Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

Pull arch/tile updates from Chris Metcalf:
 "These fix a few stray build issues seen in linux-next, and also add
  the minimal required support for perf to tilegx"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  arch/tile: remove unused variable 'devcap'
  tile: Fix vDSO compilation issue with allyesconfig
  perf tools: Allow building for tile
  tile/perf: Support perf_events on tilegx and tilepro
  tile: Enable NMIs on return from handle_nmi() without errors
  tile: Add support for handling PMC hardware
  tile: don't use __get_cpu_var() with structure-typed arguments
  tile: avoid overflow in ns2cycles

arch/tile/Kconfig

@@ -3,6 +3,8 @@
 
 config TILE
 	def_bool y
+	select HAVE_PERF_EVENTS
+	select USE_PMC if PERF_EVENTS
 	select HAVE_DMA_ATTRS
 	select HAVE_DMA_API_DEBUG
 	select HAVE_KVM if !TILEGX
@@ -66,6 +68,10 @@ config HUGETLB_SUPER_PAGES
 config GENERIC_TIME_VSYSCALL
 	def_bool y
 
+# Enable PMC if PERF_EVENTS, OPROFILE, or WATCHPOINTS are enabled.
+config USE_PMC
+	bool
+
 # FIXME: tilegx can implement a more efficient rwsem.
 config RWSEM_GENERIC_SPINLOCK
 	def_bool y

arch/tile/include/asm/perf_event.h

+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_PERF_EVENT_H
+#define _ASM_TILE_PERF_EVENT_H
+
+#include <linux/percpu.h>
+DECLARE_PER_CPU(u64, perf_irqs);
+
+unsigned long handle_syscall_link_address(void);
+#endif /* _ASM_TILE_PERF_EVENT_H */

arch/tile/include/asm/pmc.h

+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_PMC_H
+#define _ASM_TILE_PMC_H
+
+#include <linux/ptrace.h>
+
+#define TILE_BASE_COUNTERS	2
+
+/* Bitfields below are derived from SPR PERF_COUNT_CTL*/
+#ifndef __tilegx__
+/* PERF_COUNT_CTL on TILEPro */
+#define TILE_CTL_EXCL_USER	(1 << 7) /* exclude user level */
+#define TILE_CTL_EXCL_KERNEL	(1 << 8) /* exclude kernel level */
+#define TILE_CTL_EXCL_HV	(1 << 9) /* exclude hypervisor level */
+
+#define TILE_SEL_MASK		0x7f	/* 7 bits for event SEL,
+					COUNT_0_SEL */
+#define TILE_PLM_MASK		0x780	/* 4 bits priv level msks,
+					COUNT_0_MASK*/
+#define TILE_EVENT_MASK	(TILE_SEL_MASK | TILE_PLM_MASK)
+
+#else /* __tilegx__*/
+/* PERF_COUNT_CTL on TILEGx*/
+#define TILE_CTL_EXCL_USER	(1 << 10) /* exclude user level */
+#define TILE_CTL_EXCL_KERNEL	(1 << 11) /* exclude kernel level */
+#define TILE_CTL_EXCL_HV	(1 << 12) /* exclude hypervisor level */
+
+#define TILE_SEL_MASK		0x3f	/* 6 bits for event SEL,
+					COUNT_0_SEL*/
+#define TILE_BOX_MASK		0x1c0	/* 3 bits box msks,
+					COUNT_0_BOX */
+#define TILE_PLM_MASK		0x3c00	/* 4 bits priv level msks,
+					COUNT_0_MASK */
+#define TILE_EVENT_MASK	(TILE_SEL_MASK | TILE_BOX_MASK | TILE_PLM_MASK)
+#endif /* __tilegx__*/
+
+/* Takes register and fault number.  Returns error to disable the interrupt. */
+typedef int (*perf_irq_t)(struct pt_regs *, int);
+
+int userspace_perf_handler(struct pt_regs *regs, int fault);
+
+perf_irq_t reserve_pmc_hardware(perf_irq_t new_perf_irq);
+void release_pmc_hardware(void);
+
+unsigned long pmc_get_overflow(void);
+void pmc_ack_overflow(unsigned long status);
+
+void unmask_pmc_interrupts(void);
+void mask_pmc_interrupts(void);
+
+#endif /* _ASM_TILE_PMC_H */

arch/tile/kernel/Makefile

@@ -25,6 +25,8 @@ obj-$(CONFIG_PCI)		+= pci_gx.o
 else
 obj-$(CONFIG_PCI)		+= pci.o
 endif
+obj-$(CONFIG_PERF_EVENTS)	+= perf_event.o
+obj-$(CONFIG_USE_PMC)		+= pmc.o
 obj-$(CONFIG_TILE_USB)		+= usb.o
 obj-$(CONFIG_TILE_HVGLUE_TRACE)	+= hvglue_trace.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= ftrace.o mcount_64.o

arch/tile/kernel/intvec_32.S

@@ -313,13 +313,13 @@ intvec_\vecname:
 	 movei  r3, 0
 	}
 	.else
-	.ifc \c_routine, op_handle_perf_interrupt
+	.ifc \c_routine, handle_perf_interrupt
 	{
 	 mfspr  r2, PERF_COUNT_STS
 	 movei  r3, -1   /* not used, but set for consistency */
 	}
 	.else
-	.ifc \c_routine, op_handle_aux_perf_interrupt
+	.ifc \c_routine, handle_perf_interrupt
 	{
 	 mfspr  r2, AUX_PERF_COUNT_STS
 	 movei  r3, -1   /* not used, but set for consistency */
@@ -946,6 +946,13 @@ STD_ENTRY(interrupt_return)
 	bzt     r30, .Lrestore_regs
 3:
 
