Merge branch 'linus' into stackprotector

Conflicts:
	arch/x86/include/asm/pda.h
	kernel/fork.c

1 files changed, 669 insertions, 0 deletions

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
new file mode 100644
index 00000000000..4bf39fcae97
--- /dev/null
+++ b/kernel/trace/trace_functions_graph.c
@@ -0,0 +1,669 @@
+/*
+ *
+ * Function graph tracer.
+ * Copyright (c) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ * Mostly borrowed from function tracer which
+ * is Copyright (c) Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/fs.h>
+
+#include "trace.h"
+
+#define TRACE_GRAPH_INDENT	2
+
+/* Flag options */
+#define TRACE_GRAPH_PRINT_OVERRUN	0x1
+#define TRACE_GRAPH_PRINT_CPU		0x2
+#define TRACE_GRAPH_PRINT_OVERHEAD	0x4
+#define TRACE_GRAPH_PRINT_PROC		0x8
+
+static struct tracer_opt trace_opts[] = {
+	/* Display overruns ? */
+	{ TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) },
+	/* Display CPU ? */
+	{ TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) },
+	/* Display Overhead ? */
+	{ TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) },
+	/* Display proc name/pid */
+	{ TRACER_OPT(funcgraph-proc, TRACE_GRAPH_PRINT_PROC) },
+	{ } /* Empty entry */
+};
+
+static struct tracer_flags tracer_flags = {
+	/* Don't display overruns and proc by default */
+	.val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD,
+	.opts = trace_opts
+};
+
+/* pid on the last trace processed */
+static pid_t last_pid[NR_CPUS] = { [0 ... NR_CPUS-1] = -1 };
+
+static int graph_trace_init(struct trace_array *tr)
+{
+	int cpu, ret;
+
+	for_each_online_cpu(cpu)
+		tracing_reset(tr, cpu);
+
+	ret = register_ftrace_graph(&trace_graph_return,
+					&trace_graph_entry);
+	if (ret)
+		return ret;
+	tracing_start_cmdline_record();
+
+	return 0;
+}
+
+static void graph_trace_reset(struct trace_array *tr)
+{
+	tracing_stop_cmdline_record();
+	unregister_ftrace_graph();
+}
+
+static inline int log10_cpu(int nb)
+{
+	if (nb / 100)
+		return 3;
+	if (nb / 10)
+		return 2;
+	return 1;
+}
+
+static enum print_line_t
+print_graph_cpu(struct trace_seq *s, int cpu)
+{
+	int i;
+	int ret;
+	int log10_this = log10_cpu(cpu);
+	int log10_all = log10_cpu(cpus_weight_nr(cpu_online_map));
+
+
+	/*
+	 * Start with a space character - to make it stand out
+	 * to the right a bit when trace output is pasted into
+	 * email:
+	 */
+	ret = trace_seq_printf(s, " ");
+
+	/*
+	 * Tricky - we space the CPU field according to the max
+	 * number of online CPUs. On a 2-cpu system it would take
+	 * a maximum of 1 digit - on a 128 cpu system it would
+	 * take up to 3 digits:
+	 */
+	for (i = 0; i < log10_all - log10_this; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+	ret = trace_seq_printf(s, "%d) ", cpu);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+#define TRACE_GRAPH_PROCINFO_LENGTH	14
+
+static enum print_line_t
+print_graph_proc(struct trace_seq *s, pid_t pid)
+{
+	int i;
+	int ret;
+	int len;
+	char comm[8];
+	int spaces = 0;
+	/* sign + log10(MAX_INT) + '\0' */
+	char pid_str[11];
+
+	strncpy(comm, trace_find_cmdline(pid), 7);
+	comm[7] = '\0';
+	sprintf(pid_str, "%d", pid);
+
+	/* 1 stands for the "-" character */
+	len = strlen(comm) + strlen(pid_str) + 1;
+
+	if (len < TRACE_GRAPH_PROCINFO_LENGTH)
+		spaces = TRACE_GRAPH_PROCINFO_LENGTH - len;
+
+	/* First spaces to align center */
+	for (i = 0; i < spaces / 2; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = trace_seq_printf(s, "%s-%s", comm, pid_str);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Last spaces to align center */
+	for (i = 0; i < spaces - (spaces / 2); i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+	return TRACE_TYPE_HANDLED;
+}
+
+
+/* If the pid changed since the last trace, output this event */
+static enum print_line_t
+verif_pid(struct trace_seq *s, pid_t pid, int cpu)
+{
+	pid_t prev_pid;
+	int ret;
+
+	if (last_pid[cpu] != -1 && last_pid[cpu] == pid)
