- 30 Nov, 2012 4 commits
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Mark Asselstine authored
The turbostat Makefile is pretty simple, its output is placed in the same directory as the source, the install rule has no concept of a prefix or sysroot, and you can set CC to use a specific compiler but not use the more familiar CROSS_COMPILE. By making a few minor changes these limitations are removed while leaving the default behavior matching what it used to be. Example build with these changes: make CROSS_COMPILE=i686-wrs-linux-gnu- DESTDIR=/tmp install or from the tools directory make CROSS_COMPILE=i686-wrs-linux-gnu- DESTDIR=/tmp turbostat_install Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com> Signed-off-by: Len Brown <len.brown@intel.com>
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Colin Ian King authored
Instead of returning out of for_every_cpu() we should break out of the loop= which will then tidy up correctly by closing the file /proc/stat. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Len Brown <len.brown@intel.com>
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Len Brown authored
Show power in Watts and temperature in Celsius when hardware support is present. Intel's Sandy Bridge and Ivy Bridge processor generations support RAPL (Run-Time-Average-Power-Limiting). Per the Intel SDM (Intel
® 64 and IA-32 Architectures Software Developer Manual) RAPL provides hardware energy counters and power control MSRs (Model Specific Registers). RAPL MSRs are designed primarily as a method to implement power capping. However, they are useful for monitoring system power whether or not power capping is used. In addition, Turbostat now shows temperature from DTS (Digital Thermal Sensor) and PTM (Package Thermal Monitor) hardware, if present. As before, turbostat reads MSRs, and never writes MSRs. New columns are present in turbostat output: The Pkg_W column shows Watts for each package (socket) in the system. On multi-socket systems, the system summary on the 1st row shows the sum for all sockets together. The Cor_W column shows Watts due to processors cores. Note that Core_W is included in Pkg_W. The optional GFX_W column shows Watts due to the graphics "un-core". Note that GFX_W is included in Pkg_W. The optional RAM_W column on server processors shows Watts due to DRAM DIMMS. As DRAM DIMMs are outside the processor package, RAM_W is not included in Pkg_W. The optional PKG_% and RAM_% columns on server processors shows the % of time in the measurement interval that RAPL power limiting is in effect on the package and on DRAM. Note that the RAPL energy counters have some limitations. First, hardware updates the counters about once every milli-second. This is fine for typical turbostat measurement intervals > 1 sec. However, when turbostat is used to measure events that approach 1ms, the counters are less useful. Second, the 32-bit energy counters are subject to wrapping. For example, a counter incrementing 15 micro-Joule units on a 130 Watt TDP server processor could (in theory) roll over in about 9 minutes. Turbostat detects and handles up to 1 counter overflow per measurement interval. But when the measurement interval exceeds the guaranteed counter range, we can't detect if more than 1 overflow occured. So in this case turbostat indicates that the results are in question by replacing the fractional part of the Watts in the output with "**": Pkg_W Cor_W GFX_W 3** 0** 0** Third, the RAPL counters are energy (Joule) counters -- they sum up weighted events in the package to estimate energy consumed. They are not analong power (Watt) meters. In practice, they tend to under-count because they don't cover every possible use of energy in the package. The accuracy of the RAPL counters will vary between product generations, and between SKU's in the same product generation, and with temperature. turbostat's -v (verbose) option now displays more power and thermal configuration information -- as shown on the turbostat.8 manual page. For example, it now displays the Package and DRAM Thermal Design Power (TDP): cpu0: MSR_PKG_POWER_INFO: 0x2f064001980410 (130 W TDP, RAPL 51 - 200 W, 0.045898 sec.) cpu0: MSR_DRAM_POWER_INFO,: 0x28025800780118 (35 W TDP, RAPL 15 - 75 W, 0.039062 sec.) cpu8: MSR_PKG_POWER_INFO: 0x2f064001980410 (130 W TDP, RAPL 51 - 200 W, 0.045898 sec.) cpu8: MSR_DRAM_POWER_INFO,: 0x28025800780118 (35 W TDP, RAPL 15 - 75 W, 0.039062 sec.) Signed-off-by: Len Brown <len.brown@intel.com> -
Len Brown authored
In periodic mode, turbostat writes to stdout, but users were un-able to re-direct stdout, eg. turbostat > outputfile would result in an empty outputfile. Signed-off-by: Len Brown <len.brown@intel.com>
