x86, perf, bts, mm: Delete the never used BTS-ptrace code (faa4602e) · Commits · 戴 / test

arch/x86/Kconfig.cpu

+0 −20

Original line number	Diff line number	Diff line
		@@ -502,23 +502,3 @@ config CPU_SUP_UMC_32
		CPU might render the kernel unbootable.

		If unsure, say N.

		config X86_DS
		def_bool X86_PTRACE_BTS
		depends on X86_DEBUGCTLMSR
		select HAVE_HW_BRANCH_TRACER

		config X86_PTRACE_BTS
		bool "Branch Trace Store"
		default y
		depends on X86_DEBUGCTLMSR
		depends on BROKEN
		---help---
		This adds a ptrace interface to the hardware's branch trace store.

		Debuggers may use it to collect an execution trace of the debugged
		application in order to answer the question 'how did I get here?'.
		Debuggers may trace user mode as well as kernel mode.

		Say Y unless there is no application development on this machine
		and you want to save a small amount of code size.

arch/x86/Kconfig.debug

+0 −9

Original line number	Diff line number	Diff line
		@@ -174,15 +174,6 @@ config IOMMU_LEAK
		Add a simple leak tracer to the IOMMU code. This is useful when you
		are debugging a buggy device driver that leaks IOMMU mappings.

		config X86_DS_SELFTEST
		bool "DS selftest"
		default y
		depends on DEBUG_KERNEL
		depends on X86_DS
		---help---
		Perform Debug Store selftests at boot time.
		If in doubt, say "N".

		config HAVE_MMIOTRACE_SUPPORT
		def_bool y

arch/x86/include/asm/ds.h

deleted100644 → 0

+0 −302

Original line number	Diff line number	Diff line
		/*
		* Debug Store (DS) support
		*
		* This provides a low-level interface to the hardware's Debug Store
		* feature that is used for branch trace store (BTS) and
		* precise-event based sampling (PEBS).
		*
		* It manages:
		* - DS and BTS hardware configuration
		* - buffer overflow handling (to be done)
		* - buffer access
		*
		* It does not do:
		* - security checking (is the caller allowed to trace the task)
		* - buffer allocation (memory accounting)
		*
		*
		* Copyright (C) 2007-2009 Intel Corporation.
		* Markus Metzger <markus.t.metzger@intel.com>, 2007-2009
		*/

		#ifndef _ASM_X86_DS_H
		#define _ASM_X86_DS_H


		#include <linux/types.h>
		#include <linux/init.h>
		#include <linux/err.h>


		#ifdef CONFIG_X86_DS

		struct task_struct;
		struct ds_context;
		struct ds_tracer;
		struct bts_tracer;
		struct pebs_tracer;

		typedef void (bts_ovfl_callback_t)(struct bts_tracer );
		typedef void (pebs_ovfl_callback_t)(struct pebs_tracer );


		/*
		* A list of features plus corresponding macros to talk about them in
		* the ds_request function's flags parameter.
		*
		* We use the enum to index an array of corresponding control bits;
		* we use the macro to index a flags bit-vector.
		*/
		enum ds_feature {
		dsf_bts = 0,
		dsf_bts_kernel,
		#define BTS_KERNEL (1 << dsf_bts_kernel)
		/* trace kernel-mode branches */

		dsf_bts_user,
		#define BTS_USER (1 << dsf_bts_user)
		/* trace user-mode branches */

		dsf_bts_overflow,
		dsf_bts_max,
		dsf_pebs = dsf_bts_max,

		dsf_pebs_max,
		dsf_ctl_max = dsf_pebs_max,
		dsf_bts_timestamps = dsf_ctl_max,
		#define BTS_TIMESTAMPS (1 << dsf_bts_timestamps)
		/* add timestamps into BTS trace */

		#define BTS_USER_FLAGS (BTS_KERNEL \| BTS_USER \| BTS_TIMESTAMPS)
		};


