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* [PATCH] lockdep: fix printk recursion logicIngo Molnar2006-10-111-9/+2
| | | | | | | | | | | | | | | | | | | | Bug reported and fixed by Tilman Schmidt <tilman@imap.cc>: if lockdep is enabled then log messages make it to /var/log/messages belatedly. The reason is a missed wakeup of klogd. Initially there was only a lockdep_internal() protection against lockdep recursion within vprintk() - it grew the 'outer' lockdep_off()/on() protection only later on. But that lockdep_off() made the release_console_sem() within vprintk() always happen under the lockdep_internal() condition, causing the bug. The right solution to remove the inner protection against recursion here - the outer one is enough. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] lockdep: use BUILD_BUG_ONAlexey Dobriyan2006-10-111-4/+1
| | | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] bitmap: parse input from kernel and user buffersReinette Chatre2006-10-112-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | lib/bitmap.c:bitmap_parse() is a library function that received as input a user buffer. This seemed to have originated from the way the write_proc function of the /proc filesystem operates. This has been reworked to not use kmalloc and eliminates a lot of get_user() overhead by performing one access_ok before using __get_user(). We need to test if we are in kernel or user space (is_user) and access the buffer differently. We cannot use __get_user() to access kernel addresses in all cases, for example in architectures with separate address space for kernel and user. This function will be useful for other uses as well; for example, taking input for /sysfs instead of /proc, so it was changed to accept kernel buffers. We have this use for the Linux UWB project, as part as the upcoming bandwidth allocator code. Only a few routines used this function and they were changed too. Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com> Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Cc: Paul Jackson <pj@sgi.com> Cc: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: likely profilingNick Piggin2006-10-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This likely profiling is pretty fun. I found a few possible problems in sched.c. This patch may be not measurable, but when I did measure long ago, nooping (un)likely cost a couple of % on scheduler heavy benchmarks, so it all adds up. Tweak some branch hints: - the 2nd 64 bits in the bitmask is likely to be populated, because it contains the first 28 bits (nearly 3/4) of the normal priorities. (ratio of 669669:691 ~= 1000:1). - it isn't unlikely that context switching switches to another process. it might be very rapidly switching to and from the idle process (ratio of 475815:419004 and 471330:423544). Let the branch predictor decide. - preempt_enable seems to be very often called in a nested preempt_disable or with interrupts disabled (ratio of 3567760:87965 ~= 40:1) Signed-off-by: Nick Piggin <npiggin@suse.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Daniel Walker <dwalker@mvista.com> Cc: Hua Zhong <hzhong@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix Module taint flags listing in Oops/panicFlorin Malita2006-10-111-45/+49
| | | | | | | | | | | | | | | | | | | | | | | | Module taint flags listing in Oops/panic has a couple of issues: * taint_flags() doesn't null-terminate the buffer after printing the flags * per-module taints are only set if the kernel is not already tainted (with that particular flag) => only the first offending module gets its taint info correctly updated Some additional changes: * 'license_gplok' is no longer needed - equivalent to !(taints & TAINT_PROPRIETARY_MODULE) - so we can drop it from struct module * exporting module taint info via /proc/module: pwc 88576 0 - Live 0xf8c32000 evilmod 6784 1 pwc, Live 0xf8bbf000 (PF) Signed-off-by: Florin Malita <fmalita@gmail.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] mm: kevent threads: use MPOL_DEFAULTChristoph Lameter2006-10-111-0/+7
| | | | | | | | | | | | | | | | Switch the memory policy of the kevent threads to MPOL_DEFAULT while leaving the kzalloc of the workqueue structure on interleave. This means that all code executed in the context of the kevent thread is allocating node local. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Alok Kataria <alok.kataria@calsoftinc.com> Cc: Andi Kleen <ak@suse.de> Cc: <pj@sgi.com> Cc: <shai@scalex86.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] swsusp: Use suspend_consoleRafael J. Wysocki2006-10-112-1/+15
| | | | | | | | | | Add suspend_console() and resume_console() to the suspend-to-disk code paths so that the users of netconsole can use swsusp with it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpuset ANSI prototypeAl Viro2006-10-101-1/+1
| | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Paul Jackson <pj@sgi.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] make kernel/relay.c __user-cleanAl Viro2006-10-101-19/+22