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- 27 Nov, 2012 1 commit
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Len Brown authored
Turbostat assumed if it can't migrate to a CPU, then the CPU must have gone off-line and turbostat should re-initialize with the new topology. But if turbostat can not migrate because it is restricted by a cpuset, then it will fail to migrate even after re-initialization, resulting in an infinite loop. Spit out a warning when we can't migrate and endure only 2 re-initialize cycles in a row before giving up and exiting. Signed-off-by: Len Brown <len.brown@intel.com>
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- 24 Nov, 2012 2 commits
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Len Brown authored
The Run Time Average Power Limiting interface is currently model specific, present on Sandy Bridge and Ivy Bridge processors. These #defines correspond to documentation in the latest "Intel
® 64 and IA-32 Architectures Software Developer Manual", plus some typos in that document corrected. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org -
Len Brown authored
Now that turbostat is built in the kernel tree, it can share MSR #defines with the kernel. Signed-off-by: Len Brown <len.brown@intel.com> Cc: x86@kernel.org
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- 01 Nov, 2012 2 commits
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Len Brown authored
When invald MSR's are specified on the command line, turbostat should simply print an error and exit. Signed-off-by: Len Brown <len.brown@intel.com>
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Len Brown authored
Fix regression caused by commit 8e180f3c (tools/power turbostat: add [-d MSR#][-D MSR#] options to print counter deltas) Signed-off-by: Len Brown <len.brown@intel.com>
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- 30 Oct, 2012 17 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull GPIO fixes from Linus Walleij: - Fix a potential bit wrap issue in the Timberdale driver - Fix up the buffer allocation size in the 74x164 driver - Set the value in direction_output() right in the mvebu driver - Return proper error codes for invalid GPIOs - Fix an off-mode bug for the OMAP - Don't initialize the mask_cach on the mvebu driver * tag 'gpio-fixes-v3.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: GPIO: mvebu-gpio: Don't initialize the mask_cache gpio/omap: fix off-mode bug: clear debounce settings on free/reset gpiolib: Don't return -EPROBE_DEFER to sysfs, or for invalid gpios gpio: mvebu: correctly set the value in direction_output() gpio-74x164: Fix buffer allocation size gpio-timberdale: fix a potential wrapping issue
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git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4Linus Torvalds authored
Pull ext4 bugfix from Ted Ts'o: "This fixes the root cause of the ext4 data corruption bug which raised a ruckus on LWN, Phoronix, and Slashdot. This bug only showed up when non-standard mount options (journal_async_commit and/or journal_checksum) were enabled, and when the file system was not cleanly unmounted, but the root cause was the inode bitmap modifications was not being properly journaled. This could potentially lead to minor file system corruptions (pass 5 complaints with the inode allocation bitmap) after an unclean shutdown under the wrong/unlucky workloads, but it turned into major failure if the journal_checksum and/or jouaral_async_commit was enabled." * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix unjournaled inode bitmap modification
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block driver update from Jens Axboe: "Distilled down variant, the rest will pass over to 3.8. I pulled it into the for-linus branch I had waiting for a pull request as well, in case you are wondering why there are new entries in here too. This also got rid of two reverts and the ones of the mtip32xx patches that went in later in the 3.6 cycle, so the series looks a bit cleaner." * 'for-linus' of git://git.kernel.dk/linux-block: loop: Make explicit loop device destruction lazy mtip32xx:Added appropriate timeout value for secure erase xen/blkback: Change xen_vbd's flush_support and discard_secure to have type unsigned int, rather than bool cciss: select CONFIG_CHECK_SIGNATURE cciss: remove unneeded memset() xen/blkback: use kmem_cache_zalloc instead of kmem_cache_alloc/memset pktcdvd: update MAINTAINERS floppy: remove dr, reuse drive on do_floppy_init floppy: use common function to check if floppies can be registered floppy: properly handle failure on add_disk loop floppy: do put_disk on current dr if blk_init_queue fails floppy: don't call alloc_ordered_workqueue inside the alloc_disk loop xen/blkback: Fix compile warning block: Add blk_rq_pos(rq) to sort rq when plushing drivers/block: remove CONFIG_EXPERIMENTAL block: remove CONFIG_EXPERIMENTAL vfs: fix: don't increase bio_slab_max if krealloc() fails blkcg: stop iteration early if root_rl is the only request list blkcg: Fix use-after-free of q->root_blkg and q->root_rl.blkg
