From 09a072947791088b88ae15111cf68fc5aaaf758d Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 9 Nov 2009 16:27:40 +0900 Subject: sh: hw-breakpoints: Add preliminary support for SH-4A UBC. This adds preliminary support for the SH-4A UBC to the hw-breakpoints API. Presently only a single channel is implemented, and the ptrace interface still needs to be converted. This is the first step to cleaning up the long-standing UBC mess, making the UBC more generally accessible, and finally making it SMP safe. An additional abstraction will be layered on top of this as with the perf events code to permit the various CPU families to wire up support for their own specific UBCs, as many variations exist. Signed-off-by: Paul Mundt --- arch/sh/kernel/ptrace_32.c | 19 ------------------- 1 file changed, 19 deletions(-) (limited to 'arch/sh/kernel/ptrace_32.c') diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c index 9be35f34809..bdb10446cba 100644 --- a/arch/sh/kernel/ptrace_32.c +++ b/arch/sh/kernel/ptrace_32.c @@ -65,31 +65,12 @@ static inline int put_stack_long(struct task_struct *task, int offset, void user_enable_single_step(struct task_struct *child) { - /* Next scheduling will set up UBC */ - if (child->thread.ubc_pc == 0) - ubc_usercnt += 1; - - child->thread.ubc_pc = get_stack_long(child, - offsetof(struct pt_regs, pc)); - set_tsk_thread_flag(child, TIF_SINGLESTEP); } void user_disable_single_step(struct task_struct *child) { clear_tsk_thread_flag(child, TIF_SINGLESTEP); - - /* - * Ensure the UBC is not programmed at the next context switch. - * - * Normally this is not needed but there are sequences such as - * singlestep, signal delivery, and continue that leave the - * ubc_pc non-zero leading to spurious SIGTRAPs. - */ - if (child->thread.ubc_pc != 0) { - ubc_usercnt -= 1; - child->thread.ubc_pc = 0; - } } /* -- cgit v1.2.3-18-g5258 From 34d0b5af50a063cded842716633501b38ff815fb Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 28 Dec 2009 17:53:47 +0900 Subject: sh: Convert ptrace to hw_breakpoint API. This is the initial step for converting singlestep handling via ptrace over to hw_breakpoints. Signed-off-by: Paul Mundt --- arch/sh/kernel/ptrace_32.c | 53 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) (limited to 'arch/sh/kernel/ptrace_32.c') diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c index bdb10446cba..8e094c4c7bb 100644 --- a/arch/sh/kernel/ptrace_32.c +++ b/arch/sh/kernel/ptrace_32.c @@ -2,7 +2,7 @@ * SuperH process tracing * * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka - * Copyright (C) 2002 - 2008 Paul Mundt + * Copyright (C) 2002 - 2009 Paul Mundt * * Audit support by Yuichi Nakamura * @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -63,9 +64,59 @@ static inline int put_stack_long(struct task_struct *task, int offset, return 0; } +void ptrace_triggered(struct perf_event *bp, int nmi, + struct perf_sample_data *data, struct pt_regs *regs) +{ + struct perf_event_attr attr; + + /* + * Disable the breakpoint request here since ptrace has defined a + * one-shot behaviour for breakpoint exceptions. + */ + attr = bp->attr; + attr.disabled = true; + modify_user_hw_breakpoint(bp, &attr); +} + +static int set_single_step(struct task_struct *tsk, unsigned long addr) +{ + struct thread_struct *thread = &tsk->thread; + struct perf_event *bp; + struct perf_event_attr attr; + + bp = thread->ptrace_bps[0]; + if (!bp) { + hw_breakpoint_init(&attr); + + attr.bp_addr = addr; + attr.bp_len = HW_BREAKPOINT_LEN_2; + attr.bp_type = HW_BREAKPOINT_R; + + bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk); + if (IS_ERR(bp)) + return PTR_ERR(bp); + + thread->ptrace_bps[0] = bp; + } else { + int err; + + attr = bp->attr; + attr.bp_addr = addr; + err = modify_user_hw_breakpoint(bp, &attr); + if (unlikely(err)) + return err; + } + + return 0; +} + void user_enable_single_step(struct task_struct *child) { + unsigned long pc = get_stack_long(child, offsetof(struct pt_regs, pc)); + set_tsk_thread_flag(child, TIF_SINGLESTEP); + + set_single_step(child, pc); } void user_disable_single_step(struct task_struct *child) -- cgit v1.2.3-18-g5258 From 0ea820cf9bf58f735ed40ec67947159c4f170012 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Wed, 13 Jan 2010 12:51:40 +0900 Subject: sh: Move over to dynamically allocated FPU context. This follows the x86 xstate changes and implements a task_xstate slab cache that is dynamically sized to match one of hard FP/soft FP/FPU-less. This also tidies up and consolidates some of the SH-2A/SH-4 FPU fragmentation. Now fpu state restorers are commonly defined, with the init_fpu()/fpu_init() mess reworked to follow the x86 convention. The fpu_init() register initialization has been replaced by xstate setup followed by writing out to hardware via the standard restore path. As init_fpu() now performs a slab allocation a secondary lighterweight restorer is also introduced for the context switch. In the future the DSP state will be rolled in here, too. More work remains for math emulation and the SH-5 FPU, which presently uses its own special (UP-only) interfaces. Signed-off-by: Paul Mundt --- arch/sh/kernel/ptrace_32.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'arch/sh/kernel/ptrace_32.c') diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c index 9be35f34809..be9b5dcb402 100644 --- a/arch/sh/kernel/ptrace_32.c +++ b/arch/sh/kernel/ptrace_32.c @@ -163,10 +163,10 @@ int fpregs_get(struct task_struct *target, if ((boot_cpu_data.flags & CPU_HAS_FPU)) return user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.fpu.hard, 0, -1); + &target->thread.xstate->hardfpu, 0, -1); return user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.fpu.soft, 0, -1); + &target->thread.xstate->softfpu, 0, -1); } static int fpregs_set(struct task_struct *target, @@ -184,10 +184,10 @@ static int fpregs_set(struct task_struct *target, if ((boot_cpu_data.flags & CPU_HAS_FPU)) return user_regset_copyin(&pos, &count, &kbuf, &ubuf, - &target->thread.fpu.hard, 0, -1); + &target->thread.xstate->hardfpu, 0, -1); return user_regset_copyin(&pos, &count, &kbuf, &ubuf, - &target->thread.fpu.soft, 0, -1); + &target->thread.xstate->softfpu, 0, -1); } static int fpregs_active(struct task_struct *target, @@ -333,7 +333,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) else tmp = 0; } else - tmp = ((long *)&child->thread.fpu) + tmp = ((long *)child->thread.xstate) [(addr - (long)&dummy->fpu) >> 2]; } else if (addr == (long) &dummy->u_fpvalid) tmp = !!tsk_used_math(child); @@ -362,7 +362,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) else if (addr >= (long) &dummy->fpu && addr < (long) &dummy->u_fpvalid) { set_stopped_child_used_math(child); - ((long *)&child->thread.fpu) + ((long *)child->thread.xstate) [(addr - (long)&dummy->fpu) >> 2] = data; ret = 0; } else if (addr == (long) &dummy->u_fpvalid) { -- cgit v1.2.3-18-g5258