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2013-12-05padata: Fix wrong usage of rcu_dereference()Mathias Krause1-1/+1
A kernel with enabled lockdep complains about the wrong usage of rcu_dereference() under a rcu_read_lock_bh() protected region. =============================== [ INFO: suspicious RCU usage. ] 3.13.0-rc1+ #126 Not tainted ------------------------------- linux/kernel/padata.c:115 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 1 lock held by cryptomgr_test/153: #0: (rcu_read_lock_bh){.+....}, at: [<ffffffff8115c235>] padata_do_parallel+0x5/0x270 Fix that by using rcu_dereference_bh() instead. Signed-off-by: Mathias Krause <minipli@googlemail.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-10-30padata: make the sequence counter an atomic_tMathias Krause1-5/+4
Using a spinlock to atomically increase a counter sounds wrong -- we've atomic_t for this! Also move 'seq_nr' to a different cache line than 'lock' to reduce cache line trashing. This has the nice side effect of decreasing the size of struct parallel_data from 192 to 128 bytes for a x86-64 build, e.g. occupying only two instead of three cache lines. Those changes results in a 5% performance increase on an IPsec test run using pcrypt. Btw. the seq_lock spinlock was never explicitly initialized -- one more reason to get rid of it. Signed-off-by: Mathias Krause <mathias.krause@secunet.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-29padata - Register hotcpu notifier after initializationRichard Weinberger1-6/+6
padata_cpu_callback() takes pinst->lock, to avoid taking an uninitialized lock, register the notifier after it's initialization. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-29padata - share code between CPU_ONLINE and CPU_DOWN_FAILED, same to ↵Chen Gang1-16/+4
CPU_DOWN_PREPARE and CPU_UP_CANCELED Share code between CPU_ONLINE and CPU_DOWN_FAILED, same to CPU_DOWN_PREPARE and CPU_UP_CANCELED. It will fix 2 bugs: "not check the return value of __padata_remove_cpu() and __padata_add_cpu()". "need add 'break' between CPU_UP_CANCELED and CPU_DOWN_FAILED". Signed-off-by: Chen Gang <gang.chen@asianux.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-12-06padata: use __this_cpu_read per-cpu helperShan Wei1-3/+2
For bottom halves off, __this_cpu_read is better. Signed-off-by: Shan Wei <davidshan@tencent.com> Reviewed-by: Christoph Lameter <cl@linux.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Fix cpu hotplugSteffen Klassert1-0/+3
We don't remove the cpu that went offline from our cpumasks on cpu hotplug. This got lost somewhere along the line, so restore it. This fixes a hang of the padata instance on cpu hotplug. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Use the online cpumask as the defaultSteffen Klassert1-4/+4
We use the active cpumask to determine the superset of cpus to use for parallelization. However, the active cpumask is for internal usage of the scheduler and therefore not the appropriate cpumask for these purposes. So use the online cpumask instead. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-29padata: Add a reference to the api documentationSteffen Klassert1-0/+2
Add a reference to the padata api documentation at Documentation/padata.txt Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14padata: Fix race on sequence number wrapSteffen Klassert1-28/+10
When padata_do_parallel() is called from multiple cpus for the same padata instance, we can get object reordering on sequence number wrap because testing for sequence number wrap and reseting the sequence number must happen atomically but is implemented with two atomic operations. This patch fixes this by converting the sequence number from atomic_t to an unsigned int and protect the access with a spin_lock. As a side effect, we get rid of the sequence number wrap handling because the seqence number wraps back to null now without the need to do anything. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-03-14padata: Fix race in the serialization pathSteffen Klassert1-2/+4
When a padata object is queued to the serialization queue, another cpu might process and free the padata object. So don't dereference it after queueing to the serialization queue. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-31kernel: Map most files to use export.h instead of module.hPaul Gortmaker1-1/+1
The changed files were only including linux/module.h for the EXPORT_SYMBOL infrastructure, and nothing else. Revector them onto the isolated export header for faster compile times. Nothing to see here but a whole lot of instances of: -#include <linux/module.h> +#include <linux/export.h> This commit is only changing the kernel dir; next targets will probably be mm, fs, the arch dirs, etc. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-31Fix common misspellingsLucas De Marchi1-4/+4
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-08-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds1-197/+558
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (39 commits) random: Reorder struct entropy_store to remove padding on 64bits padata: update API documentation padata: Remove padata_get_cpumask crypto: pcrypt - Update pcrypt cpumask according to the padata cpumask notifier crypto: pcrypt - Rename pcrypt_instance padata: Pass the padata cpumasks to the cpumask_change_notifier chain padata: Rearrange set_cpumask functions padata: Rename padata_alloc functions crypto: pcrypt - Dont calulate a callback cpu on empty callback cpumask padata: Check for valid cpumasks padata: Allocate cpumask dependend recources in any case padata: Fix cpu index counting crypto: geode_aes - Convert pci_table entries to PCI_VDEVICE (if PCI_ANY_ID is used) pcrypt: Added sysfs interface to pcrypt padata: Added sysfs primitives to padata subsystem padata: Make two separate cpumasks padata: update documentation padata: simplify serialization mechanism padata: make padata_do_parallel to return zero on success padata: Handle empty padata cpumasks ...
