- 15 Jul, 2006 40 commits
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Shailabh Nagar authored
In send_cpu_listeners(), which is called on the exit path, a down_write() was protecting operations like skb_clone() and genlmsg_unicast() that do GFP_KERNEL allocations. If the oom-killer decides to kill tasks to satisfy the allocations,the exit of those tasks could block on the same semphore. The down_write() was only needed to allow removal of invalid listeners from the listener list. The patch converts the down_write to a down_read and defers the removal to a separate critical region. This ensures that even if the oom-killer is called, no other task's exit is blocked as it can still acquire another down_read. Thanks to Andrew Morton & Herbert Xu for pointing out the oom related pitfalls, and to Chandra Seetharaman for suggesting this fix instead of using something more complex like RCU. Signed-off-by:
Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by:
Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by:
Andrew Morton <akpm@osdl.org> Signed-off-by:
Linus Torvalds <torvalds@osdl.org>
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Shailabh Nagar authored
On systems with a large number of cpus, with even a modest rate of tasks exiting per cpu, the volume of taskstats data sent on thread exit can overflow a userspace listener's buffers. One approach to avoiding overflow is to allow listeners to get data for a limited and specific set of cpus. By scaling the number of listeners and/or the cpus they monitor, userspace can handle the statistical data overload more gracefully. In this patch, each listener registers to listen to a specific set of cpus by specifying a cpumask. The interest is recorded per-cpu. When a task exits on a cpu, its taskstats data is unicast to each listener interested in that cpu. Thanks to Andrew Morton for pointing out the various scalability and general concerns of previous attempts and for suggesting this design. [akpm@osdl.org: build fix] Signed-off-by:
Balbir Singh <balbir@in.ibm.com> Signed-off-by:
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Shailabh Nagar authored
Don't send taskstats (per-pid or per-tgid) on thread exit when no one is listening for such data. Currently the taskstats interface allocates a structure, fills it in and calls netlink to send out per-pid and per-tgid stats regardless of whether a userspace listener for the data exists (netlink layer would check for that and avoid the multicast). As a result of this patch, the check for the no-listener case is performed early, avoiding the redundant allocation and filling up of the taskstats structures. Signed-off-by:
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Shailabh Nagar authored
Change documentation and example program to reflect the flow control issues being addressed by the cpumask changes. Signed-off-by:
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Shailabh Nagar authored
Send per-tgid data only once during exit of a thread group instead of once with each member thread exit. Currently, when a thread exits, besides its per-tid data, the per-tgid data of its thread group is also sent out, if its thread group is non-empty. The per-tgid data sent consists of the sum of per-tid stats for all *remaining* threads of the thread group. This patch modifies this sending in two ways: - the per-tgid data is sent only when the last thread of a thread group exits. This cuts down heavily on the overhead of sending/receiving per-tgid data, especially when other exploiters of the taskstats interface aren't interested in per-tgid stats - the semantics of the per-tgid data sent are changed. Instead of being the sum of per-tid data for remaining threads, the value now sent is the true total accumalated statistics for all threads that are/were part of the thread group. The patch also addresses a minor issue where failure of one accounting subsystem to fill in the taskstats structure was causing the send of taskstats to not be sent at all. The patch has been tested for stability and run cerberus for over 4 hours on an SMP. [akpm@osdl.org: bugfixes] Signed-off-by:
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Shailabh Nagar authored
Export I/O delays seen by a task through /proc/<tgid>/stats for use in top etc. Note that delays for I/O done for swapping in pages (swapin I/O) is clubbed together with all other I/O here (this is not the case in the netlink interface where the swapin I/O is kept distinct) [akpm@osdl.org: printk warning fix] Signed-off-by:
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Shailabh Nagar authored
Some documentation for delay accounting. Signed-off-by:
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Shailabh Nagar authored
Usage of taskstats interface by delay accounting. Signed-off-by:
Shailabh Nagar <nagar@us.ibm.com> Signed-off-by:
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Shailabh Nagar authored
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:
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Balbir Singh authored
Two utilities for simplifying usage of NETLINK_GENERIC interface. Signed-off-by:
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Chandra Seetharaman authored
Make the task-related schedstats functions callable by delay accounting even if schedstats collection isn't turned on. This removes the dependency of delay accounting on schedstats. Signed-off-by:
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Shailabh Nagar authored
Unlike earlier iterations of the delay accounting patches, now delays are only collected for the actual I/O waits rather than try and cover the delays seen in I/O submission paths. Account separately for block I/O delays incurred as a result of swapin page faults whose frequency can be affected by the task/process' rss limit. Hence swapin delays can act as feedback for rss limit changes independent of I/O priority changes. Signed-off-by:
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Shailabh Nagar authored
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:
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Shailabh Nagar authored
Add another list utility function to check for last element in a list. Signed-off-by:
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Mike Rapoport authored
Add frame buffer driver for the 2700G LCD controller present on CompuLab CM-X270 computer module. [adaplas] - Add more informative help text to Kconfig - Make DEBUG a Kconfig option as FB_MBX_DEBUG - Remove #include mbxdebug.c, this is frowned upon - Remove redundant casts - Arrange #include's alphabetically - Trivial whitespace Signed-off-by:
Mike Rapoport <mike@compulab.co.il> Signed-off-by:
Antonino Daplas <adaplas@pol.net> Signed-off-by:
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Eric Paris authored
After some discussion on the actual meaning of the filesystem class security check in try context mount it was determined that the checks for the context= mount options were not correct if fscontext mount option had already been used. When labeling the superblock we should be checking relabel_from and relabel_to. But if the superblock has already been labeled (with fscontext) then context= is actually labeling the inodes, and so we should be checking relabel_from and associate. This patch fixes which checks are called depending on the mount options. Signed-off-by:
Eric Paris <eparis@redhat.com> Acked-by:
Stephen Smalley <sds@tycho.nsa.gov> Acked-by:
James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by:
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Adrian Bunk authored
The lockdep options should depend on DEBUG_KERNEL since: - they are kernel debugging options and - they do otherwise break the DEBUG_KERNEL menu structure Signed-off-by:
Adrian Bunk <bunk@stusta.de> Acked-by:
Ingo Molnar <mingo@elte.hu> Signed-off-by:
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Kylene Jo Hall authored
Fix the start and len variables that should be using the new resource_size_t. Signed_off_by: Kylene Hall <kjhall@us.ibm.com> Signed-off-by:
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Kylene Jo Hall authored
Some machine manufacturers are not sticking to the TCG specifications and including an ACPI DSDT entry for the TPM which allows PNP discovery of the device. Signed-off-by:
Kylene Hall <kjhall@us.ibm.com> Signed-off-by:
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Kylene Jo Hall authored
Under stress testing I found that the interrupt is not always cleared. Signed-off-by:
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Al Viro authored
It's way past time to bump it to 8. Everyone had been warned - for months now. RH kernels have had this for more than a year. Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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Randy Dunlap authored
Add actual mailing list email addresses for the 4 that were only listing a web page. Signed-off-by:
Randy Dunlap <rdunlap@xenotime.net> Signed-off-by:
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Randy Dunlap authored
kfree(devname) on the misc_register() failure path. Otherwise it is lost forever. Signed-off-by:
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Ingo Molnar authored
On platforms that have __ARCH_WANT_UNLOCKED_CTXSW set and want to implement lock validator support there's a bug in rq->lock handling: in this case we dont 'carry over' the runqueue lock into another task - but still we did a spinlock_release() of it. Fix this by making the spinlock_release() in context_switch() dependent on !__ARCH_WANT_UNLOCKED_CTXSW. (Reported by Ralf Baechle on MIPS, which has __ARCH_WANT_UNLOCKED_CTXSW. This fixes a lockdep-internal BUG message on such platforms.) Signed-off-by:
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Jim Cromie authored
- rename EXPORTed gpio vtables from {scx200,pc8736x}_access to _gpio_ops new name is much closer to the vtable-name struct nsc_gpio_ops, should be clearer. Also rename the _fops vtable var to _fileops to better disambiguate it from the gpio vtable. Signed-off-by:Jim Cromie <jim.cromie@gmail.com> Signed-off-by:
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Jim Cromie authored
- pure cosmetics: lose needless newlines. - rename EXPORTed gpio vtables from {scx200,pc8736x}_access to _gpio_ops new name is much closer to the vtable-name struct nsc_gpio_ops, should be clearer. Also rename the _fops vtable var to _fileops to better disambiguate it from the gpio vtable. Signed-off-by: -
Jim Cromie authored
drops gpio_set_high, gpio_set_low from the nsc_gpio_ops vtable. While we can't drop them from scx200_gpio (or can we?), we dont need them for new users of the exported vtable; gpio_set(1), gpio_set(0) work fine. Signed-off-by:
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Rolf Eike Beer authored
