linux-toradex.git/include/linux/percpu_counter.h, branch v2.6.27.39

percpu_counter: new function percpu_counter_sum_and_set

2008-07-11T23:27:31+00:00

Delayed allocation need to check free blocks at every write time.
percpu_counter_read_positive() is not quit accurate. delayed
allocation need a more accurate accounting, but using
percpu_counter_sum_positive() is frequently is quite expensive.

This patch added a new function to update center counter when sum
per-cpu counter, to increase the accurate rate for next
percpu_counter_read() and require less calling expensive
percpu_counter_sum().

Signed-off-by: Mingming Cao 
Signed-off-by: "Theodore Ts'o"

lib: percpu_counter_init_irq

2007-10-17T15:42:44+00:00

provide a way to tell lockdep about percpu_counters that are supposed to be
used from irq safe contexts.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter_init error handling

2007-10-17T15:42:44+00:00

alloc_percpu can fail, propagate that error.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_count_sum()

2007-10-17T15:42:44+00:00

Provide an accurate version of percpu_counter_read.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter_sum_positive

2007-10-17T15:42:44+00:00

 s/percpu_counter_sum/&_positive/

Because its consitent with percpu_counter_read*

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter_set

2007-10-17T15:42:44+00:00

Provide a method to set a percpu counter to a specified value.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: make percpu_counter_add take s64

2007-10-17T15:42:44+00:00

percpu_counter is a s64 counter, make _add consitent.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter variable batch

2007-10-17T15:42:44+00:00

Because the current batch setup has an quadric error bound on the counter,
allow for an alternative setup.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter_sub

2007-10-17T15:42:44+00:00

Hugh spotted that some code does:
  percpu_counter_add(&counter, -unsignedlong)

which, when the amount argument is of type s32, sort-of works thanks to
two's-complement. However when we'd change the type to s64 this breaks on 32bit
machines, because the promotion rules zero extend the unsigned number.

Provide percpu_counter_sub() to hide the s64 cast. That is:
  percpu_counter_sub(&counter, foo)
is equal to:
  percpu_counter_add(&counter, -(s64)foo);

Signed-off-by: Peter Zijlstra 
Cc: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: percpu_counter_add

2007-10-17T15:42:44+00:00

 s/percpu_counter_mod/percpu_counter_add/

Because its a better name, _mod implies modulo.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds