From 864232fa1a2f8dfe003438ef0851a56722740f3e Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 3 Sep 2010 10:42:55 +0100 Subject: ARM: 6357/1: hw-breakpoint: add new ptrace requests for hw-breakpoint interaction For debuggers to take advantage of the hw-breakpoint framework in the kernel, it is necessary to expose the API calls via a ptrace interface. This patch exposes the hardware breakpoints framework as a collection of virtual registers, accesible using PTRACE_SETHBPREGS and PTRACE_GETHBPREGS requests. The breakpoints are stored in the debug_info struct of the running thread. Cc: Frederic Weisbecker Cc: S. Karthikeyan Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/process.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 401e38be1f78..974af1c3eb1d 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -317,6 +318,8 @@ void flush_thread(void) struct thread_info *thread = current_thread_info(); struct task_struct *tsk = current; + flush_ptrace_hw_breakpoint(tsk); + memset(thread->used_cp, 0, sizeof(thread->used_cp)); memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); memset(&thread->fpstate, 0, sizeof(union fp_state)); @@ -345,6 +348,8 @@ copy_thread(unsigned long clone_flags, unsigned long stack_start, thread->cpu_context.sp = (unsigned long)childregs; thread->cpu_context.pc = (unsigned long)ret_from_fork; + clear_ptrace_hw_breakpoint(p); + if (clone_flags & CLONE_SETTLS) thread->tp_value = regs->ARM_r3; -- cgit v1.2.3 From c7b0aff44a0740eedd31b759fd08d9e25672fa76 Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Fri, 1 Oct 2010 22:13:47 +0100 Subject: ARM: 6428/1: add cpu_idle_wait() to support CPUidle on SMP systems. In order for CPUidle to work on SMP systems, an implementation of cpu_idle_wait() is needed. This patch duplicates the x86 implementation of cpu_idle_wait() for ARM. Tested-by: Colin Cross Signed-off-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/Kconfig | 3 +++ arch/arm/include/asm/system.h | 2 ++ arch/arm/kernel/process.c | 19 +++++++++++++++++++ 3 files changed, 24 insertions(+) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 7562f884f2c5..94360e7a7abc 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -145,6 +145,9 @@ config ARCH_HAS_CPUFREQ and that the relevant menu configurations are displayed for it. +config ARCH_HAS_CPU_IDLE_WAIT + def_bool y + config GENERIC_HWEIGHT bool default y diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 8ba1ccf82a02..48e360c74327 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -325,6 +325,8 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size extern void disable_hlt(void); extern void enable_hlt(void); +void cpu_idle_wait(void); + #include #if __LINUX_ARM_ARCH__ < 6 diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 401e38be1f78..23def52d2d24 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -135,6 +135,25 @@ EXPORT_SYMBOL(pm_power_off); void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart; EXPORT_SYMBOL_GPL(arm_pm_restart); +static void do_nothing(void *unused) +{ +} + +/* + * cpu_idle_wait - Used to ensure that all the CPUs discard old value of + * pm_idle and update to new pm_idle value. Required while changing pm_idle + * handler on SMP systems. + * + * Caller must have changed pm_idle to the new value before the call. Old + * pm_idle value will not be used by any CPU after the return of this function. + */ +void cpu_idle_wait(void) +{ + smp_mb(); + /* kick all the CPUs so that they exit out of pm_idle */ + smp_call_function(do_nothing, NULL, 1); +} +EXPORT_SYMBOL_GPL(cpu_idle_wait); /* * This is our default idle handler. We need to disable -- cgit v1.2.3