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Andrew Lunn authored
Due to the SMP nature of some of the chips, which have per CPU registers, the driver does not use the generic irq_gc_mask_set_bit() & irq_gc_mask_clr_bit() functions, which only support a single register. The driver has its own implementation of these functions, which can pick the correct register depending on the CPU being used. The functions do however use the gc->mask_cache value. The call to irq_setup_generic_chip() was passing IRQ_GC_INIT_MASK_CACHE, which caused the gc->mask_cache to be initialized to the contents of some random register. This resulted in unexpected interrupts been delivered from random GPIO lines. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Jamie Lentin <jm@lentin.co.uk> Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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Dave Chinner authored
xfstests has always had random failures of tests due to loop devices failing to be torn down and hence leaving filesytems that cannot be unmounted. This causes test runs to immediately stop. Over the past 6 or 7 years we've added hacks like explicit unmount -d commands for loop mounts, losetup -d after unmount -d fails, etc, but still the problems persist. Recently, the frequency of loop related failures increased again to the point that xfstests 259 will reliably fail with a stray loop device that was not torn down. That is despite the fact the test is above as simple as it gets - loop 5 or 6 times running mkfs.xfs with different paramters: lofile=$(losetup -f) losetup $lofile "$testfile" "$MKFS_XFS_PROG" -b size=512 $lofile >/dev/null || echo "mkfs failed!" sync losetup -d $lofile And losteup -d $lofile is failing with EBUSY on 1-3 of these loops every time the test is run. Turns out that blkid is running simultaneously with losetup -d, and so it sees an elevated reference count and returns EBUSY. But why is blkid running? It's obvious, isn't it? udev has decided to try and find out what is on the block device as a result of a creation notification. And it is racing with mkfs, so might still be scanning the device when mkfs finishes and we try to tear it down. So, make losetup -d force autoremove behaviour. That is, when the last reference goes away, tear down the device. xfstests wants it *gone*, not causing random teardown failures when we know that all the operations the tests have specifically run on the device have completed and are no longer referencing the loop device. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Selvan Mani authored
Added appropriate timeout value for secure erase based on identify device data Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com> Signed-off-by: Selvan Mani <smani@micron.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Oliver Chick authored
xen/blkback: Change xen_vbd's flush_support and discard_secure to have type unsigned int, rather than bool Changing the type of bdev parameters to be unsigned int :1, rather than bool. This is more consistent with the types of other features in the block drivers. Signed-off-by: Oliver Chick <oliver.chick@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Akinobu Mita authored
The patch cciss-use-check_signature.patch in -mm tree introduced a build error: drivers/built-in.o: In function `CISS_signature_present': drivers/block/cciss.c:4270: undefined reference to `check_signature' Add missing CONFIG_CHECK_SIGNATURE to fix this issue. Reported-by: Fengguang Wu <wfg@linux.intel.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Fengguang Wu <wfg@linux.intel.com> Cc: Mike Miller <mike.miller@hp.com> Cc: Jens Axboe <axboe@kernel.dk> Acked-by: "Stephen M. Cameron" <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Wei Yongjun authored
The memory return by kzalloc() or kmem_cache_zalloc() has already be set to zero, so remove useless memset(0). spatch with a semantic match is used to found this problem. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Mike Miller <mike.miller@hp.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Wei Yongjun authored
Using kmem_cache_zalloc() instead of kmem_cache_alloc() and memset(). spatch with a semantic match is used to found this problem. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Jiri Kosina authored