+	/* We are relying on INT_PERF_COUNT at 33, and AUX_PERF_COUNT at 48 */
+	{
+	 moveli r0, lo16(1 << (INT_PERF_COUNT - 32))
+	 bz     r31, .Lrestore_regs
+	}
+	auli    r0, r0, ha16(1 << (INT_AUX_PERF_COUNT - 32))
+	mtspr   SPR_INTERRUPT_MASK_RESET_K_1, r0
 
 	/*
 	 * We now commit to returning from this interrupt, since we will be
@@ -1171,6 +1178,10 @@ handle_nmi:
 	 PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
 	}
 	FEEDBACK_REENTER(handle_nmi)
+	{
+	 movei  r30, 1
+	 seq    r31, r0, zero
+	}
 	j       interrupt_return
 	STD_ENDPROC(handle_nmi)
 
@@ -1835,8 +1846,9 @@ int_unalign:
 /* Include .intrpt array of interrupt vectors */
 	.section ".intrpt", "ax"
 
-#define op_handle_perf_interrupt bad_intr
-#define op_handle_aux_perf_interrupt bad_intr
+#ifndef CONFIG_USE_PMC
+#define handle_perf_interrupt bad_intr
+#endif
 
 #ifndef CONFIG_HARDWALL
 #define do_hardwall_trap bad_intr
@@ -1877,7 +1889,7 @@ int_unalign:
 	int_hand     INT_IDN_AVAIL, IDN_AVAIL, bad_intr
 	int_hand     INT_UDN_AVAIL, UDN_AVAIL, bad_intr
 	int_hand     INT_PERF_COUNT, PERF_COUNT, \
-		     op_handle_perf_interrupt, handle_nmi
+		     handle_perf_interrupt, handle_nmi
 	int_hand     INT_INTCTRL_3, INTCTRL_3, bad_intr
 #if CONFIG_KERNEL_PL == 2
 	dc_dispatch  INT_INTCTRL_2, INTCTRL_2
@@ -1902,7 +1914,7 @@ int_unalign:
 	int_hand     INT_SN_CPL, SN_CPL, bad_intr
 	int_hand     INT_DOUBLE_FAULT, DOUBLE_FAULT, do_trap
 	int_hand     INT_AUX_PERF_COUNT, AUX_PERF_COUNT, \
-		     op_handle_aux_perf_interrupt, handle_nmi
+		     handle_perf_interrupt, handle_nmi
 
 	/* Synthetic interrupt delivered only by the simulator */
 	int_hand     INT_BREAKPOINT, BREAKPOINT, do_breakpoint

arch/tile/kernel/intvec_64.S

@@ -509,10 +509,10 @@ intvec_\vecname:
 	.ifc \c_routine, do_trap
 	mfspr   r2, GPV_REASON
 	.else
-	.ifc \c_routine, op_handle_perf_interrupt
+	.ifc \c_routine, handle_perf_interrupt
 	mfspr   r2, PERF_COUNT_STS
 	.else
-	.ifc \c_routine, op_handle_aux_perf_interrupt
+	.ifc \c_routine, handle_perf_interrupt
 	mfspr   r2, AUX_PERF_COUNT_STS
 	.endif
 	.endif
@@ -971,6 +971,15 @@ STD_ENTRY(interrupt_return)
 	beqzt   r30, .Lrestore_regs
 3:
 
+#if INT_PERF_COUNT + 1 != INT_AUX_PERF_COUNT
+# error Bad interrupt assumption
+#endif
+	{
+	 movei  r0, 3   /* two adjacent bits for the PERF_COUNT mask */
+	 beqz   r31, .Lrestore_regs
+	}
+	shli    r0, r0, INT_PERF_COUNT
+	mtspr   SPR_INTERRUPT_MASK_RESET_K, r0
 
 	/*
 	 * We now commit to returning from this interrupt, since we will be
@@ -1187,7 +1196,7 @@ handle_nmi:
 	FEEDBACK_REENTER(handle_nmi)
 	{
 	 movei  r30, 1
-	 move   r31, r0
+	 cmpeq  r31, r0, zero
 	}
 	j       interrupt_return
 	STD_ENDPROC(handle_nmi)
@@ -1491,8 +1500,9 @@ STD_ENTRY(fill_ra_stack)
 	.global intrpt_start
 intrpt_start:
 
-#define op_handle_perf_interrupt bad_intr
-#define op_handle_aux_perf_interrupt bad_intr
+#ifndef CONFIG_USE_PMC
+#define handle_perf_interrupt bad_intr
+#endif
 
 #ifndef CONFIG_HARDWALL
 #define do_hardwall_trap bad_intr
@@ -1540,9 +1550,9 @@ intrpt_start:
 #endif
 	int_hand     INT_IPI_0, IPI_0, bad_intr
 	int_hand     INT_PERF_COUNT, PERF_COUNT, \
-		     op_handle_perf_interrupt, handle_nmi
+		     handle_perf_interrupt, handle_nmi
 	int_hand     INT_AUX_PERF_COUNT, AUX_PERF_COUNT, \
-		     op_handle_perf_interrupt, handle_nmi
+		     handle_perf_interrupt, handle_nmi
 	int_hand     INT_INTCTRL_3, INTCTRL_3, bad_intr
 #if CONFIG_KERNEL_PL == 2
 	dc_dispatch  INT_INTCTRL_2, INTCTRL_2

arch/tile/kernel/irq.c

@@ -21,6 +21,7 @@
 #include <hv/drv_pcie_rc_intf.h>
 #include <arch/spr_def.h>
 #include <asm/traps.h>
+#include <linux/perf_event.h>
 
 /* Bit-flag stored in irq_desc->chip_data to indicate HW-cleared irqs. */
 #define IS_HW_CLEARED 1
@@ -260,6 +261,23 @@ void ack_bad_irq(unsigned int irq)
 	pr_err("unexpected IRQ trap at vector %02x\n", irq);
 }
 
