diff options
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r-- | arch/arc/kernel/devtree.c | 24 | ||||
-rw-r--r-- | arch/arc/kernel/entry.S | 14 | ||||
-rw-r--r-- | arch/arc/kernel/process.c | 23 | ||||
-rw-r--r-- | arch/arc/kernel/setup.c | 7 | ||||
-rw-r--r-- | arch/arc/kernel/signal.c | 2 | ||||
-rw-r--r-- | arch/arc/kernel/smp.c | 2 | ||||
-rw-r--r-- | arch/arc/kernel/stacktrace.c | 21 | ||||
-rw-r--r-- | arch/arc/kernel/unaligned.c | 2 |
8 files changed, 60 insertions, 35 deletions
diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c index fffdb5e41b20..e32b54abff51 100644 --- a/arch/arc/kernel/devtree.c +++ b/arch/arc/kernel/devtree.c @@ -17,6 +17,28 @@ #include <asm/clk.h> #include <asm/mach_desc.h> +#ifdef CONFIG_SERIAL_EARLYCON + +static unsigned int __initdata arc_base_baud; + +unsigned int __init arc_early_base_baud(void) +{ + return arc_base_baud/16; +} + +static void __init arc_set_early_base_baud(unsigned long dt_root) +{ + unsigned int core_clk = arc_get_core_freq(); + + if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x")) + arc_base_baud = core_clk/3; + else + arc_base_baud = core_clk; +} +#else +#define arc_set_early_base_baud(dt_root) +#endif + static const void * __init arch_get_next_mach(const char *const **match) { static const struct machine_desc *mdesc = __arch_info_begin; @@ -56,5 +78,7 @@ const struct machine_desc * __init setup_machine_fdt(void *dt) if (clk) arc_set_core_freq(of_read_ulong(clk, len/4)); + arc_set_early_base_baud(dt_root); + return mdesc; } diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index 83a046a7cd06..d868289c5a26 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -736,16 +736,20 @@ ENTRY(ret_from_fork) ; put last task in scheduler queue bl @schedule_tail - ; If kernel thread, jump to its entry-point ld r9, [sp, PT_status32] brne r9, 0, 1f - jl.d [r14] - mov r0, r13 ; arg to payload + jl.d [r14] ; kernel thread entry point + mov r0, r13 ; (see PF_KTHREAD block in copy_thread) 1: - ; special case of kernel_thread entry point returning back due to - ; kernel_execve() - pretend return from syscall to ret to userland + ; Return to user space + ; 1. Any forked task (Reach here via BRne above) + ; 2. First ever init task (Reach here via return from JL above) + ; This is the historic "kernel_execve" use-case, to return to init + ; user mode, in a round about way since that is always done from + ; a kernel thread which is executed via JL above but always returns + ; out whenever kernel_execve (now inline do_fork()) is involved b ret_from_exception END(ret_from_fork) diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c index fdd89715d2d3..98c00a2d4dd9 100644 --- a/arch/arc/kernel/process.c +++ b/arch/arc/kernel/process.c @@ -192,29 +192,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) return 0; } -/* - * API: expected by schedular Code: If thread is sleeping where is that. - * What is this good for? it will be always the scheduler or ret_from_fork. - * So we hard code that anyways. - */ -unsigned long thread_saved_pc(struct task_struct *t) -{ - struct pt_regs *regs = task_pt_regs(t); - unsigned long blink = 0; - - /* - * If the thread being queried for in not itself calling this, then it - * implies it is not executing, which in turn implies it is sleeping, - * which in turn implies it got switched OUT by the schedular. - * In that case, it's kernel mode blink can reliably retrieved as per - * the picture above (right above pt_regs). - */ - if (t != current && t->state != TASK_RUNNING) - blink = *((unsigned int *)regs - 1); - - return blink; -} - int elf_check_arch(const struct elf32_hdr *x) { unsigned int