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OS-5192 need faster clock_gettime
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Joshua M. Clulow <jmc@joyent.com>
Reviewed by: Ryan Zezeski <ryan@zinascii.com>
    
      
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          --- old/usr/src/uts/i86pc/os/mlsetup.c
          +++ new/usr/src/uts/i86pc/os/mlsetup.c
   1    1  /*
   2    2   * CDDL HEADER START
   3    3   *
   4    4   * The contents of this file are subject to the terms of the
   5    5   * Common Development and Distribution License (the "License").
   6    6   * You may not use this file except in compliance with the License.
   7    7   *
   8    8   * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9    9   * or http://www.opensolaris.org/os/licensing.
  10   10   * See the License for the specific language governing permissions
  11   11   * and limitations under the License.
  12   12   *
  13   13   * When distributing Covered Code, include this CDDL HEADER in each
  14   14   * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15   15   * If applicable, add the following below this CDDL HEADER, with the
  
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  16   16   * fields enclosed by brackets "[]" replaced with your own identifying
  17   17   * information: Portions Copyright [yyyy] [name of copyright owner]
  18   18   *
  19   19   * CDDL HEADER END
  20   20   */
  21   21  /*
  22   22   * Copyright (c) 2012 Gary Mills
  23   23   *
  24   24   * Copyright (c) 1993, 2010, Oracle and/or its affiliates. All rights reserved.
  25   25   * Copyright (c) 2011 by Delphix. All rights reserved.
       26 + * Copyright 2016 Joyent, Inc.
  26   27   */
  27   28  /*
  28   29   * Copyright (c) 2010, Intel Corporation.
  29   30   * All rights reserved.
  30   31   */
  31   32  
  32   33  #include <sys/types.h>
  33   34  #include <sys/sysmacros.h>
  34   35  #include <sys/disp.h>
  35   36  #include <sys/promif.h>
  36   37  #include <sys/clock.h>
  37   38  #include <sys/cpuvar.h>
  38   39  #include <sys/stack.h>
  39   40  #include <vm/as.h>
  40   41  #include <vm/hat.h>
  41   42  #include <sys/reboot.h>
  42   43  #include <sys/avintr.h>
  43   44  #include <sys/vtrace.h>
  44   45  #include <sys/proc.h>
  45   46  #include <sys/thread.h>
  46   47  #include <sys/cpupart.h>
  47   48  #include <sys/pset.h>
  48   49  #include <sys/copyops.h>
  49   50  #include <sys/pg.h>
  50   51  #include <sys/disp.h>
  51   52  #include <sys/debug.h>
  52   53  #include <sys/sunddi.h>
  53   54  #include <sys/x86_archext.h>
  
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  54   55  #include <sys/privregs.h>
  55   56  #include <sys/machsystm.h>
  56   57  #include <sys/ontrap.h>
  57   58  #include <sys/bootconf.h>
  58   59  #include <sys/boot_console.h>
  59   60  #include <sys/kdi_machimpl.h>
  60   61  #include <sys/archsystm.h>
  61   62  #include <sys/promif.h>
  62   63  #include <sys/pci_cfgspace.h>
  63   64  #include <sys/bootvfs.h>
       65 +#include <sys/tsc.h>
  64   66  #ifdef __xpv
  65   67  #include <sys/hypervisor.h>
  66   68  #else
  67   69  #include <sys/xpv_support.h>
  68   70  #endif
  69   71  
  70   72  /*
  71   73   * some globals for patching the result of cpuid
  72   74   * to solve problems w/ creative cpu vendors
  73   75   */
  74   76  
  75   77  extern uint32_t cpuid_feature_ecx_include;
  76   78  extern uint32_t cpuid_feature_ecx_exclude;
  77   79  extern uint32_t cpuid_feature_edx_include;
  78   80  extern uint32_t cpuid_feature_edx_exclude;
  79   81  
  80   82  /*
  81   83   * Set console mode
  82   84   */
  83   85  static void
  84   86  set_console_mode(uint8_t val)
  85   87  {
  86   88          struct bop_regs rp = {0};
  87   89  
  88   90          rp.eax.byte.ah = 0x0;
  89   91          rp.eax.byte.al = val;
  90   92          rp.ebx.word.bx = 0x0;
  91   93  
  92   94          BOP_DOINT(bootops, 0x10, &rp);
  93   95  }
  94   96  
  95   97  
  96   98  /*
  97   99   * Setup routine called right before main(). Interposing this function
  98  100   * before main() allows us to call it in a machine-independent fashion.