+		return TRACE_TYPE_HANDLED;
+
+	prev_pid = last_pid[cpu];
+	last_pid[cpu] = pid;
+
+/*
+ * Context-switch trace line:
+
+ ------------------------------------------
+ | 1)  migration/0--1  =>  sshd-1755
+ ------------------------------------------
+
+ */
+	ret = trace_seq_printf(s,
+		" ------------------------------------------\n");
+	if (!ret)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	ret = print_graph_cpu(s, cpu);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	ret = print_graph_proc(s, prev_pid);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	ret = trace_seq_printf(s, " => ");
+	if (!ret)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	ret = print_graph_proc(s, pid);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	ret = trace_seq_printf(s,
+		"\n ------------------------------------------\n\n");
+	if (!ret)
+		TRACE_TYPE_PARTIAL_LINE;
+
+	return ret;
+}
+
+static bool
+trace_branch_is_leaf(struct trace_iterator *iter,
+		struct ftrace_graph_ent_entry *curr)
+{
+	struct ring_buffer_iter *ring_iter;
+	struct ring_buffer_event *event;
+	struct ftrace_graph_ret_entry *next;
+
+	ring_iter = iter->buffer_iter[iter->cpu];
+
+	if (!ring_iter)
+		return false;
+
+	event = ring_buffer_iter_peek(ring_iter, NULL);
+
+	if (!event)
+		return false;
+
+	next = ring_buffer_event_data(event);
+
+	if (next->ent.type != TRACE_GRAPH_RET)
+		return false;
+
+	if (curr->ent.pid != next->ent.pid ||
+			curr->graph_ent.func != next->ret.func)
+		return false;
+
+	return true;
+}
+
+static enum print_line_t
+print_graph_irq(struct trace_seq *s, unsigned long addr,
+				enum trace_type type, int cpu, pid_t pid)
+{
+	int ret;
+
+	if (addr < (unsigned long)__irqentry_text_start ||
+		addr >= (unsigned long)__irqentry_text_end)
+		return TRACE_TYPE_UNHANDLED;
+
+	if (type == TRACE_GRAPH_ENT) {
+		ret = trace_seq_printf(s, "==========> |  ");
+	} else {
+		/* Cpu */
+		if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+			ret = print_graph_cpu(s, cpu);
+			if (ret == TRACE_TYPE_PARTIAL_LINE)
+				return TRACE_TYPE_PARTIAL_LINE;
+		}
+		/* Proc */
+		if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+			ret = print_graph_proc(s, pid);
+			if (ret == TRACE_TYPE_PARTIAL_LINE)
+				return TRACE_TYPE_PARTIAL_LINE;
+
+			ret = trace_seq_printf(s, " | ");
+			if (!ret)
+				return TRACE_TYPE_PARTIAL_LINE;
+		}
+
+		/* No overhead */
+		if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+			ret = trace_seq_printf(s, "  ");
+			if (!ret)
+				return TRACE_TYPE_PARTIAL_LINE;
+		}
+
+		ret = trace_seq_printf(s, "<========== |\n");
+	}
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+	return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_duration(unsigned long long duration, struct trace_seq *s)
+{
+	unsigned long nsecs_rem = do_div(duration, 1000);
+	/* log10(ULONG_MAX) + '\0' */
+	char msecs_str[21];
+	char nsecs_str[5];
+	int ret, len;
+	int i;
+
+	sprintf(msecs_str, "%lu", (unsigned long) duration);
+
+	/* Print msecs */
+	ret = trace_seq_printf(s, msecs_str);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	len = strlen(msecs_str);
+
+	/* Print nsecs (we don't want to exceed 7 numbers) */
+	if (len < 7) {
+		snprintf(nsecs_str, 8 - len, "%03lu", nsecs_rem);
+		ret = trace_seq_printf(s, ".%s", nsecs_str);
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+		len += strlen(nsecs_str);
+	}
+
+	ret = trace_seq_printf(s, " us ");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Print remaining spaces to fit the row's width */
+	for (i = len; i < 7; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = trace_seq_printf(s, "|  ");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+	return TRACE_TYPE_HANDLED;
+
+}
+
+/* Signal a overhead of time execution to the output */
+static int
+print_graph_overhead(unsigned long long duration, struct trace_seq *s)
+{
+	/* Duration exceeded 100 msecs */
+	if (duration > 100000ULL)
