| // 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, §size); |
| 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); |
| } |