pagein-0.00.03/0000755000175000017500000000000013056624537011572 5ustar kingkingpagein-0.00.03/Makefile0000644000175000017500000000330513056624523013226 0ustar kingking# # Copyright (C) 2016-2017 Canonical, Ltd. # # This program is free software; you can redistribute it and/or # modify it under the terms of the GNU General Public License # as published by the Free Software Foundation; either version 2 # of the License, or (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. # VERSION=0.00.03 CFLAGS += -Wall -Wextra -DVERSION='"$(VERSION)"' -O2 # # Pedantic flags # ifeq ($(PEDANTIC),1) CFLAGS += -Wabi -Wcast-qual -Wfloat-equal -Wmissing-declarations \ -Wmissing-format-attribute -Wno-long-long -Wpacked \ -Wredundant-decls -Wshadow -Wno-missing-field-initializers \ -Wno-missing-braces -Wno-sign-compare -Wno-multichar endif export DEB_BUILD_HARDENING=1 BINDIR=/usr/bin MANDIR=/usr/share/man/man1 pagein: pagein.o $(CC) $(CPPFLAGS) $(CFLAGS) $< -o $@ $(LDFLAGS) pagein.1.gz: pagein.1 gzip -c $< > $@ dist: rm -rf pagein-$(VERSION) mkdir pagein-$(VERSION) cp -rp Makefile pagein.c pagein.1 COPYING snapcraft \ pagein-$(VERSION) tar -zcf pagein-$(VERSION).tar.gz pagein-$(VERSION) rm -rf pagein-$(VERSION) clean: rm -f pagein pagein.o pagein.1.gz rm -f pagein-$(VERSION).tar.gz install: pagein pagein.1.gz mkdir -p ${DESTDIR}${BINDIR} cp pagein ${DESTDIR}${BINDIR} mkdir -p ${DESTDIR}${MANDIR} cp pagein.1.gz ${DESTDIR}${MANDIR} pagein-0.00.03/pagein.10000644000175000017500000000450613056624523013117 0ustar kingking.\" Hey, EMACS: -*- nroff -*- .\" First parameter, NAME, should be all caps .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection .\" other parameters are allowed: see man(7), man(1) .TH PAGEIN 1 "9 January, 2017" .\" Please adjust this date whenever revising the manpage. .\" .\" Some roff macros, for reference: .\" .nh disable hyphenation .\" .hy enable hyphenation .\" .ad l left justify .\" .ad b justify to both left and right margins .\" .nf disable filling .\" .fi enable filling .\" .br insert line break .\" .sp insert n+1 empty lines .\" for manpage-specific macros, see man(7) .SH NAME pagein \- a tool to force swapped out pages back into memory .br .SH SYNOPSIS .B pagein .RI [ \-a ] .RI [ \-h ] .RI [ \-p\ pid ] .RI [ \-t ] .RI [ \-v ] .br .SH DESCRIPTION Pagein is a tool that forces pages that are in swap to be paged in back to memory. The main usecase for pagein is to exercise the VM and swap subsystems for testing purposes. .SH OPTIONS pagein options are as follow: .TP .B \-a try to page in all processes. This needs to be run with root privilege to allow pagein to access all the processes. Cannot be used with the \-p option. .TP .B \-h show help information. .TP .B \-p pid page in process with process ID pid. Cannot be used with the \-a option. Processes not owned by the user need to be paged in by running pagein with root privilege. .TP .B \-t attach, page-in pages and then detach on each process being paged in using ptrace. In theory this will stop an active process and hence won't allow it to change memory mappings during the paging in phase. .TP .B \-v verbose mode, shows progress and paging in statistics, useful with the \-a option. .SH EXAMPLES .LP Page in all processes and show progress: .RS 8 sudo pagein \-a \-v .RE .LP Page in the compiz process: .RS 8 sudo pagein \-p $(pidof compiz) .RE .SH SEE ALSO .BR free (1) .SH AUTHOR pagein was written by Colin King .PP This manual page was written by Colin King , for the Ubuntu project (but may be used by others). .SH COPYRIGHT Copyright \(co 2016-2017 Canonical Ltd. .br This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. pagein-0.00.03/pagein.c0000644000175000017500000002730113056624523013177 0ustar kingking/* * Copyright (C) 2016-2017 Canonical, Ltd. