From 8e3441ebab48c3537b1a9ae06fb7616a3332bd35 Mon Sep 17 00:00:00 2001 From: Zhigang Lu Date: Mon, 27 Jan 2014 15:11:07 +0800 Subject: [PATCH] tile: Add support for handling PMC hardware The PMC module is used by perf_events, oprofile and watchdogs. Signed-off-by: Zhigang Lu Signed-off-by: Chris Metcalf --- arch/tile/Kconfig | 4 ++ arch/tile/include/asm/pmc.h | 64 ++++++++++++++++++ arch/tile/kernel/Makefile | 1 + arch/tile/kernel/intvec_32.S | 13 ++-- arch/tile/kernel/intvec_64.S | 13 ++-- arch/tile/kernel/pmc.c | 121 +++++++++++++++++++++++++++++++++++ 6 files changed, 204 insertions(+), 12 deletions(-) create mode 100644 arch/tile/include/asm/pmc.h create mode 100644 arch/tile/kernel/pmc.c diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index b3692ce78f90..3067b15e80d6 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -66,6 +66,10 @@ 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 diff --git a/arch/tile/include/asm/pmc.h b/arch/tile/include/asm/pmc.h new file mode 100644 index 000000000000..7ae3956d9008 --- /dev/null +++ b/arch/tile/include/asm/pmc.h @@ -0,0 +1,64 @@ +/* + * 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 + +#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 */ diff --git a/arch/tile/kernel/Makefile b/arch/tile/kernel/Makefile index 27a2bf39dae8..71d835365c73 100644 --- a/arch/tile/kernel/Makefile +++ b/arch/tile/kernel/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_PCI) += pci_gx.o else obj-$(CONFIG_PCI) += pci.o endif +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 diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S index 2cbe6d5dd6b0..605ffbda44ff 100644 --- a/arch/tile/kernel/intvec_32.S +++ b/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 */ @@ -1835,8 +1835,9 @@ 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 +1878,7 @@ 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 +1903,7 @@ 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 diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S index b8fc497f2437..8f892a58afd4 100644 --- a/arch/tile/kernel/intvec_64.S +++ b/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 @@ -1491,8 +1491,9 @@ 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 +1541,9 @@ 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 diff --git a/arch/tile/kernel/pmc.c b/arch/tile/kernel/pmc.c new file mode 100644 index 000000000000..db62cc34b955 --- /dev/null +++ b/arch/tile/kernel/pmc.c @@ -0,0 +1,121 @@ +/* + * 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 +#include +#include +#include +#include + +#include +#include + +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()); +} -- 2.20.1