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_1 = 1;
  93 /* And set_stack_cache 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 = 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 (char *args, int from_tty, struct cmd_list_element *c)
 105 {
 106   if (stack_cache_enabled != stack_cache_enabled_1)
 107     target_dcache_invalidate ();
 108
 109   stack_cache_enabled = stack_cache_enabled_1;
 110 }
 111
 112 static void
 113 show_stack_cache (struct ui_file *file, int from_tty,
 114                   struct cmd_list_element *c, const char *value)
 115 {
 116   fprintf_filtered (file, _("Cache use for stack accesses is %s.\n"), value);
 117 }
 118
 119 /* Return true if "stack cache" is enabled, otherwise, return false.  */
 120
 121 int
 122 stack_cache_enabled_p (void)
 123 {
 124   return stack_cache_enabled;
 125 }
 126
 127 /* -Wmissing-prototypes */
 128 extern initialize_file_ftype _initialize_target_dcache;
 129
 130 void
 131 _initialize_target_dcache (void)
 132 {
 133   add_setshow_boolean_cmd ("stack-cache", class_support,
 134                            &stack_cache_enabled_1, _("\
 135 Set cache use for stack access."), _("\
 136 Show cache use for stack access."), _("\
 137 When on, use the target memory cache for all stack access, regardless of any\n\
 138 configured memory regions.  This improves remote performance significantly.\n\
 139 By default, caching for stack access is on."),
 140                            set_stack_cache,
 141                            show_stack_cache,
 142                            &setlist, &showlist);
 143
 144   target_dcache_aspace_key
 145     = register_address_space_data_with_cleanup (NULL,
 146                                                 target_dcache_cleanup);
 147 }