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define APP_NAME "pagein" #define PAGE_4K (4096) #define OPT_VERBOSE (0x00000001) #define OPT_ALL (0x00000002) #define OPT_BY_PID (0x00000004) #define OPT_TRACE_ATTACH (0x00000008) #define GOT_MEMFREE (0x01) #define GOT_SWAPFREE (0x02) #define GOT_ALL (GOT_MEMFREE | GOT_SWAPFREE) static uint16_t opt_flags = 0; typedef struct mapping { uint64_t begin; uint64_t end; char *path; struct mapping *next; } mapping_t; /* * get_page_size() * get page size */ static int32_t get_page_size(void) { int32_t page_size; #ifdef _SC_PAGESIZE int32_t sz; sz = sysconf(_SC_PAGESIZE); page_size = (sz <= 0) ? PAGE_4K : sz; #else page_size = PAGE_4K; #endif return page_size; } /* * get_memstats() * get some pertinent memory statistics from /proc/meminfo */ static int get_memstats(int64_t *memfree, int64_t *swapfree) { FILE *fp; char buffer[4096]; uint8_t got = 0; *memfree = 0; *swapfree = 0; fp = fopen("/proc/meminfo", "r"); if (!fp) return -errno; while (fgets(buffer, sizeof(buffer), fp)) { if ((strstr(buffer, "MemFree:")) && (sscanf(buffer, "%*s %" SCNd64, memfree) == 1)) { got |= GOT_MEMFREE; continue; } if ((strstr(buffer, "SwapFree:")) && (sscanf(buffer, "%*s %" SCNd64, swapfree) == 1)) { got |= GOT_SWAPFREE; } if ((got & GOT_ALL) == GOT_ALL) break; } fclose(fp); return 0; } /* * show_help() * show command help info */ static void show_help(void) { printf(APP_NAME ":\n"); printf("Usage: " APP_NAME " [OPTION [ARG]]\n"); printf("-a\tpage in pages in all processes\n"); printf("-h\tshow help\n"); printf("-p pid\tpull in pages on specified process\n"); printf("-t\tattach/detatch using ptrace each process being paged in\n"); printf("-v\tverbose mode\n"); printf("Note: to page in all processes, run with root privilege\n"); } /* * free_pagein_mappings() * free mappings information */ static void free_pagein_mappings(mapping_t *mappings) { mapping_t *mapping, *next = NULL; for (mapping = mappings; mapping; mapping = next) { next = mapping->next; free(mapping->path); free(mapping); } } /* * get_pagein_mappings() * get all the mappings that pagein uses */ static mapping_t *get_pagein_mappings(void) { FILE *fpmap; mapping_t *mappings = NULL; char buffer[4096]; fpmap = fopen("/proc/self/maps", "r"); if (!fpmap) return NULL; while (fgets(buffer, sizeof(buffer), fpmap)) { mapping_t *mapping; uint64_t begin, end; char path[1024]; if (sscanf(buffer, "%" SCNx64 "-%" SCNx64 " %*s %*x %*x:%*x %*d %1023s", &begin, &end, path) != 3) continue; if ((begin >= end) || (begin == end)) continue; mapping = malloc(sizeof(*mapping)); if (!mapping) goto nomem; mapping->path = strdup(path); if (!mapping->path) { free(mapping); goto nomem; } mapping->begin = begin; mapping->end = end; mapping->next = mappings; mappings = mapping; } (void)fclose(fpmap); return mappings; nomem: (void)fclose(fpmap); free_pagein_mappings(mappings); return NULL; } /* * in_pagein() * is the mapping also in the pagein process space? */ static bool in_pagein(const mapping_t *mappings, uint64_t begin, uint64_t end, char *path) { const mapping_t *mapping; for (mapping = mappings; mapping; mapping = mapping->next) { if (!strcmp(mapping->path, path)) return true; if ((begin < mapping->begin && end < mapping->begin) || (begin > mapping->end && end > mapping->end)) continue; return true; } return false; } /* * pagein_proc_mmap() * try to mmap and touch pages */ static void *pagein_proc_mmap( const mapping_t *mappings, const int32_t page_size, const uint64_t begin, const uint64_t end, char *path, char *prot, size_t *pages_touched) { int fd; int prot_flags; struct stat statbuf; void *mapped; uint64_t off; if (*path != '/') return NULL; if (in_pagein(mappings, begin, end, path)) return NULL; if ((fd = open(path, O_RDONLY | O_NONBLOCK)) < 0) return NULL; if (fstat(fd, &statbuf) < 0) goto err; if (!