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2010-07-26padata: Fix cpu index countingSteffen Klassert
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 Kruchinin
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 Kruchinin
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Carpenter
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>
2010-05-19padata: Use get_online_cpus/put_online_cpus in padata_freeSteffen Klassert
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Klassert
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 Xu
2010-05-03padata: Dont scale the parallel objects with the cpusSteffen Klassert
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 Heo
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 Kretzschmar
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 Klassert
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 Klassert
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>