eflags; diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 252bf603db9c..900f68a70088 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -412,6 +412,11 @@ static int show_cpuinfo(struct seq_file *m, void *v) char *str; int cpu_id = ptr_to_cpu(v); + if (!cpu_online(cpu_id)) { + seq_printf(m, "processor [%d]\t: Offline\n", cpu_id); + goto done; + } + str = (char *)__get_free_page(GFP_TEMPORARY); if (!str) goto done; @@ -429,7 +434,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) free_page((unsigned long)str); done: - seq_printf(m, "\n\n"); + seq_printf(m, "\n"); return 0; } diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c index cb3142a2d40b..114234e83caa 100644 --- a/arch/arc/kernel/signal.c +++ b/arch/arc/kernel/signal.c @@ -104,7 +104,7 @@ SYSCALL_DEFINE0(rt_sigreturn) struct pt_regs *regs = current_pt_regs(); /* Always make any pending restarted system calls return -EINTR */ - current_thread_info()->restart_block.fn = do_no_restart_syscall; + current->restart_block.fn = do_no_restart_syscall; /* Since we stacked the signal on a word boundary, * then 'sp' should be word aligned here. If it's diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c index 20ebb602ea2f..6a400b1b0b62 100644 --- a/arch/arc/kernel/smp.c +++ b/arch/arc/kernel/smp.c @@ -221,7 +221,7 @@ static void ipi_send_msg_one(int cpu, enum ipi_msg_type msg) * and read back old value */ do { - new = old = *ipi_data_ptr; + new = old = ACCESS_ONCE(*ipi_data_ptr); new |= 1U << msg; } while (cmpxchg(ipi_data_ptr, old, new) != old); diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c index 9ce47cfe2303..92320d6f737c 100644 --- a/arch/arc/kernel/stacktrace.c +++ b/arch/arc/kernel/stacktrace.c @@ -43,6 +43,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs, struct unwind_frame_info *frame_info) { + /* + * synchronous unwinding (e.g. dump_stack) + * - uses current values of SP and friends + */ if (tsk == NULL && regs == NULL) { unsigned long fp, sp, blink, ret; frame_info->task = current; @@ -61,12 +65,17 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->regs.r63 = ret; frame_info->call_frame = 0; } else if (regs == NULL) { + /* + * Asynchronous unwinding of sleeping task + * - Gets SP etc from task's pt_regs (saved bottom of kernel + * mode stack of task) + */ frame_info->task = tsk; - frame_info->regs.r27 = KSTK_FP(tsk); - frame_info->regs.r28 = KSTK_ESP(tsk); - frame_info->regs.r31 = KSTK_BLINK(tsk); + frame_info->regs.r27 = TSK_K_FP(tsk); + frame_info->regs.r28 = TSK_K_ESP(tsk); + frame_info->regs.r31 = TSK_K_BLINK(tsk); frame_info->regs.r63 = (unsigned int)__switch_to; /* In the prologue of __switch_to, first FP is saved on stack @@ -83,6 +92,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->call_frame = 0; } else { + /* + * Asynchronous unwinding of intr/exception + * - Just uses the pt_regs passed + */ frame_info->task = tsk; frame_info->regs.r27 = regs->fp; @@ -95,7 +108,7 @@ static void seed_unwind_frame_info(struct task_struct *tsk, #endif -static noinline unsigned int +notrace noinline unsigned int arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs, int (*consumer_fn) (unsigned int, void *), void *arg) { diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c index 7ff5b5c183bb..74db59b6f392 100644 --- a/arch/arc/kernel/unaligned.c +++ b/arch/arc/kernel/unaligned.c @@ -12,6 +12,7 @@ */ #include <linux/types.h> +#include <linux/perf_event.h> #include <linux/ptrace.h> #include <linux/uaccess.h> #include <asm/disasm.h> @@ -253,6 +254,7 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, } } + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address); return 0; fault: |