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* disable sys_timerfd() for 2.6.23Andrew Morton2007-09-191-0/+1
| | | | | | | | | | | | | | | There is still some confusion and disagreement over what this interface should actually do. So it is best that we disable it in 2.6.23 until we get that fully sorted out. (sys_timerfd() was present in 2.6.22 but it was apparently broken, so here we assume that nobody is using it yet). Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Davide Libenzi <davidel@xmailserver.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Kconfig: remove top level menu "Code maturity level options"Al Boldi2007-07-311-4/+1
| | | | | | | | | | | | Remove the top level menu "Code maturity level options", and moves its options into menu "General setup". This makes Kconfig less cluttered and easier to setup. Signed-off-by: Al Boldi <a1426z@gawab.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ANON_INODES shouldn't be user visibleAdrian Bunk2007-07-311-11/+5
| | | | | | | | | | There doesn't seem to be a good reason for ANON_INODES being an user visible option. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sh: Add sh to the CC_OPTIMIZE_FOR_SIZE dependencies.Paul Mundt2007-07-261-1/+1
| | | | | | | Presently we only use this with CONFIG_EXPERIMENTAL, but it is something that can be supported commonly. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* Make SLUB the default allocatorChristoph Lameter2007-07-171-1/+1
| | | | | | | | | | | There are some reports that 2.6.22 has SLUB as the default. Not true! This will make SLUB the default for 2.6.23. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* user namespace: add the frameworkCedric Le Goater2007-07-161-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Basically, it will allow a process to unshare its user_struct table, resetting at the same time its own user_struct and all the associated accounting. A new root user (uid == 0) is added to the user namespace upon creation. Such root users have full privileges and it seems that theses privileges should be controlled through some means (process capabilities ?) The unshare is not included in this patch. Changes since [try #4]: - Updated get_user_ns and put_user_ns to accept NULL, and get_user_ns to return the namespace. Changes since [try #3]: - moved struct user_namespace to files user_namespace.{c,h} Changes since [try #2]: - removed struct user_namespace* argument from find_user() Changes since [try #1]: - removed struct user_namespace* argument from find_user() - added a root_user per user namespace Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: Andrew Morgan <agm@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* remove CONFIG_UTS_NS and CONFIG_IPC_NSCedric Le Goater2007-07-161-17/+0
| | | | | | | | | | | | | | CONFIG_UTS_NS and CONFIG_IPC_NS have very little value as they only deactivate the unshare of the uts and ipc namespaces and do not improve performance. Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Acked-by: "Serge E. Hallyn" <serue@us.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Pavel Emelianov <xemul@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Use menuconfig objects II - module menuJan Engelhardt2007-07-161-4/+1
| | | | | | | | | | Change menuconfig objects from "menu, config" into "menuconfig" so that the user can disable the whole feature without entering its menu first. Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* slob: sparsemem supportPaul Mundt2007-07-161-1/+1
| | | | | | | | | | | | | | | Currently slob is disabled if we're using sparsemem, due to an earlier patch from Goto-san. Slob and static sparsemem work without any trouble as it is, and the only hiccup is a missing slab_is_available() in the case of sparsemem extreme. With this, we're rid of the last set of restrictions for slob usage. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Matt Mackall <mpm@selenic.com> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* block/Kconfig already has its own "menuconfig" so remove theseJan Engelhardt2007-07-101-2/+0
| | | | | | | | | "menu, endmenu" that did not get cleaned up in the block patch [ http://lkml.org/lkml/2007/4/10/251 ] Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* SLUB: Remove depends on EXPERIMENTAL and !ARCH_USES_SLAB_PAGE_STRUCTChristoph Lameter2007-05-171-1/+0
| | | | | | | | | | | | | No arch sets ARCH_USES_SLAB_PAGE_STRUCT anymore. Remove the experimental dependency as well since we want to have it as a real alternative to SLAB. It all comes down to killing a single line from init/Kconfig. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* slob: implement RCU freeingNick Piggin2007-05-171-5/+2
| | | | | | | | | | | The SLOB allocator should implement SLAB_DESTROY_BY_RCU correctly, because even on UP, RCU freeing semantics are not equivalent to simply freeing immediately. This also allows SLOB to be used on SMP. Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signal/timer/event: eventfd coreDavide Libenzi2007-05-111-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a very simple and light file descriptor, that can be used as event wait/dispatch by userspace (both wait and dispatch) and by the kernel (dispatch only). It can be used instead of pipe(2) in all cases where those would simply be used to signal events. Their kernel overhead is much lower than pipes, and they do not consume two fds. When used in the kernel, it can offer an fd-bridge to enable, for example, functionalities like KAIO or syslets/threadlets to signal to an fd the completion of certain operations. But more in general, an eventfd can be used by the kernel to signal readiness, in a POSIX poll/select way, of interfaces that would otherwise be incompatible with it. The API is: int eventfd(unsigned int