#include <linux/types.h>
#include <linux/init.h>
+#include <linux/err.h>
#ifdef CONFIG_X86_DS
struct task_struct;
+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 *);
/*
* Request BTS or PEBS
* Due to alignement constraints, the actual buffer may be slightly
* smaller than the requested or provided buffer.
*
- * Returns 0 on success; -Eerrno otherwise
+ * 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.
*
* task: the task to request recording for;
* NULL for per-cpu recording on the current cpu
* base: the base pointer for the (non-pageable) buffer;
* NULL if buffer allocation requested
- * size: the size of the requested or provided buffer
+ * size: the size of the requested or 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.
*/
-typedef void (*ds_ovfl_callback_t)(struct task_struct *);
-extern int ds_request_bts(struct task_struct *task, void *base, size_t size,
- ds_ovfl_callback_t ovfl);
-extern int ds_request_pebs(struct task_struct *task, void *base, size_t size,
- ds_ovfl_callback_t ovfl);
+extern struct bts_tracer *ds_request_bts(struct task_struct *task,
+ void *base, size_t size,
+ bts_ovfl_callback_t ovfl, size_t th);
+extern struct pebs_tracer *ds_request_pebs(struct task_struct *task,
+ void *base, size_t size,
+ pebs_ovfl_callback_t ovfl,
+ size_t th);
/*
* Release BTS or PEBS resources
*
* Returns 0 on success; -Eerrno otherwise
*
- * task: the task to release resources for;
- * NULL to release resources for the current cpu
+ * tracer: the tracer handle returned from ds_request_~()
*/
-extern int ds_release_bts(struct task_struct *task);
-extern int ds_release_pebs(struct task_struct *task);
+extern int ds_release_bts(struct bts_tracer *tracer);
+extern int ds_release_pebs(struct pebs_tracer *tracer);
/*
- * Return the (array) index of the write pointer.
+ * Get the (array) index of the write pointer.
* (assuming an array of BTS/PEBS records)
*
- * Returns -Eerrno on error
+ * Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
- * pos (out): if not NULL, will hold the result
+ * tracer: the tracer handle returned from ds_request_~()
+ * pos (out): will hold the result
*/
-extern int ds_get_bts_index(struct task_struct *task, size_t *pos);
-extern int ds_get_pebs_index(struct task_struct *task, size_t *pos);
+extern int ds_get_bts_index(struct bts_tracer *tracer, size_t *pos);
+extern int ds_get_pebs_index(struct pebs_tracer *tracer, size_t *pos);
/*
- * Return the (array) index one record beyond the end of the array.
+ * Get the (array) index one record beyond the end of the array.
* (assuming an array of BTS/PEBS records)
*
- * Returns -Eerrno on error
+ * Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
- * pos (out): if not NULL, will hold the result
+ * tracer: the tracer handle returned from ds_request_~()
+ * pos (out): will hold the result
*/
-extern int ds_get_bts_end(struct task_struct *task, size_t *pos);
-extern int ds_get_pebs_end(struct task_struct *task, size_t *pos);
+extern int ds_get_bts_end(struct bts_tracer *tracer, size_t *pos);
+extern int ds_get_pebs_end(struct pebs_tracer *tracer, size_t *pos);
/*
* Provide a pointer to the BTS/PEBS record at parameter index.
*
* Returns the size of a single record on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_~()
* index: the index of the requested record
* record (out): pointer to the requested record
*/
-extern int ds_access_bts(struct task_struct *task,
+extern int ds_access_bts(struct bts_tracer *tracer,
size_t index, const void **record);
-extern int ds_access_pebs(struct task_struct *task,
+extern int ds_access_pebs(struct pebs_tracer *tracer,
size_t index, const void **record);
/*
*
* Returns the number of bytes written or -Eerrno.
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_~()
* buffer: the buffer to write
* size: the size of the buffer
*/
-extern int ds_write_bts(struct task_struct *task,
+extern int ds_write_bts(struct bts_tracer *tracer,
const void *buffer, size_t size);
-extern int ds_write_pebs(struct task_struct *task,
+extern int ds_write_pebs(struct pebs_tracer *tracer,
const void *buffer, size_t size);
-/*
- * Same as ds_write_bts/pebs, but omit ownership checks.
