5 files changed, 49 insertions, 12 deletions

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index b8b8560bfb95..f785aef65799 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -26,6 +26,7 @@
 #include <linux/export.h>
 #include <linux/time.h>
 #include <linux/uaccess.h>
+#include <linux/list.h>
 
 #include <trace/events/block.h>
 
@@ -38,6 +39,9 @@ static unsigned int blktrace_seq __read_mostly = 1;
 static struct trace_array *blk_tr;
 static bool blk_tracer_enabled __read_mostly;
 
+static LIST_HEAD(running_trace_list);
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(running_trace_lock);
+
 /* Select an alternative, minimalistic output than the original one */
 #define TRACE_BLK_OPT_CLASSIC	0x1
 
@@ -107,10 +111,18 @@ record_it:
  * Send out a notify for this process, if we haven't done so since a trace
  * started
  */
-static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk)
+static void trace_note_tsk(struct task_struct *tsk)
 {
+	unsigned long flags;
+	struct blk_trace *bt;
+
 	tsk->btrace_seq = blktrace_seq;
-	trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm));
+	spin_lock_irqsave(&running_trace_lock, flags);
+	list_for_each_entry(bt, &running_trace_list, running_list) {
+		trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm,
+			   sizeof(tsk->comm));
+	}
+	spin_unlock_irqrestore(&running_trace_lock, flags);
 }
 
 static void trace_note_time(struct blk_trace *bt)
@@ -229,16 +241,15 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
 		goto record_it;
 	}
 
+	if (unlikely(tsk->btrace_seq != blktrace_seq))
+		trace_note_tsk(tsk);
+
 	/*
 	 * A word about the locking here - we disable interrupts to reserve
 	 * some space in the relay per-cpu buffer, to prevent an irq
 	 * from coming in and stepping on our toes.
 	 */
 	local_irq_save(flags);
-
-	if (unlikely(tsk->btrace_seq != blktrace_seq))
-		trace_note_tsk(bt, tsk);
-
 	t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len);
 	if (t) {
 		sequence = per_cpu_ptr(bt->sequence, cpu);
@@ -477,6 +488,7 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	bt->dir = dir;
 	bt->dev = dev;
 	atomic_set(&bt->dropped, 0);
+	INIT_LIST_HEAD(&bt->running_list);
 
 	ret = -EIO;
 	bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt,
@@ -567,13 +579,12 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
 		.end_lba = cbuts.end_lba,
 		.pid = cbuts.pid,
 	};
-	memcpy(&buts.name, &cbuts.name, 32);
 
 	ret = do_blk_trace_setup(q, name, dev, bdev, &buts);
 	if (ret)
 		return ret;
 
-	if (copy_to_user(arg, &buts.name, 32)) {
+	if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) {
 		blk_trace_remove(q);
 		return -EFAULT;
 	}
@@ -601,6 +612,9 @@ int blk_trace_startstop(struct request_queue *q, int start)
 			blktrace_seq++;
 			smp_mb();
 			bt->trace_state = Blktrace_running;
+			spin_lock_irq(&running_trace_lock);
+			list_add(&bt->running_list, &running_trace_list);
+			spin_unlock_irq(&running_trace_lock);
 
 			trace_note_time(bt);
 			ret = 0;
@@ -608,6 +622,9 @@ int blk_trace_startstop(struct request_queue *q, int start)
 	} else {
 		if (bt->trace_state == Blktrace_running) {
 			bt->trace_state = Blktrace_stopped;
+			spin_lock_irq(&running_trace_lock);
+			list_del_init(&bt->running_list);
+			spin_unlock_irq(&running_trace_lock);
 			relay_flush(bt->rchan);
 			ret = 0;
 		}
@@ -1472,6 +1489,9 @@ static int blk_trace_remove_queue(struct request_queue *q)
 	if (atomic_dec_and_test(&blk_probes_ref))
 		blk_unregister_tracepoints();
 
+	spin_lock_irq(&running_trace_lock);
+	list_del(&bt->running_list);
+	spin_unlock_irq(&running_trace_lock);
 	blk_trace_free(bt);
 	return 0;
 }
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d72a15c0b32c..9d20cd9743ef 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1517,7 +1517,8 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 #endif
 		((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
 		((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
-		(need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
+		(tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) |
+		(test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0);
 }
 EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 7ca1993c33e4..ea189e027b80 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -124,6 +124,7 @@ enum trace_flag_type {
 	TRACE_FLAG_NEED_RESCHED		= 0x04,
 	TRACE_FLAG_HARDIRQ		= 0x08,
 	TRACE_FLAG_SOFTIRQ		= 0x10,
+	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
 };
 
 #define TRACE_BUF_SIZE		1024
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 80c36bcf66e8..78e27e3b52ac 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -26,7 +26,7 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
 {
 	/* The ftrace function trace is allowed only for root. */
 	if (ftrace_event_is_function(tp_event) &&
-	    perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+	    perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
 	/* No tracing, just counting, so no obvious leak */
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 34e7cbac0c9c..ed32284fbe32 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -618,8 +618,23 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
 		'.';
-	need_resched =
-		(entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
+
+	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
+				TRACE_FLAG_PREEMPT_RESCHED)) {
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'N';
+		break;
+	case TRACE_FLAG_NEED_RESCHED:
+		need_resched = 'n';
+		break;
+	case TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'p';
+		break;
+	default:
+		need_resched = '.';
+		break;
+	}
+
 	hardsoft_irq =
 		(hardirq && softirq) ? 'H' :
 		hardirq ? 'h' :