Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 167 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
new file mode 100644
index 000000000..5677c4a08
--- /dev/null
+++ b/arch/arm/mach-omap2/timer.c
@@ -0,0 +1,167 @@
+/*
+ * linux/arch/arm/mach-omap2/timer.c
+ *
+ * OMAP2 GP timer support.
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ *
+ * Update to use new clocksource/clockevent layers
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ *
+ * Original driver:
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Paul Mundt <paul.mundt@nokia.com>
+ *         Juha Yrjölä <juha.yrjola@nokia.com>
+ * OMAP Dual-mode timer framework support by Timo Teras
+ *
+ * Some parts based off of TI's 24xx code:
+ *
+ * Copyright (C) 2004-2009 Texas Instruments, Inc.
+ *
+ * Roughly modelled after the OMAP1 MPU timer code.
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+
+#include "soc.h"
+#include "common.h"
+#include "control.h"
+#include "omap-secure.h"
+
+#define REALTIME_COUNTER_BASE				0x48243200
+#define INCREMENTER_NUMERATOR_OFFSET			0x10
+#define INCREMENTER_DENUMERATOR_RELOAD_OFFSET		0x14
+#define NUMERATOR_DENUMERATOR_MASK			0xfffff000
+
+static unsigned long arch_timer_freq;
+
+void set_cntfreq(void)
+{
+	omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
+}
+
+/*
+ * The realtime counter also called master counter, is a free-running
+ * counter, which is related to real time. It produces the count used
+ * by the CPU local timer peripherals in the MPU cluster. The timer counts
+ * at a rate of 6.144 MHz. Because the device operates on different clocks
+ * in different power modes, the master counter shifts operation between
+ * clocks, adjusting the increment per clock in hardware accordingly to
+ * maintain a constant count rate.
+ */
+static void __init realtime_counter_init(void)
+{
+	void __iomem *base;
+	static struct clk *sys_clk;
+	unsigned long rate;
+	unsigned int reg;
+	unsigned long long num, den;
+
+	base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
+	if (!base) {
+		pr_err("%s: ioremap failed\n", __func__);
+		return;
+	}
+	sys_clk = clk_get(NULL, "sys_clkin");
+	if (IS_ERR(sys_clk)) {
+		pr_err("%s: failed to get system clock handle\n", __func__);
+		iounmap(base);
+		return;
+	}
+
+	rate = clk_get_rate(sys_clk);
+	clk_put(sys_clk);
+
+	if (soc_is_dra7xx()) {
+		/*
+		 * Errata i856 says the 32.768KHz crystal does not start at
+		 * power on, so the CPU falls back to an emulated 32KHz clock
+		 * based on sysclk / 610 instead. This causes the master counter
+		 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
+		 * (OR sysclk * 75 / 244)
+		 *
+		 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
+		 * Of course any board built without a populated 32.768KHz
+		 * crystal would also need this fix even if the CPU is fixed
+		 * later.
+		 *
+		 * Either case can be detected by using the two speedselect bits
+		 * If they are not 0, then the 32.768KHz clock driving the
+		 * coarse counter that corrects the fine counter every time it
+		 * ticks is actually rate/610 rather than 32.768KHz and we
+		 * should compensate to avoid the 570ppm (at 20MHz, much worse
+		 * at other rates) too fast system time.
+		 */
+		reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
+		if (reg & DRA7_SPEEDSELECT_MASK) {
+			num = 75;
+			den = 244;
+			goto sysclk1_based;
+		}
+	}
+
+	/* Numerator/denumerator values refer TRM Realtime Counter section */
+	switch (rate) {
+	case 12000000:
+		num = 64;
+		den = 125;
+		break;
+	case 13000000:
+		num = 768;
+		den = 1625;
+		break;
+	case 19200000:
+		num = 8;
+		den = 25;
+		break;
+	case 20000000:
+		num = 192;
+		den = 625;
+		break;
+	case 26000000:
+		num = 384;
+		den = 1625;
+		break;
+	case 27000000:
+		num = 256;
+		den = 1125;
+		break;
+	case 38400000:
+	default:
+		/* Program it for 38.4 MHz */
+		num = 4;
+		den = 25;
+		break;
+	}
+
+sysclk1_based:
+	/* Program numerator and denumerator registers */
+	reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
+			NUMERATOR_DENUMERATOR_MASK;
+	reg |= num;
+	writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
+
+	reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
+			NUMERATOR_DENUMERATOR_MASK;
+	reg |= den;
+	writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
+
+	arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
+	set_cntfreq();
+
+	iounmap(base);
+}
+
+void __init omap5_realtime_timer_init(void)
+{
+	omap_clk_init();
+	realtime_counter_init();
+
+	timer_probe();
+}