+/*
+ * /proc/interrupts printing:
+ */
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+#ifdef CONFIG_PERF_EVENTS
+	int i;
+
+	seq_printf(p, "%*s: ", prec, "PMI");
+
+	for_each_online_cpu(i)
+		seq_printf(p, "%10llu ", per_cpu(perf_irqs, i));
+	seq_puts(p, "  perf_events\n");
+#endif
+	return 0;
+}
+
 /*
  * Generic, controller-independent functions:
  */

arch/tile/kernel/messaging.c

@@ -68,8 +68,8 @@ void hv_message_intr(struct pt_regs *regs, int intnum)
 #endif
 
 	while (1) {
-		rmi = hv_receive_message(__get_cpu_var(msg_state),
-					 (HV_VirtAddr) message,
+		HV_MsgState *state = this_cpu_ptr(&msg_state);
+		rmi = hv_receive_message(*state, (HV_VirtAddr) message,
 					 sizeof(message));
 		if (rmi.msglen == 0)
 			break;

arch/tile/kernel/pci.c

@@ -250,8 +250,6 @@ static void fixup_read_and_payload_sizes(void)
 
 	/* Scan for the smallest maximum payload size. */
 	for_each_pci_dev(dev) {
-		u32 devcap;
-
 		if (!pci_is_pcie(dev))
 			continue;
 

