From 19390c4d03688b9940a1836f06b76ec622b9cd6f Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 10 Mar 2009 16:27:48 +0900 Subject: linker script: define __per_cpu_load on all SMP capable archs Impact: __per_cpu_load available on all SMP capable archs Percpu now requires three symbols to be defined - __per_cpu_load, __per_cpu_start and __per_cpu_end. There were three archs which didn't have it. Update them as follows. * powerpc: can use generic PERCPU() macro. Compile tested for powerpc32, compile/boot tested for powerpc64. * ia64: can use generic PERCPU_VADDR() macro. __phys_per_cpu_start is identical to __per_cpu_load. Compile tested and symbol table looks identical after the change except for the additional __per_cpu_load. * arm: added explicit __per_cpu_load definition. Currently uses unified .init output section so can't use the generic macro. Dunno whether the unified .init ouput section is required by arch peculiarity so I left it alone. Please break it up and use PERCPU() if possible. Signed-off-by: Tejun Heo Cc: Benjamin Herrenschmidt Cc: Pat Gefre Cc: Russell King --- arch/arm/kernel/vmlinux.lds.S | 1 + arch/ia64/kernel/vmlinux.lds.S | 12 ++---------- arch/powerpc/kernel/vmlinux.lds.S | 9 +-------- 3 files changed, 4 insertions(+), 18 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 85598f7..1602373 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -64,6 +64,7 @@ SECTIONS __initramfs_end = .; #endif . = ALIGN(4096); + __per_cpu_load = .; __per_cpu_start = .; *(.data.percpu.page_aligned) *(.data.percpu) diff --git a/arch/ia64/kernel/vmlinux.lds.S b/arch/ia64/kernel/vmlinux.lds.S index f45e4e5..3765efc 100644 --- a/arch/ia64/kernel/vmlinux.lds.S +++ b/arch/ia64/kernel/vmlinux.lds.S @@ -213,17 +213,9 @@ SECTIONS { *(.data.cacheline_aligned) } /* Per-cpu data: */ - percpu : { } :percpu . = ALIGN(PERCPU_PAGE_SIZE); - __phys_per_cpu_start = .; - .data.percpu PERCPU_ADDR : AT(__phys_per_cpu_start - LOAD_OFFSET) - { - __per_cpu_start = .; - *(.data.percpu.page_aligned) - *(.data.percpu) - *(.data.percpu.shared_aligned) - __per_cpu_end = .; - } + PERCPU_VADDR(PERCPU_ADDR, :percpu) + __phys_per_cpu_start = __per_cpu_load; . = __phys_per_cpu_start + PERCPU_PAGE_SIZE; /* ensure percpu data fits * into percpu page size */ diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 295ccc5..67f07f4 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -181,14 +181,7 @@ SECTIONS __initramfs_end = .; } #endif - . = ALIGN(PAGE_SIZE); - .data.percpu : AT(ADDR(.data.percpu) - LOAD_OFFSET) { - __per_cpu_start = .; - *(.data.percpu.page_aligned) - *(.data.percpu) - *(.data.percpu.shared_aligned) - __per_cpu_end = .; - } + PERCPU(PAGE_SIZE) . = ALIGN(8); .machine.desc : AT(ADDR(.machine.desc) - LOAD_OFFSET) { -- cgit v1.1 From e01009833e22dc87075d770554b34d797843ed23 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 10 Mar 2009 16:27:48 +0900 Subject: percpu: make x86 addr <-> pcpu ptr conversion macros generic Impact: generic addr <-> pcpu ptr conversion macros There's nothing arch specific about x86 __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr(). With proper __per_cpu_load and __per_cpu_start defined, they'll do the right thing regardless of actual layout. Move these macros from arch/x86/include/asm/percpu.h to mm/percpu.c and allow archs to override it as necessary. Signed-off-by: Tejun Heo --- arch/x86/include/asm/percpu.h | 8 -------- 1 file changed, 8 deletions(-) (limited to 'arch') diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h index 8f1d2fb..aee103b 100644 --- a/arch/x86/include/asm/percpu.h +++ b/arch/x86/include/asm/percpu.h @@ -43,14 +43,6 @@ #else /* ...!ASSEMBLY */ #include -#include - -#define __addr_to_pcpu_ptr(addr) \ - (void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr \ - + (unsigned long)__per_cpu_start) -#define __pcpu_ptr_to_addr(ptr) \ - (void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr \ - - (unsigned long)__per_cpu_start) #ifdef CONFIG_SMP #define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x -- cgit v1.1 From 6074d5b0a319fe8400ff079a3c289406ca024321 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 10 Mar 2009 16:27:48 +0900 Subject: percpu: more flexibility for @dyn_size of pcpu_setup_first_chunk() Impact: cleanup, more flexibility for first chunk init Non-negative @dyn_size used to be allowed iff @unit_size wasn't auto. This restriction stemmed from implementation detail and made things a bit less intuitive. This patch allows @dyn_size to be specified regardless of @unit_size and swaps the positions of @dyn_size and @unit_size so that the parameter order makes more sense (static, reserved and dyn sizes followed by enclosing unit_size). While at it, add @unit_size >= PCPU_MIN_UNIT_SIZE sanity check. Signed-off-by: Tejun Heo --- arch/x86/kernel/setup_percpu.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index efa615f..e41c51f 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -233,8 +233,8 @@ proceed: "%zu bytes\n", vm.addr, static_size); ret = pcpu_setup_first_chunk(pcpur_get_page, static_size, - PERCPU_FIRST_CHUNK_RESERVE, - PMD_SIZE, dyn_size, vm.addr, NULL); + PERCPU_FIRST_CHUNK_RESERVE, dyn_size, + PMD_SIZE, vm.addr, NULL); goto out_free_ar; enomem: @@ -315,9 +315,8 @@ static ssize_t __init setup_pcpu_embed(size_t static_size) pcpue_size >> PAGE_SHIFT, pcpue_ptr, static_size); return pcpu_setup_first_chunk(pcpue_get_page, static_size, - PERCPU_FIRST_CHUNK_RESERVE, - pcpue_unit_size, dyn_size, - pcpue_ptr, NULL); + PERCPU_FIRST_CHUNK_RESERVE, dyn_size, + pcpue_unit_size, pcpue_ptr, NULL); } /* @@ -375,8 +374,8 @@ static ssize_t __init setup_pcpu_4k(size_t static_size) pcpu4k_nr_static_pages, static_size); ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, - PERCPU_FIRST_CHUNK_RESERVE, -1, -1, NULL, - pcpu4k_populate_pte); + PERCPU_FIRST_CHUNK_RESERVE, -1, + -1, NULL, pcpu4k_populate_pte); goto out_free_ar; enomem: -- cgit v1.1 From 66c3a75772247c31feabefb724e082220a1ab060 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 10 Mar 2009 16:27:48 +0900 Subject: percpu: generalize embedding first chunk setup helper Impact: code reorganization Separate out embedding first chunk setup helper from x86 embedding first chunk allocator and put it in mm/percpu.c. This will be used by the default percpu first chunk allocator and possibly by other archs. Signed-off-by: Tejun Heo --- arch/x86/kernel/setup_percpu.c | 54 +++++------------------------------------- 1 file changed, 6 insertions(+), 48 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index e41c51f..400331b 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -257,31 +257,13 @@ 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 - * 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. + * module and dynamic reserves and embedded into linear physical + * mapping so that it can use PMD mapping without additional TLB + * pressure. */ -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) -{ - 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; + size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE; /* * If large page isn't supported, there's no benefit in doing @@ -291,32 +273,8 @@ static ssize_t __init setup_pcpu_embed(size_t static_size) if (!cpu_has_pse || pcpu_need_numa()) return -EINVAL; - /* allocate and copy */ - 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) { - 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_size >> PAGE_SHIFT, pcpue_ptr, static_size); - - return pcpu_setup_first_chunk(pcpue_get_page, static_size, - PERCPU_FIRST_CHUNK_RESERVE, dyn_size, - pcpue_unit_size, pcpue_ptr, NULL); + return pcpu_embed_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE, + reserve - PERCPU_FIRST_CHUNK_RESERVE, -1); } /* -- cgit v1.1