- *
- * This is needed to have some other task than the owner of the
- * BTS/PEBS buffer or the parameter task itself write into the
- * respective buffer.
- */
-extern int ds_unchecked_write_bts(struct task_struct *task,
- const void *buffer, size_t size);
-extern int ds_unchecked_write_pebs(struct task_struct *task,
- const void *buffer, size_t size);
-
/*
* Reset the write pointer of the BTS/PEBS buffer.
*
* Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_~()
*/
-extern int ds_reset_bts(struct task_struct *task);
-extern int ds_reset_pebs(struct task_struct *task);
+extern int ds_reset_bts(struct bts_tracer *tracer);
+extern int ds_reset_pebs(struct pebs_tracer *tracer);
/*
* Clear the BTS/PEBS buffer and reset the write pointer.
*
* Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_~()
*/
-extern int ds_clear_bts(struct task_struct *task);
-extern int ds_clear_pebs(struct task_struct *task);
+extern int ds_clear_bts(struct bts_tracer *tracer);
+extern int ds_clear_pebs(struct pebs_tracer *tracer);
/*
* Provide the PEBS counter reset value.
*
* Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_pebs()
* value (out): the counter reset value
*/
-extern int ds_get_pebs_reset(struct task_struct *task, u64 *value);
+extern int ds_get_pebs_reset(struct pebs_tracer *tracer, u64 *value);
/*
* Set the PEBS counter reset value.
*
* Returns 0 on success; -Eerrno on error
*
- * task: the task to access;
- * NULL to access the current cpu
+ * tracer: the tracer handle returned from ds_request_pebs()
* value: the new counter reset value
*/
-extern int ds_set_pebs_reset(struct task_struct *task, u64 value);
+extern int ds_set_pebs_reset(struct pebs_tracer *tracer, u64 value);
/*
* Initialization
/*
* The DS context - part of struct thread_struct.
*/
+#define MAX_SIZEOF_DS (12 * 8)
+
struct ds_context {
/* pointer to the DS configuration; goes into MSR_IA32_DS_AREA */
- unsigned char *ds;
+ unsigned char ds[MAX_SIZEOF_DS];
/* the owner of the BTS and PEBS configuration, respectively */
- struct task_struct *owner[2];
- /* buffer overflow notification function for BTS and PEBS */
- ds_ovfl_callback_t callback[2];
- /* the original buffer address */
- void *buffer[2];
- /* the number of allocated pages for on-request allocated buffers */
- unsigned int pages[2];
+ struct ds_tracer *owner[2];
/* use count */
unsigned long count;
/* a pointer to the context location inside the thread_struct
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mm.h>
+#include <linux/kernel.h>
/*
};
static struct ds_configuration ds_cfg;
+/*
+ * A BTS or PEBS tracer.
+ *
+ * This holds the configuration of the tracer and serves as a handle
+ * to identify tracers.
+ */
+struct ds_tracer {
+ /* the DS context (partially) owned by this tracer */
+ struct ds_context *context;
+ /* the buffer provided on ds_request() and its size in bytes */
+ void *buffer;
+ size_t size;
+ /* the number of allocated pages for on-request allocated buffers */
+ unsigned int pages;
+};
+
+struct bts_tracer {
+ /* the common DS part */
+ struct ds_tracer ds;
+ /* buffer overflow notification function */
+ bts_ovfl_callback_t ovfl;
+};
+
+struct pebs_tracer {
+ /* the common DS part */
+ struct ds_tracer ds;
+ /* buffer overflow notification function */
+ pebs_ovfl_callback_t ovfl;
+};
/*
* Debug Store (DS) save area configuration (see Intel64 and IA32
(*(unsigned long *)base) = value;
}
+#define DS_ALIGNMENT (1 << 3) /* BTS and PEBS buffer alignment */
+
/*
* Locking is done only for allocating BTS or PEBS resources and for
* guarding context and buffer memory allocation.
- *
- * Most functions require the current task to own the ds context part
- * they are going to access. All the locking is done when validating
- * access to the context.
*/
static spinlock_t ds_lock = __SPIN_LOCK_UNLOCKED(ds_lock);
-/*
- * Validate that the current task is allowed to access the BTS/PEBS
- * buffer of the parameter task.
