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https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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e317603694
UP __alloc_percpu() triggered WARN_ON_ONCE() if the requested alignment is larger than that of unsigned long long, which is too small for all the cacheline aligned allocations. Bump it up to SMP_CACHE_BYTES which kmalloc allocations generally guarantee. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Ingo Molnar <mingo@elte.hu>
174 lines
4.8 KiB
C
174 lines
4.8 KiB
C
#ifndef __LINUX_PERCPU_H
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#define __LINUX_PERCPU_H
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#include <linux/preempt.h>
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#include <linux/slab.h> /* For kmalloc() */
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#include <linux/smp.h>
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#include <linux/cpumask.h>
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#include <asm/percpu.h>
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#ifndef PER_CPU_BASE_SECTION
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#ifdef CONFIG_SMP
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#define PER_CPU_BASE_SECTION ".data.percpu"
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#else
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#define PER_CPU_BASE_SECTION ".data"
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#endif
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#endif
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#ifdef CONFIG_SMP
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#ifdef MODULE
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#define PER_CPU_SHARED_ALIGNED_SECTION ""
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#else
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#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
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#endif
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#define PER_CPU_FIRST_SECTION ".first"
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#else
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#define PER_CPU_SHARED_ALIGNED_SECTION ""
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#define PER_CPU_FIRST_SECTION ""
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#endif
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#define DEFINE_PER_CPU_SECTION(type, name, section) \
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__attribute__((__section__(PER_CPU_BASE_SECTION section))) \
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PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
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#define DEFINE_PER_CPU(type, name) \
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DEFINE_PER_CPU_SECTION(type, name, "")
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#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
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DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
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____cacheline_aligned_in_smp
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#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
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DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
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#define DEFINE_PER_CPU_FIRST(type, name) \
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DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
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#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
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#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
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/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
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#ifndef PERCPU_ENOUGH_ROOM
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#ifdef CONFIG_MODULES
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#define PERCPU_MODULE_RESERVE 8192
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#else
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#define PERCPU_MODULE_RESERVE 0
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#endif
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#define PERCPU_ENOUGH_ROOM \
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(__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
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#endif /* PERCPU_ENOUGH_ROOM */
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/*
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* Must be an lvalue. Since @var must be a simple identifier,
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* we force a syntax error here if it isn't.
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*/
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#define get_cpu_var(var) (*({ \
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extern int simple_identifier_##var(void); \
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preempt_disable(); \
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&__get_cpu_var(var); }))
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#define put_cpu_var(var) preempt_enable()
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#ifdef CONFIG_SMP
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#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
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/* minimum unit size, also is the maximum supported allocation size */
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#define PCPU_MIN_UNIT_SIZE (16UL << PAGE_SHIFT)
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/*
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* PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
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* back on the first chunk if arch is manually allocating and mapping
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* it for faster access (as a part of large page mapping for example).
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* Note that dynamic percpu allocator covers both static and dynamic
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* areas, so these values are bigger than PERCPU_MODULE_RESERVE.
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*
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* On typical configuration with modules, the following values leave
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* about 8k of free space on the first chunk after boot on both x86_32
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* and 64 when module support is enabled. When module support is
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* disabled, it's much tighter.
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*/
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#ifndef PERCPU_DYNAMIC_RESERVE
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# if BITS_PER_LONG > 32
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# ifdef CONFIG_MODULES
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# define PERCPU_DYNAMIC_RESERVE (6 << PAGE_SHIFT)
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# else
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# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT)
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# endif
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# else
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# ifdef CONFIG_MODULES
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# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT)
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# else
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# define PERCPU_DYNAMIC_RESERVE (2 << PAGE_SHIFT)
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# endif
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# endif
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#endif /* PERCPU_DYNAMIC_RESERVE */
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extern void *pcpu_base_addr;
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typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno);
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typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr);
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extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn,
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size_t static_size, size_t unit_size,
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size_t free_size, void *base_addr,
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pcpu_populate_pte_fn_t populate_pte_fn);
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/*
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* Use this to get to a cpu's version of the per-cpu object
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* dynamically allocated. Non-atomic access to the current CPU's
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* version should probably be combined with get_cpu()/put_cpu().
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*/
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#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
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#else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
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struct percpu_data {
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void *ptrs[1];
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};
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#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
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#define per_cpu_ptr(ptr, cpu) \
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({ \
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struct percpu_data *__p = __percpu_disguise(ptr); \
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(__typeof__(ptr))__p->ptrs[(cpu)]; \
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})
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#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
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extern void *__alloc_percpu(size_t size, size_t align);
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extern void free_percpu(void *__pdata);
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#else /* CONFIG_SMP */
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#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
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static inline void *__alloc_percpu(size_t size, size_t align)
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{
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/*
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* Can't easily make larger alignment work with kmalloc. WARN
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* on it. Larger alignment should only be used for module
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* percpu sections on SMP for which this path isn't used.
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*/
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WARN_ON_ONCE(align > SMP_CACHE_BYTES);
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return kzalloc(size, GFP_KERNEL);
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}
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static inline void free_percpu(void *p)
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{
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kfree(p);
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}
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#endif /* CONFIG_SMP */
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#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \
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__alignof__(type))
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#endif /* __LINUX_PERCPU_H */
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