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] __user annotations: futexAl Viro2006-10-102-13/+14
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] swsusp: Make userland suspend work on SMP againRafael J. Wysocki2006-10-071-1/+1
| | | | | | | | | | Unfortunately one of the recent changes in swsusp has broken the userland suspend on SMP. Fix it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ixp4xxdefconfig arm fixesFrederik Deweerdt2006-10-061-1/+1
| | | | | | | | With the following patch, the ixp4xxdefconfig builds correctly. I'll test some more configs if I get some time. Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kauditd_thread warning fixAndrew Morton2006-10-061-1/+2
| | | | | | | | | | | | | | | | | | Squash this warning: kernel/audit.c: In function 'kauditd_thread': kernel/audit.c:367: warning: no return statement in function returning non-void We might as test kthread_should_stop(), although it's not very pointful at present. The code which starts this thread looks racy - the kernel could start multiple threads. Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-055-40/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
* IRQ: Typedef the IRQ handler function typeDavid Howells2006-10-051-3/+1
| | | | | | | Typedef the IRQ handler function type. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1356d1e5fd256997e3d3dce0777ab787d0515c7a commit)
* IRQ: Typedef the IRQ flow handler function typeDavid Howells2006-10-051-9/+3
| | | | | | | Typedef the IRQ flow handler function type. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 8e973fbdf5716b93a0a8c0365be33a31ca0fa351 commit)
* Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/confighLinus Torvalds2006-10-042-2/+0
|\ | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/davej/configh: Remove all inclusions of <linux/config.h> Manually resolved trivial path conflicts due to removed files in the sound/oss/ subdirectory.
| * Remove all inclusions of <linux/config.h>Dave Jones2006-10-042-2/+0
| | | | | | | | | | | | kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
* | Merge branch 'audit.b32' of ↵Linus Torvalds2006-10-042-5/+32
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current * 'audit.b32' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: [PATCH] message types updated [PATCH] name_count array overrun [PATCH] PPID filtering fix [PATCH] arch filter lists with < or > should not be accepted
| * | [PATCH] name_count array overrunSteve Grubb2006-10-041-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hi, This patch removes the rdev logging from the previous patch The below patch closes an unbounded use of name_count. This can lead to oopses in some new file systems. Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] PPID filtering fixAlexander Viro2006-10-041-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Thu, Sep 28, 2006 at 04:03:06PM -0400, Eric Paris wrote: > After some looking I did not see a way to get into audit_log_exit > without having set the ppid. So I am dropping the set from there and > only doing it at the beginning. > > Please comment/ack/nak as soon as possible. Ehh... That's one hell of an overhead to be had ;-/ Let's be lazy. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | [PATCH] arch filter lists with < or > should not be acceptedEric Paris2006-10-041-1/+8
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the kernel audit system represents arch's as numbers and will gladly accept comparisons between archs using >, <, >=, <= when the only thing that makes sense is = or !=. I'm told that the next revision of auditctl will do this checking but this will provide enforcement in the kernel even for old userspace. A simple command to show the issue would be to run auditctl -d entry,always -F arch>i686 -S chmod with this patch the kernel will reject this with -EINVAL Please comment/ack/nak as soon as possible. -Eric kernel/auditfilter.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | [PATCH] rcu: simplify/improve batch tuningOleg Nesterov2006-10-041-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kill a hard-to-calculate 'rsinterval' boot parameter and per-cpu rcu_data.last_rs_qlen. Instead, it adds adds a flag rcu_ctrlblk.signaled, which records the fact that one of CPUs has sent a resched IPI since the last rcu_start_batch(). Roughly speaking, we need two rcu_start_batch()s in order to move callbacks from ->nxtlist to ->donelist. This means that when ->qlen exceeds qhimark and continues to grow, we should send a resched IPI, and then do it again after we gone through a quiescent state. On the other hand, if it was already sent, we don't need to do it again when another CPU detects overflow of the queue. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add sched torture type to rcutortureJosh Triplett2006-10-041-1/+39
| | | | | | | | | | | | | | | | | | | | Implement torture testing for the "sched" variant of RCU, which uses preempt_disable, preempt_enable, and synchronize_sched. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add rcu_bh_sync torture type to rcutortureJosh Triplett2006-10-041-1/+15
| | | | | | | | | | | | | | | | | | | | | | Use the newly-generic synchronous deferred free function to implement torture testing for rcu_bh using synchronize_rcu_bh rather than the asynchronous call_rcu_bh. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: add rcu_sync torture type to rcutortureJosh Triplett2006-10-041-2/+15
| | | | | | | | | | | | | | | | | | | | Use the newly-generic synchronous deferred free function to implement torture testing for RCU using synchronize_rcu rather than the asynchronous call_rcu. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: refactor srcu_torture_deferred_free to work for any implementationJosh Triplett2006-10-041-24/+29
| | | | | | | | | | | | | | | | | | | | | | Make srcu_torture_deferred_free use cur_ops->sync() so it will work for any implementation. Move and rename it in preparation for use in the ops of other implementations. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] RCU: add fake writers to rcutortureJosh Triplett2006-10-041-5/+104
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcutorture currently has one writer and an arbitrary number of readers. To better exercise some of the code paths in RCU implementations, add fake writer threads which call the synchronize function for the RCU variant in a loop, with a delay between calls to arrange for different numbers of writers running in parallel. [bunk@stusta.de: cleanup] Acked-by: Paul McKenney <paulmck@us.ibm.com> Cc: Dipkanar Sarma <dipankar@in.ibm.com> Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Fix sign bug making rcu_random always return the same sequenceJosh Triplett2006-10-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcu_random uses a counter rrs_count to occasionally mix data from get_random_bytes into the state of its pseudorandom generator. However, the rrs_counter gets declared as an unsigned long, and rcu_random checks for --rrs_count < 0, so this code will never mix any real random data into the state, and will thus always return the same sequence of random numbers. Also, change the return value of rcu_random from long to unsigned long, to avoid potential issues caused by the use of the % operator, which can return negative values for negative left operands. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Avoid kthread_stop on invalid pointer if rcutorture reader ↵Josh Triplett2006-10-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | startup fails rcu_torture_init kmallocs the array of reader threads, then creates each one with kthread_run, cleaning up with rcu_torture_cleanup if this fails. rcu_torture_cleanup calls kthread_stop on any non-NULL pointer in the array; however, any readers after the one that failed to start up will have invalid pointers, not null pointers. Avoid this by using kzalloc instead. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Mention rcu_bh in description of rcutorture's torture_type ↵Josh Triplett2006-10-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | parameter The comment for rcutorture's torture_type parameter only lists the RCU variants rcu and srcu, but not rcu_bh; add rcu_bh to the list. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] rcu: Add MODULE_AUTHOR to rcutorture moduleJosh Triplett2006-10-041-0/+1
| | | | | | | | | | | | | | Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] SRCU: report out-of-memory errorsAlan Stern2006-10-042-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the init_srcu_struct() routine has no way to report out-of-memory errors. This patch (as761) makes it return -ENOMEM when the per-cpu data allocation fails. The patch also makes srcu_init_notifier_head() report a BUG if a notifier head can't be initialized. Perhaps it should return -ENOMEM instead, but in the most likely cases where this might occur I don't think any recovery is possible. Notifier chains generally are not created dynamically. [akpm@osdl.org: avoid statement-with-side-effect in macro] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] Add SRCU-based notifier chainsAlan Stern2006-10-041-1/+123
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch (as751) adds a new type of notifier chain, based on the SRCU (Sleepable Read-Copy Update) primitives recently added to the kernel. An SRCU notifier chain is much like a blocking notifier chain, in that it must be called in process context and its callout routines are allowed to sleep. The difference is that the chain's links are protected by the SRCU mechanism rather than by an rw-semaphore, so calling the chain has extremely low overhead: no memory barriers and no cache-line bouncing. On the other hand, unregistering from the chain is expensive and the chain head requires special runtime initialization (plus cleanup if it is to be deallocated). SRCU notifiers are appropriate for notifiers that will be called very frequently and for which unregistration occurs very seldom. The proposed "task notifier" scheme qualifies, as may some of the network notifiers. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] srcu-3: add SRCU operations to rcutorturePaul E. McKenney2006-10-041-10/+123