Peter is not going to maintain the driver any more. I have the hardware. Acked-by: Peter Osterlund <petero2@telia.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Herton Ronaldo Krzesinski authored
This is a small cleanup, that also may turn error handling of unitialized disks more readable. We don't need a separate variable to track allocated disks, remove dr and reuse drive variable instead. Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Herton Ronaldo Krzesinski authored
The same checks to see if a drive can be or is registered are repeated through the code, factor out the checks in a common function and replace the repeated checks with it. Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Herton Ronaldo Krzesinski authored
On floppy initialization, if something failed inside the loop we call add_disk, there was no cleanup of previous iterations in the error handling. Cc: stable@vger.kernel.org Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Herton Ronaldo Krzesinski authored
If blk_init_queue fails, we do not call put_disk on the current dr (dr is decremented first in the error handling loop). Cc: stable@vger.kernel.org Reviewed-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Herton Ronaldo Krzesinski authored
Since commit 070ad7e7 ("floppy: convert to delayed work and single-thread wq"), we end up calling alloc_ordered_workqueue multiple times inside the loop, which shouldn't be intended. Besides the leak, other side effect in the current code is if blk_init_queue fails, we would end up calling unregister_blkdev even if we didn't call yet register_blkdev. Just moved the allocation of floppy_wq before the loop, and adjusted the code accordingly. Cc: stable@vger.kernel.org # 3.5+ Acked-by: Vivek Goyal <vgoyal@redhat.com> Reviewed-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Konrad Rzeszutek Wilk authored
drivers/block/xen-blkback/xenbus.c:260:5: warning: symbol 'xenvbd_sysfs_addif' was not declared. Should it be static? drivers/block/xen-blkback/xenbus.c:284:6: warning: symbol 'xenvbd_sysfs_delif' was not declared. Should it be static? Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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- 29 Oct, 2012 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-clientLinus Torvalds authored
Pull Ceph fixes form Sage Weil: "There are two fixes in the messenger code, one that can trigger a NULL dereference, and one that error in refcounting (extra put). There is also a trivial fix that in the fs client code that is triggered by NFS reexport." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: ceph: fix dentry reference leak in encode_fh() libceph: avoid NULL kref_put when osd reset races with alloc_msg rbd: reset BACKOFF if unable to re-queue
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David Zafman authored
Call to d_find_alias() needs a corresponding dput() This fixes http://tracker.newdream.net/issues/3271Signed-off-by: David Zafman <david.zafman@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
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Eric Sandeen authored
commit 119c0d44 changed ext4_new_inode() such that the inode bitmap was being modified outside a transaction, which could lead to corruption, and was discovered when journal_checksum found a bad checksum in the journal during log replay. Nix ran into this when using the journal_async_commit mount option, which enables journal checksumming. The ensuing journal replay failures due to the bad checksums led to filesystem corruption reported as the now infamous "Apparent serious progressive ext4 data corruption bug" [ Changed by tytso to only call ext4_journal_get_write_access() only when we're fairly certain that we're going to allocate the inode. ] I've tested this by mounting with journal_checksum and running fsstress then dropping power; I've also tested by hacking DM to create snapshots w/o first quiescing, which allows me to test journal replay repeatedly w/o actually power-cycling the box. Without the patch I hit a journal checksum error every time. With this fix it survives many iterations. Reported-by: Nix <nix@esperi.org.uk> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 28 Oct, 2012 11 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/stagingLinus Torvalds authored
Pull i2c subsystem fixes from Jean Delvare. * 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c-i801: Fix comment i2c-i801: Simplify dependency towards GPIOLIB i2c-stub: Move to drivers/i2c
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Jean Delvare authored
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Jean Delvare authored