- *
- * Returns 0, if access is granted; -Eerrno, otherwise.
- */
-static inline int ds_validate_access(struct ds_context *context,
- enum ds_qualifier qual)
-{
- if (!context)
- return -EPERM;
-
- if (context->owner[qual] == current)
- return 0;
-
- return -EPERM;
-}
-
/*
* We either support (system-wide) per-cpu or per-thread allocation.
*
* Contexts are use-counted. They are allocated on first access and
* deallocated when the last user puts the context.
- *
- * We distinguish between an allocating and a non-allocating get of a
- * context:
- * - the allocating get is used for requesting BTS/PEBS resources. It
- * requires the caller to hold the global ds_lock.
- * - the non-allocating get is used for all other cases. A
- * non-existing context indicates an error. It acquires and releases
- * the ds_lock itself for obtaining the context.
- *
- * A context and its DS configuration are allocated and deallocated
- * together. A context always has a DS configuration of the
- * appropriate size.
*/
static DEFINE_PER_CPU(struct ds_context *, system_context);
#define this_system_context per_cpu(system_context, smp_processor_id())
-/*
- * Returns the pointer to the parameter task's context or to the
- * system-wide context, if task is NULL.
- *
- * Increases the use count of the returned context, if not NULL.
- */
static inline struct ds_context *ds_get_context(struct task_struct *task)
-{
- struct ds_context *context;
- unsigned long irq;
-
- spin_lock_irqsave(&ds_lock, irq);
-
- context = (task ? task->thread.ds_ctx : this_system_context);
- if (context)
- context->count++;
-
- spin_unlock_irqrestore(&ds_lock, irq);
-
- return context;
-}
-
-/*
- * Same as ds_get_context, but allocates the context and it's DS
- * structure, if necessary; returns NULL; if out of memory.
- */
-static inline struct ds_context *ds_alloc_context(struct task_struct *task)
{
struct ds_context **p_context =
(task ? &task->thread.ds_ctx : &this_system_context);
if (!context)
return NULL;
- context->ds = kzalloc(ds_cfg.sizeof_ds, GFP_KERNEL);
- if (!context->ds) {
- kfree(context);
- return NULL;
- }
-
spin_lock_irqsave(&ds_lock, irq);
if (*p_context) {
- kfree(context->ds);
kfree(context);
context = *p_context;
return context;
}
-/*
- * Decreases the use count of the parameter context, if not NULL.
- * Deallocates the context, if the use count reaches zero.
- */
static inline void ds_put_context(struct ds_context *context)
{
unsigned long irq;
if (!context->task || (context->task == current))
wrmsrl(MSR_IA32_DS_AREA, 0);
- put_tracer(context->task);
-
- /* free any leftover buffers from tracers that did not
- * deallocate them properly. */
- kfree(context->buffer[ds_bts]);
- kfree(context->buffer[ds_pebs]);
- kfree(context->ds);
kfree(context);
out:
spin_unlock_irqrestore(&ds_lock, irq);
/*
* Handle a buffer overflow
*
- * task: the task whose buffers are overflowing;
- * NULL for a buffer overflow on the current cpu
* context: the ds context
* qual: the buffer type
*/
-static void ds_overflow(struct task_struct *task, struct ds_context *context,
- enum ds_qualifier qual)
-{
- if (!context)
- return;
-
- if (context->callback[qual])
- (*context->callback[qual])(task);
-
- /* todo: do some more overflow handling */
+static void ds_overflow(struct ds_context *context, enum ds_qualifier qual)
+{
+ switch (qual) {
+ case ds_bts: {
+ struct bts_tracer *tracer =
+ container_of(context->owner[qual],
+ struct bts_tracer, ds);
+ if (tracer->ovfl)
+ tracer->ovfl(tracer);
+ }
+ break;
+ case ds_pebs: {
+ struct pebs_tracer *tracer =
+ container_of(context->owner[qual],
+ struct pebs_tracer, ds);
+ if (tracer->ovfl)
+ tracer->ovfl(tracer);
+ }
+ break;
+ }
}
static inline void *ds_allocate_buffer(size_t size, unsigned int *pages)
{
unsigned long rlim, vm, pgsz;
- void *buffer;
+ void *buffer = NULL;
pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ down_write(¤t->mm->mmap_sem);
+
rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
vm = current->mm->total_vm + pgsz;
if (rlim < vm)
- return NULL;
+ goto out;
rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
vm = current->mm->locked_vm + pgsz;
if (rlim < vm)
- return NULL;
+ goto out;
buffer = kzalloc(size, GFP_KERNEL);
if (!buffer)
- return NULL;
+ goto out;
current->mm->total_vm += pgsz;
current->mm->locked_vm += pgsz;
if (pages)
*pages = pgsz;
+ out:
+ up_write(¤t->mm->mmap_sem);
return buffer;
}
-static int ds_request(struct task_struct *task, void *base, size_t size,
- ds_ovfl_callback_t ovfl, enum ds_qualifier qual)
+static void ds_install_ds_config(struct ds_context *context,
+ enum ds_qualifier qual,
+ void *base, size_t size, size_t ith)
{
- struct ds_context *context;
unsigned long buffer, adj;
- const unsigned long alignment = (1 << 3);
+
+ /* adjust the buffer address and size to meet alignment
+ * constraints:
+ * - buffer is double-word aligned
+ * - size is multiple of record size
+ *
+ * We checked the size at the very beginning; we have enough
+ * space to do the adjustment.
