Documentation/padata.txt: fix typos etc.

The pcpumask describes which processors will be used to execute work

The pcpumask describes which processors will be used to execute work

submitted to this instance in parallel. The cbcpumask defines which

submitted to this instance in parallel. The cbcpumask defines which

processors are allowed to use as the serialization callback processor.

processors are allowed to be used as the serialization callback processor.

The workqueue wq is where the work will actually be done; it should be

The workqueue wq is where the work will actually be done; it should be

a multithreaded queue, naturally.

a multithreaded queue, naturally.

Note: Padata maintains two kinds of cpumasks internally. The user supplied

Note: Padata maintains two kinds of cpumasks internally. The user supplied

cpumasks, submitted by padata_alloc/padata_alloc_possible and the 'usable'

cpumasks, submitted by padata_alloc/padata_alloc_possible and the 'usable'

cpumasks. The usable cpumasks are always the subset of active cpus in the

cpumasks. The usable cpumasks are always a subset of active CPUs in the

user supplied cpumasks, these are the cpumasks padata actually use. So

user supplied cpumasks; these are the cpumasks padata actually uses. So

it is legal to supply a cpumask to padata that contains offline cpus.

it is legal to supply a cpumask to padata that contains offline CPUs.

Once a offline cpu in the user supplied cpumask comes online, padata

Once an offline CPU in the user supplied cpumask comes online, padata

is going to use it.

is going to use it.

There are functions for enabling and disabling the instance:

There are functions for enabling and disabling the instance:

These functions are setting or clearing the "PADATA_INIT" flag;

These functions are setting or clearing the "PADATA_INIT" flag;

if that flag is not set, other functions will refuse to work.

if that flag is not set, other functions will refuse to work.

padata_start returns zero on success (flag set) or -EINVAL if the

padata_start returns zero on success (flag set) or -EINVAL if the

padata cpumask contains no active cpu (flag not set).

padata cpumask contains no active CPU (flag not set).

padata_stop clears the flag and blocks until the padata instance

padata_stop clears the flag and blocks until the padata instance

is unused.

is unused.

It's possible to change both cpumasks of a padata instance with

It's possible to change both cpumasks of a padata instance with

padata_set_cpumasks by specifying the cpumasks for parallel execution (pcpumask)

padata_set_cpumasks by specifying the cpumasks for parallel execution (pcpumask)

and for the serial callback function (cbcpumask). padata_set_cpumask is to

and for the serial callback function (cbcpumask). padata_set_cpumask is used to

change just one of the cpumasks. Here cpumask_type is one of PADATA_CPU_SERIAL,

change just one of the cpumasks. Here cpumask_type is one of PADATA_CPU_SERIAL,

PADATA_CPU_PARALLEL and cpumask specifies the new cpumask to use.

PADATA_CPU_PARALLEL and cpumask specifies the new cpumask to use.

To simply add or remove one cpu from a certain cpumask the functions

To simply add or remove one CPU from a certain cpumask the functions

padata_add_cpu/padata_remove_cpu are used. cpu specifies the cpu to add or

padata_add_cpu/padata_remove_cpu are used. cpu specifies the CPU to add or

remove and mask is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL.

remove and mask is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL.

If a user is interested in padata cpumask changes, he can register to

If a user is interested in padata cpumask changes, he can register to

					   struct notifier_block *nblock);

					   struct notifier_block *nblock);

The padata cpumask change notifier notifies about changes of the usable

The padata cpumask change notifier notifies about changes of the usable

cpumasks, i.e. the subset of active cpus in the user supplied cpumask.

cpumasks, i.e. the subset of active CPUs in the user supplied cpumask.

Padata calls the notifier chain with:

Padata calls the notifier chain with:

Here cpumask_change_notifier is registered notifier, notification_mask

Here cpumask_change_notifier is registered notifier, notification_mask

is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL and cpumask is a pointer

is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL and cpumask is a pointer

to a struct padata_cpumask that contains the new cpumask informations.

to a struct padata_cpumask that contains the new cpumask information.

Actually submitting work to the padata instance requires the creation of a

Actually submitting work to the padata instance requires the creation of a

padata_priv structure:

padata_priv structure:

    };

    };

This structure will almost certainly be embedded within some larger

This structure will almost certainly be embedded within some larger

structure specific to the work to be done.  Most its fields are private to

structure specific to the work to be done.  Most of its fields are private to

padata, but the structure should be zeroed at initialisation time, and the

padata, but the structure should be zeroed at initialisation time, and the

parallel() and serial() functions should be provided.  Those functions will

parallel() and serial() functions should be provided.  Those functions will

be called in the process of getting the work done as we will see

be called in the process of getting the work done as we will see