count); The eventfd API accepts an initial "count" parameter, and returns an eventfd fd. It supports poll(2) (POLLIN, POLLOUT, POLLERR), read(2) and write(2). The POLLIN flag is raised when the internal counter is greater than zero. The POLLOUT flag is raised when at least a value of "1" can be written to the internal counter. The POLLERR flag is raised when an overflow in the counter value is detected. The write(2) operation can never overflow the counter, since it blocks (unless O_NONBLOCK is set, in which case -EAGAIN is returned). But the eventfd_signal() function can do it, since it's supposed to not sleep during its operation. The read(2) function reads the __u64 counter value, and reset the internal value to zero. If the value read is equal to (__u64) -1, an overflow happened on the internal counter (due to 2^64 eventfd_signal() posts that has never been retired - unlickely, but possible). The write(2) call writes an __u64 count value, and adds it to the current counter. The eventfd fd supports O_NONBLOCK also. On the kernel side, we have: struct file *eventfd_fget(int fd); int eventfd_signal(struct file *file, unsigned int n); The eventfd_fget() should be called to get a struct file* from an eventfd fd (this is an fget() + check of f_op being an eventfd fops pointer). The kernel can then call eventfd_signal() every time it wants to post an event to userspace. The eventfd_signal() function can be called from any context. An eventfd() simple test and bench is available here: http://www.xmailserver.org/eventfd-bench.c This is the eventfd-based version of pipetest-4 (pipe(2) based): http://www.xmailserver.org/pipetest-4.c Not that performance matters much in the eventfd case, but eventfd-bench shows almost as double as performance than pipetest-4. [akpm@linux-foundation.org: fix i386 build] [akpm@linux-foundation.org: add sys_eventfd to sys_ni.c] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signal/timer/event: timerfd coreDavide Libenzi2007-05-111-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a new system call for timers events delivered though file descriptors. This allows timer event to be used with standard POSIX poll(2), select(2) and read(2). As a consequence of supporting the Linux f_op->poll subsystem, they can be used with epoll(2) too. The system call is defined as: int timerfd(int ufd, int clockid, int flags, const struct itimerspec *utmr); The "ufd" parameter allows for re-use (re-programming) of an existing timerfd w/out going through the close/open cycle (same as signalfd). If "ufd" is -1, s new file descriptor will be created, otherwise the existing "ufd" will be re-programmed. The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME. The time specified in the "utmr->it_value" parameter is the expiry time for the timer. If the TFD_TIMER_ABSTIME flag is set in "flags", this is an absolute time, otherwise it's a relative time. If the time specified in the "utmr->it_interval" is not zero (.tv_sec == 0, tv_nsec == 0), this is the period at which the following ticks should be generated. The "utmr->it_interval" should be set to zero if only one tick is requested. Setting the "utmr->it_value" to zero will disable the timer, or will create a timerfd without the timer enabled. The function returns the new (or same, in case "ufd" is a valid timerfd descriptor) file, or -1 in case of error. As stated before, the timerfd file descriptor supports poll(2), select(2) and epoll(2). When a timer event happened on the timerfd, a POLLIN mask will be returned. The read(2) call can be used, and it will return a u32 variable holding the number of "ticks" that happened on the interface since the last call to read(2). The read(2) call supportes the O_NONBLOCK flag too, and EAGAIN will be returned if no ticks happened. A quick test program, shows timerfd working correctly on my amd64 box: http://www.xmailserver.org/timerfd-test.c [akpm@linux-foundation.org: add sys_timerfd to sys_ni.c] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signal/timer/event: signalfd coreDavide Libenzi2007-05-111-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch series implements the new signalfd() system call. I took part of the original Linus code (and you know how badly it can be broken :), and I added even more breakage ;) Signals are fetched from the same signal queue used by the process, so signalfd will compete with standard kernel delivery in dequeue_signal(). If you want to reliably fetch signals on the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This seems to be working fine on my Dual Opteron machine. I made a quick test program for it: http://www.xmailserver.org/signafd-test.c The signalfd() system call implements signal delivery into a file descriptor receiver. The signalfd file descriptor if created with the following API: int signalfd(int ufd, const sigset_t *mask, size_t masksize); The "ufd" parameter allows to change an existing signalfd sigmask, w/out going to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new signalfd file. The "mask" allows to specify the signal mask of signals that we are interested in. The "masksize" parameter is the size of "mask". The signalfd fd supports the poll(2) and read(2) system calls. The poll(2) will return POLLIN when signals are available to be dequeued. As a direct consequence of supporting the Linux poll subsystem, the signalfd fd can use used together with epoll(2) too. The read(2) system call will return a "struct signalfd_siginfo" structure in the userspace supplied buffer. The return value is the number of bytes copied in the supplied buffer, or -1 in case of error. The read(2) call can also return 0, in case the sighand structure to which the signalfd was attached, has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will return -EAGAIN in case