Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Fixes and improvements for perf/core:

. Overhaul the tools/ makefiles, gluing them to the top level Makefile, from
  Borislav Petkov.

. Move the UI files from tools/perf/util/ui/ to tools/perf/ui/. Also move
  the GTK+ browser to tools/perf/ui/gtk/, from Namhyung Kim.

. Only fallback to sw cycles counter on ENOENT for the hw cycles, from
  Robert Richter

. Trivial fixes from Robert Richter

. Handle the autogenerated bison/flex files better, from Namhyung and Jiri Olsa.

. Navigate jump instructions in the annotate browser, just press enter or ->,
  still needs support for a jump navigation history, i.e. to go back.

. Search string in the annotate browser: same keys as vim:
     / forward
     n next backward/forward
     ? backward

. Clarify number of events/samples in the report header, from Ashay Rane

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 37 insertions, 3 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
index 0b3ea2cbd5f..b663c2c95d3 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1216,13 +1216,27 @@ int is_console_locked(void)
 	return console_locked;
 }
 
+/*
+ * Delayed printk facility, for scheduler-internal messages:
+ */
+#define PRINTK_BUF_SIZE		512
+
+#define PRINTK_PENDING_WAKEUP	0x01
+#define PRINTK_PENDING_SCHED	0x02
+
 static DEFINE_PER_CPU(int, printk_pending);
+static DEFINE_PER_CPU(char [PRINTK_BUF_SIZE], printk_sched_buf);
 
 void printk_tick(void)
 {
 	if (__this_cpu_read(printk_pending)) {
-		__this_cpu_write(printk_pending, 0);
-		wake_up_interruptible(&log_wait);
+		int pending = __this_cpu_xchg(printk_pending, 0);
+		if (pending & PRINTK_PENDING_SCHED) {
+			char *buf = __get_cpu_var(printk_sched_buf);
+			printk(KERN_WARNING "[sched_delayed] %s", buf);
+		}
+		if (pending & PRINTK_PENDING_WAKEUP)
+			wake_up_interruptible(&log_wait);
 	}
 }
 
@@ -1236,7 +1250,7 @@ int printk_needs_cpu(int cpu)
 void wake_up_klogd(void)
 {
 	if (waitqueue_active(&log_wait))
-		this_cpu_write(printk_pending, 1);
+		this_cpu_or(printk_pending, PRINTK_PENDING_WAKEUP);
 }
 
 /**
@@ -1629,6 +1643,26 @@ late_initcall(printk_late_init);
 
 #if defined CONFIG_PRINTK
 
+int printk_sched(const char *fmt, ...)
+{
+	unsigned long flags;
+	va_list args;
+	char *buf;
+	int r;
+
+	local_irq_save(flags);
+	buf = __get_cpu_var(printk_sched_buf);
+
+	va_start(args, fmt);
+	r = vsnprintf(buf, PRINTK_BUF_SIZE, fmt, args);
+	va_end(args);
+
+	__this_cpu_or(printk_pending, PRINTK_PENDING_SCHED);
+	local_irq_restore(flags);
+
+	return r;
+}
+
 /*
  * printk rate limiting, lifted from the networking subsystem.
  *