x86, bts: cleanups

Impact: cleanup, no code changed

Cc: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090313104218.A30096@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 80 insertions, 62 deletions

diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c
index d9cab716805..7363e01ba08 100644
--- a/arch/x86/kernel/ds.c
+++ b/arch/x86/kernel/ds.c
@@ -19,43 +19,52 @@
  * Markus Metzger <markus.t.metzger@intel.com>, 2007-2009
  */
 
-
-#include <asm/ds.h>
-
-#include <linux/errno.h>
+#include <linux/kernel.h>
 #include <linux/string.h>
-#include <linux/slab.h>
+#include <linux/errno.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 #include <linux/mm.h>
-#include <linux/kernel.h>
+
+#include <asm/ds.h>
 
 #include "ds_selftest.h"
 
 /*
- * The configuration for a particular DS hardware implementation.
+ * The configuration for a particular DS hardware implementation:
  */
 struct ds_configuration {
-        /* The name of the configuration. */
-        const char *name;
-        /* The size of pointer-typed fields in DS, BTS, and PEBS. */
-        unsigned char  sizeof_ptr_field;
-        /* The size of a BTS/PEBS record in bytes. */
-        unsigned char  sizeof_rec[2];
-        /* Control bit-masks indexed by enum ds_feature. */
-        unsigned long ctl[dsf_ctl_max];
+        /* The name of the configuration: */
+        const char              *name;
+
+        /* The size of pointer-typed fields in DS, BTS, and PEBS: */
+        unsigned char           sizeof_ptr_field;
+
+        /* The size of a BTS/PEBS record in bytes: */
+        unsigned char           sizeof_rec[2];
+
+        /* Control bit-masks indexed by enum ds_feature: */
+        unsigned long           ctl[dsf_ctl_max];
 };
 static DEFINE_PER_CPU(struct ds_configuration, ds_cfg_array);
 
 #define ds_cfg per_cpu(ds_cfg_array, smp_processor_id())
 
-#define MAX_SIZEOF_DS (12 * 8)  /* Maximal size of a DS configuration. */
-#define MAX_SIZEOF_BTS (3 * 8)  /* Maximal size of a BTS record. */
-#define DS_ALIGNMENT (1 << 3)   /* BTS and PEBS buffer alignment. */
+/* Maximal size of a DS configuration: */
+#define MAX_SIZEOF_DS           (12 * 8)
 
-#define BTS_CONTROL \
- (ds_cfg.ctl[dsf_bts] | ds_cfg.ctl[dsf_bts_kernel] | ds_cfg.ctl[dsf_bts_user] |\
-  ds_cfg.ctl[dsf_bts_overflow])
+/* Maximal size of a BTS record: */
+#define MAX_SIZEOF_BTS          (3 * 8)
 
+/* BTS and PEBS buffer alignment: */
+#define DS_ALIGNMENT            (1 << 3)
+
+/* Mask of control bits in the DS MSR register: */
+#define BTS_CONTROL                               \
+        ( ds_cfg.ctl[dsf_bts]                   | \
+          ds_cfg.ctl[dsf_bts_kernel]            | \
+          ds_cfg.ctl[dsf_bts_user]              | \
+          ds_cfg.ctl[dsf_bts_overflow] )
 
 /*
  * A BTS or PEBS tracer.
@@ -65,28 +74,32 @@ static DEFINE_PER_CPU(struct ds_configuration, ds_cfg_array);
  */
 struct ds_tracer {
         /* The DS context (partially) owned by this tracer. */
-        struct ds_context *context;
+        struct ds_context       *context;
         /* The buffer provided on ds_request() and its size in bytes. */
-        void *buffer;
-        size_t size;
+        void                    *buffer;
+        size_t                  size;
 };
 
 struct bts_tracer {
-        /* The common DS part. */
-        struct ds_tracer ds;
-        /* The trace including the DS configuration. */
-        struct bts_trace trace;
-        /* Buffer overflow notification function. */
-        bts_ovfl_callback_t ovfl;
+        /* The common DS part: */
+        struct ds_tracer        ds;
+
+        /* The trace including the DS configuration: */
+        struct bts_trace        trace;
+
+        /* Buffer overflow notification function: */
+        bts_ovfl_callback_t     ovfl;
 };
 
 struct pebs_tracer {
-        /* The common DS part. */
-        struct ds_tracer ds;
-        /* The trace including the DS configuration. */
-        struct pebs_trace trace;
-        /* Buffer overflow notification function. */
-        pebs_ovfl_callback_t ovfl;
+        /* The common DS part: */
+        struct ds_tracer        ds;
+
+        /* The trace including the DS configuration: */
+        struct pebs_trace       trace;
+
+        /* Buffer overflow notification function: */
+        pebs_ovfl_callback_t    ovfl;
 };
 
