Merge branch 'perf/core' of...

Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core

MAINTAINERS

@@ -5644,7 +5644,7 @@ TRACING
 M:	Steven Rostedt <rostedt@goodmis.org>
 M:	Frederic Weisbecker <fweisbec@gmail.com>
 M:	Ingo Molnar <mingo@redhat.com>
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git tracing/core
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git perf/core
 S:	Maintained
 F:	Documentation/trace/ftrace.txt
 F:	arch/*/*/*/ftrace.h

include/asm-generic/vmlinux.lds.h

@@ -150,10 +150,6 @@
 	CPU_KEEP(exit.data)						\
 	MEM_KEEP(init.data)						\
 	MEM_KEEP(exit.data)						\
-	. = ALIGN(8);							\
-	VMLINUX_SYMBOL(__start___markers) = .;				\
-	*(__markers)							\
-	VMLINUX_SYMBOL(__stop___markers) = .;				\
 	. = ALIGN(32);							\
 	VMLINUX_SYMBOL(__start___tracepoints) = .;			\
 	*(__tracepoints)						\

kernel/trace/Kconfig

@@ -308,28 +308,6 @@ config BRANCH_TRACER
 
 	  Say N if unsure.
 
-config KSYM_TRACER
-	bool "Trace read and write access on kernel memory locations"
-	depends on HAVE_HW_BREAKPOINT
-	select TRACING
-	help
-	  This tracer helps find read and write operations on any given kernel
-	  symbol i.e. /proc/kallsyms.
-
-config PROFILE_KSYM_TRACER
-	bool "Profile all kernel memory accesses on 'watched' variables"
-	depends on KSYM_TRACER
-	help
-	  This tracer profiles kernel accesses on variables watched through the
-	  ksym tracer ftrace plugin. Depending upon the hardware, all read
-	  and write operations on kernel variables can be monitored for
-	  accesses.
-
-	  The results will be displayed in:
-	  /debugfs/tracing/profile_ksym
-
-	  Say N if unsure.
-
 config STACK_TRACER
 	bool "Trace max stack"
 	depends on HAVE_FUNCTION_TRACER

kernel/trace/Makefile

@@ -53,7 +53,6 @@ obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o
 endif
 obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
 obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o
-obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o
 obj-$(CONFIG_EVENT_TRACING) += power-traces.o
 
 libftrace-y := ftrace.o

kernel/trace/trace.h

@@ -30,7 +30,6 @@ enum trace_type {
 	TRACE_GRAPH_ENT,
 	TRACE_USER_STACK,
 	TRACE_BLK,
-	TRACE_KSYM,
 
 	__TRACE_LAST_TYPE,
 };
@@ -200,7 +199,6 @@ extern void __ftrace_bad_type(void);
 			  TRACE_GRAPH_ENT);		\
 		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
 			  TRACE_GRAPH_RET);		\
-		IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\
 		__ftrace_bad_type();					\
 	} while (0)
 
@@ -361,8 +359,6 @@ int register_tracer(struct tracer *type);
 void unregister_tracer(struct tracer *type);
 int is_tracing_stopped(void);
 
-extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
-
 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
 
 extern unsigned long tracing_thresh;
@@ -436,8 +432,6 @@ extern int trace_selftest_startup_sysprof(struct tracer *trace,
 					       struct trace_array *tr);
 extern int trace_selftest_startup_branch(struct tracer *trace,
 					 struct trace_array *tr);
-extern int trace_selftest_startup_ksym(struct tracer *trace,
-					 struct trace_array *tr);
 #endif /* CONFIG_FTRACE_STARTUP_TEST */
 
 extern void *head_page(struct trace_array_cpu *data);

kernel/trace/trace_entries.h

@@ -291,18 +291,3 @@ FTRACE_ENTRY(branch, trace_branch,
 		 __entry->func, __entry->file, __entry->correct)
 );
 
