gdb/target-dcache.c

   1 /* Copyright (C) 1992-2021 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 #include "cli/cli-cmds.h"
  23
  24 /* The target dcache is kept per-address-space.  This key lets us
  25    associate the cache with the address space.  */
  26
  27 static const struct address_space_key<DCACHE, dcache_deleter>
  28   target_dcache_aspace_key;
  29
  30 /* Target dcache is initialized or not.  */
  31
  32 int
  33 target_dcache_init_p (void)
  34 {
  35   DCACHE *dcache
  36     = target_dcache_aspace_key.get (current_program_space->aspace);
  37
  38   return (dcache != NULL);
  39 }
  40
  41 /* Invalidate the target dcache.  */
  42
  43 void
  44 target_dcache_invalidate (void)
  45 {
  46   DCACHE *dcache
  47     = target_dcache_aspace_key.get (current_program_space->aspace);
  48
  49   if (dcache != NULL)
  50     dcache_invalidate (dcache);
  51 }
  52
  53 /* Return the target dcache.  Return NULL if target dcache is not
  54    initialized yet.  */
  55
  56 DCACHE *
  57 target_dcache_get (void)
  58 {
  59   return target_dcache_aspace_key.get (current_program_space->aspace);
  60 }
  61
  62 /* Return the target dcache.  If it is not initialized yet, initialize
  63    it.  */
  64
  65 DCACHE *
  66 target_dcache_get_or_init (void)
  67 {
  68   DCACHE *dcache
  69     = target_dcache_aspace_key.get (current_program_space->aspace);
  70
  71   if (dcache == NULL)
  72     {
  73       dcache = dcache_init ();
  74       target_dcache_aspace_key.set (current_program_space->aspace, dcache);
  75     }
  76
  77   return dcache;
  78 }
  79
  80 /* The option sets this.  */
  81 static bool stack_cache_enabled_1 = true;
  82 /* And set_stack_cache updates this.
  83    The reason for the separation is so that we don't flush the cache for
  84    on->on transitions.  */
  85 static int stack_cache_enabled = 1;
  86
  87 /* This is called *after* the stack-cache has been set.
  88    Flush the cache for off->on and on->off transitions.
  89    There's no real need to flush the cache for on->off transitions,
  90    except cleanliness.  */
  91
  92 static void
  93 set_stack_cache (const char *args, int from_tty, struct cmd_list_element *c)
  94 {
  95   if (stack_cache_enabled != stack_cache_enabled_1)
  96     target_dcache_invalidate ();
  97
  98   stack_cache_enabled = stack_cache_enabled_1;
  99 }
 100
 101 static void
 102 show_stack_cache (struct ui_file *file, int from_tty,
 103                   struct cmd_list_element *c, const char *value)
 104 {
 105   fprintf_filtered (file, _("Cache use for stack accesses is %s.\n"), value);
 106 }
 107
 108 /* Return true if "stack cache" is enabled, otherwise, return false.  */
 109
 110 int
 111 stack_cache_enabled_p (void)
 112 {
 113   return stack_cache_enabled;
 114 }
 115
 116 /* The option sets this.  */
 117
 118 static bool code_cache_enabled_1 = true;
 119
 120 /* And set_code_cache updates this.
 121    The reason for the separation is so that we don't flush the cache for
 122    on->on transitions.  */
 123 static int code_cache_enabled = 1;
 124
 125 /* This is called *after* the code-cache has been set.
 126    Flush the cache for off->on and on->off transitions.
 127    There's no real need to flush the cache for on->off transitions,
 128    except cleanliness.  */
 129
 130 static void
 131 set_code_cache (const char *args, int from_tty, struct cmd_list_element *c)
 132 {
 133   if (code_cache_enabled != code_cache_enabled_1)
 134     target_dcache_invalidate ();
 135
 136   code_cache_enabled = code_cache_enabled_1;
 137 }
 138
 139 /* Show option "code-cache".  */
 140
 141 static void
 142 show_code_cache (struct ui_file *file, int from_tty,
 143                  struct cmd_list_element *c, const char *value)
 144 {
 145   fprintf_filtered (file, _("Cache use for code accesses is %s.\n"), value);
 146 }
 147
 148 /* Return true if "code cache" is enabled, otherwise, return false.  */
 149
 150 int
 151 code_cache_enabled_p (void)
 152 {
 153   return code_cache_enabled;
 154 }
 155
 156 /* Implement the 'maint flush dcache' command.  */
 157
 158 static void
 159 maint_flush_dcache_command (const char *command, int from_tty)
 160 {
 161   target_dcache_invalidate ();
 162   if (from_tty)
 163     printf_filtered (_("The dcache was flushed.\n"));
 164 }
 165
 166 void _initialize_target_dcache ();
 167 void
 168 _initialize_target_dcache ()
 169 {
 170   add_setshow_boolean_cmd ("stack-cache", class_support,
 171                            &stack_cache_enabled_1, _("\
 172 Set cache use for stack access."), _("\
 173 Show cache use for stack access."), _("\
 174 When on, use the target memory cache for all stack access, regardless of any\n\
 175 configured memory regions.  This improves remote performance significantly.\n\
 176 By default, caching for stack access is on."),
 177                            set_stack_cache,
 178                            show_stack_cache,
 179                            &setlist, &showlist);
 180
 181   add_setshow_boolean_cmd ("code-cache", class_support,
 182                            &code_cache_enabled_1, _("\
 183 Set cache use for code segment access."), _("\
 184 Show cache use for code segment access."), _("\
 185 When on, use the target memory cache for all code segment accesses,\n\
 186 regardless of any configured memory regions.  This improves remote\n\
 187 performance significantly.  By default, caching for code segment\n\
 188 access is on."),
 189                            set_code_cache,
 190                            show_code_cache,
 191                            &setlist, &showlist);
 192
 193   add_cmd ("dcache", class_maintenance, maint_flush_dcache_command,
 194            _("\
 195 Force gdb to flush its target memory data cache.\n\
 196 \n\
 197 The dcache caches all target memory accesses where possible, this\n\
 198 includes the stack-cache and the code-cache."),
 199            &maintenanceflushlist);
 200 }