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2009-01-22MERGE-via-pending-tracking-hist-MERGE-via-stable-tracking-MERGE-via-mokopatc ↵merge
hes-tracking-fix-stray-endmenu-patch-1232632040-1232632141 pending-tracking-hist top was MERGE-via-stable-tracking-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040-1232632141 / fdf777a63bcb59e0dfd78bfe2c6242e01f6d4eb9 ... parent commitmessage: From: merge <null@invalid> MERGE-via-stable-tracking-hist-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040 stable-tracking-hist top was MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040 / 90463bfd2d5a3c8b52f6e6d71024a00e052b0ced ... parent commitmessage: From: merge <null@invalid> MERGE-via-mokopatches-tracking-hist-fix-stray-endmenu-patch mokopatches-tracking-hist top was fix-stray-endmenu-patch / 3630e0be570de8057e7f8d2fe501ed353cdf34e6 ... parent commitmessage: From: Andy Green <andy@openmoko.com> fix-stray-endmenu.patch Signed-off-by: Andy Green <andy@openmoko.com>
2008-10-20mlock: make mlock error return Posixly CorrectLee Schermerhorn
Rework Posix error return for mlock(). Posix requires error code for mlock*() system calls for some conditions that differ from what kernel low level functions, such as get_user_pages(), return for those conditions. For more info, see: http://marc.info/?l=linux-kernel&m=121750892930775&w=2 This patch provides the same translation of get_user_pages() error codes to posix specified error codes in the context of the mlock rework for unevictable lru. [akpm@linux-foundation.org: fix build] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20vmstat: mlocked pages statisticsNick Piggin
Add NR_MLOCK zone page state, which provides a (conservative) count of mlocked pages (actually, the number of mlocked pages moved off the LRU). Reworked by lts to fit in with the modified mlock page support in the Reclaim Scalability series. [kosaki.motohiro@jp.fujitsu.com: fix incorrect Mlocked field of /proc/meminfo] [lee.schermerhorn@hp.com: mlocked-pages: add event counting with statistics] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20mmap: handle mlocked pages during map, remap, unmapRik van Riel
Originally by Nick Piggin <npiggin@suse.de> Remove mlocked pages from the LRU using "unevictable infrastructure" during mmap(), munmap(), mremap() and truncate(). Try to move back to normal LRU lists on munmap() when last mlocked mapping removed. Remove PageMlocked() status when page truncated from file. [akpm@linux-foundation.org: cleanup] [kamezawa.hiroyu@jp.fujitsu.com: fix double unlock_page()] [kosaki.motohiro@jp.fujitsu.com: split LRU: munlock rework] [lee.schermerhorn@hp.com: mlock: fix __mlock_vma_pages_range comment block] [akpm@linux-foundation.org: remove bogus kerneldoc token] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: KAMEZAWA Hiroyuki <kamewzawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20mlock: downgrade mmap sem while populating mlocked regionsLee Schermerhorn
We need to hold the mmap_sem for write to initiatate mlock()/munlock() because we may need to merge/split vmas. However, this can lead to very long lock hold times attempting to fault in a large memory region to mlock it into memory. This can hold off other faults against the mm [multithreaded tasks] and other scans of the mm, such as via /proc. To alleviate this, downgrade the mmap_sem to read mode during the population of the region for locking. This is especially the case if we need to reclaim memory to lock down the region. We [probably?] don't need to do this for unlocking as all of the pages should be resident--they're already mlocked. Now, the caller's of the mlock functions [mlock_fixup() and mlock_vma_pages_range()] expect the mmap_sem to be returned in write mode. Changing all callers appears to be way too much effort at this point. So, restore write mode before returning. Note that this opens a window where the mmap list could change in a multithreaded process. So, at least for mlock_fixup(), where we could be called in a loop over multiple vmas, we check that a vma still exists at the start address and that vma still covers the page range [start,end). If not, we return an error, -EAGAIN, and let the caller deal with it. Return -EAGAIN from mlock_vma_pages_range() function and mlock_fixup() if the vma at 'start' disappears or changes so that the page range [start,end) is no longer contained in the vma. Again, let the caller deal with it. Looks like only sys_remap_file_pages() [via mmap_region()] should actually care. With this patch, I no longer see processes like ps(1) blocked for seconds or minutes at a time waiting for a large [multiple gigabyte] region to be locked down. However, I occassionally see delays while unlocking or unmapping a large mlocked region. Should we also downgrade the mmap_sem for the unlock path? Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20mlock: mlocked pages are unevictableNick Piggin