 /*
@@ -95,6 +108,7 @@ struct pebs_tracer {
  *
  * The DS configuration consists of the following fields; different
  * architetures vary in the size of those fields.
+ *
  * - double-word aligned base linear address of the BTS buffer
  * - write pointer into the BTS buffer
  * - end linear address of the BTS buffer (one byte beyond the end of
@@ -133,19 +147,20 @@ enum ds_field {
 };
 
 enum ds_qualifier {
-        ds_bts  = 0,
+        ds_bts = 0,
         ds_pebs
 };
 
-static inline unsigned long ds_get(const unsigned char *base,
-                                   enum ds_qualifier qual, enum ds_field field)
+static inline unsigned long
+ds_get(const unsigned char *base, enum ds_qualifier qual, enum ds_field field)
 {
         base += (ds_cfg.sizeof_ptr_field * (field + (4 * qual)));
         return *(unsigned long *)base;
 }
 
-static inline void ds_set(unsigned char *base, enum ds_qualifier qual,
-                          enum ds_field field, unsigned long value)
+static inline void
+ds_set(unsigned char *base, enum ds_qualifier qual, enum ds_field field,
+       unsigned long value)
 {
         base += (ds_cfg.sizeof_ptr_field * (field + (4 * qual)));
         (*(unsigned long *)base) = value;
@@ -157,7 +172,6 @@ static inline void ds_set(unsigned char *base, enum ds_qualifier qual,
  */
 static DEFINE_SPINLOCK(ds_lock);
 
-
 /*
  * We either support (system-wide) per-cpu or per-thread allocation.
  * We distinguish the two based on the task_struct pointer, where a
@@ -211,17 +225,21 @@ static inline int check_tracer(struct task_struct *task)
  * deallocated when the last user puts the context.
  */
 struct ds_context {
-        /* The DS configuration; goes into MSR_IA32_DS_AREA. */
-        unsigned char ds[MAX_SIZEOF_DS];
-        /* The owner of the BTS and PEBS configuration, respectively. */
-        struct bts_tracer *bts_master;
-        struct pebs_tracer *pebs_master;
-        /* Use count. */
+        /* The DS configuration; goes into MSR_IA32_DS_AREA: */
+        unsigned char           ds[MAX_SIZEOF_DS];
+
+        /* The owner of the BTS and PEBS configuration, respectively: */
+        struct bts_tracer       *bts_master;
+        struct pebs_tracer      *pebs_master;
+
+        /* Use count: */
         unsigned long count;
-        /* Pointer to the context pointer field. */
-        struct ds_context **this;
-        /* The traced task; NULL for current cpu. */
-        struct task_struct *task;
+
+        /* Pointer to the context pointer field: */
+        struct ds_context       **this;
+
+        /* The traced task; NULL for current cpu: */
+        struct task_struct      *task;
 };
 
 static DEFINE_PER_CPU(struct ds_context *, system_context_array);
@@ -328,9 +346,9 @@ static void ds_overflow(struct ds_context *context, enum ds_qualifier qual)
  * The remainder of any partially written record is zeroed out.
  *
  * context: the DS context
- * qual: the buffer type
- * record: the data to write
- * size: the size of the data
+ * qual:    the buffer type
+ * record:  the data to write
+ * size:    the size of the data
  */
 static int ds_write(struct ds_context *context, enum ds_qualifier qual,
                     const void *record, size_t size)
@@ -429,12 +447,12 @@ enum bts_field {
         bts_to,
         bts_flags,
 
-        bts_qual = bts_from,
-        bts_jiffies = bts_to,
-        bts_pid = bts_flags,
+        bts_qual                = bts_from,
+        bts_jiffies             = bts_to,
+        bts_pid                 = bts_flags,
 
-        bts_qual_mask = (bts_qual_max - 1),
-        bts_escape = ((unsigned long)-1 & ~bts_qual_mask)
+        bts_qual_mask           = (bts_qual_max - 1),
+        bts_escape              = ((unsigned long)-1 & ~bts_qual_mask)
 };
 
 static inline unsigned long bts_get(const char *base, enum bts_field field)
@@ -461,8 +479,8 @@ static inline void bts_set(char *base, enum bts_field field, unsigned long val)
  *
  * return: bytes read/written on success; -Eerrno, otherwise
  */
-static int bts_read(struct bts_tracer *tracer, const void *at,
-                    struct bts_struct *out)
+static int
+bts_read(struct bts_tracer *tracer, const void *at, struct bts_struct *out)
 {
         if (!tracer)
                 return -EINVAL;