x86, bts, ptrace: move BTS buffer allocation from ds.c into ptrace.c (6abb11ae) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/x86/include/asm/ds.h

+4 −8

Original line number	Original line	Diff line number	Diff line
	@@ -7,13 +7,12 @@
	*		*
	* It manages:		* It manages:
	* - per-thread and per-cpu allocation of BTS and PEBS		* - per-thread and per-cpu allocation of BTS and PEBS
	* - buffer memory allocation (optional)		* - buffer overflow handling (to be done)
	* - buffer overflow handling
	* - buffer access		* - buffer access
	*		*
	* It assumes:		* It assumes:
	* - get_task_struct on all parameter tasks		* - get_task_struct on all traced tasks
	* - current is allowed to trace parameter tasks		* - current is allowed to trace tasks
	*		*
	*		*
	* Copyright (C) 2007-2008 Intel Corporation.		* Copyright (C) 2007-2008 Intel Corporation.
	@@ -54,8 +53,7 @@ typedef void (pebs_ovfl_callback_t)(struct pebs_tracer );
	* task: the task to request recording for;		* task: the task to request recording for;
	* NULL for per-cpu recording on the current cpu		* NULL for per-cpu recording on the current cpu
	* base: the base pointer for the (non-pageable) buffer;		* base: the base pointer for the (non-pageable) buffer;
	* NULL if buffer allocation requested		* size: the size of the provided buffer in bytes
	* size: the size of the requested or provided buffer in bytes
	* ovfl: pointer to a function to be called on buffer overflow;		* ovfl: pointer to a function to be called on buffer overflow;
	* NULL if cyclic buffer requested		* NULL if cyclic buffer requested
	* th: the interrupt threshold in records from the end of the buffer;		* th: the interrupt threshold in records from the end of the buffer;
	@@ -72,8 +70,6 @@ extern struct pebs_tracer ds_request_pebs(struct task_struct task,
	/*		/*
	* Release BTS or PEBS resources		* Release BTS or PEBS resources
	*		*
	* Frees buffers allocated on ds_request.
	*
	* Returns 0 on success; -Eerrno otherwise		* Returns 0 on success; -Eerrno otherwise
	*		*
	* tracer: the tracer handle returned from ds_request_~()		* tracer: the tracer handle returned from ds_request_~()

arch/x86/kernel/ds.c

+14 −78

Original line number	Original line	Diff line number	Diff line
	@@ -7,13 +7,12 @@
	*		*
	* It manages:		* It manages:
	* - per-thread and per-cpu allocation of BTS and PEBS		* - per-thread and per-cpu allocation of BTS and PEBS
	* - buffer memory allocation (optional)		* - buffer overflow handling (to be done)
	* - buffer overflow handling
	* - buffer access		* - buffer access
	*		*
	* It assumes:		* It assumes:
	* - get_task_struct on all parameter tasks		* - get_task_struct on all traced tasks
	* - current is allowed to trace parameter tasks		* - current is allowed to trace tasks
	*		*
	*		*
	* Copyright (C) 2007-2008 Intel Corporation.		* Copyright (C) 2007-2008 Intel Corporation.
	@@ -57,8 +56,6 @@ struct ds_tracer {
	/* the buffer provided on ds_request() and its size in bytes */		/* the buffer provided on ds_request() and its size in bytes */
	void *buffer;		void *buffer;
	size_t size;		size_t size;
	/* the number of allocated pages for on-request allocated buffers */
	unsigned int pages;
	};		};

	struct bts_tracer {		struct bts_tracer {
	@@ -141,8 +138,7 @@ static inline void ds_set(unsigned char *base, enum ds_qualifier qual,


	/*		/*
	* Locking is done only for allocating BTS or PEBS resources and for		* Locking is done only for allocating BTS or PEBS resources.
	* guarding context and buffer memory allocation.
	*/		*/
	static spinlock_t ds_lock = __SPIN_LOCK_UNLOCKED(ds_lock);		static spinlock_t ds_lock = __SPIN_LOCK_UNLOCKED(ds_lock);

	@@ -292,50 +288,6 @@ static void ds_overflow(struct ds_context *context, enum ds_qualifier qual)
	}		}


	/*
	* Allocate a non-pageable buffer of the parameter size.
	* Checks the memory and the locked memory rlimit.
	*
	* Returns the buffer, if successful;
	* NULL, if out of memory or rlimit exceeded.
	*
	* size: the requested buffer size in bytes
	* pages (out): if not NULL, contains the number of pages reserved
	*/
	static inline void ds_allocate_buffer(size_t size, unsigned int pages)
	{
	unsigned long rlim, vm, pgsz;
	void *buffer = NULL;

	pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;

	down_write(&current->mm->mmap_sem);

	rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
	vm = current->mm->total_vm + pgsz;
	if (rlim < vm)
	goto out;

	rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
	vm = current->mm->locked_vm + pgsz;
	if (rlim < vm)
	goto out;

	buffer = kzalloc(size, GFP_KERNEL);
	if (!buffer)
	goto out;

	current->mm->total_vm += pgsz;
	current->mm->locked_vm += pgsz;

	if (pages)
	*pages = pgsz;

	out:
	up_write(&current->mm->mmap_sem);
	return buffer;
	}

	static void ds_install_ds_config(struct ds_context *context,		static void ds_install_ds_config(struct ds_context *context,
	enum ds_qualifier qual,		enum ds_qualifier qual,
	void *base, size_t size, size_t ith)		void *base, size_t size, size_t ith)
	@@ -382,6 +334,10 @@ static int ds_request(struct ds_tracer *tracer, enum ds_qualifier qual,
	if (!ds_cfg.sizeof_ds)		if (!ds_cfg.sizeof_ds)
	goto out;		goto out;

			error = -EINVAL;
			if (!base)
			goto out;