2010-07-31padata: Remove padata_get_cpumaskSteffen Klassert1-35/+0
A function that copies the padata cpumasks to a user buffer is a bit error prone. The cpumask can change any time so we can't be sure to have the right cpumask when using this function. A user who is interested in the padata cpumasks should register to the padata cpumask notifier chain instead. Users of padata_get_cpumask are already updated, so we can remove it. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Pass the padata cpumasks to the cpumask_change_notifier chainSteffen Klassert1-1/+2
We pass a pointer to the new padata cpumasks to the cpumask_change_notifier chain. So users can access the cpumasks without the need of an extra padata_get_cpumask function. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Rearrange set_cpumask functionsSteffen Klassert1-50/+67
padata_set_cpumask needs to be protected by a lock. We make __padata_set_cpumasks unlocked and static. So this function can be used by the exported and locked padata_set_cpumask and padata_set_cpumasks functions. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-31padata: Rename padata_alloc functionsSteffen Klassert1-12/+12
We rename padata_alloc to padata_alloc_possible because this function allocates a padata_instance and uses the cpu_possible mask for parallel and serial workers. Also we rename __padata_alloc to padata_alloc to avoid to export underlined functions. Underlined functions are considered to be private to padata. Users are updated accordingly. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Check for valid cpumasksSteffen Klassert1-1/+1
Now that we allow to change the cpumasks from userspace, we have to check for valid cpumasks in padata_do_parallel. This patch adds the necessary check. This fixes a division by zero crash if the parallel cpumask contains no active cpu. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Allocate cpumask dependend recources in any caseSteffen Klassert1-17/+7
The cpumask separation work assumes the cpumask dependend recources present regardless of valid or invalid cpumasks. With this patch we allocate the cpumask dependend recources in any case. This fixes two NULL pointer dereference crashes in padata_replace and in padata_get_cpumask. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-26padata: Fix cpu index countingSteffen Klassert1-0/+1
The counting of the cpu index got lost with a recent commit. This patch restores it. This fixes a hang of the parallel worker threads on cpu hotplug. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19padata: Added sysfs primitives to padata subsystemDan Kruchinin1-9/+146
Added sysfs primitives to padata subsystem. Now API user may embedded kobject each padata instance contains into any sysfs hierarchy. For now padata sysfs interface provides only two objects: serial_cpumask [RW] - cpumask for serial workers parallel_cpumask [RW] - cpumask for parallel workers Signed-off-by: Dan Kruchinin <dkruchinin@acm.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19padata: Make two separate cpumasksDan Kruchinin1-124/+347
The aim of this patch is to make two separate cpumasks for padata parallel and serial workers respectively. It allows user to make more thin and sophisticated configurations of padata framework. For example user may bind parallel and serial workers to non-intersecting CPU groups to gain better performance. Also each padata instance has notifiers chain for its cpumasks now. If either parallel or serial or both masks were changed all interested subsystems will get notification about that. It's especially useful if padata user uses algorithm for callback CPU selection according to serial cpumask. Signed-off-by: Dan Kruchinin <dkruchinin@acm.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: simplify serialization mechanismSteffen Klassert1-52/+19
We count the number of processed objects on a percpu basis, so we need to go through all the percpu reorder queues to calculate the sequence number of the next object that needs serialization. This patch changes this to count the number of processed objects global. So we can calculate the sequence number and the percpu reorder queue of the next object that needs serialization without searching through the percpu reorder queues. This avoids some accesses to memory of foreign cpus. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: make padata_do_parallel to return zero on successSteffen Klassert1-6/+5
To return -EINPROGRESS on success in padata_do_parallel was considered to be odd. This patch changes this to return zero on success. Also the only user of padata, pcrypt is adapted to convert a return of zero to -EINPROGRESS within the crypto layer. This also removes the pcrypt fallback if padata_do_parallel was called on a not running padata instance as we can't handle it anymore. This fallback was unused, so it's save to remove it. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: Handle empty padata cpumasksSteffen Klassert1-11/+50
This patch fixes a bug when the padata cpumask does not intersect with the active cpumask. In this case we get a division by zero in padata_alloc_pd and we end up with a useless padata instance. Padata can end up with an empty cpumask for two reasons: 1. A user removed the last cpu that belongs to the padata cpumask and the active cpumask. 2. The last cpu that belongs to the padata cpumask and the active cpumask goes offline. We introduce a function padata_validate_cpumask to check if the padata cpumask does intersect with the active cpumask. If the cpumasks do not intersect we mark the instance as invalid, so it can't be used. We do not allocate the cpumask dependend recources in this case. This fixes the division by zero and keeps the padate instance in a consistent state. It's not possible to trigger this bug by now because the only padata user, pcrypt uses always the possible cpumask. Reported-by: Dan Kruchinin <dkruchinin@acm.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: Block until the instance is unused on stopSteffen Klassert1-8/+16