  99  101   */
 100  102  void
 101  103  mlsetup(struct regs *rp)
 102  104  {
 103  105          u_longlong_t prop_value;
 104  106          extern struct classfuncs sys_classfuncs;
 105  107          extern disp_t cpu0_disp;
 106  108          extern char t0stack[];
 107  109          extern int post_fastreboot;
 108  110          extern uint64_t plat_dr_options;
 109  111  
 110  112          ASSERT_STACK_ALIGNED();
 111  113  
 112  114          /*
 113  115           * initialize cpu_self
 114  116           */
 115  117          cpu[0]->cpu_self = cpu[0];
 116  118  
 117  119  #if defined(__xpv)
 118  120          /*
 119  121           * Point at the hypervisor's virtual cpu structure
 120  122           */
 121  123          cpu[0]->cpu_m.mcpu_vcpu_info = &HYPERVISOR_shared_info->vcpu_info[0];
 122  124  #endif
 123  125  
 124  126          /*
 125  127           * check if we've got special bits to clear or set
 126  128           * when checking cpu features
 127  129           */
 128  130  
 129  131          if (bootprop_getval("cpuid_feature_ecx_include", &prop_value) != 0)
 130  132                  cpuid_feature_ecx_include = 0;
 131  133          else
 132  134                  cpuid_feature_ecx_include = (uint32_t)prop_value;
 133  135  
 134  136          if (bootprop_getval("cpuid_feature_ecx_exclude", &prop_value) != 0)
 135  137                  cpuid_feature_ecx_exclude = 0;
 136  138          else
 137  139                  cpuid_feature_ecx_exclude = (uint32_t)prop_value;
 138  140  
 139  141          if (bootprop_getval("cpuid_feature_edx_include", &prop_value) != 0)
 140  142                  cpuid_feature_edx_include = 0;
 141  143          else
 142  144                  cpuid_feature_edx_include = (uint32_t)prop_value;
 143  145  
 144  146          if (bootprop_getval("cpuid_feature_edx_exclude", &prop_value) != 0)
 145  147                  cpuid_feature_edx_exclude = 0;
 146  148          else
 147  149                  cpuid_feature_edx_exclude = (uint32_t)prop_value;
 148  150  
 149  151          /*
 150  152           * Initialize idt0, gdt0, ldt0_default, ktss0 and dftss.
 151  153           */
 152  154          init_desctbls();
 153  155  
 154  156          /*
 155  157           * lgrp_init() and possibly cpuid_pass1() need PCI config
 156  158           * space access
 157  159           */
 158  160  #if defined(__xpv)
 159  161          if (DOMAIN_IS_INITDOMAIN(xen_info))
 160  162                  pci_cfgspace_init();
 161  163  #else
 162  164          pci_cfgspace_init();
 163  165          /*
 164  166           * Initialize the platform type from CPU 0 to ensure that
 165  167           * determine_platform() is only ever called once.
 166  168           */
 167  169          determine_platform();
 168  170  #endif
 169  171  
 170  172          /*
 171  173           * The first lightweight pass (pass0) through the cpuid data
 172  174           * was done in locore before mlsetup was called.  Do the next
 173  175           * pass in C code.
 174  176           *
 175  177           * The x86_featureset is initialized here based on the capabilities
 176  178           * of the boot CPU.  Note that if we choose to support CPUs that have
 177  179           * different feature sets (at which point we would almost certainly
 178  180           * want to set the feature bits to correspond to the feature
 179  181           * minimum) this value may be altered.