Arbitrarily selecting GPIOLIB causes trouble on some architectures, so don't do that. Instead, just make the optional multiplexing code depend on CONFIG_I2C_MUX_GPIO instead of CONFIG_I2C_MUX for now. We can revisit if the i2c-i801 driver ever supports other multiplexing flavors. Also make that optional code depend on DMI, as it won't do anything without that. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Fengguang Wu <fengguang.wu@intel.com>
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Jean Delvare authored
Move the i2c-stub driver to drivers/i2c, to match the Kconfig entry. This is less confusing that way. I also fixed all checkpatch warnings and errors. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Peter Huewe <peterhuewe@gmx.de>
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktestLinus Torvalds authored
Pull ktest confusion fix from Steven Rostedt: "With the v3.7-rc2 kernel, the network cards on my target boxes were not being brought up. I found that the modules for the network was not being installed. This was due to the config CONFIG_MODULES_USE_ELF_RELA that came before CONFIG_MODULES, and confused ktest in thinking that CONFIG_MODULES=y was not found. Ktest needs to test all configs and not just stop if something starts with CONFIG_MODULES." * tag 'ktest-v3.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest: ktest: Fix ktest confusion with CONFIG_MODULES_USE_ELF_RELA
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/miscLinus Torvalds authored
Pull minor spi MXS fixes from Mark Brown: "These fixes are both pretty minor ones and are driver local." * tag 'spi-mxs' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc: spi: mxs: Terminate DMA in case of DMA timeout spi: mxs: Assign message status after transfer finished
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds authored
Pull arm-soc fixes from Arnd Bergmann: "Bug fixes for a number of ARM platforms, mostly OMAP, imx and at91. These come a little later than I had hoped but unfortunately we had a few of these patches cause regressions themselves and had to work out how to deal with those in the meantime." * tag 'fixes-for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (38 commits) Revert "ARM i.MX25: Fix PWM per clock lookups" ARM: versatile: fix versatile_defconfig ARM: mvebu: update defconfig with 3.7 changes ARM: at91: fix at91x40 build ARM: socfpga: Fix socfpga compilation with early_printk() enabled ARM: SPEAr: Remove unused empty files MAINTAINERS: Add arm-soc tree entry ARM: dts: mxs: add the "clock-names" for gpmi-nand ARM: ux500: Correct SDI5 address and add some format changes ARM: ux500: Specify AMBA Primecell IDs for Nomadik I2C in DT ARM: ux500: Fix build error relating to IRQCHIP_SKIP_SET_WAKE ARM: at91: drop duplicated config SOC_AT91SAM9 entry ARM: at91/i2c: change id to let i2c-at91 work ARM: at91/i2c: change id to let i2c-gpio work ARM: at91/dts: at91sam9g20ek_common: Fix typos in buttons labels. ARM: at91: fix external interrupt specification in board code ARM: at91: fix external interrupts in non-DT case ARM: at91: at91sam9g10: fix SOC type detection ARM: at91/tc: fix typo in the DT document ARM: AM33XX: Fix configuration of dmtimer parent clock by dmtimer driverDate:Wed, 17 Oct 2012 13:55:55 -0500 ...
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Mikulas Patocka authored
Functions generic_file_splice_read and generic_file_splice_write access the pagecache directly. For block devices these functions must be locked so that block size is not changed while they are in progress. This patch is an additional fix for commit b87570f5 ("Fix a crash when block device is read and block size is changed at the same time") that locked aio_read, aio_write and mmap against block size change. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mikulas Patocka authored
Use rcu_read_lock_sched / rcu_read_unlock_sched / synchronize_sched instead of rcu_read_lock / rcu_read_unlock / synchronize_rcu. This is an optimization. The RCU-protected region is very small, so there will be no latency problems if we disable preempt in this region. So we use rcu_read_lock_sched / rcu_read_unlock_sched that translates to preempt_disable / preempt_disable. It is smaller (and supposedly faster) than preemptible rcu_read_lock / rcu_read_unlock. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mikulas Patocka authored
This patch introduces new barrier pair light_mb() and heavy_mb() for percpu rw semaphores. This patch fixes a bug in percpu-rw-semaphores where a barrier was missing in percpu_up_write. This patch improves performance on the read path of percpu-rw-semaphores: on non-x86 cpus, there was a smp_mb() in percpu_up_read. This patch changes it to a compiler barrier and removes the "#if defined(X86) ..." condition. From: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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