arch/tile/kernel/perf_event.c

+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ *
+ * Perf_events support for Tile processor.
+ *
+ * This code is based upon the x86 perf event
+ * code, which is:
+ *
+ *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ *  Copyright (C) 2009 Jaswinder Singh Rajput
+ *  Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
+ *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ *  Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
+ *  Copyright (C) 2009 Google, Inc., Stephane Eranian
+ */
+
+#include <linux/kprobes.h>
+#include <linux/kernel.h>
+#include <linux/kdebug.h>
+#include <linux/mutex.h>
+#include <linux/bitmap.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/perf_event.h>
+#include <linux/atomic.h>
+#include <asm/traps.h>
+#include <asm/stack.h>
+#include <asm/pmc.h>
+#include <hv/hypervisor.h>
+
+#define TILE_MAX_COUNTERS	4
+
+#define PERF_COUNT_0_IDX	0
+#define PERF_COUNT_1_IDX	1
+#define AUX_PERF_COUNT_0_IDX	2
+#define AUX_PERF_COUNT_1_IDX	3
+
+struct cpu_hw_events {
+	int			n_events;
+	struct perf_event	*events[TILE_MAX_COUNTERS]; /* counter order */
+	struct perf_event	*event_list[TILE_MAX_COUNTERS]; /* enabled
+								order */
+	int			assign[TILE_MAX_COUNTERS];
+	unsigned long		active_mask[BITS_TO_LONGS(TILE_MAX_COUNTERS)];
+	unsigned long		used_mask;
+};
+
+/* TILE arch specific performance monitor unit */
+struct tile_pmu {
+	const char	*name;
+	int		version;
+	const int	*hw_events;	/* generic hw events table */
+	/* generic hw cache events table */
+	const int	(*cache_events)[PERF_COUNT_HW_CACHE_MAX]
+				       [PERF_COUNT_HW_CACHE_OP_MAX]
+				       [PERF_COUNT_HW_CACHE_RESULT_MAX];
+	int		(*map_hw_event)(u64);	 /*method used to map
+						  hw events */
+	int		(*map_cache_event)(u64); /*method used to map
+						  cache events */
+
+	u64		max_period;		/* max sampling period */
+	u64		cntval_mask;		/* counter width mask */
+	int		cntval_bits;		/* counter width */
+	int		max_events;		/* max generic hw events
+						in map */
+	int		num_counters;		/* number base + aux counters */
+	int		num_base_counters;	/* number base counters */
+};
+
+DEFINE_PER_CPU(u64, perf_irqs);
+static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
+
+#define TILE_OP_UNSUPP		(-1)
+
+#ifndef __tilegx__
+/* TILEPro hardware events map */
+static const int tile_hw_event_map[] = {
+	[PERF_COUNT_HW_CPU_CYCLES]		= 0x01, /* ONE */
+	[PERF_COUNT_HW_INSTRUCTIONS]		= 0x06, /* MP_BUNDLE_RETIRED */
+	[PERF_COUNT_HW_CACHE_REFERENCES]	= TILE_OP_UNSUPP,
+	[PERF_COUNT_HW_CACHE_MISSES]		= TILE_OP_UNSUPP,
+	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x16, /*
+					  MP_CONDITIONAL_BRANCH_ISSUED */
+	[PERF_COUNT_HW_BRANCH_MISSES]		= 0x14, /*
+					  MP_CONDITIONAL_BRANCH_MISSPREDICT */
+	[PERF_COUNT_HW_BUS_CYCLES]		= TILE_OP_UNSUPP,
+};
+#else
+/* TILEGx hardware events map */
+static const int tile_hw_event_map[] = {
+	[PERF_COUNT_HW_CPU_CYCLES]		= 0x181, /* ONE */
+	[PERF_COUNT_HW_INSTRUCTIONS]		= 0xdb, /* INSTRUCTION_BUNDLE */
+	[PERF_COUNT_HW_CACHE_REFERENCES]	= TILE_OP_UNSUPP,
+	[PERF_COUNT_HW_CACHE_MISSES]		= TILE_OP_UNSUPP,
+	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0xd9, /*
+						COND_BRANCH_PRED_CORRECT */
+	[PERF_COUNT_HW_BRANCH_MISSES]		= 0xda, /*
+						COND_BRANCH_PRED_INCORRECT */
+	[PERF_COUNT_HW_BUS_CYCLES]		= TILE_OP_UNSUPP,
+};
+#endif
+
+#define C(x) PERF_COUNT_HW_CACHE_##x
+
+/*
+ * Generalized hw caching related hw_event table, filled
+ * in on a per model basis. A value of -1 means
+ * 'not supported', any other value means the
+ * raw hw_event ID.
+ */
+#ifndef __tilegx__
+/* TILEPro hardware cache event map */
+static const int tile_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
+				     [PERF_COUNT_HW_CACHE_OP_MAX]
+				     [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+[C(L1D)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0x21, /* RD_MISS */
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0x22, /* WR_MISS */
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(L1I)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = 0x12, /* MP_ICACHE_HIT_ISSUED */
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(LL)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(DTLB)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = 0x1d, /* TLB_CNT */
+		[C(RESULT_MISS)] = 0x20, /* TLB_EXCEPTION */
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(ITLB)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = 0x13, /* MP_ITLB_HIT_ISSUED */
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(BPU)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+};
+#else
+/* TILEGx hardware events map */
+static const int tile_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
+				     [PERF_COUNT_HW_CACHE_OP_MAX]
+				     [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+[C(L1D)] = {
+	/*
+	 * Like some other architectures (e.g. ARM), the performance
+	 * counters don't differentiate between read and write
+	 * accesses/misses, so this isn't strictly correct, but it's the
+	 * best we can do. Writes and reads get combined.
+	 */
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0x44, /* RD_MISS */
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0x45, /* WR_MISS */
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(L1I)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(LL)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(DTLB)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = 0x40, /* TLB_CNT */
+		[C(RESULT_MISS)] = 0x43, /* TLB_EXCEPTION */
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = 0x40, /* TLB_CNT */
+		[C(RESULT_MISS)] = 0x43, /* TLB_EXCEPTION */
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(ITLB)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0xd4, /* ITLB_MISS_INT */
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = 0xd4, /* ITLB_MISS_INT */
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+[C(BPU)] = {
+	[C(OP_READ)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_WRITE)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+	[C(OP_PREFETCH)] = {
+		[C(RESULT_ACCESS)] = TILE_OP_UNSUPP,
+		[C(RESULT_MISS)] = TILE_OP_UNSUPP,
+	},
+},
+};
+#endif
+
+static atomic_t tile_active_events;
+static DEFINE_MUTEX(perf_intr_reserve_mutex);
+
+static int tile_map_hw_event(u64 config);
+static int tile_map_cache_event(u64 config);
+
+static int tile_pmu_handle_irq(struct pt_regs *regs, int fault);
+
+/*
+ * To avoid new_raw_count getting larger then pre_raw_count
+ * in tile_perf_event_update(), we limit the value of max_period to 2^31 - 1.
+ */
+static const struct tile_pmu tilepmu = {
+#ifndef __tilegx__
+	.name = "tilepro",
+#else
+	.name = "tilegx",
+#endif
+	.max_events = ARRAY_SIZE(tile_hw_event_map),
+	.map_hw_event = tile_map_hw_event,
+	.hw_events = tile_hw_event_map,
+	.map_cache_event = tile_map_cache_event,
+	.cache_events = &tile_cache_event_map,
+	.cntval_bits = 32,
+	.cntval_mask = (1ULL << 32) - 1,
+	.max_period = (1ULL << 31) - 1,
+	.num_counters = TILE_MAX_COUNTERS,
+	.num_base_counters = TILE_BASE_COUNTERS,
+};
+
+static const struct tile_pmu *tile_pmu __read_mostly;
+
+/*
+ * Check whether perf event is enabled.
+ */
+int tile_perf_enabled(void)
+{
+	return atomic_read(&tile_active_events) != 0;
+}
+
+/*
+ * Read Performance Counters.
+ */
+static inline u64 read_counter(int idx)
+{
+	u64 val = 0;
+
+	/* __insn_mfspr() only takes an immediate argument */
+	switch (idx) {
+	case PERF_COUNT_0_IDX:
+		val = __insn_mfspr(SPR_PERF_COUNT_0);
+		break;
+	case PERF_COUNT_1_IDX:
+		val = __insn_mfspr(SPR_PERF_COUNT_1);
+		break;
+	case AUX_PERF_COUNT_0_IDX:
+		val = __insn_mfspr(SPR_AUX_PERF_COUNT_0);
+		break;
+	case AUX_PERF_COUNT_1_IDX:
+		val = __insn_mfspr(SPR_AUX_PERF_COUNT_1);
+		break;
+	default:
+		WARN_ON_ONCE(idx > AUX_PERF_COUNT_1_IDX ||
+				idx < PERF_COUNT_0_IDX);
+	}
+
+	return val;
+}
+
+/*
+ * Write Performance Counters.
+ */
+static inline void write_counter(int idx, u64 value)
+{
+	/* __insn_mtspr() only takes an immediate argument */
+	switch (idx) {
+	case PERF_COUNT_0_IDX:
+		__insn_mtspr(SPR_PERF_COUNT_0, value);
+		break;
+	case PERF_COUNT_1_IDX:
+		__insn_mtspr(SPR_PERF_COUNT_1, value);
+		break;
+	case AUX_PERF_COUNT_0_IDX:
+		__insn_mtspr(SPR_AUX_PERF_COUNT_0, value);
+		break;
+	case AUX_PERF_COUNT_1_IDX:
+		__insn_mtspr(SPR_AUX_PERF_COUNT_1, value);
+		break;
+	default:
+		WARN_ON_ONCE(idx > AUX_PERF_COUNT_1_IDX ||
+				idx < PERF_COUNT_0_IDX);
+	}
+}
+
+/*
+ * Enable performance event by setting
+ * Performance Counter Control registers.
+ */
+static inline void tile_pmu_enable_event(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	unsigned long cfg, mask;
+	int shift, idx = hwc->idx;
+
+	/*
+	 * prevent early activation from tile_pmu_start() in hw_perf_enable
+	 */
+
+	if (WARN_ON_ONCE(idx == -1))
+		return;
+
+	if (idx < tile_pmu->num_base_counters)
+		cfg = __insn_mfspr(SPR_PERF_COUNT_CTL);
+	else
+		cfg = __insn_mfspr(SPR_AUX_PERF_COUNT_CTL);
+
+	switch (idx) {
+	case PERF_COUNT_0_IDX:
+	case AUX_PERF_COUNT_0_IDX:
+		mask = TILE_EVENT_MASK;
+		shift = 0;
+		break;
+	case PERF_COUNT_1_IDX:
+	case AUX_PERF_COUNT_1_IDX:
+		mask = TILE_EVENT_MASK << 16;
+		shift = 16;
+		break;
+	default:
+		WARN_ON_ONCE(idx < PERF_COUNT_0_IDX ||
+			idx > AUX_PERF_COUNT_1_IDX);
+		return;
+	}
+
+	/* Clear mask bits to enable the event. */
+	cfg &= ~mask;
+	cfg |= hwc->config << shift;
+
+	if (idx < tile_pmu->num_base_counters)
+		__insn_mtspr(SPR_PERF_COUNT_CTL, cfg);
+	else
+		__insn_mtspr(SPR_AUX_PERF_COUNT_CTL, cfg);
+}
+
+/*
+ * Disable performance event by clearing
+ * Performance Counter Control registers.
+ */
+static inline void tile_pmu_disable_event(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	unsigned long cfg, mask;
+	int idx = hwc->idx;
+
+	if (idx == -1)
+		return;
+
+	if (idx < tile_pmu->num_base_counters)
+		cfg = __insn_mfspr(SPR_PERF_COUNT_CTL);
+	else
+		cfg = __insn_mfspr(SPR_AUX_PERF_COUNT_CTL);
+
+	switch (idx) {
+	case PERF_COUNT_0_IDX:
+	case AUX_PERF_COUNT_0_IDX:
+		mask = TILE_PLM_MASK;
+		break;
+	case PERF_COUNT_1_IDX:
+	case AUX_PERF_COUNT_1_IDX:
+		mask = TILE_PLM_MASK << 16;
+		break;
+	default:
+		WARN_ON_ONCE(idx < PERF_COUNT_0_IDX ||
+			idx > AUX_PERF_COUNT_1_IDX);
+		return;
+	}
+
+	/* Set mask bits to disable the event. */
+	cfg |= mask;
+
+	if (idx < tile_pmu->num_base_counters)
+		__insn_mtspr(SPR_PERF_COUNT_CTL, cfg);
+	else
+		__insn_mtspr(SPR_AUX_PERF_COUNT_CTL, cfg);
+}
+
+/*
+ * Propagate event elapsed time into the generic event.
+ * Can only be executed on the CPU where the event is active.
+ * Returns the delta events processed.
+ */
+static u64 tile_perf_event_update(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int shift = 64 - tile_pmu->cntval_bits;
+	u64 prev_raw_count, new_raw_count;
+	u64 oldval;
+	int idx = hwc->idx;
+	u64 delta;
+
+	/*
+	 * Careful: an NMI might modify the previous event value.
+	 *
+	 * Our tactic to handle this is to first atomically read and
+	 * exchange a new raw count - then add that new-prev delta
+	 * count to the generic event atomically:
+	 */
+again:
+	prev_raw_count = local64_read(&hwc->prev_count);
+	new_raw_count = read_counter(idx);
+
+	oldval = local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+				 new_raw_count);