 180  182           */
 181  183          cpuid_pass1(cpu[0], x86_featureset);
 182  184  
 183  185  #if !defined(__xpv)
 184  186          if ((get_hwenv() & HW_XEN_HVM) != 0)
 185  187                  xen_hvm_init();
 186  188  
 187  189          /*
 188  190           * Before we do anything with the TSCs, we need to work around
 189  191           * Intel erratum BT81.  On some CPUs, warm reset does not
 190  192           * clear the TSC.  If we are on such a CPU, we will clear TSC ourselves
 191  193           * here.  Other CPUs will clear it when we boot them later, and the
 192  194           * resulting skew will be handled by tsc_sync_master()/_slave();
 193  195           * note that such skew already exists and has to be handled anyway.
 194  196           *
 195  197           * We do this only on metal.  This same problem can occur with a
 196  198           * hypervisor that does not happen to virtualise a TSC that starts from
 197  199           * zero, regardless of CPU type; however, we do not expect hypervisors
 198  200           * that do not virtualise TSC that way to handle writes to TSC
 199  201           * correctly, either.
 200  202           */
 201  203          if (get_hwenv() == HW_NATIVE &&
 202  204              cpuid_getvendor(CPU) == X86_VENDOR_Intel &&
 203  205              cpuid_getfamily(CPU) == 6 &&
 204  206              (cpuid_getmodel(CPU) == 0x2d || cpuid_getmodel(CPU) == 0x3e) &&
 205  207              is_x86_feature(x86_featureset, X86FSET_TSC)) {
 206  208                  (void) wrmsr(REG_TSC, 0UL);
 207  209          }
 208  210  
 209  211          /*
 210  212           * Patch the tsc_read routine with appropriate set of instructions,
 211  213           * depending on the processor family and architecure, to read the
 212  214           * time-stamp counter while ensuring no out-of-order execution.
 213  215           * Patch it while the kernel text is still writable.
 214  216           *
 215  217           * Note: tsc_read is not patched for intel processors whose family
 216  218           * is >6 and for amd whose family >f (in case they don't support rdtscp
 217  219           * instruction, unlikely). By default tsc_read will use cpuid for
 218  220           * serialization in such cases. The following code needs to be
 219  221           * revisited if intel processors of family >= f retains the
  
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 220  222           * instruction serialization nature of mfence instruction.
 221  223           * Note: tsc_read is not patched for x86 processors which do
 222  224           * not support "mfence". By default tsc_read will use cpuid for
 223  225           * serialization in such cases.
 224  226           *
 225  227           * The Xen hypervisor does not correctly report whether rdtscp is
 226  228           * supported or not, so we must assume that it is not.
 227  229           */
 228  230          if ((get_hwenv() & HW_XEN_HVM) == 0 &&
 229  231              is_x86_feature(x86_featureset, X86FSET_TSCP))
 230      -                patch_tsc_read(X86_HAVE_TSCP);
      232 +                patch_tsc_read(TSC_TSCP);
 231  233          else if (cpuid_getvendor(CPU) == X86_VENDOR_AMD &&
 232  234              cpuid_getfamily(CPU) <= 0xf &&
 233  235              is_x86_feature(x86_featureset, X86FSET_SSE2))
 234      -                patch_tsc_read(X86_TSC_MFENCE);
      236 +                patch_tsc_read(TSC_RDTSC_MFENCE);
 235  237          else if (cpuid_getvendor(CPU) == X86_VENDOR_Intel &&
 236  238              cpuid_getfamily(CPU) <= 6 &&
 237  239              is_x86_feature(x86_featureset, X86FSET_SSE2))
 238      -                patch_tsc_read(X86_TSC_LFENCE);
      240 +                patch_tsc_read(TSC_RDTSC_LFENCE);
 239  241  
 240  242  #endif  /* !__xpv */
 241  243  
 242  244  #if defined(__i386) && !defined(__xpv)
 243  245          /*
 244  246           * Some i386 processors do not implement the rdtsc instruction,
 245  247           * or at least they do not implement it correctly. Patch them to
 246  248           * return 0.