(S_ISREG(statbuf.st_mode))) goto err; prot_flags = 0; if (index(prot, 'r')) prot_flags |= PROT_READ; if (index(prot, 'w')) prot_flags |= PROT_WRITE; if (index(prot, 'x')) prot_flags |= PROT_EXEC; if (!prot_flags) goto err; mapped = mmap((void *)(ptrdiff_t)begin, end - begin, prot_flags, MAP_FIXED | MAP_PRIVATE | MAP_POPULATE, fd, 0); if (mapped == MAP_FAILED) goto err; (void)madvise((void*)(ptrdiff_t)begin, end - begin, MADV_WILLNEED); if (prot_flags & PROT_READ) { unsigned char x = 0; for (off = begin; off < end; off += page_size) { volatile char *ptr = (volatile char *)off; x += *ptr; (*pages_touched)++; } } (void)close(fd); return mapped; err: (void)close(fd); return NULL; } /* * pagein_proc() * try to force page in pages for a specific process */ static int pagein_proc( const mapping_t *mappings, const int32_t page_size, const pid_t pid, int32_t *const procs, int32_t *const kthreads, int64_t *const total_pages_touched) { char path[PATH_MAX]; char buffer[4096]; int fdmem, rc = 0; FILE *fpmap; uint64_t begin, end; size_t pages = 0, pages_touched = 0; bool has_maps = false; if (pid == getpid()) return 0; if (opt_flags & OPT_TRACE_ATTACH) { int ret; ret = ptrace(PTRACE_ATTACH, pid, NULL, NULL); if (ret < 0) return -errno; (void)waitpid(pid, NULL, 0); } snprintf(path, sizeof(path), "/proc/%d/mem", pid); fdmem = open(path, O_RDONLY); if (fdmem < 0) { rc = -errno; goto err; } snprintf(path, sizeof(path), "/proc/%d/maps", pid); fpmap = fopen(path, "r"); if (!fpmap) { (void)close(fdmem); rc = -errno; goto err; } /* * Look for field 0060b000-0060c000 r--p 0000b000 08:01 1901726 */ while (fgets(buffer, sizeof(buffer), fpmap)) { uint64_t off; uint8_t byte; void *mapped = NULL; char path[1024]; char prot[5]; if (sscanf(buffer, "%" SCNx64 "-%" SCNx64 " %5s %*x %*x:%*x %*d %1023s", &begin, &end, prot, path) != 4) continue; if ((begin >= end) || (begin == end)) continue; mapped = pagein_proc_mmap(mappings, page_size, begin, end, path, prot, &pages_touched); has_maps = true; for (off = begin; off < end; off += page_size, pages++) { unsigned char vec; /* In core? no need to touch */ if (mapped && (mincore((void*)(ptrdiff_t)off, 1, &vec) == 0) && (vec & 1)) continue; if (lseek(fdmem, off, SEEK_SET) == (off_t)-1) continue; if (read(fdmem, &byte, sizeof(byte)) == sizeof(byte)) pages_touched++; } if (mapped) { (void)munmap((void *)(ptrdiff_t)begin, end - begin); } } /* * Kernel threads don't have maps, so don't * count these in the stats */ if (has_maps) { *procs += 1; *total_pages_touched += pages_touched; } else { *kthreads += 1; } if (opt_flags & OPT_VERBOSE) { printf("PID:%5d, %12zu pages, %12" PRId64 " pages touched\r", pid, pages, *total_pages_touched); fflush(stdout); } (void)fclose(fpmap); (void)close(fdmem); err: if (opt_flags & OPT_TRACE_ATTACH) { (void)ptrace(PTRACE_DETACH, pid, NULL, NULL); } return rc; } /* * pagein_all_procs() * attempt to page in all processes */ static int pagein_all_procs( const mapping_t *mappings, const int32_t page_size, int32_t *const procs, int32_t *const kthreads, int32_t *const total_procs, int64_t *const total_pages_touched) { DIR *dp; struct dirent *d; dp = opendir("/proc"); if (!dp) return -1; while ((d = readdir(dp)) != NULL) { pid_t pid; if (isdigit(d->d_name[0]) && sscanf(d->d_name, "%d", &pid) == 1) { *total_procs += 1; pagein_proc(mappings, page_size, pid, procs, kthreads, total_pages_touched); } } (void)closedir(dp); return 0; } int main(int argc, char **argv) { int64_t memfree_begin, memfree_end; int64_t swapfree_begin, swapfree_end; int64_t delta; int64_t total_pages_touched = 0ULL; int32_t procs = 0, total_procs = 0, kthreads = 0; const int32_t page_size = get_page_size(); const int32_t scale = page_size / 1024; struct rusage usage; pid_t pid = -1; mapping_t *mappings; for (;;) { int c = getopt(argc, argv, "adhp:tv"); if (c == -1) break; switch (c) { case 'a': opt_flags |= OPT_ALL; break; case 'h': show_help(); exit(EXIT_SUCCESS); break; case 'p': opt_flags |= OPT_BY_PID; pid = atoi(optarg); if (pid < 1) { fprintf(stderr, "bad pid: %d\n", pid); exit(EXIT_FAILURE); } break; case 't': opt_flags |= OPT_TRACE_ATTACH; break; case 'v': opt_flags |= OPT_VERBOSE; break; default: show_help(); exit(EXIT_FAILURE); } } if ((opt_flags & (OPT_ALL | OPT_BY_PID)) == (OPT_ALL | OPT_BY_PID)) { fprintf(stderr, "must not use -a and -p options together\n"); exit(EXIT_FAILURE); } if ((opt_flags & (OPT_ALL | OPT_BY_PID)) == 0) { fprintf(stderr, "must use one of -a or -p, use -h for more details\n"); exit(EXIT_FAILURE); } mappings = get_pagein_mappings(); if (!mappings) { fprintf(stderr, "cannot read pagein's own mappings\n"); exit(EXIT_FAILURE); } get_memstats(&memfree_begin, &swapfree_begin); if (opt_flags & OPT_ALL) pagein_all_procs(mappings, page_size, &procs, &kthreads, &total_procs, &total_pages_touched); if (opt_flags & OPT_BY_PID) { int ret; ret = pagein_proc(mappings, page_size, pid, &procs, &kthreads, &total_pages_touched); if (ret < 0) { fprintf(stderr, "cannot page in PID %d errno = %d (%s)\n", pid, -ret, strerror(-ret)); fprintf(stderr, " Note: this is normally because of ptrace PTRACE_MODE_ATTACH_FSCREDS access\n"); fprintf(stderr, " mode failure of pagein. pagein needs to be run with the CAP_SYS_PTRACE\n"); fprintf(stderr, " capability (for example, run pagein as root).\n"); free_pagein_mappings(mappings); exit(EXIT_FAILURE); } } get_memstats(&memfree_end, &swapfree_end); if (opt_flags & OPT_VERBOSE) printf("%-60.60s\r", ""); if (opt_flags & OPT_ALL) { printf("Processes scanned: %" PRIu32 "\n", total_procs); printf("Kernel threads: %" PRIu32 " (skipped)\n", kthreads); printf("Processes touched: %" PRIu32 "\n", procs); } printf("Pages touched: %" PRIu64 "\n", total_pages_touched); delta = memfree_begin - memfree_end; printf("Free memory decrease: %" PRId64 "K (%" PRId64 " pages)\n", delta, delta / scale); delta = swapfree_begin - swapfree_end; printf("Swap memory decrease: %" PRId64 "K (%" PRId64 " pages)\n", delta, delta / scale); if (getrusage(RUSAGE_SELF, &usage) == 0) { printf("Page faults major: %lu\n", usage.ru_majflt); printf("Page faults minor: %lu\n", usage.ru_minflt); printf("Swaps: %lu\n", usage.ru_nswap); } free_pagein_mappings(mappings); return EXIT_SUCCESS; } pagein-0.00.03/snapcraft/0000755000175000017500000000000013056624523013546 5ustar kingkingpagein-0.00.03/snapcraft/snapcraft.yaml0000644000175000017500000000075413056624523016421 0ustar kingkingname: pagein version: 0.00.00-20170109-1-5-a404278 summary: tool to force swapped out pages back into memory description: Pagein is a tool that forces pages that are in swap to be paged in back to memory. The main usecase for pagein is to exercise the VM and swap subsystems for testing purposes. confinement: devmode parts: pagein: plugin: make source: .. build-packages: - gcc - make apps: pagein: command: usr/bin/pagein pagein-0.00.03/snapcraft/Makefile0000644000175000017500000000101713056624523015205 0ustar kingkingVERSION=$(shell git tag | tail -1 | cut -c2-) COMMITS=$(shell git log --oneline | wc -l) SHA=$(shell git log -1 --oneline | cut -d' ' -f1) DATE=$(shell date +'%Y%m%d-1') V=$(VERSION)-$(DATE)-$(COMMITS)-$(SHA) all: set_version snapcraft set_version: cat snapcraft.yaml | sed 's/version: .*/version: $(V)/' > snapcraft-tmp.yaml mv snapcraft-tmp.yaml snapcraft.yaml clean: rm -rf setup *.snap snapcraft clean cat snapcraft.yaml | sed 's/version: .*/version: 0/' > snapcraft-tmp.yaml mv snapcraft-tmp.yaml snapcraft.yaml pagein-0.00.03/COPYING0000644000175000017500000004325413056624523012630 0ustar kingking GNU GENERAL PUBLIC LICENSE Version 2, June 1991 Copyright (C) 1989, 1991 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 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If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License. 9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation. 10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally. NO WARRANTY 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. END OF TERMS AND CONDITIONS How to Apply These Terms to Your New Programs If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. Copyright (C) This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Also add information on how to contact you by electronic and paper mail. If the program is interactive, make it output a short notice like this when it starts in an interactive mode: Gnomovision version 69, Copyright (C) year name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. , 1 April 1989 Ty Coon, President of Vice This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License.