+ */
+ buffer = (unsigned long)base;
+
+ adj = ALIGN(buffer, DS_ALIGNMENT) - buffer;
+ buffer += adj;
+ size -= adj;
+
+ size /= ds_cfg.sizeof_rec[qual];
+ size *= ds_cfg.sizeof_rec[qual];
+
+ ds_set(context->ds, qual, ds_buffer_base, buffer);
+ ds_set(context->ds, qual, ds_index, buffer);
+ ds_set(context->ds, qual, ds_absolute_maximum, buffer + size);
+
+ /* The value for 'no threshold' is -1, which will set the
+ * threshold outside of the buffer, just like we want it.
+ */
+ ds_set(context->ds, qual,
+ ds_interrupt_threshold, buffer + size - ith);
+}
+
+static int ds_request(struct ds_tracer *tracer, enum ds_qualifier qual,
+ struct task_struct *task,
+ void *base, size_t size, size_t th)
+{
+ struct ds_context *context;
unsigned long irq;
- int error = 0;
+ int error;
+ error = -EOPNOTSUPP;
if (!ds_cfg.sizeof_ds)
- return -EOPNOTSUPP;
+ goto out;
/* we require some space to do alignment adjustments below */
- if (size < (alignment + ds_cfg.sizeof_rec[qual]))
- return -EINVAL;
+ error = -EINVAL;
+ if (size < (DS_ALIGNMENT + ds_cfg.sizeof_rec[qual]))
+ goto out;
- /* buffer overflow notification is not yet implemented */
- if (ovfl)
- return -EOPNOTSUPP;
+ if (th != (size_t)-1) {
+ th *= ds_cfg.sizeof_rec[qual];
+
+ error = -EINVAL;
+ if (size <= th)
+ goto out;
+ }
+
+ error = -ENOMEM;
+ if (!base) {
+ base = ds_allocate_buffer(size, &tracer->pages);
+ if (!base)
+ goto out;
+ }
+ tracer->buffer = base;
+ tracer->size = size;
- context = ds_alloc_context(task);
+ error = -ENOMEM;
+ context = ds_get_context(task);
if (!context)
- return -ENOMEM;
+ goto out;
+ tracer->context = context;
+
spin_lock_irqsave(&ds_lock, irq);
error = -EPERM;
if (!check_tracer(task))
goto out_unlock;
-
get_tracer(task);
- error = -EALREADY;
- if (context->owner[qual] == current)
- goto out_put_tracer;
error = -EPERM;
- if (context->owner[qual] != NULL)
+ if (context->owner[qual])
goto out_put_tracer;
- context->owner[qual] = current;
+ context->owner[qual] = tracer;
spin_unlock_irqrestore(&ds_lock, irq);
- error = -ENOMEM;
- if (!base) {
- base = ds_allocate_buffer(size, &context->pages[qual]);
- if (!base)
- goto out_release;
-
- context->buffer[qual] = base;
- }
- error = 0;
+ ds_install_ds_config(context, qual, base, size, th);
- context->callback[qual] = ovfl;
-
- /* adjust the buffer address and size to meet alignment
- * constraints:
- * - buffer is double-word aligned
- * - size is multiple of record size
- *
- * We checked the size at the very beginning; we have enough
- * space to do the adjustment.