 247  249           */
 248  250          if (!is_x86_feature(x86_featureset, X86FSET_TSC))
 249      -                patch_tsc_read(X86_NO_TSC);
      251 +                patch_tsc_read(TSC_NONE);
 250  252  #endif  /* __i386 && !__xpv */
 251  253  
 252  254  #if defined(__amd64) && !defined(__xpv)
 253  255          patch_memops(cpuid_getvendor(CPU));
 254  256  #endif  /* __amd64 && !__xpv */
 255  257  
 256  258  #if !defined(__xpv)
 257  259          /* XXPV what, if anything, should be dorked with here under xen? */
 258  260  
 259  261          /*
 260  262           * While we're thinking about the TSC, let's set up %cr4 so that
 261  263           * userland can issue rdtsc, and initialize the TSC_AUX value
 262  264           * (the cpuid) for the rdtscp instruction on appropriately
 263  265           * capable hardware.
 264  266           */
 265  267          if (is_x86_feature(x86_featureset, X86FSET_TSC))
 266  268                  setcr4(getcr4() & ~CR4_TSD);
 267  269  
 268  270          if (is_x86_feature(x86_featureset, X86FSET_TSCP))
 269  271                  (void) wrmsr(MSR_AMD_TSCAUX, 0);
 270  272  
 271  273          /*
 272  274           * Let's get the other %cr4 stuff while we're here. Note, we defer
 273  275           * enabling CR4_SMAP until startup_end(); however, that's importantly
 274  276           * before we start other CPUs. That ensures that it will be synced out
 275  277           * to other CPUs.
 276  278           */
 277  279          if (is_x86_feature(x86_featureset, X86FSET_DE))
 278  280                  setcr4(getcr4() | CR4_DE);
 279  281  
 280  282          if (is_x86_feature(x86_featureset, X86FSET_SMEP))
 281  283                  setcr4(getcr4() | CR4_SMEP);
 282  284  #endif /* __xpv */
 283  285  
 284  286          /*
 285  287           * initialize t0
 286  288           */
 287  289          t0.t_stk = (caddr_t)rp - MINFRAME;
 288  290          t0.t_stkbase = t0stack;
 289  291          t0.t_pri = maxclsyspri - 3;
 290  292          t0.t_schedflag = TS_LOAD | TS_DONT_SWAP;
 291  293          t0.t_procp = &p0;
 292  294          t0.t_plockp = &p0lock.pl_lock;
 293  295          t0.t_lwp = &lwp0;
 294  296          t0.t_forw = &t0;
 295  297          t0.t_back = &t0;
 296  298          t0.t_next = &t0;
 297  299          t0.t_prev = &t0;
 298  300          t0.t_cpu = cpu[0];
 299  301          t0.t_disp_queue = &cpu0_disp;
 300  302          t0.t_bind_cpu = PBIND_NONE;
 301  303          t0.t_bind_pset = PS_NONE;
 302  304          t0.t_bindflag = (uchar_t)default_binding_mode;
 303  305          t0.t_cpupart = &cp_default;
 304  306          t0.t_clfuncs = &sys_classfuncs.thread;
 305  307          t0.t_copyops = NULL;
 306  308          THREAD_ONPROC(&t0, CPU);
 307  309  
 308  310          lwp0.lwp_thread = &t0;
 309  311          lwp0.lwp_regs = (void *)rp;
 310  312          lwp0.lwp_procp = &p0;
 311  313          t0.t_tid = p0.p_lwpcnt = p0.p_lwprcnt = p0.p_lwpid = 1;
 312  314  
 313  315          p0.p_exec = NULL;
 314  316          p0.p_stat = SRUN;
 315  317          p0.p_flag = SSYS;
 316  318          p0.p_tlist = &t0;
 317  319          p0.p_stksize = 2*PAGESIZE;
 318  320          p0.p_stkpageszc = 0;
 319  321          p0.p_as = &kas;
 320  322          p0.p_lockp = &p0lock;
 321  323          p0.p_brkpageszc = 0;
 322  324          p0.p_t1_lgrpid = LGRP_NONE;
 323  325          p0.p_tr_lgrpid = LGRP_NONE;
 324  326          sigorset(&p0.p_ignore, &ignoredefault);
 325  327  
 326  328          CPU->cpu_thread = &t0;
 327  329          bzero(&cpu0_disp, sizeof (disp_t));
 328  330          CPU->cpu_disp = &cpu0_disp;
 329  331          CPU->cpu_disp->disp_cpu = CPU;
 330  332          CPU->cpu_dispthread = &t0;
 331  333          CPU->cpu_idle_thread = &t0;
 332  334          CPU->cpu_flags = CPU_READY | CPU_RUNNING | CPU_EXISTS | CPU_ENABLE;
 333  335          CPU->cpu_dispatch_pri = t0.t_pri;
 334  336  
 335  337          CPU->cpu_id = 0;
 336  338  
 337  339          CPU->cpu_pri = 12;              /* initial PIL for the boot CPU */
 338  340  
 339  341          /*
 340  342           * The kernel doesn't use LDTs unless a process explicitly requests one.
