_alloc_area(chunk, size, align); - if (off < 0) - goto out_unlock; + goto restart; area_found: + spin_unlock_irq(&pcpu_lock); + /* populate, map and clear the area */ if (pcpu_populate_chunk(chunk, off, size)) { + spin_lock_irq(&pcpu_lock); pcpu_free_area(chunk, off); - goto out_unlock; + goto fail_unlock; } - ptr = __addr_to_pcpu_ptr(chunk->vm->addr + off); -out_unlock: - mutex_unlock(&pcpu_mutex); - return ptr; + mutex_unlock(&pcpu_alloc_mutex); + + return __addr_to_pcpu_ptr(chunk->vm->addr + off); + +fail_unlock: + spin_unlock_irq(&pcpu_lock); +fail_unlock_mutex: + mutex_unlock(&pcpu_alloc_mutex); + return NULL; +} + +/** + * __alloc_percpu - allocate dynamic percpu area + * @size: size of area to allocate in bytes + * @align: alignment of area (max PAGE_SIZE) + * + * Allocate percpu area of @size bytes aligned at @align. Might + * sleep. Might trigger writeouts. + * + * CONTEXT: + * Does GFP_KERNEL allocation. + * + * RETURNS: + * Percpu pointer to the allocated area on success, NULL on failure. + */ +void *__alloc_percpu(size_t size, size_t align) +{ + return pcpu_alloc(size, align, false); } EXPORT_SYMBOL_GPL(__alloc_percpu); -static void pcpu_kill_chunk(struct pcpu_chunk *chunk) +/** + * __alloc_reserved_percpu - allocate reserved percpu area + * @size: size of area to allocate in bytes + * @align: alignment of area (max PAGE_SIZE) + * + * Allocate percpu area of @size bytes aligned at @align from reserved + * percpu area if arch has set it up; otherwise, allocation is served + * from the same dynamic area. Might sleep. Might trigger writeouts. + * + * CONTEXT: + * Does GFP_KERNEL allocation. + * + * RETURNS: + * Percpu pointer to the allocated area on success, NULL on failure. + */ +void *__alloc_reserved_percpu(size_t size, size_t align) +{ + return pcpu_alloc(size, align, true); +} + +/** + * pcpu_reclaim - reclaim fully free chunks, workqueue function + * @work: unused + * + * Reclaim all fully free chunks except for the first one. + * + * CONTEXT: + * workqueue context. + */ +static void pcpu_reclaim(struct work_struct *work) { - WARN_ON(chunk->immutable); - pcpu_depopulate_chunk(chunk, 0, pcpu_unit_size, false); - list_del(&chunk->list); - rb_erase(&chunk->rb_node, &pcpu_addr_root); - free_pcpu_chunk(chunk); + LIST_HEAD(todo); + struct list_head *head = &pcpu_slot[pcpu_nr_slots - 1]; + struct pcpu_chunk *chunk, *next; + + mutex_lock(&pcpu_alloc_mutex); + spin_lock_irq(&pcpu_lock); + + list_for_each_entry_safe(chunk, next, head, list) { + WARN_ON(chunk->immutable); + + /* spare the first one */ + if (chunk == list_first_entry(head, struct pcpu_chunk, list)) + continue; + + rb_erase(&chunk->rb_node, &pcpu_addr_root); + list_move(&chunk->list, &todo); + } + + spin_unlock_irq(&pcpu_lock); + mutex_unlock(&pcpu_alloc_mutex); + + list_for_each_entry_safe(chunk, next, &todo, list) { + pcpu_depopulate_chunk(chunk, 0, pcpu_unit_size, false); + free_pcpu_chunk(chunk); + } } /** * free_percpu - free percpu area * @ptr: pointer to area to free * - * Free percpu area @ptr. Might sleep. + * Free percpu area @ptr. + * + * CONTEXT: + * Can be called from atomic context. */ void free_percpu(void *ptr) { void *addr = __pcpu_ptr_to_addr(ptr); struct pcpu_chunk *chunk; + unsigned long flags; int off; if (!ptr) return; - mutex_lock(&pcpu_mutex); + spin_lock_irqsave(&pcpu_lock, flags); chunk = pcpu_chunk_addr_search(addr); off = addr - chunk->vm->addr; pcpu_free_area(chunk, off); - /* the chunk became fully free, kill one if there are other free ones */ + /* if there are more than one fully free chunks, wake up grim reaper */ if (chunk->free_size == pcpu_unit_size) { struct pcpu_chunk *pos; - list_for_each_entry(pos, - &pcpu_slot[pcpu_chunk_slot(chunk)], list) + list_for_each_entry(pos, &pcpu_slot[pcpu_nr_slots - 1], list) if (pos != chunk) { - pcpu_kill_chunk(pos); + schedule_work(&pcpu_reclaim_work); break; } } - mutex_unlock(&pcpu_mutex); + spin_unlock_irqrestore(&pcpu_lock, flags); } EXPORT_SYMBOL_GPL(free_percpu); @@ -830,8 +1012,9 @@ EXPORT_SYMBOL_GPL(free_percpu); * pcpu_setup_first_chunk - initialize the first percpu chunk * @get_page_fn: callback to fetch page