-FTRACE_ENTRY(ksym_trace, ksym_trace_entry,
-
-	TRACE_KSYM,
-
-	F_STRUCT(
-		__field(	unsigned long,	ip			  )
-		__field(	unsigned char,	type			  )
-		__array(	char	     ,	cmd,	   TASK_COMM_LEN  )
-		__field(	unsigned long,  addr			  )
-	),
-
-	F_printk("ip: %pF type: %d ksym_name: %pS cmd: %s",
-		(void *)__entry->ip, (unsigned int)__entry->type,
-		(void *)__entry->addr,  __entry->cmd)
-);

kernel/trace/trace_ksym.c

-/*
- * trace_ksym.c - Kernel Symbol Tracer
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright (C) IBM Corporation, 2009
- */
-
-#include <linux/kallsyms.h>
-#include <linux/uaccess.h>
-#include <linux/debugfs.h>
-#include <linux/ftrace.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
-
-#include "trace_output.h"
-#include "trace.h"
-
-#include <linux/hw_breakpoint.h>
-#include <asm/hw_breakpoint.h>
-
-#include <asm/atomic.h>
-
-#define KSYM_TRACER_OP_LEN 3 /* rw- */
-
-struct trace_ksym {
-	struct perf_event	**ksym_hbp;
-	struct perf_event_attr	attr;
-#ifdef CONFIG_PROFILE_KSYM_TRACER
-	atomic64_t		counter;
-#endif
-	struct hlist_node	ksym_hlist;
-};
-
-static struct trace_array *ksym_trace_array;
-
-static unsigned int ksym_tracing_enabled;
-
-static HLIST_HEAD(ksym_filter_head);
-
-static DEFINE_MUTEX(ksym_tracer_mutex);
-
-#ifdef CONFIG_PROFILE_KSYM_TRACER
-
-#define MAX_UL_INT 0xffffffff
-
-void ksym_collect_stats(unsigned long hbp_hit_addr)
-{
-	struct hlist_node *node;
-	struct trace_ksym *entry;
-
-	rcu_read_lock();
-	hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) {
-		if (entry->attr.bp_addr == hbp_hit_addr) {
-			atomic64_inc(&entry->counter);
-			break;
-		}
-	}
-	rcu_read_unlock();
-}
-#endif /* CONFIG_PROFILE_KSYM_TRACER */
-
-void ksym_hbp_handler(struct perf_event *hbp, int nmi,
-		      struct perf_sample_data *data,
-		      struct pt_regs *regs)
-{
-	struct ring_buffer_event *event;
-	struct ksym_trace_entry *entry;
-	struct ring_buffer *buffer;
-	int pc;
-
-	if (!ksym_tracing_enabled)
-		return;
-
-	buffer = ksym_trace_array->buffer;
-
-	pc = preempt_count();
-
-	event = trace_buffer_lock_reserve(buffer, TRACE_KSYM,
-							sizeof(*entry), 0, pc);
-	if (!event)
-		return;
-
-	entry		= ring_buffer_event_data(event);
-	entry->ip	= instruction_pointer(regs);
-	entry->type	= hw_breakpoint_type(hbp);
-	entry->addr	= hw_breakpoint_addr(hbp);
-	strlcpy(entry->cmd, current->comm, TASK_COMM_LEN);
-
-#ifdef CONFIG_PROFILE_KSYM_TRACER
-	ksym_collect_stats(hw_breakpoint_addr(hbp));
-#endif /* CONFIG_PROFILE_KSYM_TRACER */
-
-	trace_buffer_unlock_commit(buffer, event, 0, pc);
-}
-
-/* Valid access types are represented as
- *
- * rw- : Set Read/Write Access Breakpoint
- * -w- : Set Write Access Breakpoint
- * --- : Clear Breakpoints
- * --x : Set Execution Break points (Not available yet)
- *
- */
-static int ksym_trace_get_access_type(char *str)
-{
-	int access = 0;
-
-	if (str[0] == 'r')
-		access |= HW_BREAKPOINT_R;
-
-	if (str[1] == 'w')
-		access |= HW_BREAKPOINT_W;
-
-	if (str[2] == 'x')
-		access |= HW_BREAKPOINT_X;
-
-	switch (access) {
-	case HW_BREAKPOINT_R:
-	case HW_BREAKPOINT_W:
-	case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
-		return access;
-	default:
-		return -EINVAL;
-	}
-}
-
-/*
- * There can be several possible malformed requests and we attempt to capture
- * all of them. We enumerate some of the rules
- * 1. We will not allow kernel symbols with ':' since it is used as a delimiter.
- *    i.e. multiple ':' symbols disallowed. Possible uses are of the form
- *    <module>:<ksym_name>:<op>.
- * 2. No delimiter symbol ':' in the input string
- * 3. Spurious operator symbols or symbols not in their respective positions
- * 4. <ksym_name>:--- i.e. clear breakpoint request when ksym_name not in file
- * 5. Kernel symbol not a part of /proc/kallsyms
- * 6. Duplicate requests
- */
-static int parse_ksym_trace_str(char *input_string, char **ksymname,
-							unsigned long *addr)
-{
-	int ret;
-
-	*ksymname = strsep(&input_string, ":");
-	*addr = kallsyms_lookup_name(*ksymname);
-
-	/* Check for malformed request: (2), (1) and (5) */
-	if ((!input_string) ||