+	if (oldval != prev_raw_count)
+		goto again;
+
+	/*
+	 * Now we have the new raw value and have updated the prev
+	 * timestamp already. We can now calculate the elapsed delta
+	 * (event-)time and add that to the generic event.
+	 *
+	 * Careful, not all hw sign-extends above the physical width
+	 * of the count.
+	 */
+	delta = (new_raw_count << shift) - (prev_raw_count << shift);
+	delta >>= shift;
+
+	local64_add(delta, &event->count);
+	local64_sub(delta, &hwc->period_left);
+
+	return new_raw_count;
+}
+
+/*
+ * Set the next IRQ period, based on the hwc->period_left value.
+ * To be called with the event disabled in hw:
+ */
+static int tile_event_set_period(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int idx = hwc->idx;
+	s64 left = local64_read(&hwc->period_left);
+	s64 period = hwc->sample_period;
+	int ret = 0;
+
+	/*
+	 * If we are way outside a reasonable range then just skip forward:
+	 */
+	if (unlikely(left <= -period)) {
+		left = period;
+		local64_set(&hwc->period_left, left);
+		hwc->last_period = period;
+		ret = 1;
+	}
+
+	if (unlikely(left <= 0)) {
+		left += period;
+		local64_set(&hwc->period_left, left);
+		hwc->last_period = period;
+		ret = 1;
+	}
+	if (left > tile_pmu->max_period)
+		left = tile_pmu->max_period;
+
+	/*
+	 * The hw event starts counting from this event offset,
+	 * mark it to be able to extra future deltas:
+	 */
+	local64_set(&hwc->prev_count, (u64)-left);
+
+	write_counter(idx, (u64)(-left) & tile_pmu->cntval_mask);
+
+	perf_event_update_userpage(event);
+
+	return ret;
+}
+
+/*
+ * Stop the event but do not release the PMU counter
+ */
+static void tile_pmu_stop(struct perf_event *event, int flags)
+{
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	struct hw_perf_event *hwc = &event->hw;
+	int idx = hwc->idx;
+
+	if (__test_and_clear_bit(idx, cpuc->active_mask)) {
+		tile_pmu_disable_event(event);
+		cpuc->events[hwc->idx] = NULL;
+		WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+		hwc->state |= PERF_HES_STOPPED;
+	}
+
+	if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
+		/*
+		 * Drain the remaining delta count out of a event
+		 * that we are disabling:
+		 */
+		tile_perf_event_update(event);
+		hwc->state |= PERF_HES_UPTODATE;
+	}
+}
+
+/*
+ * Start an event (without re-assigning counter)
+ */
+static void tile_pmu_start(struct perf_event *event, int flags)
+{
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	int idx = event->hw.idx;
+
+	if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
+		return;
+
+	if (WARN_ON_ONCE(idx == -1))
+		return;
+
+	if (flags & PERF_EF_RELOAD) {
+		WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+		tile_event_set_period(event);
+	}
+
+	event->hw.state = 0;
+
+	cpuc->events[idx] = event;
+	__set_bit(idx, cpuc->active_mask);
+
+	unmask_pmc_interrupts();
+
+	tile_pmu_enable_event(event);
+
+	perf_event_update_userpage(event);
+}
+
+/*
+ * Add a single event to the PMU.
+ *
+ * The event is added to the group of enabled events
+ * but only if it can be scehduled with existing events.
+ */
+static int tile_pmu_add(struct perf_event *event, int flags)
+{
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	struct hw_perf_event *hwc;
+	unsigned long mask;
+	int b, max_cnt;
+
+	hwc = &event->hw;
+
+	/*
+	 * We are full.
+	 */
+	if (cpuc->n_events == tile_pmu->num_counters)
+		return -ENOSPC;
+
+	cpuc->event_list[cpuc->n_events] = event;
+	cpuc->n_events++;
+
+	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+	if (!(flags & PERF_EF_START))
+		hwc->state |= PERF_HES_ARCH;
+
+	/*
+	 * Find first empty counter.
+	 */
+	max_cnt = tile_pmu->num_counters;
+	mask = ~cpuc->used_mask;
+
+	/* Find next free counter. */
+	b = find_next_bit(&mask, max_cnt, 0);
+
+	/* Should not happen. */
+	if (WARN_ON_ONCE(b == max_cnt))
+		return -ENOSPC;
+
+	/*
+	 * Assign counter to event.
+	 */
+	event->hw.idx = b;
+	__set_bit(b, &cpuc->used_mask);
+
+	/*
+	 * Start if requested.
+	 */
+	if (flags & PERF_EF_START)
+		tile_pmu_start(event, PERF_EF_RELOAD);
+
+	return 0;
+}
+
+/*
+ * Delete a single event from the PMU.
+ *
+ * The event is deleted from the group of enabled events.
+ * If it is the last event, disable PMU interrupt.
+ */
+static void tile_pmu_del(struct perf_event *event, int flags)
+{
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	int i;
+
+	/*
+	 * Remove event from list, compact list if necessary.
+	 */
+	for (i = 0; i < cpuc->n_events; i++) {
+		if (cpuc->event_list[i] == event) {
+			while (++i < cpuc->n_events)
+				cpuc->event_list[i-1] = cpuc->event_list[i];
+			--cpuc->n_events;
+			cpuc->events[event->hw.idx] = NULL;
+			__clear_bit(event->hw.idx, &cpuc->used_mask);
+			tile_pmu_stop(event, PERF_EF_UPDATE);
+			break;
+		}
+	}
+	/*
+	 * If there are no events left, then mask PMU interrupt.
+	 */
+	if (cpuc->n_events == 0)
+		mask_pmc_interrupts();
+	perf_event_update_userpage(event);
+}
+
+/*
+ * Propagate event elapsed time into the event.
+ */
+static inline void tile_pmu_read(struct perf_event *event)
+{
+	tile_perf_event_update(event);
+}
+
+/*
+ * Map generic events to Tile PMU.
+ */
+static int tile_map_hw_event(u64 config)
+{
+	if (config >= tile_pmu->max_events)
+		return -EINVAL;
+	return tile_pmu->hw_events[config];
+}
+
+/*
+ * Map generic hardware cache events to Tile PMU.
+ */
+static int tile_map_cache_event(u64 config)
+{
+	unsigned int cache_type, cache_op, cache_result;
+	int code;
+
+	if (!tile_pmu->cache_events)
+		return -ENOENT;
+
+	cache_type = (config >>  0) & 0xff;
+	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
+		return -EINVAL;
+
+	cache_op = (config >>  8) & 0xff;
