From 6cb7bfebb145af5ea1d052512a2ae7ff07a47202 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Fri, 21 Oct 2005 15:45:50 +1000 Subject: [PATCH] powerpc: Merge thread_info.h Merge ppc32 and ppc64 versions of thread_info.h. They were pretty similar already, the chief changes are: - Instead of inline asm to implement current_thread_info(), which needs to be different for ppc32 and ppc64, we use C with an asm("r1") register variable. gcc turns it into the same asm as we used to have for both platforms. - We replace ppc32's 'local_flags' with the ppc64 'syscall_noerror' field. The noerror flag was in fact the only thing in the local_flags field anyway, so the ppc64 approach is simpler, and means we only need a load-immediate/store instead of load/mask/store when clearing the flag. - In readiness for 64k pages, when THREAD_SIZE will be less than a page, ppc64 used kmalloc() rather than get_free_pages() to allocate the kernel stack. With this patch we do the same for ppc32, since there's no strong reason not to. - For ppc64, we no longer export THREAD_SHIFT and THREAD_SIZE via asm-offsets, thread_info.h can now be safely included in asm, as on ppc32. Built and booted on G4 Powerbook (ARCH=ppc and ARCH=powerpc) and Power5 (ARCH=ppc64 and ARCH=powerpc). Signed-off-by: David Gibson Signed-off-by: Paul Mackerras --- include/asm-powerpc/thread_info.h | 135 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 include/asm-powerpc/thread_info.h (limited to 'include/asm-powerpc/thread_info.h') diff --git a/include/asm-powerpc/thread_info.h b/include/asm-powerpc/thread_info.h new file mode 100644 index 000000000000..0b4c24551c21 --- /dev/null +++ b/include/asm-powerpc/thread_info.h @@ -0,0 +1,135 @@ +/* thread_info.h: PowerPC low-level thread information + * adapted from the i386 version by Paul Mackerras + * + * Copyright (C) 2002 David Howells (dhowells@redhat.com) + * - Incorporating suggestions made by Linus Torvalds and Dave Miller + */ + +#ifndef _ASM_POWERPC_THREAD_INFO_H +#define _ASM_POWERPC_THREAD_INFO_H + +#ifdef __KERNEL__ + +/* We have 8k stacks on ppc32 and 16k on ppc64 */ + +#ifdef CONFIG_PPC64 +#define THREAD_SHIFT 14 +#else +#define THREAD_SHIFT 13 +#endif + +#define THREAD_SIZE (1 << THREAD_SHIFT) + +#ifndef __ASSEMBLY__ +#include +#include +#include +#include +#include + +/* + * low level task data. + */ +struct thread_info { + struct task_struct *task; /* main task structure */ + struct exec_domain *exec_domain; /* execution domain */ + int cpu; /* cpu we're on */ + int preempt_count; /* 0 => preemptable, + <0 => BUG */ + struct restart_block restart_block; + /* set by force_successful_syscall_return */ + unsigned char syscall_noerror; + /* low level flags - has atomic operations done on it */ + unsigned long flags ____cacheline_aligned_in_smp; +}; + +/* + * macros/functions for gaining access to the thread information structure + * + * preempt_count needs to be 1 initially, until the scheduler is functional. + */ +#define INIT_THREAD_INFO(tsk) \ +{ \ + .task = &tsk, \ + .exec_domain = &default_exec_domain, \ + .cpu = 0, \ + .preempt_count = 1, \ + .restart_block = { \ + .fn = do_no_restart_syscall, \ + }, \ + .flags = 0, \ +} + +#define init_thread_info (init_thread_union.thread_info) +#define init_stack (init_thread_union.stack) + +/* thread information allocation */ + +#ifdef CONFIG_DEBUG_STACK_USAGE +#define alloc_thread_info(tsk) \ + ({ \ + struct thread_info *ret; \ + \ + ret = kmalloc(THREAD_SIZE, GFP_KERNEL); \ + if (ret) \ + memset(ret, 0, THREAD_SIZE); \ + ret; \ + }) +#else +#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL) +#endif +#define free_thread_info(ti) kfree(ti) +#define get_thread_info(ti) get_task_struct((ti)->task) +#define put_thread_info(ti) put_task_struct((ti)->task) + +/* how to get the thread information struct from C */ +static inline struct thread_info *current_thread_info(void) +{ + register unsigned long sp asm("r1"); + + /* gcc4, at least, is smart enough to turn this into a single + * rlwinm for ppc32 and clrrdi for ppc64 */ + return (struct thread_info *)(sp & ~(THREAD_SIZE-1)); +} + +#endif /* __ASSEMBLY__ */ + +#define PREEMPT_ACTIVE 0x10000000 + +/* + * thread information flag bit numbers + */ +#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ +#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */ +#define TIF_SIGPENDING 2 /* signal pending */ +#define TIF_NEED_RESCHED 3 /* rescheduling necessary */ +#define TIF_POLLING_NRFLAG 4 /* true if poll_idle() is polling + TIF_NEED_RESCHED */ +#define TIF_32BIT 5 /* 32 bit binary */ +/* #define SPARE 6 */ +#define TIF_ABI_PENDING 7 /* 32/64 bit switch needed */ +#define TIF_SYSCALL_AUDIT 8 /* syscall auditing active */ +#define TIF_SINGLESTEP 9 /* singlestepping active */ +#define TIF_MEMDIE 10 +#define TIF_SECCOMP 11 /* secure computing */ + +/* as above, but as bit values */ +#define _TIF_SYSCALL_TRACE (1<