- */
- buffer = (unsigned long)base;
-
- adj = ALIGN(buffer, alignment) - buffer;
- buffer += adj;
- size -= adj;
-
- size /= ds_cfg.sizeof_rec[qual];
- size *= ds_cfg.sizeof_rec[qual];
-
- ds_set(context->ds, qual, ds_buffer_base, buffer);
- ds_set(context->ds, qual, ds_index, buffer);
- ds_set(context->ds, qual, ds_absolute_maximum, buffer + size);
-
- if (ovfl) {
- /* todo: select a suitable interrupt threshold */
- } else
- ds_set(context->ds, qual,
- ds_interrupt_threshold, buffer + size + 1);
-
- /* we keep the context until ds_release */
- return error;
-
- out_release:
- context->owner[qual] = NULL;
- ds_put_context(context);
- put_tracer(task);
- return error;
+ return 0;
out_put_tracer:
- spin_unlock_irqrestore(&ds_lock, irq);
- ds_put_context(context);
put_tracer(task);
- return error;
-
out_unlock:
spin_unlock_irqrestore(&ds_lock, irq);
ds_put_context(context);
+ tracer->context = NULL;
+ out:
return error;
}
-int ds_request_bts(struct task_struct *task, void *base, size_t size,
- ds_ovfl_callback_t ovfl)
+struct bts_tracer *ds_request_bts(struct task_struct *task,
+ void *base, size_t size,
+ bts_ovfl_callback_t ovfl, size_t th)
{
- return ds_request(task, base, size, ovfl, ds_bts);
-}
+ struct bts_tracer *tracer;
+ int error;
-int ds_request_pebs(struct task_struct *task, void *base, size_t size,
- ds_ovfl_callback_t ovfl)
-{
- return ds_request(task, base, size, ovfl, ds_pebs);
+ /* buffer overflow notification is not yet implemented */
+ error = -EOPNOTSUPP;
+ if (ovfl)
+ goto out;
+
+ error = -ENOMEM;
+ tracer = kzalloc(sizeof(*tracer), GFP_KERNEL);
+ if (!tracer)
+ goto out;
+ tracer->ovfl = ovfl;
+
+ error = ds_request(&tracer->ds, ds_bts, task, base, size, th);
+ if (error < 0)
+ goto out_tracer;
+
+ return tracer;
+
+ out_tracer:
+ (void)ds_release_bts(tracer);
+ out:
+ return ERR_PTR(error);
}
-static int ds_release(struct task_struct *task, enum ds_qualifier qual)
+struct pebs_tracer *ds_request_pebs(struct task_struct *task,
+ void *base, size_t size,
+ pebs_ovfl_callback_t ovfl, size_t th)
{
- struct ds_context *context;
+ struct pebs_tracer *tracer;
int error;
- context = ds_get_context(task);
- error = ds_validate_access(context, qual);
- if (error < 0)
+ /* buffer overflow notification is not yet implemented */
+ error = -EOPNOTSUPP;
+ if (ovfl)
goto out;
- kfree(context->buffer[qual]);
- context->buffer[qual] = NULL;
+ error = -ENOMEM;
+ tracer = kzalloc(sizeof(*tracer), GFP_KERNEL);
+ if (!tracer)
+ goto out;
+ tracer->ovfl = ovfl;
- current->mm->total_vm -= context->pages[qual];
- current->mm->locked_vm -= context->pages[qual];
- context->pages[qual] = 0;
- context->owner[qual] = NULL;
+ error = ds_request(&tracer->ds, ds_pebs, task, base, size, th);
+ if (error < 0)
+ goto out_tracer;
- /*
- * we put the context twice:
- * once for the ds_get_context
- * once for the corresponding ds_request
- */
- ds_put_context(context);
+ return tracer;
+
+ out_tracer:
+ (void)ds_release_pebs(tracer);
out:
- ds_put_context(context);
- return error;
+ return ERR_PTR(error);
+}
+
+static void ds_release(struct ds_tracer *tracer, enum ds_qualifier qual)
+{
+ if (tracer->context) {
+ BUG_ON(tracer->context->owner[qual] != tracer);
+ tracer->context->owner[qual] = NULL;
+
+ put_tracer(tracer->context->task);
+ ds_put_context(tracer->context);
+ }
+
+ if (tracer->pages) {
+ kfree(tracer->buffer);
+