pci_dac_set_dma_mask() gives only a single match in the whole kernel tree and that's in this doc file. The best candidate for replacement is pci_dac_dma_supported(). Signed-off-by:
Rolf Eike Beer <eike-kernel@sf-tec.de> Cc: Greg KH <greg@kroah.com> Acked-by:
"David S. Miller" <davem@davemloft.net> Signed-off-by:
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Rolf Eike Beer authored
Documentation for register_chrdev() was missing completely. [akpm@osdl.org: kerneldocification] Signed-off-by:
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Roland Dreier authored
Currently, the code in lib/idr.c uses a bare spin_lock(&idp->lock) to do internal locking. This is a nasty trap for code that might call idr functions from different contexts; for example, it seems perfectly reasonable to call idr_get_new() from process context and idr_remove() from interrupt context -- but with the current locking this would lead to a potential deadlock. The simplest fix for this is to just convert the idr locking to use spin_lock_irqsave(). In particular, this fixes a very complicated locking issue detected by lockdep, involving the ib_ipoib driver's priv->lock and dev->_xmit_lock, which get involved with the ib_sa module's query_idr.lock. Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Zach Brown <zach.brown@oracle.com>, Signed-off-by:
Roland Dreier <rolandd@cisco.com> Signed-off-by:
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Jeff Mahoney authored
On systems with block devices containing a slash (virtual dasd, cciss, etc), reiserfs will fail to initialize /proc/fs/reiserfs/<dev> due to it being interpreted as a subdirectory. The generic block device code changes the / to ! for use in the sysfs tree. This patch uses that convention. Tested by making dm devices use dm/<number> rather than dm-<number> [akpm@osdl.org: name variables consistently] Signed-off-by:
Jeff Mahoney <jeffm@suse.com> Signed-off-by:
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Chris Boot authored
Add the DRVNAME define to remove the two separate references of the driver name by string, and move the .driver.owner into the existing .driver sub-structure. Signed-off-by:
Chris Boot <bootc@bootc.net> Signed-off-by:
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OGAWA Hirofumi authored
IRQs must be disabled before taking ->siglock. Noticed by lockdep. Signed-off-by:
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by:
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john stultz authored
Resolve problems seen w/ APM suspend. Due to resume initialization ordering, its possible we could get a timer interrupt before the timekeeping resume() function is called. This patch ensures we don't do any timekeeping accounting before we're fully resumed. (akpm: fixes the machine-freezes-on-APM-resume bug) Signed-off-by:
John Stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by:
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Jim Cromie authored
Remove the scx200_gpio's cdev-array & ksalloc, replacing it with a single static struct cdev, which is sufficient for all the pins. cdev_put is commented out since kernel wont link properly with it, and its apparently not needed. With these patches, this driver continues to work with Chris Boot's leds_48xx driver. Signed-off-by Jim Cromie <jim.cromie@gmail.com> Signed-off-by:
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Jim Cromie authored
this patch is mostly cleanup of scx200_gpio : - drop #include <linux/config.h> - s/DEVNAME/DRVNAME/ apparently a convention - replace variable num_pins with #define MAX_PINS - s/dev/devid/ to clarify that its a dev_t, not a struct device dev. - move devid = MKDEV(major,0) into branch where its needed. 2 minor 'changes' : - reduced MAX_PINS from 64 to 32. Ive never tested other pins, and theyre all multiplexed with other functions, some of which may be in use on my soekris 4801, so I dont know what testing should yield. - +EXPORT_SYMBOL(scx200_access); This exposes the driver's vtable, which another driver can use along with #include <linux/nsc_gpio.h>, to manipulate a gpio-pin. Signed-off-by Jim Cromie <jim.cromie@gmail.com> Signed-off-by:
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Adrian Bunk authored
Christoph Hellwig: open_softirq just enables a softirq. The softirq array is statically allocated so to add a new one you would have to patch the kernel. So there's no point to keep this export at all as any user would have to patch the enum in include/linux/interrupt.h anyway. Signed-off-by:
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Adrian Bunk authored
Signed-off-by:
Mike Miller <mike.miller@hp.com> Signed-off-by:
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Luca Tettamanti authored
When CONFIG_RT_MUTEX_TESTER is enabled kernel refuses to suspend the machine because it's unable to freeze the rt-test-* threads. Add try_to_freeze() after schedule() so that the threads will be freezed correctly; I've tested the patch and it lets the notebook suspends and resumes nicely. Signed-off-by:
Luca Tettamanti <kronos.it@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Arjan van de Ven authored
The delete partition IOCTL takes the bd_mutex for both the disk and the partition; these have an obvious hierarchical relationship and this patch annotates this relationship for lockdep. Signed-off-by:
Arjan van de Ven <arjan@linux.intel.com> Acked-by:
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