Merge branch 'android-2.6.36' into android-tegra-2.6.36

2 files changed, 59 insertions, 13 deletions

diff --git a/arch/arm/common/fiq_debugger.c b/arch/arm/common/fiq_debugger.c
index 1ba345d441d0..330053856c76 100644
--- a/arch/arm/common/fiq_debugger.c
+++ b/arch/arm/common/fiq_debugger.c
@@ -44,6 +44,10 @@
 #include "fiq_debugger_ringbuf.h"
 
 #define DEBUG_MAX 64
+#define MAX_UNHANDLED_FIQ_COUNT 1000000
+
+#define THREAD_INFO(sp) ((struct thread_info *) \
+		((unsigned long)(sp) & ~(THREAD_SIZE - 1)))
 
 struct fiq_debugger_state {
 	struct fiq_glue_handler handler;
@@ -70,6 +74,9 @@ struct fiq_debugger_state {
 	bool uart_clk_enabled;
 	struct wake_lock debugger_wake_lock;
 	bool console_enable;
+	int current_cpu;
+	atomic_t unhandled_fiq_count;
+	bool in_fiq;
 
 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 	struct console console;
@@ -388,8 +395,7 @@ void dump_stacktrace(struct fiq_debugger_state *state,
 		struct pt_regs * const regs, unsigned int depth, void *ssp)
 {
 	struct frame_tail *tail;
-	struct thread_info *real_thread_info = (struct thread_info *)
-				((unsigned long)ssp & ~(THREAD_SIZE - 1));
+	struct thread_info *real_thread_info = THREAD_INFO(ssp);
 	struct stacktrace_state sts;
 
 	sts.depth = depth;
@@ -449,6 +455,15 @@ static void debug_exec(struct fiq_debugger_state *state,
 	} else if (!strcmp(cmd, "console")) {
 		state->console_enable = true;
 		debug_printf(state, "console mode\n");
+	} else if (!strcmp(cmd, "cpu")) {
+		debug_printf(state, "cpu %d\n", state->current_cpu);
+	} else if (!strncmp(cmd, "cpu ", 4)) {
+		unsigned long cpu = 0;
+		if (strict_strtoul(cmd + 4, 10, &cpu) == 0)
+			state->current_cpu = cpu;
+		else
+			debug_printf(state, "invalid cpu\n");
+		debug_printf(state, "cpu %d\n", state->current_cpu);
 	} else {
 		if (state->debug_busy) {
 			debug_printf(state,
@@ -552,6 +567,26 @@ static void debug_fiq(struct fiq_glue_handler *h, void *regs, void *svc_sp)
 	int c;
 	static int last_c;
 	int count = 0;
+	unsigned int this_cpu = THREAD_INFO(svc_sp)->cpu;
+
+	if (this_cpu != state->current_cpu) {
+		if (state->in_fiq)
+			return;
+
+		if (atomic_inc_return(&state->unhandled_fiq_count) !=
+					MAX_UNHANDLED_FIQ_COUNT)
+			return;
+
+		debug_printf(state, "fiq_debugger: cpu %d not responding, "
+			"reverting to cpu %d\n", state->current_cpu,
+			this_cpu);
+
+		atomic_set(&state->unhandled_fiq_count, 0);
+		state->current_cpu = this_cpu;
+		return;
+	}
+
+	state->in_fiq = true;
 
 	while ((c = debug_getc(state)) != FIQ_DEBUGGER_NO_CHAR) {
 		count++;
@@ -606,6 +641,9 @@ static void debug_fiq(struct fiq_glue_handler *h, void *regs, void *svc_sp)
 	/* poke sleep timer if necessary */
 	if (state->debug_enable && !state->no_sleep)
 		debug_force_irq(state);
+
+	atomic_set(&state->unhandled_fiq_count, 0);
+	state->in_fiq = false;
 }
 
 static void debug_resume(struct fiq_glue_handler *h)
diff --git a/arch/arm/common/fiq_glue_setup.c b/arch/arm/common/fiq_glue_setup.c
index f878ea079b4d..4044c7db95c8 100644
--- a/arch/arm/common/fiq_glue_setup.c
+++ b/arch/arm/common/fiq_glue_setup.c
@@ -23,7 +23,7 @@ extern void fiq_glue_setup(void *func, void *data, void *sp);
 static struct fiq_handler fiq_debbuger_fiq_handler = {
 	.name = "fiq_glue",
 };
-static __percpu void *fiq_stack;
+DEFINE_PER_CPU(void *, fiq_stack);
 static struct fiq_glue_handler *current_handler;
 static DEFINE_MUTEX(fiq_glue_lock);
 
@@ -31,12 +31,13 @@ static void fiq_glue_setup_helper(void *info)
 {
 	struct fiq_glue_handler *handler = info;
 	fiq_glue_setup(handler->fiq, handler,
-		__this_cpu_ptr(fiq_stack) + THREAD_START_SP);
+		__get_cpu_var(fiq_stack) + THREAD_START_SP);
 }
 
 int fiq_glue_register_handler(struct fiq_glue_handler *handler)
 {
 	int ret;
+	int cpu;
 
 	if (!handler || !handler->fiq)
 		return -EINVAL;
@@ -47,10 +48,14 @@ int fiq_glue_register_handler(struct fiq_glue_handler *handler)
 		goto err_busy;
 	}
 
-	fiq_stack = __alloc_percpu(THREAD_SIZE, L1_CACHE_BYTES);
-	if (WARN_ON(!fiq_stack)) {
-		ret = -ENOMEM;
-		goto err_alloc_fiq_stack;
+	for_each_possible_cpu(cpu) {
+		void *stack;
+		stack = (void *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
+		if (WARN_ON(!stack)) {
+			ret = -ENOMEM;
+			goto err_alloc_fiq_stack;
+		}
+		per_cpu(fiq_stack, cpu) = stack;
 	}
 
 	ret = claim_fiq(&fiq_debbuger_fiq_handler);
@@ -61,12 +66,15 @@ int fiq_glue_register_handler(struct fiq_glue_handler *handler)
 	on_each_cpu(fiq_glue_setup_helper, handler, true);
 	set_fiq_handler(&fiq_glue, &fiq_glue_end - &fiq_glue);
 
+	mutex_unlock(&fiq_glue_lock);
+	return 0;
+
 err_claim_fiq:
-	if (ret) {
-		free_percpu(fiq_stack);
-		fiq_stack = NULL;
-	}
 err_alloc_fiq_stack:
+	for_each_possible_cpu(cpu) {
+		__free_pages(per_cpu(fiq_stack, cpu), THREAD_SIZE_ORDER);
+		per_cpu(fiq_stack, cpu) = NULL;
+	}
 err_busy:
 	mutex_unlock(&fiq_glue_lock);
 	return ret;
@@ -85,7 +93,7 @@ void fiq_glue_resume(void)
 	if (!current_handler)
 		return;
 	fiq_glue_setup(current_handler->fiq, current_handler,
-			__this_cpu_ptr(fiq_stack) + THREAD_START_SP);
+		__get_cpu_var(fiq_stack) + THREAD_START_SP);
 	if (current_handler->resume)
 		current_handler->resume(current_handler);
 }