+		return trace_seq_printf(s, "! ");
+
+	/* Duration exceeded 10 msecs */
+	if (duration > 10000ULL)
+		return trace_seq_printf(s, "+ ");
+
+	return trace_seq_printf(s, "  ");
+}
+
+/* Case of a leaf function on its call entry */
+static enum print_line_t
+print_graph_entry_leaf(struct trace_iterator *iter,
+		struct ftrace_graph_ent_entry *entry, struct trace_seq *s)
+{
+	struct ftrace_graph_ret_entry *ret_entry;
+	struct ftrace_graph_ret *graph_ret;
+	struct ring_buffer_event *event;
+	struct ftrace_graph_ent *call;
+	unsigned long long duration;
+	int ret;
+	int i;
+
+	event = ring_buffer_read(iter->buffer_iter[iter->cpu], NULL);
+	ret_entry = ring_buffer_event_data(event);
+	graph_ret = &ret_entry->ret;
+	call = &entry->graph_ent;
+	duration = graph_ret->rettime - graph_ret->calltime;
+
+	/* Overhead */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+		ret = print_graph_overhead(duration, s);
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Duration */
+	ret = print_graph_duration(duration, s);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Function */
+	for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = seq_print_ip_sym(s, call->func, 0);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	ret = trace_seq_printf(s, "();\n");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_entry_nested(struct ftrace_graph_ent_entry *entry,
+			struct trace_seq *s, pid_t pid, int cpu)
+{
+	int i;
+	int ret;
+	struct ftrace_graph_ent *call = &entry->graph_ent;
+
+	/* No overhead */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+		ret = trace_seq_printf(s, "  ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Interrupt */
+	ret = print_graph_irq(s, call->func, TRACE_GRAPH_ENT, cpu, pid);
+	if (ret == TRACE_TYPE_UNHANDLED) {
+		/* No time */
+		ret = trace_seq_printf(s, "            |  ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	} else {
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+
+	/* Function */
+	for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = seq_print_ip_sym(s, call->func, 0);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	ret = trace_seq_printf(s, "() {\n");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
+			struct trace_iterator *iter, int cpu)
+{
+	int ret;
+	struct trace_entry *ent = iter->ent;
+
+	/* Pid */
+	if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Cpu */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+		ret = print_graph_cpu(s, cpu);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Proc */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+		ret = print_graph_proc(s, ent->pid);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+
+		ret = trace_seq_printf(s, " | ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	if (trace_branch_is_leaf(iter, field))
+		return print_graph_entry_leaf(iter, field, s);
+	else
+		return print_graph_entry_nested(field, s, iter->ent->pid, cpu);
+
+}
+
+static enum print_line_t
+print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
+		   struct trace_entry *ent, int cpu)
+{
+	int i;
+	int ret;
+	unsigned long long duration = trace->rettime - trace->calltime;
+
+	/* Pid */
+	if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Cpu */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+		ret = print_graph_cpu(s, cpu);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Proc */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+		ret = print_graph_proc(s, ent->pid);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+
+		ret = trace_seq_printf(s, " | ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Overhead */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+		ret = print_graph_overhead(duration, s);
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Duration */
+	ret = print_graph_duration(duration, s);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Closing brace */