-	    (strlen(input_string) != KSYM_TRACER_OP_LEN) ||
-	    (*addr == 0))
-		return -EINVAL;;
-
-	ret = ksym_trace_get_access_type(input_string);
-
-	return ret;
-}
-
-int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
-{
-	struct trace_ksym *entry;
-	int ret = -ENOMEM;
-
-	entry = kzalloc(sizeof(struct trace_ksym), GFP_KERNEL);
-	if (!entry)
-		return -ENOMEM;
-
-	hw_breakpoint_init(&entry->attr);
-
-	entry->attr.bp_type = op;
-	entry->attr.bp_addr = addr;
-	entry->attr.bp_len = HW_BREAKPOINT_LEN_4;
-
-	entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr,
-					ksym_hbp_handler);
-
-	if (IS_ERR(entry->ksym_hbp)) {
-		ret = PTR_ERR(entry->ksym_hbp);
-		if (ret == -ENOSPC) {
-			printk(KERN_ERR "ksym_tracer: Maximum limit reached."
-			" No new requests for tracing can be accepted now.\n");
-		} else {
-			printk(KERN_INFO "ksym_tracer request failed. Try again"
-					 " later!!\n");
-		}
-		goto err;
-	}
-
-	hlist_add_head_rcu(&(entry->ksym_hlist), &ksym_filter_head);
-
-	return 0;
-
-err:
-	kfree(entry);
-
-	return ret;
-}
-
-static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf,
-						size_t count, loff_t *ppos)
-{
-	struct trace_ksym *entry;
-	struct hlist_node *node;
-	struct trace_seq *s;
-	ssize_t cnt = 0;
-	int ret;
-
-	s = kmalloc(sizeof(*s), GFP_KERNEL);
-	if (!s)
-		return -ENOMEM;
-	trace_seq_init(s);
-
-	mutex_lock(&ksym_tracer_mutex);
-
-	hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
-		ret = trace_seq_printf(s, "%pS:",
-				(void *)(unsigned long)entry->attr.bp_addr);
-		if (entry->attr.bp_type == HW_BREAKPOINT_R)
-			ret = trace_seq_puts(s, "r--\n");
-		else if (entry->attr.bp_type == HW_BREAKPOINT_W)
-			ret = trace_seq_puts(s, "-w-\n");
-		else if (entry->attr.bp_type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R))
-			ret = trace_seq_puts(s, "rw-\n");
-		WARN_ON_ONCE(!ret);
-	}
-
-	cnt = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
-
-	mutex_unlock(&ksym_tracer_mutex);
-
-	kfree(s);
-
-	return cnt;
-}
-
-static void __ksym_trace_reset(void)
-{
-	struct trace_ksym *entry;
-	struct hlist_node *node, *node1;
-
-	mutex_lock(&ksym_tracer_mutex);
-	hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head,
-								ksym_hlist) {
-		unregister_wide_hw_breakpoint(entry->ksym_hbp);
-		hlist_del_rcu(&(entry->ksym_hlist));
-		synchronize_rcu();
-		kfree(entry);
-	}
-	mutex_unlock(&ksym_tracer_mutex);
-}
-
-static ssize_t ksym_trace_filter_write(struct file *file,
-					const char __user *buffer,
-						size_t count, loff_t *ppos)
-{
-	struct trace_ksym *entry;
-	struct hlist_node *node;
-	char *buf, *input_string, *ksymname = NULL;
-	unsigned long ksym_addr = 0;
-	int ret, op, changed = 0;
-
-	buf = kzalloc(count + 1, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	ret = -EFAULT;
-	if (copy_from_user(buf, buffer, count))
-		goto out;
-
-	buf[count] = '\0';
-	input_string = strstrip(buf);
-
-	/*
-	 * Clear all breakpoints if:
-	 * 1: echo > ksym_trace_filter
-	 * 2: echo 0 > ksym_trace_filter
-	 * 3: echo "*:---" > ksym_trace_filter
-	 */
-	if (!input_string[0] || !strcmp(input_string, "0") ||
-	    !strcmp(input_string, "*:---")) {
-		__ksym_trace_reset();
-		ret = 0;
-		goto out;
-	}
-
-	ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr);
-	if (ret < 0)
-		goto out;
-
-	mutex_lock(&ksym_tracer_mutex);
-
-	ret = -EINVAL;
-	hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
-		if (entry->attr.bp_addr == ksym_addr) {
-			/* Check for malformed request: (6) */
-			if (entry->attr.bp_type != op)
-				changed = 1;
-			else
-				goto out_unlock;
-			break;
-		}
-	}
-	if (changed) {
-		unregister_wide_hw_breakpoint(entry->ksym_hbp);
-		entry->attr.bp_type = op;
-		ret = 0;
-		if (op > 0) {
-			entry->ksym_hbp =
-				register_wide_hw_breakpoint(&entry->attr,
-					ksym_hbp_handler);
-			if (IS_ERR(entry->ksym_hbp))
-				ret = PTR_ERR(entry->ksym_hbp);
-			else
-				goto out_unlock;
-		}
-		/* Error or "symbol:---" case: drop it */
-		hlist_del_rcu(&(entry->ksym_hlist));
-		synchronize_rcu();
-		kfree(entry);
-		goto out_unlock;
-	} else {
-		/* Check for malformed request: (4) */
-		if (op)
