user/sven/linux.git/include/linux/padata.h, branch v4.4.162

padata: make the sequence counter an atomic_t

2013-10-30T04:02:58Z

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 Acked-by: Steffen Klassert Signed-off-by: Herbert Xu

padata: Fix race on sequence number wrap

2012-03-14T09:25:56Z

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 Signed-off-by: Herbert Xu

padata: add missing __percpu markup in include/linux/padata.h

2010-09-03T11:09:46Z

parallel_data->queue is a percpu pointer but was missing __percpu markup. Add it. Signed-off-by: Namhyung Kim Acked-by: Steffen Klassert Signed-off-by: Herbert Xu

padata: Remove padata_get_cpumask

2010-07-31T11:53:06Z

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 Signed-off-by: Herbert Xu

padata: Pass the padata cpumasks to the cpumask_change_notifier chain

2010-07-31T11:53:05Z

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 Signed-off-by: Herbert Xu

padata: Rearrange set_cpumask functions

2010-07-31T11:53:04Z

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 Signed-off-by: Herbert Xu

padata: Rename padata_alloc functions

2010-07-31T11:53:04Z

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 Signed-off-by: Herbert Xu

padata: Added sysfs primitives to padata subsystem

2010-07-19T05:50:19Z

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 Signed-off-by: Herbert Xu

padata: Make two separate cpumasks

2010-07-19T05:50:19Z

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 Signed-off-by: Herbert Xu

padata: simplify serialization mechanism

2010-07-14T12:29:30Z

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 Signed-off-by: Herbert Xu