+	for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
+		ret = trace_seq_printf(s, " ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = trace_seq_printf(s, "}\n");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Overrun */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
+		ret = trace_seq_printf(s, " (Overruns: %lu)\n",
+					trace->overrun);
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	ret = print_graph_irq(s, trace->func, TRACE_GRAPH_RET, cpu, ent->pid);
+	if (ret == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_comment(struct print_entry *trace, struct trace_seq *s,
+		   struct trace_entry *ent, struct trace_iterator *iter)
+{
+	int i;
+	int ret;
+
+	/* Pid */
+	if (verif_pid(s, ent->pid, iter->cpu) == TRACE_TYPE_PARTIAL_LINE)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Cpu */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+		ret = print_graph_cpu(s, iter->cpu);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* Proc */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
+		ret = print_graph_proc(s, ent->pid);
+		if (ret == TRACE_TYPE_PARTIAL_LINE)
+			return TRACE_TYPE_PARTIAL_LINE;
+
+		ret = trace_seq_printf(s, " | ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* No overhead */
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+		ret = trace_seq_printf(s, "  ");
+		if (!ret)
+			return TRACE_TYPE_PARTIAL_LINE;
+	}
+
+	/* No time */
+	ret = trace_seq_printf(s, "            |  ");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	/* Indentation */
+	if (trace->depth > 0)
+		for (i = 0; i < (trace->depth + 1) * TRACE_GRAPH_INDENT; i++) {
+			ret = trace_seq_printf(s, " ");
+			if (!ret)
+				return TRACE_TYPE_PARTIAL_LINE;
+		}
+
+	/* The comment */
+	ret = trace_seq_printf(s, "/* %s", trace->buf);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	if (ent->flags & TRACE_FLAG_CONT)
+		trace_seq_print_cont(s, iter);
+
+	ret = trace_seq_printf(s, " */\n");
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+
+enum print_line_t
+print_graph_function(struct trace_iterator *iter)
+{
+	struct trace_seq *s = &iter->seq;
+	struct trace_entry *entry = iter->ent;
+
+	switch (entry->type) {
+	case TRACE_GRAPH_ENT: {
+		struct ftrace_graph_ent_entry *field;
+		trace_assign_type(field, entry);
+		return print_graph_entry(field, s, iter,
+					 iter->cpu);
+	}
+	case TRACE_GRAPH_RET: {
+		struct ftrace_graph_ret_entry *field;
+		trace_assign_type(field, entry);
+		return print_graph_return(&field->ret, s, entry, iter->cpu);
+	}
+	case TRACE_PRINT: {
+		struct print_entry *field;
+		trace_assign_type(field, entry);
+		return print_graph_comment(field, s, entry, iter);
+	}
+	default:
+		return TRACE_TYPE_UNHANDLED;
+	}
+}
+
+static void print_graph_headers(struct seq_file *s)
+{
+	/* 1st line */
+	seq_printf(s, "# ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+		seq_printf(s, "CPU ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+		seq_printf(s, "TASK/PID     ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD)
+		seq_printf(s, "OVERHEAD/");
+	seq_printf(s, "DURATION            FUNCTION CALLS\n");
+
+	/* 2nd line */
+	seq_printf(s, "# ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+		seq_printf(s, "|   ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+		seq_printf(s, "|      |     ");
+	if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+		seq_printf(s, "|        ");
+		seq_printf(s, "|                   |   |   |   |\n");
+	} else
+		seq_printf(s, "    |               |   |   |   |\n");
+}
+static struct tracer graph_trace __read_mostly = {
+	.name	     	= "function_graph",
+	.init	     	= graph_trace_init,
+	.reset	     	= graph_trace_reset,
+	.print_line	= print_graph_function,
+	.print_header	= print_graph_headers,
+	.flags		= &tracer_flags,
+};
+
+static __init int init_graph_trace(void)
+{
+	return register_tracer(&graph_trace);
+}
+
+device_initcall(init_graph_trace);