+	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
+		return -EINVAL;
+
+	cache_result = (config >> 16) & 0xff;
+	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+		return -EINVAL;
+
+	code = (*tile_pmu->cache_events)[cache_type][cache_op][cache_result];
+	if (code == TILE_OP_UNSUPP)
+		return -EINVAL;
+
+	return code;
+}
+
+static void tile_event_destroy(struct perf_event *event)
+{
+	if (atomic_dec_return(&tile_active_events) == 0)
+		release_pmc_hardware();
+}
+
+static int __tile_event_init(struct perf_event *event)
+{
+	struct perf_event_attr *attr = &event->attr;
+	struct hw_perf_event *hwc = &event->hw;
+	int code;
+
+	switch (attr->type) {
+	case PERF_TYPE_HARDWARE:
+		code = tile_pmu->map_hw_event(attr->config);
+		break;
+	case PERF_TYPE_HW_CACHE:
+		code = tile_pmu->map_cache_event(attr->config);
+		break;
+	case PERF_TYPE_RAW:
+		code = attr->config & TILE_EVENT_MASK;
+		break;
+	default:
+		/* Should not happen. */
+		return -EOPNOTSUPP;
+	}
+
+	if (code < 0)
+		return code;
+
+	hwc->config = code;
+	hwc->idx = -1;
+
+	if (attr->exclude_user)
+		hwc->config |= TILE_CTL_EXCL_USER;
+
+	if (attr->exclude_kernel)
+		hwc->config |= TILE_CTL_EXCL_KERNEL;
+
+	if (attr->exclude_hv)
+		hwc->config |= TILE_CTL_EXCL_HV;
+
+	if (!hwc->sample_period) {
+		hwc->sample_period = tile_pmu->max_period;
+		hwc->last_period = hwc->sample_period;
+		local64_set(&hwc->period_left, hwc->sample_period);
+	}
+	event->destroy = tile_event_destroy;
+	return 0;
+}
+
+static int tile_event_init(struct perf_event *event)
+{
+	int err = 0;
+	perf_irq_t old_irq_handler = NULL;
+
+	if (atomic_inc_return(&tile_active_events) == 1)
+		old_irq_handler = reserve_pmc_hardware(tile_pmu_handle_irq);
+
+	if (old_irq_handler) {
+		pr_warn("PMC hardware busy (reserved by oprofile)\n");
+
+		atomic_dec(&tile_active_events);
+		return -EBUSY;
+	}
+
+	switch (event->attr.type) {
+	case PERF_TYPE_RAW:
+	case PERF_TYPE_HARDWARE:
+	case PERF_TYPE_HW_CACHE:
+		break;
+
+	default:
+		return -ENOENT;
+	}
+
+	err = __tile_event_init(event);
+	if (err) {
+		if (event->destroy)
+			event->destroy(event);
+	}
+	return err;
+}
+
+static struct pmu tilera_pmu = {
+	.event_init	= tile_event_init,
+	.add		= tile_pmu_add,
+	.del		= tile_pmu_del,
+
+	.start		= tile_pmu_start,
+	.stop		= tile_pmu_stop,
+
+	.read		= tile_pmu_read,
+};
+
+/*
+ * PMU's IRQ handler, PMU has 2 interrupts, they share the same handler.
+ */
+int tile_pmu_handle_irq(struct pt_regs *regs, int fault)
+{
+	struct perf_sample_data data;
+	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+	struct perf_event *event;
+	struct hw_perf_event *hwc;
+	u64 val;
+	unsigned long status;
+	int bit;
+
+	__get_cpu_var(perf_irqs)++;
+
+	if (!atomic_read(&tile_active_events))
+		return 0;
+
+	status = pmc_get_overflow();
+	pmc_ack_overflow(status);
+
+	for_each_set_bit(bit, &status, tile_pmu->num_counters) {
+
+		event = cpuc->events[bit];
+
+		if (!event)
+			continue;
+
+		if (!test_bit(bit, cpuc->active_mask))
+			continue;
+
+		hwc = &event->hw;
+
+		val = tile_perf_event_update(event);
+		if (val & (1ULL << (tile_pmu->cntval_bits - 1)))
+			continue;
+
+		perf_sample_data_init(&data, 0, event->hw.last_period);
+		if (!tile_event_set_period(event))
+			continue;
+
+		if (perf_event_overflow(event, &data, regs))
+			tile_pmu_stop(event, 0);
+	}
+
+	return 0;
+}
+
+static bool __init supported_pmu(void)
+{
+	tile_pmu = &tilepmu;
+	return true;
+}
+
+int __init init_hw_perf_events(void)
+{
+	supported_pmu();
+	perf_pmu_register(&tilera_pmu, "cpu", PERF_TYPE_RAW);
+	return 0;
+}
+arch_initcall(init_hw_perf_events);
+
+/* Callchain handling code. */
+
+/*
+ * Tile specific backtracing code for perf_events.
+ */
+static inline void perf_callchain(struct perf_callchain_entry *entry,
+		    struct pt_regs *regs)
+{
+	struct KBacktraceIterator kbt;
+	unsigned int i;
+
+	/*
+	 * Get the address just after the "jalr" instruction that
+	 * jumps to the handler for a syscall.  When we find this
+	 * address in a backtrace, we silently ignore it, which gives
+	 * us a one-step backtrace connection from the sys_xxx()
+	 * function in the kernel to the xxx() function in libc.
+	 * Otherwise, we lose the ability to properly attribute time
+	 * from the libc calls to the kernel implementations, since
+	 * oprofile only considers PCs from backtraces a pair at a time.
+	 */
+	unsigned long handle_syscall_pc = handle_syscall_link_address();
+
+	KBacktraceIterator_init(&kbt, NULL, regs);
+	kbt.profile = 1;
+
+	/*
+	 * The sample for the pc is already recorded.  Now we are adding the
+	 * address of the callsites on the stack.  Our iterator starts
+	 * with the frame of the (already sampled) call site.  If our
+	 * iterator contained a "return address" field, we could have just
+	 * used it and wouldn't have needed to skip the first
+	 * frame.  That's in effect what the arm and x86 versions do.
+	 * Instead we peel off the first iteration to get the equivalent
+	 * behavior.
+	 */
+
+	if (KBacktraceIterator_end(&kbt))
+		return;
+	KBacktraceIterator_next(&kbt);
+
+	/*
+	 * Set stack depth to 16 for user and kernel space respectively, that
+	 * is, total 32 stack frames.
+	 */
+	for (i = 0; i < 16; ++i) {
+		unsigned long pc;
+		if (KBacktraceIterator_end(&kbt))
+			break;
+		pc = kbt.it.pc;
+		if (pc != handle_syscall_pc)
+			perf_callchain_store(entry, pc);
+		KBacktraceIterator_next(&kbt);
+	}
+}
+
+void perf_callchain_user(struct perf_callchain_entry *entry,
+		    struct pt_regs *regs)
+{
+	perf_callchain(entry, regs);
+}
+
+void perf_callchain_kernel(struct perf_callchain_entry *entry,
+		      struct pt_regs *regs)
+{
+	perf_callchain(entry, regs);
+}

