From 2d3854a37e8b767a51aba38ed6d22817b0631e33 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 5 Nov 2008 13:39:10 +1100 Subject: cpumask: introduce new API, without changing anything Impact: introduce new APIs We want to deprecate cpumasks on the stack, as we are headed for gynormous numbers of CPUs. Eventually, we want to head towards an undefined 'struct cpumask' so they can never be declared on stack. 1) New cpumask functions which take pointers instead of copies. (cpus_* -> cpumask_*) 2) Several new helpers to reduce requirements for temporary cpumasks (cpumask_first_and, cpumask_next_and, cpumask_any_and) 3) Helpers for declaring cpumasks on or offstack for large NR_CPUS (cpumask_var_t, alloc_cpumask_var and free_cpumask_var) 4) 'struct cpumask' for explicitness and to mark new-style code. 5) Make iterator functions stop at nr_cpu_ids (a runtime constant), not NR_CPUS for time efficiency and for smaller dynamic allocations in future. 6) cpumask_copy() so we can allocate less than a full cpumask eventually (for alloc_cpumask_var), and so we can eliminate the 'struct cpumask' definition eventually. 7) work_on_cpu() helper for doing task on a CPU, rather than saving old cpumask for current thread and manipulating it. 8) smp_call_function_many() which is smp_call_function_mask() except taking a cpumask pointer. Note that this patch simply introduces the new functions and leaves the obsolescent ones in place. This is to simplify the transition patches. Signed-off-by: Rusty Russell Signed-off-by: Ingo Molnar --- include/linux/smp.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux/smp.h') diff --git a/include/linux/smp.h b/include/linux/smp.h index 2e4d58b..3f9a600 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -64,8 +64,17 @@ extern void smp_cpus_done(unsigned int max_cpus); * Call a function on all other processors */ int smp_call_function(void(*func)(void *info), void *info, int wait); +/* Deprecated: use smp_call_function_many() which uses a cpumask ptr. */ int smp_call_function_mask(cpumask_t mask, void(*func)(void *info), void *info, int wait); + +static inline void smp_call_function_many(const struct cpumask *mask, + void (*func)(void *info), void *info, + int wait) +{ + smp_call_function_mask(*mask, func, info, wait); +} + int smp_call_function_single(int cpuid, void (*func) (void *info), void *info, int wait); void __smp_call_function_single(int cpuid, struct call_single_data *data); -- cgit v1.1