 341  343           */
 342  344          p0.p_ldt_desc = null_sdesc;
 343  345  
 344  346          /*
 345  347           * Initialize thread/cpu microstate accounting
 346  348           */
 347  349          init_mstate(&t0, LMS_SYSTEM);
 348  350          init_cpu_mstate(CPU, CMS_SYSTEM);
 349  351  
 350  352          /*
 351  353           * Initialize lists of available and active CPUs.
 352  354           */
 353  355          cpu_list_init(CPU);
 354  356  
 355  357          pg_cpu_bootstrap(CPU);
 356  358  
 357  359          /*
 358  360           * Now that we have taken over the GDT, IDT and have initialized
 359  361           * active CPU list it's time to inform kmdb if present.
 360  362           */
 361  363          if (boothowto & RB_DEBUG)
 362  364                  kdi_idt_sync();
 363  365  
 364  366          /*
 365  367           * Explicitly set console to text mode (0x3) if this is a boot
 366  368           * post Fast Reboot, and the console is set to CONS_SCREEN_TEXT.
 367  369           */
 368  370          if (post_fastreboot && boot_console_type(NULL) == CONS_SCREEN_TEXT)
 369  371                  set_console_mode(0x3);
 370  372  
 371  373          /*
 372  374           * If requested (boot -d) drop into kmdb.
 373  375           *
 374  376           * This must be done after cpu_list_init() on the 64-bit kernel
 375  377           * since taking a trap requires that we re-compute gsbase based
 376  378           * on the cpu list.
 377  379           */
 378  380          if (boothowto & RB_DEBUGENTER)
 379  381                  kmdb_enter();
 380  382  
 381  383          cpu_vm_data_init(CPU);
 382  384  
 383  385          rp->r_fp = 0;   /* terminate kernel stack traces! */
 384  386  
 385  387          prom_init("kernel", (void *)NULL);
 386  388  
 387  389          /* User-set option overrides firmware value. */
 388  390          if (bootprop_getval(PLAT_DR_OPTIONS_NAME, &prop_value) == 0) {
 389  391                  plat_dr_options = (uint64_t)prop_value;
 390  392          }
 391  393  #if defined(__xpv)
 392  394          /* No support of DR operations on xpv */
 393  395          plat_dr_options = 0;
 394  396  #else   /* __xpv */
 395  397          /* Flag PLAT_DR_FEATURE_ENABLED should only be set by DR driver. */
 396  398          plat_dr_options &= ~PLAT_DR_FEATURE_ENABLED;
 397  399  #ifndef __amd64
 398  400          /* Only enable CPU/memory DR on 64 bits kernel. */
 399  401          plat_dr_options &= ~PLAT_DR_FEATURE_MEMORY;
 400  402          plat_dr_options &= ~PLAT_DR_FEATURE_CPU;
 401  403  #endif  /* __amd64 */
 402  404  #endif  /* __xpv */
 403  405  
 404  406          /*
 405  407           * Get value of "plat_dr_physmax" boot option.
 406  408           * It overrides values calculated from MSCT or SRAT table.
 407  409           */
 408  410          if (bootprop_getval(PLAT_DR_PHYSMAX_NAME, &prop_value) == 0) {
 409  411                  plat_dr_physmax = ((uint64_t)prop_value) >> PAGESHIFT;
 410  412          }
 411  413  
 412  414          /* Get value of boot_ncpus. */
 413  415          if (bootprop_getval(BOOT_NCPUS_NAME, &prop_value) != 0) {
 414  416                  boot_ncpus = NCPU;
 415  417          } else {
 416  418                  boot_ncpus = (int)prop_value;
 417  419                  if (boot_ncpus <= 0 || boot_ncpus > NCPU)
 418  420                          boot_ncpus = NCPU;
 419  421          }
 420  422  
 421  423          /*
 422  424           * Set max_ncpus and boot_max_ncpus to boot_ncpus if platform doesn't
 423  425           * support CPU DR operations.