		/*
		* Request BTS or PEBS
		*
		* Due to alignement constraints, the actual buffer may be slightly
		* smaller than the requested or provided buffer.
		*
		* Returns a pointer to a tracer structure on success, or
		* ERR_PTR(errcode) on failure.
		*
		* The interrupt threshold is independent from the overflow callback
		* to allow users to use their own overflow interrupt handling mechanism.
		*
		* The function might sleep.
		*
		* task: the task to request recording for
		* cpu: the cpu to request recording for
		* base: the base pointer for the (non-pageable) buffer;
		* size: the size of the provided buffer in bytes
		* ovfl: pointer to a function to be called on buffer overflow;
		* NULL if cyclic buffer requested
		* th: the interrupt threshold in records from the end of the buffer;
		* -1 if no interrupt threshold is requested.
		* flags: a bit-mask of the above flags
		*/
		extern struct bts_tracer ds_request_bts_task(struct task_struct task,
		void *base, size_t size,
		bts_ovfl_callback_t ovfl,
		size_t th, unsigned int flags);
		extern struct bts_tracer ds_request_bts_cpu(int cpu, void base, size_t size,
		bts_ovfl_callback_t ovfl,
		size_t th, unsigned int flags);
		extern struct pebs_tracer ds_request_pebs_task(struct task_struct task,
		void *base, size_t size,
		pebs_ovfl_callback_t ovfl,
		size_t th, unsigned int flags);
		extern struct pebs_tracer *ds_request_pebs_cpu(int cpu,
		void *base, size_t size,
		pebs_ovfl_callback_t ovfl,
		size_t th, unsigned int flags);

		/*
		* Release BTS or PEBS resources
		* Suspend and resume BTS or PEBS tracing
		*
		* Must be called with irq's enabled.
		*
		* tracer: the tracer handle returned from ds_request_~()
		*/
		extern void ds_release_bts(struct bts_tracer *tracer);
		extern void ds_suspend_bts(struct bts_tracer *tracer);
		extern void ds_resume_bts(struct bts_tracer *tracer);
		extern void ds_release_pebs(struct pebs_tracer *tracer);
		extern void ds_suspend_pebs(struct pebs_tracer *tracer);
		extern void ds_resume_pebs(struct pebs_tracer *tracer);

		/*
		* Release BTS or PEBS resources
		* Suspend and resume BTS or PEBS tracing
		*
		* Cpu tracers must call this on the traced cpu.
		* Task tracers must call ds_release_~_noirq() for themselves.
		*
		* May be called with irq's disabled.
		*
		* Returns 0 if successful;
		* -EPERM if the cpu tracer does not trace the current cpu.
		* -EPERM if the task tracer does not trace itself.
		*
		* tracer: the tracer handle returned from ds_request_~()
		*/
		extern int ds_release_bts_noirq(struct bts_tracer *tracer);
		extern int ds_suspend_bts_noirq(struct bts_tracer *tracer);
		extern int ds_resume_bts_noirq(struct bts_tracer *tracer);
		extern int ds_release_pebs_noirq(struct pebs_tracer *tracer);
		extern int ds_suspend_pebs_noirq(struct pebs_tracer *tracer);
		extern int ds_resume_pebs_noirq(struct pebs_tracer *tracer);


		/*
		* The raw DS buffer state as it is used for BTS and PEBS recording.
		*
		* This is the low-level, arch-dependent interface for working
		* directly on the raw trace data.
		*/
		struct ds_trace {
		/* the number of bts/pebs records */
		size_t n;
		/* the size of a bts/pebs record in bytes */
		size_t size;
		/* pointers into the raw buffer:
		- to the first entry */
		void *begin;
		/* - one beyond the last entry */
		void *end;
		/* - one beyond the newest entry */
		void *top;
		/* - the interrupt threshold */
		void *ith;
		/* flags given on ds_request() */
		unsigned int flags;
		};