| | | | | | | | | | | | | | | | | | | | | | | | Adds SRCU operations to rcutorture and updates rcutorture documentation. Also increases the stress imposed by the rcutorture test. [bunk@stusta.de: make needlessly global code static] Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Cc: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] srcu-3: RCU variant permitting read-side blockingPaul E. McKenney2006-10-042-1/+258
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Updated patch adding a variant of RCU that permits sleeping in read-side critical sections. SRCU is as follows: o Each use of SRCU creates its own srcu_struct, and each srcu_struct has its own set of grace periods. This is critical, as it prevents one subsystem with a blocking reader from holding up SRCU grace periods for other subsystems. o The SRCU primitives (srcu_read_lock(), srcu_read_unlock(), and synchronize_srcu()) all take a pointer to a srcu_struct. o The SRCU primitives must be called from process context. o srcu_read_lock() returns an int that must be passed to the matching srcu_read_unlock(). Realtime RCU avoids the need for this by storing the state in the task struct, but SRCU needs to allow a given code path to pass through multiple SRCU domains -- storing state in the task struct would therefore require either arbitrary space in the task struct or arbitrary limits on SRCU nesting. So I kicked the state-storage problem up to the caller. Of course, it is not permitted to call synchronize_srcu() while in an SRCU read-side critical section. o There is no call_srcu(). It would not be hard to implement one, but it seems like too easy a way to OOM the system. (Hey, we have enough trouble with call_rcu(), which does -not- permit readers to sleep!!!) So, if you want it, please tell me why... [josht@us.ibm.com: sparse notation] Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Josh Triplett <josh@freedesktop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] msi: simplify msi sanity checks by adding with generic irq codeEric W. Biederman2006-10-041-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently msi.c is doing sanity checks that make certain before an irq is destroyed it has no more users. By adding irq_has_action I can perform the test is a generic way, instead of relying on a msi specific data structure. By performing the core check in dynamic_irq_cleanup I ensure every user of dynamic irqs has a test present and we don't free resources that are in use. In msi.c this allows me to kill the attrib.state member of msi_desc and all of the assciated code to maintain it. To keep from freeing data structures when irq cleanup code is called to soon changing dyanamic_irq_cleanup is insufficient because there are msi specific data structures that are also not safe to free. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Tony Luck <tony.luck@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] genirq: irq: add a dynamic irq creation APIEric W. Biederman2006-10-041-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] genirq: irq: add moved_masked_irqEric W. Biederman2006-10-041-7/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently move_native_irq disables and renables the irq we are migrating to ensure we don't take that irq when we are actually doing the migration operation. Disabling the irq needs to happen but sometimes doing the work is move_native_irq is too late. On x86 with ioapics the irq move sequences needs to be: edge_triggered: mask irq. move irq. unmask irq. ack irq. level_triggered: mask irq. ack irq. move irq. unmask irq. We can easily perform the edge triggered sequence, with the current defintion of move_native_irq. However the level triggered case does not map well. For that I have added move_masked_irq, to allow me to disable the irqs around both the ack and the move. Q: Why have we not seen this problem earlier? A: The only symptom I have been able to reproduce is that if we change the vector before acknowleding an irq the wrong irq is acknowledged. Since we currently are not reprogramming the irq vector during migration no problems show up. We have to mask the irq before we acknowledge the irq or else we could hit a window where an irq is asserted just before we acknowledge it. Edge triggered irqs do not have this problem because acknowledgements do not propogate in the same way. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] genirq: irq: convert the move_irq flag from a 32bit word to a single bitEric W. Biederman2006-10-041-3/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The primary aim of this patchset is to remove maintenances problems caused by the irq infrastructure. The two big issues I address are an artificially small cap on the number of irqs, and that MSI assumes vector == irq. My primary focus is on x86_64 but I have touched other architectures where necessary to keep them from breaking. - To increase the number of irqs I modify the code to look at the (cpu, vector) pair instead of just looking at the vector. With a large number of irqs available systems with a large irq count no longer need to compress their irq numbers to fit. Removing a lot of brittle special cases. For acpi guys the result is that irq == gsi. - Addressing the fact that MSI assumes irq == vector takes a few more patches. But suffice it to say when I am done none of the generic irq code even knows what a vector is. In quick testing on a large Unisys x86_64 machine we stumbled over at least one driver that assumed that NR_IRQS could always fit into an 8 bit number. This driver is clearly buggy today. But this has become a class of bugs that it is now much easier to hit. This patch: This is a minor space optimization. In practice I don't think this has any affect because of our alignment constraints and the other fields but there is not point in chewing up an uncessary word and since we already read the flag field this should improve the cache hit ratio of the irq handler. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* rcutorture: Fix incorrect description of default for nreaders parameterJosh Triplett2006-10-031-1/+1
| | | | | | | | | The comment for the nreaders parameter of rcutorture gives the default as 4*ncpus, but the value actually defaults to 2*ncpus; fix the comment. Signed-off-by: Josh Triplett <josh@freedesktop.org> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* remove duplicate "until" from kernel/workqueue.cRolf Eike Beer2006-10-031-1/+1
| | | | | | | s/until until/until/ Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* fix file specification in commentsUwe Zeisberger2006-10-031-1/+1
| | | | | | | Many files include the filename at the beginning, serveral used a wrong one. Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] scheduler: NUMA aware placement of sched_group_allnodesChristoph Lameter2006-10-031-3/+4
| | | | | | | | | | | | When the per cpu sched domains are build then they also need to be placed on the node where the cpu resides otherwise we will have frequent off node accesses which will slow down the system. Signed-off-by: Christoph Lameter <clameter@sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: fixing wrong comment for find_idlest_cpu()Satoru Takeuchi2006-10-031-1/+1
| | | | | | | | | Fixing wrong comment for find_idlest_cpu(). Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: cleanup sched_group cpu_power setupSiddha, Suresh B2006-10-031-63/+82
| | | | | | | | | | | | | | | | | | | | | Up to now sched group's cpu_power for each sched domain is initialized independently. This made the setup code ugly as the new sched domains are getting added. Make the sched group cpu_power setup code generic, by using domain child field and new domain flag in sched_domain. For most of the sched domains(except NUMA), sched group's cpu_power is now computed generically using the domain properties of itself and of the child domain. sched groups in NUMA domains are setup little differently and hence they don't use this generic mechanism. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: introduce child field in sched_domainSiddha, Suresh B2006-10-031-10/+30
| | | | | | | | | | | | | | | Introduce the child field in sched_domain struct and use it in sched_balance_self(). We will also use this field in cleaning up the sched group cpu_power setup(done in a different patch) code. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: don't print migration cost when only 1 CPUDave Jones2006-10-031-6/+8
| | | | | | | | | | If only a single CPU is present, printing this doesn't make much sense. Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: remove unnecessary sched group allocationsSiddha, Suresh B2006-10-031-66/+38
| | | | | | | | | | | | | Remove dynamic sched group allocations for MC and SMP domains. These allocations can easily fail on big systems(1024 or so CPUs) and we can live with out these dynamic allocations. [akpm@osdl.org: build fix] Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: force /sbin/init off isolated cpusNick Piggin2006-10-031-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | Force /sbin/init off isolated cpus (unless every CPU is specified as an isolcpu). Users seem to think that the isolated CPUs shouldn't have much running on them to begin with. That's fair enough: intuitive, I guess. It also means that the cpu affinity masks of tasks will not include isolcpus by default, which is also more intuitive, perhaps. /sbin/init is spawned from the boot CPU's idle thread, and /sbin/init starts the rest of userspace. So if the boot CPU is specified to be an isolcpu, then prior to this patch, all of userspace will be run there. (throw in a couple of plausible devinit -> cpuinit conversions I spotted while we're here). Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Dimitri Sivanich <sivanich@sgi.com> Acked-by: Paul Jackson <pj@sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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