+ down_write(¤t->mm->mmap_sem);
+
+ current->mm->total_vm -= tracer->pages;
+ current->mm->locked_vm -= tracer->pages;
+
+ up_write(¤t->mm->mmap_sem);
+ }
}
-int ds_release_bts(struct task_struct *task)
+int ds_release_bts(struct bts_tracer *tracer)
{
- return ds_release(task, ds_bts);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_release(&tracer->ds, ds_bts);
+ kfree(tracer);
+
+ return 0;
}
-int ds_release_pebs(struct task_struct *task)
+int ds_release_pebs(struct pebs_tracer *tracer)
{
- return ds_release(task, ds_pebs);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_release(&tracer->ds, ds_pebs);
+ kfree(tracer);
+
+ return 0;
}
-static int ds_get_index(struct task_struct *task, size_t *pos,
- enum ds_qualifier qual)
+static size_t ds_get_index(struct ds_context *context, enum ds_qualifier qual)
{
- struct ds_context *context;
unsigned long base, index;
- int error;
-
- context = ds_get_context(task);
- error = ds_validate_access(context, qual);
- if (error < 0)
- goto out;
base = ds_get(context->ds, qual, ds_buffer_base);
index = ds_get(context->ds, qual, ds_index);
- error = ((index - base) / ds_cfg.sizeof_rec[qual]);
- if (pos)
- *pos = error;
- out:
- ds_put_context(context);
- return error;
+ return (index - base) / ds_cfg.sizeof_rec[qual];
}
-int ds_get_bts_index(struct task_struct *task, size_t *pos)
+int ds_get_bts_index(struct bts_tracer *tracer, size_t *pos)
{
- return ds_get_index(task, pos, ds_bts);
+ if (!tracer)
+ return -EINVAL;
+
+ if (!pos)
+ return -EINVAL;
+
+ *pos = ds_get_index(tracer->ds.context, ds_bts);
+
+ return 0;
}
-int ds_get_pebs_index(struct task_struct *task, size_t *pos)
+int ds_get_pebs_index(struct pebs_tracer *tracer, size_t *pos)
{
- return ds_get_index(task, pos, ds_pebs);
+ if (!tracer)
+ return -EINVAL;
+
+ if (!pos)
+ return -EINVAL;
+
+ *pos = ds_get_index(tracer->ds.context, ds_pebs);
+
+ return 0;
}
-static int ds_get_end(struct task_struct *task, size_t *pos,
- enum ds_qualifier qual)
+static size_t ds_get_end(struct ds_context *context, enum ds_qualifier qual)
{
- struct ds_context *context;
- unsigned long base, end;
- int error;
-
- context = ds_get_context(task);
- error = ds_validate_access(context, qual);
- if (error < 0)
- goto out;
+ unsigned long base, max;
base = ds_get(context->ds, qual, ds_buffer_base);
- end = ds_get(context->ds, qual, ds_absolute_maximum);
+ max = ds_get(context->ds, qual, ds_absolute_maximum);
- error = ((end - base) / ds_cfg.sizeof_rec[qual]);
- if (pos)
- *pos = error;
- out:
- ds_put_context(context);
- return error;
+ return (max - base) / ds_cfg.sizeof_rec[qual];
}
-int ds_get_bts_end(struct task_struct *task, size_t *pos)
+int ds_get_bts_end(struct bts_tracer *tracer, size_t *pos)
{
- return ds_get_end(task, pos, ds_bts);
+ if (!tracer)
+ return -EINVAL;
+
+ if (!pos)
+ return -EINVAL;
+
+ *pos = ds_get_end(tracer->ds.context, ds_bts);
+
+ return 0;
}
-int ds_get_pebs_end(struct task_struct *task, size_t *pos)
+int ds_get_pebs_end(struct pebs_tracer *tracer, size_t *pos)
{
- return ds_get_end(task, pos, ds_pebs);
+ if (!tracer)
+ return -EINVAL;
+
+ if (!pos)
+ return -EINVAL;
+
+ *pos = ds_get_end(tracer->ds.context, ds_pebs);
+
+ return 0;
}
-static int ds_access(struct task_struct *task, size_t index,
- const void **record, enum ds_qualifier qual)
+static int ds_access(struct ds_context *context, enum ds_qualifier qual,