This patch makes padata_stop to block until the padata instance is unused. Also we split padata_stop to a locked and a unlocked version. This is in preparation to be able to change the cpumask after a call to patata stop. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14padata: Check for valid padata instance on startSteffen Klassert1-2/+16
This patch introduces the PADATA_INVALID flag which is checked on padata start. This will be used to mark a padata instance as invalid, if the padata cpumask does not intersect with the active cpumask. we change padata_start to return an error if the PADATA_INVALID is set. Also we adapt the only padata user, pcrypt to this change. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-03padata: add parenthesis in MAX_SEQ_NR macroDan Carpenter1-1/+1
MAX_SEQ_NR is used in padata_alloc_pd() like this: pd->max_seq_nr = (MAX_SEQ_NR / num_cpus) * num_cpus - 1; It needs parenthesis or the divide by num_cpus takes precedence over the subtraction. Signed-off-by: Dan Carpenter <error27@gmail.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-27kernel/: convert cpu notifier to return encapsulate errno valueAkinobu Mita1-2/+2
By the previous modification, the cpu notifier can return encapsulate errno value. This converts the cpu notifiers for kernel/*.c Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-19padata: Use get_online_cpus/put_online_cpus in padata_freeSteffen Klassert1-0/+3
Add get_online_cpus/put_online_cpus to ensure that no cpu goes offline during the flushing of the padata percpu queues. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Add some code commentsSteffen Klassert1-11/+57
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Flush the padata queues activelySteffen Klassert1-8/+25
yield was used to wait until all references of the internal control structure in use are dropped before it is freed. This patch implements padata_flush_queues which actively flushes the padata percpu queues in this case. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19padata: Use a timer to handle remaining objects in the reorder queues Steffen Klassert1-7/+18
padata_get_next needs to check whether the next object that need serialization must be parallel processed by the local cpu. This check was wrong implemented and returned always true, so the try_again loop in padata_reorder was never taken. This can lead to object leaks in some rare cases due to a race that appears with the trylock in padata_reorder. The try_again loop was not a good idea after all, because a cpu could take that loop frequently, so we handle this with a timer instead. This patch adds a timer to handle the race that appears with the trylock. If cpu1 queues an object to the reorder queue while cpu2 holds the pd->lock but left the while loop in padata_reorder already, cpu2 can't care for this object and cpu1 exits because it can't get the lock. Usually the next cpu that takes the lock cares for this object too. We need the timer just if this object was the last one that arrives to the reorder queues. The timer function sends it out in this case. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-03padata: Use get_online_cpus/put_online_cpusSteffen Klassert1-0/+13
This patch puts get_online_cpus/put_online_cpus around the places we modify the padata cpumask to ensure that no cpu goes offline during this operation. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-03padata: Initialize the padata queues only for the used cpusSteffen Klassert1-9/+5
padata_alloc_pd set up queues for all possible cpus. This patch changes this to set up the queues just for the used cpus. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-03padata: Remove superfluous might_sleepSteffen Klassert1-10/+0
might_sleep() was placed before mutex_lock() in some places. We remove them because mutex_lock() does might_sleep() too. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-03padata: cpu hotplug code should depend on CONFIG_HOTPLUG_CPUSteffen Klassert1-6/+7
This patch makes the padata cpu hotplug code dependend on CONFIG_HOTPLUG_CPU. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6Herbert Xu1-1/+8
2010-05-03padata: Dont scale the parallel objects with the cpusSteffen Klassert1-1/+1
Scaling the maximum number of objects in the parallel codepath can lead to out of memory problems on bigsmp machines. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-29padata: Section cleanupHenrik Kretzschmar1-2/+2
This patch removes the __cupinit from padata_cpu_callback(), which is refered by the exportet function padata_alloc(). This could lead to problems if CONFIG_HOTPLUG_CPU is disabled, which should happen very often. WARNING: kernel/built-in.o(.text+0x7ffcb): Section mismatch in reference from the function padata_alloc() to the function .cpuinit.text:padata_cpu_callback() The function padata_alloc() references the function __cpuinit padata_cpu_callback(). This is often because padata_alloc lacks a __cpuinit annotation or the annotation of padata_cpu_callback is wrong. Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-03-04padata: Allocate the cpumask for the padata instanceSteffen Klassert1-1/+7
The cpumask of the padata instance was used without allocated. This caused boot crashes if CONFIG_CPUMASK_OFFSTACK is enabled. This patch fixes this by doing proper allocation for this cpumask. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-01-06padata: Generic parallelization/serialization interfaceSteffen Klassert1-0/+690
This patch introduces an interface to process data objects in parallel. The parallelized objects return after serialization in the same order as they were before the parallelization. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>