blob: ede233955ced0ea29be514e8a1ab9c13b25f16d0 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2004-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "command.h"
#include "input.h"
#include <sys/mman.h>
#include "init.h"
#include "io.h"
#include <asm/mman.h>
static cmdinfo_t madvise_cmd;
static void
madvise_help(void)
{
printf(_(
"\n"
" advise the page cache about access patterns expected for a mapping\n"
"\n"
" Modifies page cache behavior when operating on the current mapping.\n"
" The range arguments are required by some advise commands ([*] below).\n"
" With no arguments, the POSIX_MADV_NORMAL advice is implied.\n"
" -d -- don't need these pages (POSIX_MADV_DONTNEED) [*]\n"
" -r -- expect random page references (POSIX_MADV_RANDOM)\n"
" -s -- expect sequential page references (POSIX_MADV_SEQUENTIAL)\n"
" -w -- will need these pages (POSIX_MADV_WILLNEED) [*]\n"
"\n"
"The following Linux-specific advise values are available:\n"
#ifdef MADV_COLLAPSE
" -c -- try to collapse range into transparent hugepages (MADV_COLLAPSE)\n"
#endif
#ifdef MADV_COLD
" -D -- deactivate the range (MADV_COLD)\n"
#endif
" -f -- free the range (MADV_FREE)\n"
" -h -- disable transparent hugepages (MADV_NOHUGEPAGE)\n"
" -H -- enable transparent hugepages (MADV_HUGEPAGE)\n"
" -m -- mark the range mergeable (MADV_MERGEABLE)\n"
" -M -- mark the range unmergeable (MADV_UNMERGEABLE)\n"
" -o -- mark the range offline (MADV_SOFT_OFFLINE)\n"
" -p -- punch a hole in the file (MADV_REMOVE)\n"
" -P -- poison the page cache (MADV_HWPOISON)\n"
#ifdef MADV_POPULATE_READ
" -R -- prefault in the range for read (MADV_POPULATE_READ)\n"
#endif
#ifdef MADV_POPULATE_WRITE
" -W -- prefault in the range for write (MADV_POPULATE_WRITE)\n"
#endif
#ifdef MADV_PAGEOUT
" -X -- reclaim the range (MADV_PAGEOUT)\n"
#endif
" Notes:\n"
" NORMAL sets the default readahead setting on the file.\n"
" RANDOM sets the readahead setting on the file to zero.\n"
" SEQUENTIAL sets double the default readahead setting on the file.\n"
" WILLNEED forces the maximum readahead.\n"
"\n"));
}
static int
madvise_f(
int argc,
char **argv)
{
off_t offset, llength;
size_t length;
void *start;
int advise = MADV_NORMAL, c;
size_t blocksize, sectsize;
while ((c = getopt(argc, argv, "cdDfhHmMopPrRswWX")) != EOF) {
switch (c) {
#ifdef MADV_COLLAPSE
case 'c': /* collapse to thp */
advise = MADV_COLLAPSE;
break;
#endif
case 'd': /* Don't need these pages */
advise = MADV_DONTNEED;
break;
#ifdef MADV_COLD
case 'D': /* make more likely to be reclaimed */
advise = MADV_COLD;
break;
#endif
case 'f': /* page range out of memory */
advise = MADV_FREE;
break;
case 'h': /* enable thp memory */
advise = MADV_HUGEPAGE;
break;
case 'H': /* disable thp memory */
advise = MADV_NOHUGEPAGE;
break;
case 'm': /* enable merging */
advise = MADV_MERGEABLE;
break;
case 'M': /* disable merging */
advise = MADV_UNMERGEABLE;
break;
case 'o': /* offline */
advise = MADV_SOFT_OFFLINE;
break;
case 'p': /* punch hole */
advise = MADV_REMOVE;
break;
case 'P': /* poison */
advise = MADV_HWPOISON;
break;
case 'r': /* Expect random page references */
advise = MADV_RANDOM;
break;
#ifdef MADV_POPULATE_READ
case 'R': /* fault in pages for read */
advise = MADV_POPULATE_READ;
break;
#endif
case 's': /* Expect sequential page references */
advise = MADV_SEQUENTIAL;
break;
case 'w': /* Will need these pages */
advise = MADV_WILLNEED;
break;
#ifdef MADV_POPULATE_WRITE
case 'W': /* fault in pages for write */
advise = MADV_POPULATE_WRITE;
break;
#endif
#ifdef MADV_PAGEOUT
case 'X': /* reclaim memory */
advise = MADV_PAGEOUT;
break;
#endif
default:
exitcode = 1;
return command_usage(&madvise_cmd);
}
}
if (optind == argc) {
offset = mapping->offset;
length = mapping->length;
} else if (optind == argc - 2) {
init_cvtnum(&blocksize, &sectsize);
offset = cvtnum(blocksize, sectsize, argv[optind]);
if (offset < 0) {
printf(_("non-numeric offset argument -- %s\n"),
argv[optind]);
exitcode = 1;
return 0;
}
optind++;
llength = cvtnum(blocksize, sectsize, argv[optind]);
if (llength < 0) {
printf(_("non-numeric length argument -- %s\n"),
argv[optind]);
exitcode = 1;
return 0;
} else if (llength > (size_t)llength) {
printf(_("length argument too large -- %lld\n"),
(long long)llength);
exitcode = 1;
return 0;
} else
length = (size_t)llength;
} else {
exitcode = 1;
return command_usage(&madvise_cmd);
}
start = check_mapping_range(mapping, offset, length, 1);
if (!start) {
exitcode = 1;
return 0;
}
if (madvise(start, length, advise) < 0) {
perror("madvise");
exitcode = 1;
return 0;
}
return 0;
}
void
madvise_init(void)
{
madvise_cmd.name = "madvise";
madvise_cmd.altname = "ma";
madvise_cmd.cfunc = madvise_f;
madvise_cmd.argmin = 0;
madvise_cmd.argmax = -1;
madvise_cmd.flags = CMD_NOFILE_OK | CMD_FOREIGN_OK;
madvise_cmd.args = _("[-drsw] [off len]");
madvise_cmd.oneline = _("give advice about use of memory");
madvise_cmd.help = madvise_help;
add_command(&madvise_cmd);
}