no signal is available. If the size of the buffer passed to read(2) is lower than sizeof(struct signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also return -ERESTARTSYS in case a signal hits the process. The format of the struct signalfd_siginfo is, and the valid fields depends of the (->code & __SI_MASK) value, in the same way a struct siginfo would: struct signalfd_siginfo { __u32 signo; /* si_signo */ __s32 err; /* si_errno */ __s32 code; /* si_code */ __u32 pid; /* si_pid */ __u32 uid; /* si_uid */ __s32 fd; /* si_fd */ __u32 tid; /* si_fd */ __u32 band; /* si_band */ __u32 overrun; /* si_overrun */ __u32 trapno; /* si_trapno */ __s32 status; /* si_status */ __s32 svint; /* si_int */ __u64 svptr; /* si_ptr */ __u64 utime; /* si_utime */ __u64 stime; /* si_stime */ __u64 addr; /* si_addr */ }; [akpm@linux-foundation.org: fix signalfd_copyinfo() on i386] Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* signal/timer/event fds: anonymous inode sourceDavide Libenzi2007-05-111-0/+10
| | | | | | | | | | | | | This patch add an anonymous inode source, to be used for files that need and inode only in order to create a file*. We do not care of having an inode for each file, and we do not even care of having different names in the associated dentries (dentry names will be same for classes of file*). This allow code reuse, and will be used by epoll, signalfd and timerfd (and whatever else there'll be). Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB: SLUB_DEBUG must depend on SLUBChristoph Lameter2007-05-101-0/+1
| | | | | | | | | Otherwise people get asked about SLUB_DEBUG even if they have another slab allocator enabled. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2007-05-091-4/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits) sound: convert "sound" subdirectory to UTF-8 MAINTAINERS: Add cxacru website/mailing list include files: convert "include" subdirectory to UTF-8 general: convert "kernel" subdirectory to UTF-8 documentation: convert the Documentation directory to UTF-8 Convert the toplevel files CREDITS and MAINTAINERS to UTF-8. remove broken URLs from net drivers' output Magic number prefix consistency change to Documentation/magic-number.txt trivial: s/i_sem /i_mutex/ fix file specification in comments drivers/base/platform.c: fix small typo in doc misc doc and kconfig typos Remove obsolete fat_cvf help text Fix occurrences of "the the " Fix minor typoes in kernel/module.c Kconfig: Remove reference to external mqueue library Kconfig: A couple of grammatical fixes in arch/i386/Kconfig Correct comments in genrtc.c to refer to correct /proc file. Fix more "deprecated" spellos. Fix "deprecated" typoes. ... Fix trivial comment conflict in kernel/relay.c.
| * Kconfig: Remove reference to external mqueue libraryRobert P. J. Day2007-05-091-3/+1
| | | | | | | | | | | | | | | | Remove the reference to an external mqueue library since that was merged into glibc in 2004. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
| * Fix trivial typos in Kconfig* filesDavid Sterba2007-05-091-1/+1
| | | | | | | | | | | | | | Fix several typos in help text in Kconfig* files. Signed-off-by: David Sterba <dave@jikos.cz> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* | Fix spellings of slab allocator section in init/KconfigChristoph Lameter2007-05-091-8/+7
| | | | | | | | | | | | | | | | | | | | Fix some of the spelling issues. Fix sentences. Discourage SLOB use since SLUB can pack objects denser. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | SLUB: add CONFIG_SLUB_DEBUGChristoph Lameter2007-05-091-0/+9
|/ | | | | | | | | | | | | | | | | CONFIG_SLUB_DEBUG can be used to switch off the debugging and sysfs components of SLUB. Thus SLUB will be able to replace SLOB. SLUB can arrange objects in a denser way than SLOB and the code size should be minimal without debugging and sysfs support. Note that CONFIG_SLUB_DEBUG is materially different from CONFIG_SLAB_DEBUG. CONFIG_SLAB_DEBUG is used to enable slab debugging in SLAB. SLUB enables debugging via a boot parameter. SLUB debug code should always be present. CONFIG_SLUB_DEBUG can be modified in the embedded config section. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Move LOG_BUF_SHIFT to a more sensible placeAlistair John Strachan2007-05-081-0/+17
| | | | | | | | | | | | | | | | | Several people have observed that perhaps LOG_BUF_SHIFT should be in a more obvious place than under DEBUG_KERNEL. Under some circumstances (such as the PARISC architecture), DEBUG_KERNEL can increase kernel size, which is an undesirable trade off for something as trivial as increasing the kernel log buffer size. Instead, move LOG_BUF_SHIFT into "General Setup", so that people are more likely to be able to change it such a circumstance that the default buffer size is insufficient. Signed-off-by: Alistair John Strachan <s0348365@sms.ed.ac.uk> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* blackfin architectureBryan Wu2007-05-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds support for the Analog Devices Blackfin processor architecture, and currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561 (Dual Core) devices, with a variety of development platforms including those avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP, BF561-EZKIT), and Bluetechnix! Tinyboards. The Blackfin architecture was jointly developed by Intel and Analog Devices Inc. (ADI) as the Micro Signal Architecture (MSA) core and introduced it in December of 2000. Since then ADI has put this core into its Blackfin processor family of devices. The Blackfin core has the advantages of a clean, orthogonal,RISC-like microprocessor instruction set. It combines a dual-MAC (Multiply/Accumulate), state-of-the-art signal processing engine and single-instruction, multiple-data (SIMD) multimedia capabilities into a single instruction-set architecture. The Blackfin architecture, including the instruction set, is described by the ADSP-BF53x/BF56x Blackfin Processor Programming Reference http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf The Blackfin processor is already supported by major releases of gcc, and there are binary and source rpms/tarballs for many architectures at: http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete documentation, including "getting started" guides available at: http://docs.blackfin.uclinux.org/ which provides links to the sources and patches you will need in order to set up a cross-compiling environment for bfin-linux-uclibc This patch, as well as the other patches (toolchain, distribution, uClibc) are actively supported by Analog Devices Inc, at: http://blackfin.uclinux.org/ We have tested this on LTP, and our test plan (including pass/fails) can be found at: http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel [m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files] Signed-off-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl> Signed-off-by: Aubrey Li <aubrey.li@analog.com> Signed-off-by: Jie Zhang <jie.zhang@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB coreChristoph Lameter2007-05-071-13/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a new slab allocator which was motivated by the complexity of the existing code in mm/slab.c. It attempts to address a variety of concerns with the existing implementation. A. Management of object queues A particular concern was the complex management of the numerous object queues in SLAB. SLUB has no such queues. Instead we dedicate a slab for each allocating CPU and use objects from a slab directly instead of queueing them up. B. Storage overhead of object queues SLAB Object queues exist per node, per CPU. The alien cache queue even has a queue array that contain a queue for each processor on each node. For very large systems the number of queues and the number of objects that may be caught in those queues grows exponentially. On our systems with 1k nodes / processors we have several gigabytes just tied up for storing references to objects for those queues This does not include the objects that could be on those queues. One fears that the whole memory of the machine could one day be consumed by those queues. C. SLAB meta data overhead SLAB has overhead at the beginning of each slab. This means that data cannot be naturally aligned at the beginning of a slab block. SLUB keeps all meta data in the corresponding page_struct. Objects can be naturally aligned in the slab. F.e. a 128 byte object will be aligned at 128 byte boundaries and can fit tightly into a 4k page with no bytes left over. SLAB cannot do this. D. SLAB has a complex cache reaper SLUB does not need a cache reaper for UP systems. On SMP systems the per CPU slab may be pushed back into partial list but that operation is simple and does not require an iteration over a list of objects. SLAB expires per CPU, shared and alien object queues during cache reaping which may cause strange hold offs. E. SLAB has complex NUMA policy layer support SLUB pushes NUMA policy handling into the page allocator. This means that allocation is coarser (SLUB does interleave on a page level) but that situation was also present before 2.6.13. SLABs application of policies to individual slab objects allocated in SLAB is certainly a performance concern due to the frequent references to memory policies which may lead a sequence of objects to come from one node after another. SLUB will get a slab full of objects from one node and then will switch to the next. F. Reduction of the size of partial slab lists SLAB has per node partial lists. This means that over time a large number of partial slabs may accumulate on those lists. These can only be reused if allocator occur on specific nodes. SLUB has a global pool of partial slabs and will consume slabs from that pool to decrease fragmentation. G. Tunables SLAB has sophisticated tuning abilities for each slab cache. One can manipulate the queue sizes in detail. However, filling the queues still requires the uses of the spin lock to check out slabs. SLUB has a global parameter (min_slab_order) for tuning. Increasing the minimum slab order can decrease the locking overhead. The bigger the slab order the less motions of pages between per CPU and partial lists occur and the better SLUB will be scaling. G. Slab merging We often have slab caches with similar parameters. SLUB detects those on boot up and merges them into the corresponding general caches. This leads to more effective memory use. About 50% of all caches can be eliminated through slab merging. This will also decrease slab fragmentation because partial allocated slabs can be filled up again. Slab merging can be switched off by specifying slub_nomerge on boot up. Note that merging can expose heretofore unknown bugs in the kernel because corrupted objects may now be placed differently and corrupt differing neighboring objects. Enable sanity checks to find those. H. Diagnostics The current slab diagnostics are difficult to use and require a recompilation of the kernel. SLUB contains debugging code that is always available (but is kept out of the hot code paths). SLUB diagnostics can be enabled via the "slab_debug" option. Parameters can be specified to select a single or a group of slab caches for diagnostics. This means that the system is running with the usual performance and it is much more likely that race conditions can be reproduced. I. Resiliency If basic sanity checks are on then SLUB is capable of detecting common error conditions and recover as best as possible to allow the system to continue. J. Tracing Tracing can be enabled via the