		/*
		* An arch-independent view on branch trace data.
		*/
		enum bts_qualifier {
		bts_invalid,
		#define BTS_INVALID bts_invalid

		bts_branch,
		#define BTS_BRANCH bts_branch

		bts_task_arrives,
		#define BTS_TASK_ARRIVES bts_task_arrives

		bts_task_departs,
		#define BTS_TASK_DEPARTS bts_task_departs

		bts_qual_bit_size = 4,
		bts_qual_max = (1 << bts_qual_bit_size),
		};

		struct bts_struct {
		__u64 qualifier;
		union {
		/* BTS_BRANCH */
		struct {
		__u64 from;
		__u64 to;
		} lbr;
		/* BTS_TASK_ARRIVES or BTS_TASK_DEPARTS */
		struct {
		__u64 clock;
		pid_t pid;
		} event;
		} variant;
		};


		/*
		* The BTS state.
		*
		* This gives access to the raw DS state and adds functions to provide
		* an arch-independent view of the BTS data.
		*/
		struct bts_trace {
		struct ds_trace ds;

		int (read)(struct bts_tracer tracer, const void *at,
		struct bts_struct *out);
		int (write)(struct bts_tracer tracer, const struct bts_struct *in);
		};


		/*
		* The PEBS state.
		*
		* This gives access to the raw DS state and the PEBS-specific counter
		* reset value.
		*/
		struct pebs_trace {
		struct ds_trace ds;

		/* the number of valid counters in the below array */
		unsigned int counters;

		#define MAX_PEBS_COUNTERS 4
		/* the counter reset value */
		unsigned long long counter_reset[MAX_PEBS_COUNTERS];
		};


		/*
		* Read the BTS or PEBS trace.
		*
		* Returns a view on the trace collected for the parameter tracer.
		*
		* The view remains valid as long as the traced task is not running or
		* the tracer is suspended.
		* Writes into the trace buffer are not reflected.
		*
		* tracer: the tracer handle returned from ds_request_~()
		*/
		extern const struct bts_trace ds_read_bts(struct bts_tracer tracer);
		extern const struct pebs_trace ds_read_pebs(struct pebs_tracer tracer);


		/*
		* Reset the write pointer of the BTS/PEBS buffer.
		*
		* Returns 0 on success; -Eerrno on error
		*
		* tracer: the tracer handle returned from ds_request_~()
		*/
		extern int ds_reset_bts(struct bts_tracer *tracer);
		extern int ds_reset_pebs(struct pebs_tracer *tracer);

		/*
		* Set the PEBS counter reset value.
		*
		* Returns 0 on success; -Eerrno on error
		*
		* tracer: the tracer handle returned from ds_request_pebs()
		* counter: the index of the counter
		* value: the new counter reset value
		*/
		extern int ds_set_pebs_reset(struct pebs_tracer *tracer,
		unsigned int counter, u64 value);

		/*
		* Initialization
		*/
		struct cpuinfo_x86;
		extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *);

		/*
		* Context switch work
		*/
		extern void ds_switch_to(struct task_struct prev, struct task_struct next);

		#else /* CONFIG_X86_DS */

		struct cpuinfo_x86;
		static inline void __cpuinit ds_init_intel(struct cpuinfo_x86 *ignored) {}
		static inline void ds_switch_to(struct task_struct *prev,
		struct task_struct *next) {}

		#endif /* CONFIG_X86_DS */
		#endif /* _ASM_X86_DS_H */

arch/x86/include/asm/processor.h

+1 −32

Original line number	Diff line number	Diff line
		@@ -21,7 +21,6 @@ struct mm_struct;
		#include <asm/msr.h>
		#include <asm/desc_defs.h>
		#include <asm/nops.h>
		#include <asm/ds.h>

		#include <linux/personality.h>
		#include <linux/cpumask.h>
		@@ -29,6 +28,7 @@ struct mm_struct;
		#include <linux/threads.h>
		#include <linux/math64.h>
		#include <linux/init.h>
		#include <linux/err.h>

		#define HBP_NUM 4
		/*
		@@ -473,10 +473,6 @@ struct thread_struct {
		unsigned long iopl;
		/* Max allowed port in the bitmap, in bytes: */
		unsigned io_bitmap_max;
		/* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */
		unsigned long debugctlmsr;
		/* Debug Store context; see asm/ds.h */
		struct ds_context *ds_ctx;
		};

		static inline unsigned long native_get_debugreg(int regno)
		@@ -814,21 +810,6 @@ static inline unsigned long get_debugctlmsr(void)
		return debugctlmsr;
		}

		static inline unsigned long get_debugctlmsr_on_cpu(int cpu)
		{
		u64 debugctlmsr = 0;
		u32 val1, val2;