Make sure that mlocked pages also live on the unevictable LRU, so kswapd will not scan them over and over again. This is achieved through various strategies: 1) add yet another page flag--PG_mlocked--to indicate that the page is locked for efficient testing in vmscan and, optionally, fault path. This allows early culling of unevictable pages, preventing them from getting to page_referenced()/try_to_unmap(). Also allows separate accounting of mlock'd pages, as Nick's original patch did. Note: Nick's original mlock patch used a PG_mlocked flag. I had removed this in favor of the PG_unevictable flag + an mlock_count [new page struct member]. I restored the PG_mlocked flag to eliminate the new count field. 2) add the mlock/unevictable infrastructure to mm/mlock.c, with internal APIs in mm/internal.h. This is a rework of Nick's original patch to these files, taking into account that mlocked pages are now kept on unevictable LRU list. 3) update vmscan.c:page_evictable() to check PageMlocked() and, if vma passed in, the vm_flags. Note that the vma will only be passed in for new pages in the fault path; and then only if the "cull unevictable pages in fault path" patch is included. 4) add try_to_unlock() to rmap.c to walk a page's rmap and ClearPageMlocked() if no other vmas have it mlocked. Reuses as much of try_to_unmap() as possible. This effectively replaces the use of one of the lru list links as an mlock count. If this mechanism let's pages in mlocked vmas leak through w/o PG_mlocked set [I don't know that it does], we should catch them later in try_to_unmap(). One hopes this will be rare, as it will be relatively expensive. Original mm/internal.h, mm/rmap.c and mm/mlock.c changes: Signed-off-by: Nick Piggin <npiggin@suse.de> splitlru: introduce __get_user_pages(): New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS. because current get_user_pages() can't grab PROT_NONE pages theresore it cause PROT_NONE pages can't munlock. [akpm@linux-foundation.org: fix this for pagemap-pass-mm-into-pagewalkers.patch] [akpm@linux-foundation.org: untangle patch interdependencies] [akpm@linux-foundation.org: fix things after out-of-order merging] [hugh@veritas.com: fix page-flags mess] [lee.schermerhorn@hp.com: fix munlock page table walk - now requires 'mm'] [kosaki.motohiro@jp.fujitsu.com: build fix] [kosaki.motohiro@jp.fujitsu.com: fix truncate race and sevaral comments] [kosaki.motohiro@jp.fujitsu.com: splitlru: introduce __get_user_pages()] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-04mlock() fix return valuesKOSAKI Motohiro
Halesh says: Please find the below testcase provide to test mlock. Test Case : =========================== #include <sys/resource.h> #include <stdio.h> #include <sys/stat.h> #include <sys/types.h> #include <unistd.h> #include <sys/mman.h> #include <fcntl.h> #include <errno.h> #include <stdlib.h> int main(void) { int fd,ret, i = 0; char *addr, *addr1 = NULL; unsigned int page_size; struct rlimit rlim; if (0 != geteuid()) { printf("Execute this pgm as root\n"); exit(1); } /* create a file */ if ((fd = open("mmap_test.c",O_RDWR|O_CREAT,0755)) == -1) { printf("cant create test file\n"); exit(1); } page_size = sysconf(_SC_PAGE_SIZE); /* set the MEMLOCK limit */ rlim.rlim_cur = 2000; rlim.rlim_max = 2000; if ((ret = setrlimit(RLIMIT_MEMLOCK,&rlim)) != 0) { printf("Cant change limit values\n"); exit(1); } addr = 0; while (1) { /* map a page into memory each time*/ if ((addr = (char *) mmap(addr,page_size, PROT_READ | PROT_WRITE,MAP_SHARED,fd,0)) == MAP_FAILED) { printf("cant do mmap on file\n"); exit(1); } if (0 == i) addr1 = addr; i++; errno = 0; /* lock the mapped memory pagewise*/ if ((ret = mlock((char *)addr, 1500)) == -1) { printf("errno value is %d\n", errno); printf("cant lock maped region\n"); exit(1); } addr = addr + page_size; } } ====================================================== This testcase results in an mlock() failure with errno 14 that is EFAULT, but it has nowhere been specified that mlock() will return EFAULT. When I tested the same on older kernels like 2.6.18, I got the correct result i.e errno 12 (ENOMEM). I think in source code mlock(2), setting errno ENOMEM has been missed in do_mlock() , on mlock_fixup() failure. SUSv3 requires the following behavior frmo mlock(2). [ENOMEM] Some or all of the address range specified by the addr and len arguments does not correspond to valid mapped pages in the address space of the process. [EAGAIN] Some or all of the memory identified by the operation could not be locked when the call was made. This rule isn't so nice and slighly strange. but many people think POSIX/SUS compliance is important. Reported-by: Halesh Sadashiv <halesh.sadashiv@ap.sony.com> Tested-by: Halesh Sadashiv <halesh.sadashiv@ap.sony.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16do not limit locked memory when RLIMIT_MEMLOCK is RLIM_INFINITYHerbert van den Bergh
Fix a bug in mm/mlock.c on 32-bit architectures that prevents a user from locking more than 4GB of shared memory, or allocating more than 4GB of shared memory in hugepages, when rlim[RLIMIT_MEMLOCK] is set to RLIM_INFINITY. Signed-off-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Acked-by: Chris Mason <chris.mason@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-21Detach sched.h from mm.hAlexey Dobriyan
First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-07[PATCH] mlock cleanupRik Bobbaers
mm is defined as vma->vm_mm, so use that. Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11[PATCH] move capable() to capability.hRandy.Dunlap
- Move capable() from sched.h to capability.h; - Use <linux/capability.h> where capable() is used (in include/, block/, ipc/, kernel/, a few drivers/, mm/, security/, & sound/; many more drivers/ to go) Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!