+ size_t index, const void **record)
{
- struct ds_context *context;
unsigned long base, idx;
- int error;
if (!record)
return -EINVAL;
- context = ds_get_context(task);
- error = ds_validate_access(context, qual);
- if (error < 0)
- goto out;
-
base = ds_get(context->ds, qual, ds_buffer_base);
idx = base + (index * ds_cfg.sizeof_rec[qual]);
- error = -EINVAL;
if (idx > ds_get(context->ds, qual, ds_absolute_maximum))
- goto out;
+ return -EINVAL;
*record = (const void *)idx;
- error = ds_cfg.sizeof_rec[qual];
- out:
- ds_put_context(context);
- return error;
+
+ return ds_cfg.sizeof_rec[qual];
}
-int ds_access_bts(struct task_struct *task, size_t index, const void **record)
+int ds_access_bts(struct bts_tracer *tracer, size_t index,
+ const void **record)
{
- return ds_access(task, index, record, ds_bts);
+ if (!tracer)
+ return -EINVAL;
+
+ return ds_access(tracer->ds.context, ds_bts, index, record);
}
-int ds_access_pebs(struct task_struct *task, size_t index, const void **record)
+int ds_access_pebs(struct pebs_tracer *tracer, size_t index,
+ const void **record)
{
- return ds_access(task, index, record, ds_pebs);
+ if (!tracer)
+ return -EINVAL;
+
+ return ds_access(tracer->ds.context, ds_pebs, index, record);
}
-static int ds_write(struct task_struct *task, const void *record, size_t size,
- enum ds_qualifier qual, int force)
+static int ds_write(struct ds_context *context, enum ds_qualifier qual,
+ const void *record, size_t size)
{
- struct ds_context *context;
- int error;
+ int bytes_written = 0;
if (!record)
return -EINVAL;
- error = -EPERM;
- context = ds_get_context(task);
- if (!context)
- goto out;
-
- if (!force) {
- error = ds_validate_access(context, qual);
- if (error < 0)
- goto out;
- }
-
- error = 0;
while (size) {
unsigned long base, index, end, write_end, int_th;
unsigned long write_size, adj_write_size;
write_end = end;
if (write_end <= index)
- goto out;
+ break;
write_size = min((unsigned long) size, write_end - index);
memcpy((void *)index, record, write_size);
record = (const char *)record + write_size;
- size -= write_size;
- error += write_size;
+ size -= write_size;
+ bytes_written += write_size;
adj_write_size = write_size / ds_cfg.sizeof_rec[qual];
adj_write_size *= ds_cfg.sizeof_rec[qual];
ds_set(context->ds, qual, ds_index, index);
if (index >= int_th)
- ds_overflow(task, context, qual);
+ ds_overflow(context, qual);
}
- out:
- ds_put_context(context);
- return error;
+ return bytes_written;
}
-int ds_write_bts(struct task_struct *task, const void *record, size_t size)
+int ds_write_bts(struct bts_tracer *tracer, const void *record, size_t size)
{
- return ds_write(task, record, size, ds_bts, /* force = */ 0);
-}
+ if (!tracer)
+ return -EINVAL;
-int ds_write_pebs(struct task_struct *task, const void *record, size_t size)
-{
- return ds_write(task, record, size, ds_pebs, /* force = */ 0);
+ return ds_write(tracer->ds.context, ds_bts, record, size);
}
-int ds_unchecked_write_bts(struct task_struct *task,
- const void *record, size_t size)
+int ds_write_pebs(struct pebs_tracer *tracer, const void *record, size_t size)
{
- return ds_write(task, record, size, ds_bts, /* force = */ 1);
-}
+ if (!tracer)
+ return -EINVAL;
-int ds_unchecked_write_pebs(struct task_struct *task,
- const void *record, size_t size)
-{
- return ds_write(task, record, size, ds_pebs, /* force = */ 1);
+ return ds_write(tracer->ds.context, ds_pebs, record, size);