arch/tile/kernel/pmc.c

+/*
+ * Copyright 2014 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   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, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/atomic.h>
+#include <linux/interrupt.h>
+
+#include <asm/processor.h>
+#include <asm/pmc.h>
+
+perf_irq_t perf_irq = NULL;
+int handle_perf_interrupt(struct pt_regs *regs, int fault)
+{
+	int retval;
+
+	if (!perf_irq)
+		panic("Unexpected PERF_COUNT interrupt %d\n", fault);
+
+	nmi_enter();
+	retval = perf_irq(regs, fault);
+	nmi_exit();
+	return retval;
+}
+
+/* Reserve PMC hardware if it is available. */
+perf_irq_t reserve_pmc_hardware(perf_irq_t new_perf_irq)
+{
+	return cmpxchg(&perf_irq, NULL, new_perf_irq);
+}
+EXPORT_SYMBOL(reserve_pmc_hardware);
+
+/* Release PMC hardware. */
+void release_pmc_hardware(void)
+{
+	perf_irq = NULL;
+}
+EXPORT_SYMBOL(release_pmc_hardware);
+
+
+/*
+ * Get current overflow status of each performance counter,
+ * and auxiliary performance counter.
+ */
+unsigned long
+pmc_get_overflow(void)
+{
+	unsigned long status;
+
+	/*
+	 * merge base+aux into a single vector
+	 */
+	status = __insn_mfspr(SPR_PERF_COUNT_STS);
+	status |= __insn_mfspr(SPR_AUX_PERF_COUNT_STS) << TILE_BASE_COUNTERS;
+	return status;
+}
+
+/*
+ * Clear the status bit for the corresponding counter, if written
+ * with a one.
+ */
+void
+pmc_ack_overflow(unsigned long status)
+{
+	/*
+	 * clear overflow status by writing ones
+	 */
+	__insn_mtspr(SPR_PERF_COUNT_STS, status);
+	__insn_mtspr(SPR_AUX_PERF_COUNT_STS, status >> TILE_BASE_COUNTERS);
+}
+
+/*
+ * The perf count interrupts are masked and unmasked explicitly,
+ * and only here.  The normal irq_enable() does not enable them,
+ * and irq_disable() does not disable them.  That lets these
+ * routines drive the perf count interrupts orthogonally.
+ *
+ * We also mask the perf count interrupts on entry to the perf count
+ * interrupt handler in assembly code, and by default unmask them
+ * again (with interrupt critical section protection) just before
+ * returning from the interrupt.  If the perf count handler returns
+ * a non-zero error code, then we don't re-enable them before returning.
+ *
+ * For Pro, we rely on both interrupts being in the same word to update
+ * them atomically so we never have one enabled and one disabled.
+ */
+
+#if CHIP_HAS_SPLIT_INTR_MASK()
+# if INT_PERF_COUNT < 32 || INT_AUX_PERF_COUNT < 32
+#  error Fix assumptions about which word PERF_COUNT interrupts are in
+# endif
+#endif
+
+static inline unsigned long long pmc_mask(void)
+{
+	unsigned long long mask = 1ULL << INT_PERF_COUNT;
+	mask |= 1ULL << INT_AUX_PERF_COUNT;
+	return mask;
+}
+
+void unmask_pmc_interrupts(void)
+{
+	interrupt_mask_reset_mask(pmc_mask());
+}
+
+void mask_pmc_interrupts(void)
+{
+	interrupt_mask_set_mask(pmc_mask());
+}

arch/tile/kernel/time.c

@@ -236,7 +236,15 @@ cycles_t ns2cycles(unsigned long nsecs)
 	 * clock frequency.
 	 */
 	struct clock_event_device *dev = &__raw_get_cpu_var(tile_timer);
-	return ((u64)nsecs * dev->mult) >> dev->shift;
+
+	/*
+	 * as in clocksource.h and x86's timer.h, we split the calculation
+	 * into 2 parts to avoid unecessary overflow of the intermediate
+	 * value. This will not lead to any loss of precision.
+	 */
+	u64 quot = (u64)nsecs >> dev->shift;
+	u64 rem  = (u64)nsecs & ((1ULL << dev->shift) - 1);
+	return quot * dev->mult + ((rem * dev->mult) >> dev->shift);
 }
 
 void update_vsyscall_tz(void)

arch/tile/kernel/vdso/Makefile

@@ -104,7 +104,7 @@ $(obj-vdso32:%=%): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
 $(obj-vdso32:%=%): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
 
 $(obj)/vgettimeofday32.o: $(obj)/vgettimeofday.c
-	$(call if_changed,cc_o_c)
+	$(call if_changed_rule,cc_o_c)
 
 $(obj)/vrt_sigreturn32.o: $(obj)/vrt_sigreturn.S
 	$(call if_changed,as_o_S)

tools/perf/config/Makefile.arch

@@ -5,7 +5,8 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
                                   -e s/arm.*/arm/ -e s/sa110/arm/ \
                                   -e s/s390x/s390/ -e s/parisc64/parisc/ \
                                   -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
-                                  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ )
+                                  -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
+                                  -e s/tile.*/tile/ )
 
 # Additional ARCH settings for x86
 ifeq ($(ARCH),i386)

tools/perf/perf.h

@@ -145,6 +145,14 @@
 #define CPUINFO_PROC	"core ID"
 #endif
 
+#ifdef __tile__
+#define mb()		asm volatile ("mf" ::: "memory")
+#define wmb()		asm volatile ("mf" ::: "memory")
+#define rmb()		asm volatile ("mf" ::: "memory")
+#define cpu_relax()	asm volatile ("mfspr zero, PASS" ::: "memory")
+#define CPUINFO_PROC    "model name"
+#endif
+
 #define barrier() asm volatile ("" ::: "memory")
 
 #ifndef cpu_relax