diff options
| -rw-r--r-- | arch/Kconfig | 4 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/init.c | 17 | ||||
| -rw-r--r-- | arch/x86/kernel/process.c | 2 | ||||
| -rw-r--r-- | fs/proc/kcore.c | 4 | ||||
| -rw-r--r-- | include/linux/sched.h | 6 | ||||
| -rw-r--r-- | kernel/fork.c | 11 |
7 files changed, 27 insertions, 18 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index bec6666a3cc4..8a8ea7110de8 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -221,6 +221,10 @@ config ARCH_TASK_STRUCT_ALLOCATOR config ARCH_THREAD_INFO_ALLOCATOR bool +# Select if arch wants to size task_struct dynamically via arch_task_struct_size: +config ARCH_WANTS_DYNAMIC_TASK_STRUCT + bool + config HAVE_REGS_AND_STACK_ACCESS_API bool help diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 3dbb7e7909ca..b3a1a5d77d92 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -41,6 +41,7 @@ config X86 select ARCH_USE_CMPXCHG_LOCKREF if X86_64 select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS + select ARCH_WANTS_DYNAMIC_TASK_STRUCT select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_IPC_PARSE_VERSION if X86_32 select ARCH_WANT_OPTIONAL_GPIOLIB diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index deacbfa6b33e..0b39173dd971 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -4,6 +4,8 @@ #include <asm/fpu/internal.h> #include <asm/tlbflush.h> +#include <linux/sched.h> + /* * Initialize the TS bit in CR0 according to the style of context-switches * we are using: @@ -136,16 +138,14 @@ static void __init fpu__init_system_generic(void) unsigned int xstate_size; EXPORT_SYMBOL_GPL(xstate_size); -#define CHECK_MEMBER_AT_END_OF(TYPE, MEMBER) \ - BUILD_BUG_ON((sizeof(TYPE) - \ - offsetof(TYPE, MEMBER) - \ - sizeof(((TYPE *)0)->MEMBER)) > \ - 0) \ +/* Enforce that 'MEMBER' is the last field of 'TYPE': */ +#define CHECK_MEMBER_AT_END_OF(TYPE, MEMBER) \ + BUILD_BUG_ON(sizeof(TYPE) != offsetofend(TYPE, MEMBER)) /* - * We append the 'struct fpu' to the task_struct. + * We append the 'struct fpu' to the task_struct: */ -int __weak arch_task_struct_size(void) +static void __init fpu__init_task_struct_size(void) { int task_size = sizeof(struct task_struct); @@ -172,7 +172,7 @@ int __weak arch_task_struct_size(void) CHECK_MEMBER_AT_END_OF(struct thread_struct, fpu); CHECK_MEMBER_AT_END_OF(struct task_struct, thread); - return task_size; + arch_task_struct_size = task_size; } /* @@ -326,6 +326,7 @@ void __init fpu__init_system(struct cpuinfo_x86 *c) fpu__init_system_generic(); fpu__init_system_xstate_size_legacy(); fpu__init_system_xstate(); + fpu__init_task_struct_size(); fpu__init_system_ctx_switch(); } diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 975420eac105..397688beed4b 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -81,7 +81,7 @@ EXPORT_SYMBOL_GPL(idle_notifier_unregister); */ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) { - memcpy(dst, src, arch_task_struct_size()); + memcpy(dst, src, arch_task_struct_size); return fpu__copy(&dst->thread.fpu, &src->thread.fpu); } diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index a0fe99485687..92e6726f6e37 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -92,7 +92,7 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen) roundup(sizeof(CORE_STR), 4)) + roundup(sizeof(struct elf_prstatus), 4) + roundup(sizeof(struct elf_prpsinfo), 4) + - roundup(arch_task_struct_size(), 4); + roundup(arch_task_struct_size, 4); *elf_buflen = PAGE_ALIGN(*elf_buflen); return size + *elf_buflen; } @@ -415,7 +415,7 @@ static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff) /* set up the task structure */ notes[2].name = CORE_STR; notes[2].type = NT_TASKSTRUCT; - notes[2].datasz = arch_task_struct_size(); + notes[2].datasz = arch_task_struct_size; notes[2].data = current; nhdr->p_filesz += notesize(¬es[2]); diff --git a/include/linux/sched.h b/include/linux/sched.h index e43a41d892b6..04b5ada460b4 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1786,7 +1786,11 @@ struct task_struct { */ }; -extern int arch_task_struct_size(void); +#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT +extern int arch_task_struct_size __read_mostly; +#else +# define arch_task_struct_size (sizeof(struct task_struct)) +#endif /* Future-safe accessor for struct task_struct's cpus_allowed. */ #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) diff --git a/kernel/fork.c b/kernel/fork.c index 431b67a6098c..dbd9b8d7b7cc 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -287,21 +287,20 @@ static void set_max_threads(unsigned int max_threads_suggested) max_threads = clamp_t(u64, threads, MIN_THREADS, MAX_THREADS); } -int __weak arch_task_struct_size(void) -{ - return sizeof(struct task_struct); -} +#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT +/* Initialized by the architecture: */ +int arch_task_struct_size __read_mostly; +#endif void __init fork_init(void) { - int task_struct_size = arch_task_struct_size(); #ifndef CONFIG_ARCH_TASK_STRUCT_ALLOCATOR #ifndef ARCH_MIN_TASKALIGN #define ARCH_MIN_TASKALIGN L1_CACHE_BYTES #endif /* create a slab on which task_structs can be allocated */ task_struct_cachep = - kmem_cache_create("task_struct", task_struct_size, + kmem_cache_create("task_struct", arch_task_struct_size, ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL); #endif |