		#ifndef CONFIG_X86_DEBUGCTLMSR
		if (boot_cpu_data.x86 < 6)
		return 0;
		#endif
		rdmsr_on_cpu(cpu, MSR_IA32_DEBUGCTLMSR, &val1, &val2);
		debugctlmsr = val1 \| ((u64)val2 << 32);

		return debugctlmsr;
		}

		static inline void update_debugctlmsr(unsigned long debugctlmsr)
		{
		#ifndef CONFIG_X86_DEBUGCTLMSR
		@@ -838,18 +819,6 @@ static inline void update_debugctlmsr(unsigned long debugctlmsr)
		wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
		}

		static inline void update_debugctlmsr_on_cpu(int cpu,
		unsigned long debugctlmsr)
		{
		#ifndef CONFIG_X86_DEBUGCTLMSR
		if (boot_cpu_data.x86 < 6)
		return;
		#endif
		wrmsr_on_cpu(cpu, MSR_IA32_DEBUGCTLMSR,
		(u32)((u64)debugctlmsr),
		(u32)((u64)debugctlmsr >> 32));
		}

		/*
		* from system description table in BIOS. Mostly for MCA use, but
		* others may find it useful:

arch/x86/include/asm/ptrace-abi.h

+1 −56

Original line number	Diff line number	Diff line
		@@ -82,61 +82,6 @@

		#ifndef __ASSEMBLY__
		#include <linux/types.h>

		/* configuration/status structure used in PTRACE_BTS_CONFIG and
		PTRACE_BTS_STATUS commands.
		*/
		struct ptrace_bts_config {
		/* requested or actual size of BTS buffer in bytes */
		__u32 size;
		/* bitmask of below flags */
		__u32 flags;
		/* buffer overflow signal */
		__u32 signal;
		/* actual size of bts_struct in bytes */
		__u32 bts_size;
		};
		#endif /* __ASSEMBLY__ */

		#define PTRACE_BTS_O_TRACE 0x1 /* branch trace */
		#define PTRACE_BTS_O_SCHED 0x2 /* scheduling events w/ jiffies */
		#define PTRACE_BTS_O_SIGNAL 0x4 /* send SIG<signal> on buffer overflow
		instead of wrapping around */
		#define PTRACE_BTS_O_ALLOC 0x8 /* (re)allocate buffer */

		#define PTRACE_BTS_CONFIG 40
		/* Configure branch trace recording.
		ADDR points to a struct ptrace_bts_config.
		DATA gives the size of that buffer.
		A new buffer is allocated, if requested in the flags.
		An overflow signal may only be requested for new buffers.
		Returns the number of bytes read.
		*/
		#define PTRACE_BTS_STATUS 41
		/* Return the current configuration in a struct ptrace_bts_config
		pointed to by ADDR; DATA gives the size of that buffer.
		Returns the number of bytes written.
		*/
		#define PTRACE_BTS_SIZE 42
		/* Return the number of available BTS records for draining.
		DATA and ADDR are ignored.
		*/
		#define PTRACE_BTS_GET 43
		/* Get a single BTS record.
		DATA defines the index into the BTS array, where 0 is the newest
		entry, and higher indices refer to older entries.
		ADDR is pointing to struct bts_struct (see asm/ds.h).
		*/
		#define PTRACE_BTS_CLEAR 44
		/* Clear the BTS buffer.
		DATA and ADDR are ignored.
		*/
		#define PTRACE_BTS_DRAIN 45
		/* Read all available BTS records and clear the buffer.
		ADDR points to an array of struct bts_struct.
		DATA gives the size of that buffer.
		BTS records are read from oldest to newest.
		Returns number of BTS records drained.
		*/
		#endif

		#endif /* _ASM_X86_PTRACE_ABI_H */

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