	/* we require some space to do alignment adjustments below */		/* we require some space to do alignment adjustments below */
	error = -EINVAL;		error = -EINVAL;
	if (size < (DS_ALIGNMENT + ds_cfg.sizeof_rec[qual]))		if (size < (DS_ALIGNMENT + ds_cfg.sizeof_rec[qual]))
	@@ -395,13 +351,6 @@ static int ds_request(struct ds_tracer *tracer, enum ds_qualifier qual,
	goto out;		goto out;
	}		}

	error = -ENOMEM;
	if (!base) {
	base = ds_allocate_buffer(size, &tracer->pages);
	if (!base)
	goto out;
	}

	tracer->buffer = base;		tracer->buffer = base;
	tracer->size = size;		tracer->size = size;

	@@ -466,7 +415,7 @@ struct bts_tracer ds_request_bts(struct task_struct task,
	return tracer;		return tracer;

	out_tracer:		out_tracer:
	(void)ds_release_bts(tracer);		kfree(tracer);
	out:		out:
	return ERR_PTR(error);		return ERR_PTR(error);
	}		}
	@@ -496,14 +445,13 @@ struct pebs_tracer ds_request_pebs(struct task_struct task,
	return tracer;		return tracer;

	out_tracer:		out_tracer:
	(void)ds_release_pebs(tracer);		kfree(tracer);
	out:		out:
	return ERR_PTR(error);		return ERR_PTR(error);
	}		}

	static void ds_release(struct ds_tracer *tracer, enum ds_qualifier qual)		static void ds_release(struct ds_tracer *tracer, enum ds_qualifier qual)
	{		{
	if (tracer->context) {
	BUG_ON(tracer->context->owner[qual] != tracer);		BUG_ON(tracer->context->owner[qual] != tracer);
	tracer->context->owner[qual] = NULL;		tracer->context->owner[qual] = NULL;

	@@ -511,18 +459,6 @@ static void ds_release(struct ds_tracer *tracer, enum ds_qualifier qual)
	ds_put_context(tracer->context);		ds_put_context(tracer->context);
	}		}

	if (tracer->pages) {
	kfree(tracer->buffer);

	down_write(&current->mm->mmap_sem);

	current->mm->total_vm -= tracer->pages;
	current->mm->locked_vm -= tracer->pages;

	up_write(&current->mm->mmap_sem);
	}
	}

	int ds_release_bts(struct bts_tracer *tracer)		int ds_release_bts(struct bts_tracer *tracer)
	{		{
	if (!tracer)		if (!tracer)

arch/x86/kernel/ptrace.c

+20 −2

Original line number	Original line	Diff line number	Diff line
	@@ -758,6 +758,10 @@ static int ptrace_bts_config(struct task_struct *child,
	bts_ovfl_callback_t ovfl = NULL;		bts_ovfl_callback_t ovfl = NULL;
	unsigned int sig = 0;		unsigned int sig = 0;

			error = -EINVAL;
			if (cfg.size < (10 * bts_cfg.sizeof_bts))
			goto errout;

	if (cfg.flags & PTRACE_BTS_O_SIGNAL) {		if (cfg.flags & PTRACE_BTS_O_SIGNAL) {
	if (!cfg.signal)		if (!cfg.signal)
	goto errout;		goto errout;
	@@ -768,14 +772,26 @@ static int ptrace_bts_config(struct task_struct *child,
	sig = cfg.signal;		sig = cfg.signal;
	}		}

	if (child->bts)		if (child->bts) {
	(void)ds_release_bts(child->bts);		(void)ds_release_bts(child->bts);
			kfree(child->bts_buffer);

			child->bts = NULL;
			child->bts_buffer = NULL;
			}

			error = -ENOMEM;
			child->bts_buffer = kzalloc(cfg.size, GFP_KERNEL);
			if (!child->bts_buffer)
			goto errout;

	child->bts = ds_request_bts(child, /* base = */ NULL, cfg.size,		child->bts = ds_request_bts(child, child->bts_buffer, cfg.size,
	ovfl, /* th = */ (size_t)-1);		ovfl, /* th = */ (size_t)-1);
	if (IS_ERR(child->bts)) {		if (IS_ERR(child->bts)) {
	error = PTR_ERR(child->bts);		error = PTR_ERR(child->bts);
			kfree(child->bts_buffer);
	child->bts = NULL;		child->bts = NULL;
			child->bts_buffer = NULL;
	goto errout;		goto errout;
	}		}

	@@ -972,6 +988,8 @@ void ptrace_disable(struct task_struct *child)
	#ifdef CONFIG_X86_PTRACE_BTS		#ifdef CONFIG_X86_PTRACE_BTS
	if (child->bts) {		if (child->bts) {
	(void)ds_release_bts(child->bts);		(void)ds_release_bts(child->bts);
			kfree(child->bts_buffer);
			child->bts_buffer = NULL;

	child->thread.debugctlmsr &= ~bts_cfg.debugctl_mask;		child->thread.debugctlmsr &= ~bts_cfg.debugctl_mask;
	if (!child->thread.debugctlmsr)		if (!child->thread.debugctlmsr)

include/linux/sched.h

+4 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1168,6 +1168,10 @@ struct task_struct {
	* This field actually belongs to the ptracer task.		* This field actually belongs to the ptracer task.
	*/		*/
	struct bts_tracer *bts;		struct bts_tracer *bts;
			/*
			* The buffer to hold the BTS data.
			*/
			void *bts_buffer;
	#endif /* CONFIG_X86_PTRACE_BTS */		#endif /* CONFIG_X86_PTRACE_BTS */

	/* PID/PID hash table linkage. */		/* PID/PID hash table linkage. */