-			ret = process_new_ksym_entry(ksymname, op, ksym_addr);
-	}
-out_unlock:
-	mutex_unlock(&ksym_tracer_mutex);
-out:
-	kfree(buf);
-	return !ret ? count : ret;
-}
-
-static const struct file_operations ksym_tracing_fops = {
-	.open		= tracing_open_generic,
-	.read		= ksym_trace_filter_read,
-	.write		= ksym_trace_filter_write,
-};
-
-static void ksym_trace_reset(struct trace_array *tr)
-{
-	ksym_tracing_enabled = 0;
-	__ksym_trace_reset();
-}
-
-static int ksym_trace_init(struct trace_array *tr)
-{
-	int cpu, ret = 0;
-
-	for_each_online_cpu(cpu)
-		tracing_reset(tr, cpu);
-	ksym_tracing_enabled = 1;
-	ksym_trace_array = tr;
-
-	return ret;
-}
-
-static void ksym_trace_print_header(struct seq_file *m)
-{
-	seq_puts(m,
-		 "#       TASK-PID   CPU#      Symbol                    "
-		 "Type    Function\n");
-	seq_puts(m,
-		 "#          |        |          |                       "
-		 " |         |\n");
-}
-
-static enum print_line_t ksym_trace_output(struct trace_iterator *iter)
-{
-	struct trace_entry *entry = iter->ent;
-	struct trace_seq *s = &iter->seq;
-	struct ksym_trace_entry *field;
-	char str[KSYM_SYMBOL_LEN];
-	int ret;
-
-	if (entry->type != TRACE_KSYM)
-		return TRACE_TYPE_UNHANDLED;
-
-	trace_assign_type(field, entry);
-
-	ret = trace_seq_printf(s, "%11s-%-5d [%03d] %pS", field->cmd,
-				entry->pid, iter->cpu, (char *)field->addr);
-	if (!ret)
-		return TRACE_TYPE_PARTIAL_LINE;
-
-	switch (field->type) {
-	case HW_BREAKPOINT_R:
-		ret = trace_seq_printf(s, " R  ");
-		break;
-	case HW_BREAKPOINT_W:
-		ret = trace_seq_printf(s, " W  ");
-		break;
-	case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
-		ret = trace_seq_printf(s, " RW ");
-		break;
-	default:
-		return TRACE_TYPE_PARTIAL_LINE;
-	}
-
-	if (!ret)
-		return TRACE_TYPE_PARTIAL_LINE;
-
-	sprint_symbol(str, field->ip);
-	ret = trace_seq_printf(s, "%s\n", str);
-	if (!ret)
-		return TRACE_TYPE_PARTIAL_LINE;
-
-	return TRACE_TYPE_HANDLED;
-}
-
-struct tracer ksym_tracer __read_mostly =
-{
-	.name		= "ksym_tracer",
-	.init		= ksym_trace_init,
-	.reset		= ksym_trace_reset,
-#ifdef CONFIG_FTRACE_SELFTEST
-	.selftest	= trace_selftest_startup_ksym,
-#endif
-	.print_header   = ksym_trace_print_header,
-	.print_line	= ksym_trace_output
-};
-
-#ifdef CONFIG_PROFILE_KSYM_TRACER
-static int ksym_profile_show(struct seq_file *m, void *v)
-{
-	struct hlist_node *node;
-	struct trace_ksym *entry;
-	int access_type = 0;
-	char fn_name[KSYM_NAME_LEN];
-
-	seq_puts(m, "  Access Type ");
-	seq_puts(m, "  Symbol                                       Counter\n");
-	seq_puts(m, "  ----------- ");
-	seq_puts(m, "  ------                                       -------\n");
-
-	rcu_read_lock();
-	hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) {
-
-		access_type = entry->attr.bp_type;
-
-		switch (access_type) {
-		case HW_BREAKPOINT_R:
-			seq_puts(m, "  R           ");
-			break;
-		case HW_BREAKPOINT_W:
-			seq_puts(m, "  W           ");
-			break;
-		case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
-			seq_puts(m, "  RW          ");
-			break;
-		default:
-			seq_puts(m, "  NA          ");
-		}
-
-		if (lookup_symbol_name(entry->attr.bp_addr, fn_name) >= 0)
-			seq_printf(m, "  %-36s", fn_name);
-		else
-			seq_printf(m, "  %-36s", "<NA>");
-		seq_printf(m, " %15llu\n",
-			   (unsigned long long)atomic64_read(&entry->counter));
-	}
-	rcu_read_unlock();
-
-	return 0;
-}
-
-static int ksym_profile_open(struct inode *node, struct file *file)
-{
-	return single_open(file, ksym_profile_show, NULL);
-}
-
-static const struct file_operations ksym_profile_fops = {
-	.open		= ksym_profile_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-};
-#endif /* CONFIG_PROFILE_KSYM_TRACER */
-
-__init static int init_ksym_trace(void)
-{
-	struct dentry *d_tracer;
-
-	d_tracer = tracing_init_dentry();
-
-	trace_create_file("ksym_trace_filter", 0644, d_tracer,
-			  NULL, &ksym_tracing_fops);
-
-#ifdef CONFIG_PROFILE_KSYM_TRACER
-	trace_create_file("ksym_profile", 0444, d_tracer,
-			  NULL, &ksym_profile_fops);
-#endif
-
-	return register_tracer(&ksym_tracer);
-}
-device_initcall(init_ksym_trace);