 424  426           */
 425  427          if (plat_dr_support_cpu() == 0) {
 426  428                  max_ncpus = boot_max_ncpus = boot_ncpus;
 427  429          } else {
 428  430                  if (bootprop_getval(PLAT_MAX_NCPUS_NAME, &prop_value) != 0) {
 429  431                          max_ncpus = NCPU;
 430  432                  } else {
 431  433                          max_ncpus = (int)prop_value;
 432  434                          if (max_ncpus <= 0 || max_ncpus > NCPU) {
 433  435                                  max_ncpus = NCPU;
 434  436                          }
 435  437                          if (boot_ncpus > max_ncpus) {
 436  438                                  boot_ncpus = max_ncpus;
 437  439                          }
 438  440                  }
 439  441  
 440  442                  if (bootprop_getval(BOOT_MAX_NCPUS_NAME, &prop_value) != 0) {
 441  443                          boot_max_ncpus = boot_ncpus;
 442  444                  } else {
 443  445                          boot_max_ncpus = (int)prop_value;
 444  446                          if (boot_max_ncpus <= 0 || boot_max_ncpus > NCPU) {
 445  447                                  boot_max_ncpus = boot_ncpus;
 446  448                          } else if (boot_max_ncpus > max_ncpus) {
 447  449                                  boot_max_ncpus = max_ncpus;
 448  450                          }
 449  451                  }
 450  452          }
 451  453  
 452  454          /*
 453  455           * Initialize the lgrp framework
 454  456           */
 455  457          lgrp_init(LGRP_INIT_STAGE1);
 456  458  
 457  459          if (boothowto & RB_HALT) {
 458  460                  prom_printf("unix: kernel halted by -h flag\n");
 459  461                  prom_enter_mon();
 460  462          }
 461  463  
 462  464          ASSERT_STACK_ALIGNED();
 463  465  
 464  466          /*
 465  467           * Fill out cpu_ucode_info.  Update microcode if necessary.
 466  468           */
 467  469          ucode_check(CPU);
 468  470  
 469  471          if (workaround_errata(CPU) != 0)
 470  472                  panic("critical workaround(s) missing for boot cpu");
 471  473  }
 472  474  
 473  475  
 474  476  void
 475  477  mach_modpath(char *path, const char *filename)
 476  478  {
 477  479          /*
 478  480           * Construct the directory path from the filename.
 479  481           */
 480  482  
 481  483          int len;
 482  484          char *p;
 483  485          const char isastr[] = "/amd64";
 484  486          size_t isalen = strlen(isastr);
 485  487  
 486  488          len = strlen(SYSTEM_BOOT_PATH "/kernel");
 487  489          (void) strcpy(path, SYSTEM_BOOT_PATH "/kernel ");
 488  490          path += len + 1;
 489  491  
 490  492          if ((p = strrchr(filename, '/')) == NULL)
 491  493                  return;
 492  494  
 493  495          while (p > filename && *(p - 1) == '/')
 494  496                  p--;    /* remove trailing '/' characters */
 495  497          if (p == filename)
 496  498                  p++;    /* so "/" -is- the modpath in this case */
 497  499  
 498  500          /*
 499  501           * Remove optional isa-dependent directory name - the module
 500  502           * subsystem will put this back again (!)
 501  503           */
 502  504          len = p - filename;
 503  505          if (len > isalen &&
 504  506              strncmp(&filename[len - isalen], isastr, isalen) == 0)
 505  507                  p -= isalen;
 506  508  
 507  509          /*
 508  510           * "/platform/mumblefrotz" + " " + MOD_DEFPATH
 509  511           */
 510  512          len += (p - filename) + 1 + strlen(MOD_DEFPATH) + 1;
 511  513          (void) strncpy(path, filename, p - filename);
 512  514  }
  
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