slab_debug=T,<slabcache> option during boot. SLUB will then protocol all actions on that slabcache and dump the object contents on free. K. On demand DMA cache creation. Generally DMA caches are not needed. If a kmalloc is used with __GFP_DMA then just create this single slabcache that is needed. For systems that have no ZONE_DMA requirement the support is completely eliminated. L. Performance increase Some benchmarks have shown speed improvements on kernbench in the range of 5-10%. The locking overhead of slub is based on the underlying base allocation size. If we can reliably allocate larger order pages then it is possible to increase slub performance much further. The anti-fragmentation patches may enable further performance increases. Tested on: i386 UP + SMP, x86_64 UP + SMP + NUMA emulation, IA64 NUMA + Simulator SLUB Boot options slub_nomerge Disable merging of slabs slub_min_order=x Require a minimum order for slab caches. This increases the managed chunk size and therefore reduces meta data and locking overhead. slub_min_objects=x Mininum objects per slab. Default is 8. slub_max_order=x Avoid generating slabs larger than order specified. slub_debug Enable all diagnostics for all caches slub_debug=<options> Enable selective options for all caches slub_debug=<o>,<cache> Enable selective options for a certain set of caches Available Debug options F Double Free checking, sanity and resiliency R Red zoning P Object / padding poisoning U Track last free / alloc T Trace all allocs / frees (only use for individual slabs). To use SLUB: Apply this patch and then select SLUB as the default slab allocator. [hugh@veritas.com: fix an oops-causing locking error] [akpm@linux-foundation.org: various stupid cleanups and small fixes] Signed-off-by: Christoph Lameter <clameter@sgi.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>
* kbuild: clarify the creation of the LOCALVERSION_AUTO string.Robert P. J. Day2007-05-021-6/+10
| | | | | | | | | Clarify the creation of the LOCALVERSION_AUTO string during kernel configuration, and fix a couple typoes while we're there. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
* [PATCH] initramfs should not depend on CONFIG_BLOCKDimitri Gorokhovik2007-03-061-0/+16
| | | | | | | | | | | | | | | | | initramfs ended up depending on BLOCK: INITRAMFS_SOURCE <-- BLK_DEV_INITRD <-- BLOCK This inhibits use of customized-initramfs-over-ramfs without block layer (ramfs would still be enabled), useful in embedded applications. Move BLK_DEV_INITRD out of 'drivers/block/Kconfig' and into 'init/Kconfig', make it unconditional. Signed-off-by: Dimitri Gorokhovik <dimitri.gorokhovik@free.fr> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] sysctl: move SYSV IPC sysctls to their own fileEric W. Biederman2007-02-141-0/+6
| | | | | | | | | | | | | | | This is just a simple cleanup to keep kernel/sysctl.c from getting to crowded with special cases, and by keeping all of the ipc logic to together it makes the code a little more readable. [gcoady.lk@gmail.com: build fix] Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Grant Coady <gcoady.lk@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Move TASK_XACCT, TASK_IO_ACCOUNTING up in menusAlexey Dobriyan2007-02-111-18/+18
| | | | | | | | | Since they depends on TASKSTATS, it would be nice to move them closer to another options depending on TASKSTATS. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] disable init/initramfs.cJean-Paul Saman2007-02-111-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The file init/initramfs.c is always compiled and linked in the kernel vmlinux even when BLK_DEV_RAM and BLK_DEV_INITRD are disabled and the system isn't using any form of an initramfs or initrd. In this situation the code is only used to unpack a (static) default initial rootfilesystem. The current init/initramfs.c code. usr/initramfs_data.o compiles to a size of ~15 kbytes. Disabling BLK_DEV_RAM and BLK_DEV_INTRD shrinks the kernel code size with ~60 Kbytes. This patch avoids compiling in the code and data for initramfs support if CONFIG_BLK_DEV_INITRD is not defined. Instead of the initramfs code and data it uses a small routine in init/noinitramfs.c to setup an initial static default environment for mounting a rootfilesystem later on in the kernel initialisation process. The new code is: 164 bytes of size. The patch is separated in two parts: 1) doesn't compile initramfs code when CONFIG_BLK_DEV_INITRD is not set 2) changing all plaforms vmlinux.lds.S files to not reserve an area of PAGE_SIZE when CONFIG_BLK_DEV_INITRD is not set. [deweerdt@free.fr: warning fix] Signed-off-by: Jean-Paul Saman <jean-paul.saman@nxp.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] handle SLOB with sparsemenYasunori Goto2006-12-221-1/+1
| | | | | | | | | | | This is to disallow to make SLOB with SMP or SPARSEMEM. This avoids latent troubles of SLOB with SLAB_DESTROY_BY_RCU. And fix compile error. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] CONFIG_VM_EVENT_COUNTER comment decrustifyPaul Jackson2006-12-221-4/+4
| | | | | | | | | | | | | | | | The VM event counters, enabled by CONFIG_VM_EVENT_COUNTERS, which provides VM event counters in /proc/vmstat, has become more essential to non-EMBEDDED kernel configurations than they were in the past. Comments in the code and the Kconfig configuration explanation were stale, downplaying their role excessively. Refresh those comments to correctly reflect the current role of VM event counters. Signed-off-by: Paul Jackson <pj@sgi.com> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Kconfig: fix spelling error in config KALLSYMS help textJesper Juhl2006-12-121-1/+1
| | | | | | Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Acked-By: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] io-accounting: core statisticsAndrew Morton2006-12-101-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The present per-task IO accounting isn't very useful. It simply counts the number of bytes passed into read() and write(). So if a process reads 1MB from an already-cached file, it is accused of having performed 1MB of I/O, which is wrong. (David Wright had some comments on the applicability of the present logical IO accounting: For billing purposes it is useless but for workload analysis it is very useful read_bytes/read_calls average read request size write_bytes/write_calls average write request size read_bytes/read_blocks ie logical/physical can indicate hit rate or thrashing write_bytes/write_blocks ie logical/physical guess since pdflush writes can be missed I often look for logical larger than physical to see filesystem cache problems. And the bytes/cpusec can help find applications that are dominating the cache and causing slow interactive response from page cache contention. I want to find the IO intensive applications and make sure they are doing efficient IO. Thus the acctcms(sysV) or csacms command would give the high IO commands). This patchset adds new accounting which tries to be more accurate. We account for three things: reads: attempt to count the number of bytes which this process really did cause to be fetched from the storage layer. Done at the submit_bio() level, so it is accurate for block-backed filesystems. I also attempt to wire up NFS and CIFS. writes: attempt to count the number of bytes which this process caused to be sent to the storage layer. This is done at page-dirtying time. The big inaccuracy here is truncate. If a process writes 1MB to a file and then deletes the file, it will in fact perform no writeout. But it will have been accounted as having caused 1MB of write. So... cancelled_writes: account the number of bytes which this process caused to not happen, by truncating pagecache. We _could_ just subtract this from the process's `write' accounting. But that means that some processes would be reported to have done negative amounts of write IO, which is silly. So we just report the raw number and punt this decision up to userspace. Now, we _could_ account for writes at the physical I/O level. But - This would require that we track memory-dirtying tasks at the per-page level (would require a new pointer in struct page). - It would mean that IO statistics for a process are usually only available long after that process has exitted. Which means that we probably cannot communicate this info via taskstats. This patch: Wire up the kernel-private data structures and the accessor functions to manipulate them. Cc: Jay Lan <jlan@sgi.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Chris Sturtivant <csturtiv@sgi.com> Cc: Tony Ernst <tee@sgi.com> Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net> Cc: David Wright <daw@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* CONFIG_SYSFS_DEPRECATEDKay Sievers2006-12-011-0/+20
| | | | | | | | | | | | Provide a way to support older versions of udev that are shipped in older distros. If this option is disabled, it will also turn off the compatible symlinks in sysfs that older programs might rely on. When in doubt, or if running a distro older than 2006, say Yes here. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] sysctl: Undeprecate sys_sysctlEric W. Biederman2006-11-081-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The basic issue is that despite have been deprecated and warned about as a very bad thing in the man pages since its inception there are a few real users of sys_sysctl. It was my assumption that because sysctl had been deprecated for all of 2.6 there would be no user space users by this point, so I initially gave sys_sysctl a very short deprecation period. Now that I know there are a few real users the only sane way to proceed with deprecation is to push the time limit out to a year or two work and work with distributions that have big testing pools like fedora core to find these last remaining users. Which means that the sys_sysctl interface needs to be maintained in the meantime. Since I have provided a technical measure that allows us to add new sysctl entries without reserving more binary numbers I believe that is enough to fix the sys_sysctl binary interface maintenance problems, because there is no longer a need to change the binary interface at all. Since the sys_sysctl implementation needs to stay around for a while and the worst of the maintenance issues that caused us to occasionally break the ABI have been addressed I don't see any advantage in continuing with the removal of sys_sysctl. So instead of merely increasing the deprecation period this patch removes the deprecation of sys_sysctl and modifies the kernel to compile the code in by default. With committing to maintain sys_sysctl we get all of the advantages of a fast interface for anything that needs it. Currently sys_sysctl is about 5x faster than /proc/sys, for the same string data. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] uml: use DEFCONFIG_LIST to avoid reading host's configPaolo 'Blaisorblade' Giarrusso2006-10-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This should make sure that, for UML, host's configuration files are not considered, which avoids various pains to the user. Our dependency are such that the obtained Kconfig will be valid and will lead to successful compilation - however they cannot prevent an user from disabling any boot device, and if an option is not set in the read .config (say /boot/config-XXX), with make menuconfig ARCH=um, it is not set. This always disables UBD and all console I/O channels, which leads to non-working UML kernels, so this bothers users - especially now, since it will happen on almost every machine (/boot/config-`uname -r` exists almost on every machine). It can be workarounded with make defconfig ARCH=um, but it is non-obvious and can be avoided, so please _do_ merge this patch. Given the existence of options, it could be interesting to implement (additionally) "option required" - with it, Kconfig will refuse reading a .config file (from wherever it comes) if the given option is not set. With this, one could mark with it the option characteristic of the given architecture (it was an old proposal of Roman Zippel, when I pointed out our problem): config UML option required default y However this should be further discussed: *) for x86, it must support constructs like: ==arch/i386/Kconfig== config 64BIT option required default n where Kconfig must require that CONFIG_64BIT is disabled or not present in the read .config. *) do we want to do such checks only for the starting defconfig or also for .config? Which leads to: *) I may want to port a x86_64 .config to x86 and viceversa, or even among more different archs. Should that be allowed, and in which measure (the user may force skipping the check for a .config or it is only given a warning by default)? Cc: Roman Zippel <zippel@linux-m68k.org> Cc: <kbuild-devel@lists.sourceforge.net> Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] IPC namespace coreKirill Korotaev2006-10-021-0/+9
| | | | | | | | | | | | | | | | | | | | | This patch set allows to unshare IPCs and have a private set of IPC objects (sem, shm, msg) inside namespace. Basically, it is another building block of containers functionality. This patch implements core IPC namespace changes: - ipc_namespace structure - new config option CONFIG_IPC_NS - adds CLONE_NEWIPC flag - unshare support [clg@fr.ibm.com: small fix for unshare of ipc namespace] [akpm@osdl.org: build fix] Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: Kirill Korotaev <dev@openvz.org> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] namespaces: utsname: implement utsname namespacesSerge E. Hallyn2006-10-021-0/+8
| | | | | | | | | | | | | | | | | | This patch defines the uts namespace and some manipulators. Adds the uts namespace to task_struct, and initializes a system-wide init namespace. It leaves a #define for system_utsname so sysctl will compile. This define will be removed in a separate patch. [akpm@osdl.org: build fix, cleanup] Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] csa: Extended system accounting over taskstatsJay Lan2006-10-011-0/+9
| | | | | | | | | | | | | | | Add extended system accounting handling over taskstats interface. A CONFIG_TASK_XACCT flag is created to enable the extended accounting code. Signed-off-by: Jay Lan <jlan@sgi.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Chris Sturtivant <csturtiv@sgi.com> Cc: Tony Ernst <tee@sgi.com> Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix EMBEDDED + SYSCTL menuRandy Dunlap2006-10-011-7/+7
| | | | | | | | | | | SYSCTL should still depend on EMBEDDED. This unbreaks the EMBEDDED menu (from the recent SYSCTL_SYCALL menu option patch). Fix typos in new SYSCTL_SYSCALL menu. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] allow /proc/config.gz to be built as a moduleRoss Biro2006-10-011-1/+1
| | | | | | | | | | | | | | | | | | The driver for /proc/config.gz consumes rather a lot of memory and it is in fact possible to build it as a module. In some ways this is a bit risky, because the .config which is used for compiling kernel/configs.c isn't necessarily the same as the .config which was used to build vmlinux. But OTOH the potential memory savings are decent, and it'd be fairly dumb to build your configs.o with a different .config. Signed-off-by: Andrew Morton <akpm@google.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] BLOCK: Make it possible to disable the block layer [try #6]David Howells2006-09-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible to disable the block layer. Not all embedded devices require it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require the block layer to be present. This patch does the following: (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev support. (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls an item that uses the block layer. This includes: (*) Block I/O tracing. (*) Disk partition code. (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS. (*) The SCSI layer. As far as I can tell, even SCSI chardevs use the block layer to do scheduling. Some drivers that use SCSI facilities - such as USB storage - end up disabled indirectly from this. (*) Various block-based device drivers, such as IDE and the old CDROM drivers. (*) MTD blockdev handling and FTL. (*) JFFS - which uses set_bdev_super(), something it could avoid doing by taking a leaf out of JFFS2's book. (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is, however, still used in places, and so is still available. (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and parts of linux/fs.h. (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK. (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK. (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK is not enabled. (*) fs/no-block.c is created to hold out-of-line stubs and things that are required when CONFIG_BLOCK is not set: (*) Default blockdev file operations (to give error ENODEV on opening). (*) Makes some /proc changes: (*) /proc/devices does not list any blockdevs. (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK. (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK. (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if given command other than Q_SYNC or if a special device is specified. (*) In init/do_mounts.c, no reference is made to the blockdev routines if CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2. (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return error ENOSYS by way of cond_syscall if so). (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if CONFIG_BLOCK is not set, since they can't then happen. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* [PATCH] sysctl: Allow /proc/sys without sys_sysctlEric W. Biederman2006-09-271-14/+17