kernel/trace/trace_selftest.c

@@ -17,7 +17,6 @@ static inline int trace_valid_entry(struct trace_entry *entry)
 	case TRACE_BRANCH:
 	case TRACE_GRAPH_ENT:
 	case TRACE_GRAPH_RET:
-	case TRACE_KSYM:
 		return 1;
 	}
 	return 0;
@@ -755,56 +754,3 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
 }
 #endif /* CONFIG_BRANCH_TRACER */
 
-#ifdef CONFIG_KSYM_TRACER
-static int ksym_selftest_dummy;
-
-int
-trace_selftest_startup_ksym(struct tracer *trace, struct trace_array *tr)
-{
-	unsigned long count;
-	int ret;
-
-	/* start the tracing */
-	ret = tracer_init(trace, tr);
-	if (ret) {
-		warn_failed_init_tracer(trace, ret);
-		return ret;
-	}
-
-	ksym_selftest_dummy = 0;
-	/* Register the read-write tracing request */
-
-	ret = process_new_ksym_entry("ksym_selftest_dummy",
-				     HW_BREAKPOINT_R | HW_BREAKPOINT_W,
-					(unsigned long)(&ksym_selftest_dummy));
-
-	if (ret < 0) {
-		printk(KERN_CONT "ksym_trace read-write startup test failed\n");
-		goto ret_path;
-	}
-	/* Perform a read and a write operation over the dummy variable to
-	 * trigger the tracer
-	 */
-	if (ksym_selftest_dummy == 0)
-		ksym_selftest_dummy++;
-
-	/* stop the tracing. */
-	tracing_stop();
-	/* check the trace buffer */
-	ret = trace_test_buffer(tr, &count);
-	trace->reset(tr);
-	tracing_start();
-
-	/* read & write operations - one each is performed on the dummy variable
-	 * triggering two entries in the trace buffer
-	 */
-	if (!ret && count != 2) {
-		printk(KERN_CONT "Ksym tracer startup test failed");
-		ret = -1;
-	}
-
-ret_path:
-	return ret;
-}
-#endif /* CONFIG_KSYM_TRACER */
-