gdb/target-dcache.c

   1 /* Copyright (C) 1992-2013 Free Software Foundation, Inc.
   2
   3    This file is part of GDB.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include "defs.h"
  19 #include "target-dcache.h"
  20 #include "gdbcmd.h"
  21 #include "progspace.h"
  22
  23 /* The target dcache is kept per-address-space.  This key lets us
  24    associate the cache with the address space.  */
  25
  26 static const struct address_space_data *target_dcache_aspace_key;
  27
  28 /* Clean up dcache, represented by ARG, which is associated with
  29    ASPACE.  */
  30
  31 static void
  32 target_dcache_cleanup (struct address_space *aspace, void *arg)
  33 {
  34   dcache_free (arg);
  35 }
  36
  37 /* Target dcache is initialized or not.  */
  38
  39 int
  40 target_dcache_init_p (void)
  41 {
  42   DCACHE *dcache = address_space_data (current_program_space->aspace,
  43                                        target_dcache_aspace_key);
  44
  45   return (dcache != NULL);
  46 }
  47
  48 /* Invalidate the target dcache.  */
  49
  50 void
  51 target_dcache_invalidate (void)
  52 {
  53   DCACHE *dcache = address_space_data (current_program_space->aspace,
  54                                        target_dcache_aspace_key);
  55
  56   if (dcache != NULL)
  57     dcache_invalidate (dcache);
  58 }
  59
  60 /* Return the target dcache.  Return NULL if target dcache is not
  61    initialized yet.  */
  62
  63 DCACHE *
  64 target_dcache_get (void)
  65 {
  66   DCACHE *dcache = address_space_data (current_program_space->aspace,
  67                                        target_dcache_aspace_key);
  68
  69   return dcache;
  70 }
  71
  72 /* Return the target dcache.  If it is not initialized yet, initialize
  73    it.  */
  74
  75 DCACHE *
  76 target_dcache_get_or_init (void)
  77 {
  78   DCACHE *dcache = address_space_data (current_program_space->aspace,
  79                                        target_dcache_aspace_key);
  80
  81   if (dcache == NULL)
  82     {
  83       dcache = dcache_init ();
  84       set_address_space_data (current_program_space->aspace,
  85                               target_dcache_aspace_key, dcache);
  86     }
  87
  88   return dcache;
  89 }
  90
  91 /* The option sets this.  */
  92 static int stack_cache_enabled_p_1 = 1;
  93 /* And set_stack_cache_enabled_p updates this.
  94    The reason for the separation is so that we don't flush the cache for
  95    on->on transitions.  */
  96 static int stack_cache_enabled_p = 1;
  97
  98 /* This is called *after* the stack-cache has been set.
  99    Flush the cache for off->on and on->off transitions.
 100    There's no real need to flush the cache for on->off transitions,
 101    except cleanliness.  */
 102
 103 static void
 104 set_stack_cache_enabled_p (char *args, int from_tty,
 105                            struct cmd_list_element *c)
 106 {
 107   if (stack_cache_enabled_p != stack_cache_enabled_p_1)
 108     target_dcache_invalidate ();
 109
 110   stack_cache_enabled_p = stack_cache_enabled_p_1;
 111 }
 112
 113 static void
 114 show_stack_cache_enabled_p (struct ui_file *file, int from_tty,
 115                             struct cmd_list_element *c, const char *value)
 116 {
 117   fprintf_filtered (file, _("Cache use for stack accesses is %s.\n"), value);
 118 }
 119
 120 /* Return true if "stack cache" is enabled, otherwise, return false.  */
 121
 122 int
 123 stack_cache_enabled (void)
 124 {
 125   return stack_cache_enabled_p;
 126 }
 127
 128 /* -Wmissing-prototypes */
 129 extern initialize_file_ftype _initialize_target_dcache;
 130
 131 void
 132 _initialize_target_dcache (void)
 133 {
 134   add_setshow_boolean_cmd ("stack-cache", class_support,
 135                            &stack_cache_enabled_p_1, _("\
 136 Set cache use for stack access."), _("\
 137 Show cache use for stack access."), _("\
 138 When on, use the data cache for all stack access, regardless of any\n\
 139 configured memory regions.  This improves remote performance significantly.\n\
 140 By default, caching for stack access is on."),
 141                            set_stack_cache_enabled_p,
 142                            show_stack_cache_enabled_p,
 143                            &setlist, &showlist);
 144
 145   target_dcache_aspace_key
 146     = register_address_space_data_with_cleanup (NULL,
 147                                                 target_dcache_cleanup);
 148 }