| | | | | | | | | | | Since sys_sysctl is deprecated start allow it to be compiled out. This should catch any remaining user space code that cares, and paves the way for further sysctl cleanups. [akpm@osdl.org: If sys_sysctl() is not compiled-in, emit a warning] Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Kconfig: move CONFIG_EMBEDDED options to submenuChuck Ebbert2006-09-161-28/+28
| | | | | | | | | | | | | | | | | | Fix two problems with the CONFIG_EMBEDDED submenu: (1) The menu was split in two by the rt_mutex patch, which moved half the items into the "General setup" menu. (2) CONFIG_SYSCTL and CONFIG_UID16 were added to the main menu instead of the submenu. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] per-task-delay-accounting: delay accounting usage of taskstats interfaceShailabh Nagar2006-07-141-0/+1
| | | | | | | | | | | | | | Usage of taskstats interface by delay accounting. Signed-off-by: Shailabh Nagar <nagar@us.ibm.com> Signed-off-by: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Peter Chubb <peterc@gelato.unsw.edu.au> Cc: Erich Focht <efocht@ess.nec.de> Cc: Levent Serinol <lserinol@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] per-task-delay-accounting: taskstats interfaceShailabh Nagar2006-07-141-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | Create a "taskstats" interface based on generic netlink (NETLINK_GENERIC family), for getting statistics of tasks and thread groups during their lifetime and when they exit. The interface is intended for use by multiple accounting packages though it is being created in the context of delay accounting. This patch creates the interface without populating the fields of the data that is sent to the user in response to a command or upon the exit of a task. Each accounting package interested in using taskstats has to provide an additional patch to add its stats to the common structure. [akpm@osdl.org: cleanups, Kconfig fix] Signed-off-by: Shailabh Nagar <nagar@us.ibm.com> Signed-off-by: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Peter Chubb <peterc@gelato.unsw.edu.au> Cc: Erich Focht <efocht@ess.nec.de> Cc: Levent Serinol <lserinol@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] per-task-delay-accounting: setupShailabh Nagar2006-07-141-0/+10
| | | | | | | | | | | | | | | | | | Initialization code related to collection of per-task "delay" statistics which measure how long it had to wait for cpu, sync block io, swapping etc. The collection of statistics and the interface are in other patches. This patch sets up the data structures and allows the statistics collection to be disabled through a kernel boot parameter. Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Peter Chubb <peterc@gelato.unsw.edu.au> Cc: Erich Focht <efocht@ess.nec.de> Cc: Levent Serinol <lserinol@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] UML: fix the INIT_ENV_ARG_LIMIT dependenciesAdrian Bunk2006-06-301-2/+2
| | | | | | | | | | | | | Fix the INIT_ENV_ARG_LIMIT dependencies to what seems to have been intended. Spotted by Jean-Luc Leger. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Light weight event countersChristoph Lameter2006-06-301-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The remaining counters in page_state after the zoned VM counter patches have been applied are all just for show in /proc/vmstat. They have no essential function for the VM. We use a simple increment of per cpu variables. In order to avoid the most severe races we disable preempt. Preempt does not prevent the race between an increment and an interrupt handler incrementing the same statistics counter. However, that race is exceedingly rare, we may only loose one increment or so and there is no requirement (at least not in kernel) that the vm event counters have to be accurate. In the non preempt case this results in a simple increment for each counter. For many architectures this will be reduced by the compiler to a single instruction. This single instruction is atomic for i386 and x86_64. And therefore even the rare race condition in an interrupt is avoided for both architectures in most cases. The patchset also adds an off switch for embedded systems that allows a building of linux kernels without these counters. The implementation of these counters is through inline code that hopefully results in only a single instruction increment instruction being emitted (i386, x86_64) or in the increment being hidden though instruction concurrency (EPIC architectures such as ia64 can get that done). Benefits: - VM event counter operations usually reduce to a single inline instruction on i386 and x86_64. - No interrupt disable, only preempt disable for the preempt case. Preempt disable can also be avoided by moving the counter into a spinlock. - Handling is similar to zoned VM counters. - Simple and easily extendable. - Can be omitted to reduce memory use for embedded use. References: RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=113512330605497&w=2 RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=114988082814934&w=2 local_t http://marc.theaimsgroup.com/?l=linux-kernel&m=114991748606690&w=2 V2 http://marc.theaimsgroup.com/?t=115014808400007&r=1&w=2 V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767022346&w=2 V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115047968808926&w=2 Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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