pointer * @static_size: the size of static percpu area in bytes - * @unit_size: unit size in bytes, must be multiple of PAGE_SIZE, 0 for auto - * @free_size: free size in bytes, 0 for auto + * @reserved_size: the size of reserved percpu area in bytes + * @unit_size: unit size in bytes, must be multiple of PAGE_SIZE, -1 for auto + * @dyn_size: free size for dynamic allocation in bytes, -1 for auto * @base_addr: mapped address, NULL for auto * @populate_pte_fn: callback to allocate pagetable, NULL if unnecessary * @@ -848,13 +1031,22 @@ EXPORT_SYMBOL_GPL(free_percpu); * indicates end of pages for the cpu. Note that @get_page_fn() must * return the same number of pages for all cpus. * - * @unit_size, if non-zero, determines unit size and must be aligned - * to PAGE_SIZE and equal to or larger than @static_size + @free_size. + * @reserved_size, if non-zero, specifies the amount of bytes to + * reserve after the static area in the first chunk. This reserves + * the first chunk such that it's available only through reserved + * percpu allocation. This is primarily used to serve module percpu + * static areas on architectures where the addressing model has + * limited offset range for symbol relocations to guarantee module + * percpu symbols fall inside the relocatable range. * - * @free_size determines the number of free bytes after the static - * area in the first chunk. If zero, whatever left is available. - * Specifying non-zero value make percpu leave the area after - * @static_size + @free_size alone. + * @unit_size, if non-negative, specifies unit size and must be + * aligned to PAGE_SIZE and equal to or larger than @static_size + + * @reserved_size + @dyn_size. + * + * @dyn_size, if non-negative, limits the number of bytes available + * for dynamic allocation in the first chunk. Specifying non-negative + * value make percpu leave alone the area beyond @static_size + + * @reserved_size + @dyn_size. * * Non-null @base_addr means that the caller already allocated virtual * region for the first chunk and mapped it. percpu must not mess @@ -864,41 +1056,58 @@ EXPORT_SYMBOL_GPL(free_percpu); * @populate_pte_fn is used to populate the pagetable. NULL means the * caller already populated the pagetable. * + * If the first chunk ends up with both reserved and dynamic areas, it + * is served by two chunks - one to serve the core static and reserved + * areas and the other for the dynamic area. They share the same vm + * and page map but uses different area allocation map to stay away + * from each other. The latter chunk is circulated in the chunk slots + * and available for dynamic allocation like any other chunks. + * * RETURNS: * The determined pcpu_unit_size which can be used to initialize * percpu access. */ size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, - size_t static_size, size_t unit_size, - size_t free_size, void *base_addr, + size_t static_size, size_t reserved_size, + ssize_t unit_size, ssize_t dyn_size, + void *base_addr, pcpu_populate_pte_fn_t populate_pte_fn) { - static struct vm_struct static_vm; - struct pcpu_chunk *static_chunk; + static struct vm_struct first_vm; + static int smap[2], dmap[2]; + struct pcpu_chunk *schunk, *dchunk = NULL; unsigned int cpu; int nr_pages; int err, i; /* santiy checks */ + BUILD_BUG_ON(ARRAY_SIZE(smap) >= PCPU_DFL_MAP_ALLOC || + ARRAY_SIZE(dmap) >= PCPU_DFL_MAP_ALLOC); BUG_ON(!static_size); - BUG_ON(!unit_size && free_size); - BUG_ON(unit_size && unit_size < static_size + free_size); - BUG_ON(unit_size & ~PAGE_MASK); - BUG_ON(base_addr && !unit_size); + if (unit_size >= 0) { + BUG_ON(unit_size < static_size + reserved_size + + (dyn_size >= 0 ? dyn_size : 0)); + BUG_ON(unit_size & ~PAGE_MASK); + } else { + BUG_ON(dyn_size >= 0); + BUG_ON(base_addr); + } BUG_ON(base_addr && populate_pte_fn); - if (unit_size) + if (unit_size >= 0) pcpu_unit_pages = unit_size >> PAGE_SHIFT; else pcpu_unit_pages = max_t(int, PCPU_MIN_UNIT_SIZE >> PAGE_SHIFT, - PFN_UP(static_size)); + PFN_UP(static_size + reserved_size)); - pcpu_static_size = static_size; pcpu_unit_size = pcpu_unit_pages << PAGE_SHIFT; pcpu_chunk_size = num_possible_cpus() * pcpu_unit_size; pcpu_chunk_struct_size = sizeof(struct pcpu_chunk) + num_possible_cpus() * pcpu_unit_pages * sizeof(struct page *); + if (dyn_size < 0) + dyn_size = pcpu_unit_size - static_size - reserved_size; + /* * Allocate chunk slots. The additional last slot is for * empty chunks. @@ -908,33 +1117,66 @@ size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, for (i = 0; i < pcpu_nr_slots; i++) INIT_LIST_HEAD(&pcpu_slot[i]); - /* init static_chunk */ - static_chunk = alloc_bootmem(pcpu_chunk_struct_size); - INIT_LIST_HEAD(&static_chunk->list); - static_chunk->vm = &static_vm; - - if (free_size) - static_chunk->free_size = free_size; - else - static_chunk->free_size = pcpu_unit_size - pcpu_static_size; - - static_chunk->contig_hint = static_chunk->free_size; + /* + * Initialize static chunk. If reserved_size is zero, the + * static chunk covers static area + dynamic allocation area + * in the first chunk. If reserved_size is not zero, it + * covers static area + reserved area (mostly used for module + * static percpu allocation). + */ + schunk = alloc_bootmem(pcpu_chunk_struct_size); + INIT_LIST_HEAD(&schunk->list); + schunk->vm = &first_vm; + schunk->map = smap; + schunk->map_alloc = ARRAY_SIZE(smap); + schunk->page = schunk->page_ar; + + if (reserved_size) { + schunk->free_size = reserved_size; + pcpu_reserved_chunk = schunk; /* not for dynamic alloc */ + } else { + schunk->free_size = dyn_size; + dyn_size = 0; /* dynamic area covered */ + } + schunk->contig_hint = schunk->free_size; + + schunk->map[schunk->map_used++] = -static_size; + if (schunk->free_size) + schunk->map[schunk->map_used++] = schunk->free_size; + + pcpu_reserved_chunk_limit = static_size + schunk->free_size; + + /* init dynamic chunk if necessary */ + if (dyn_size) { + dchunk = alloc_bootmem(sizeof(struct pcpu_chunk)); + INIT_LIST_HEAD(&dchunk->list); + dchunk->vm = &first_vm; + dchunk->map = dmap; + dchunk->map_alloc = ARRAY_SIZE(dmap); + dchunk->page = schunk->page_ar; /* share page map with schunk */ + + dchunk->contig_hint = dchunk->free_size = dyn_size; + dchunk->map[dchunk->map_used++] = -pcpu_reserved_chunk_limit; + dchunk->map[dchunk->map_used++] = dchunk->free_size; + } /* allocate vm address */ - static_vm.flags = VM_ALLOC; - static_vm.size = pcpu_chunk_size; + first_vm.flags = VM_ALLOC; + first_vm.size = pcpu_chunk_size; if (!base_addr) - vm_area_register_early(&static_vm, PAGE_SIZE); + vm_area_register_early(&first_vm, PAGE_SIZE); else { /* * Pages already mapped. No need to remap into - * vmalloc area. In this case the static chunk can't - * be mapped or unmapped by percpu and is marked + * vmalloc area. In this case the first chunks can't + * be mapped or unmapped by percpu and are marked * immutable. */ - static_vm.addr = base_addr; - static_chunk->immutable = true; + first_vm.addr = base_addr; + schunk->immutable = true; + if (dchunk) + dchunk->immutable = true; } /* assign pages */ @@ -945,10 +1187,10 @@ size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, if (!page) break; - *pcpu_chunk_pagep(static_chunk, cpu, i) = page; + *pcpu_chunk_pagep(schunk, cpu, i) = page; } - BUG_ON(i < PFN_UP(pcpu_static_size)); + BUG_ON(i < PFN_UP(static_size)); if (nr_pages < 0) nr_pages = i; @@ -960,20 +1202,25 @@ size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, if (populate_pte_fn) { for_each_possible_cpu(cpu) for (i = 0; i < nr_pages; i++) - populate_pte_fn(pcpu_chunk_addr(static_chunk, + populate_pte_fn(pcpu_chunk_addr(schunk, cpu, i)); - err = pcpu_map(static_chunk, 0, nr_pages); + err = pcpu_map(schunk, 0, nr_pages); if (err) panic("failed to setup static percpu area, err=%d\n", err); } - /* link static_chunk in */ - pcpu_chunk_relocate(static_chunk, -1); - pcpu_chunk_addr_insert(static_chunk); + /* link the first chunk in */ + if (!dchunk) { + pcpu_chunk_relocate(schunk, -1); + pcpu_chunk_addr_insert(schunk); + } else { + pcpu_chunk_relocate(dchunk, -1); + pcpu_chunk_addr_insert(dchunk); + } /* we're done */ - pcpu_base_addr = (void *)pcpu_chunk_addr(static_chunk, 0, 0); + pcpu_base_addr = (void *)pcpu_chunk_addr(schunk, 0, 0); return pcpu_unit_size; } |