}
-static int ds_reset_or_clear(struct task_struct *task,
- enum ds_qualifier qual, int clear)
+static void ds_reset_or_clear(struct ds_context *context,
+ enum ds_qualifier qual, int clear)
{
- struct ds_context *context;
unsigned long base, end;
- int error;
-
- context = ds_get_context(task);
- error = ds_validate_access(context, qual);
- if (error < 0)
- goto out;
base = ds_get(context->ds, qual, ds_buffer_base);
end = ds_get(context->ds, qual, ds_absolute_maximum);
memset((void *)base, 0, end - base);
ds_set(context->ds, qual, ds_index, base);
-
- error = 0;
- out:
- ds_put_context(context);
- return error;
}
-int ds_reset_bts(struct task_struct *task)
+int ds_reset_bts(struct bts_tracer *tracer)
{
- return ds_reset_or_clear(task, ds_bts, /* clear = */ 0);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_reset_or_clear(tracer->ds.context, ds_bts, /* clear = */ 0);
+
+ return 0;
}
-int ds_reset_pebs(struct task_struct *task)
+int ds_reset_pebs(struct pebs_tracer *tracer)
{
- return ds_reset_or_clear(task, ds_pebs, /* clear = */ 0);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_reset_or_clear(tracer->ds.context, ds_pebs, /* clear = */ 0);
+
+ return 0;
}
-int ds_clear_bts(struct task_struct *task)
+int ds_clear_bts(struct bts_tracer *tracer)
{
- return ds_reset_or_clear(task, ds_bts, /* clear = */ 1);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_reset_or_clear(tracer->ds.context, ds_bts, /* clear = */ 1);
+
+ return 0;
}
-int ds_clear_pebs(struct task_struct *task)
+int ds_clear_pebs(struct pebs_tracer *tracer)
{
- return ds_reset_or_clear(task, ds_pebs, /* clear = */ 1);
+ if (!tracer)
+ return -EINVAL;
+
+ ds_reset_or_clear(tracer->ds.context, ds_pebs, /* clear = */ 1);
+
+ return 0;
}
-int ds_get_pebs_reset(struct task_struct *task, u64 *value)
+int ds_get_pebs_reset(struct pebs_tracer *tracer, u64 *value)
{
- struct ds_context *context;
- int error;
+ if (!tracer)
+ return -EINVAL;
if (!value)
return -EINVAL;
- context = ds_get_context(task);
- error = ds_validate_access(context, ds_pebs);
- if (error < 0)
- goto out;
-
- *value = *(u64 *)(context->ds + (ds_cfg.sizeof_field * 8));
+ *value = *(u64 *)(tracer->ds.context->ds + (ds_cfg.sizeof_field * 8));
- error = 0;
- out:
- ds_put_context(context);
- return error;
+ return 0;
}
-int ds_set_pebs_reset(struct task_struct *task, u64 value)
+int ds_set_pebs_reset(struct pebs_tracer *tracer, u64 value)
{
- struct ds_context *context;
- int error;
-
- context = ds_get_context(task);
- error = ds_validate_access(context, ds_pebs);
- if (error < 0)
- goto out;
+ if (!tracer)
+ return -EINVAL;
- *(u64 *)(context->ds + (ds_cfg.sizeof_field * 8)) = value;
+ *(u64 *)(tracer->ds.context->ds + (ds_cfg.sizeof_field * 8)) = value;
- error = 0;
- out:
- ds_put_context(context);
- return error;
+ return 0;
}
static const struct ds_configuration ds_cfg_var = {
ds_configure(const struct ds_configuration *cfg)
{
ds_cfg = *cfg;
+
+ printk(KERN_INFO "DS available\n");
+
+ BUG_ON(MAX_SIZEOF_DS < ds_cfg.sizeof_ds);
}
void __cpuinit ds_init_intel(struct cpuinfo_x86 *c)
* is dying. There should not be any user of that context left
* to disturb us, anymore. */
unsigned long leftovers = context->count;
- while (leftovers--)
+ while (leftovers--) {
+ put_tracer(context->task);
ds_put_context(context);
+ }
}
projects / mirror_ubuntu-kernels.git / commitdiff