diff options
| author | Gilad Ben-Yossef <gilad@benyossef.com> | 2012-03-28 14:42:43 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-28 17:14:35 -0700 |
| commit | b3a7e98e024ffa9f7e4554dd720c508015c4a831 (patch) | |
| tree | 50c09e1a47418ba4bb55b11f756bf4d99cf76123 /include | |
| parent | 3fc498f165304dc913f1d13b5ac9ab4c758ee7ab (diff) | |
smp: add func to IPI cpus based on parameter func
Add the on_each_cpu_cond() function that wraps on_each_cpu_mask() and
calculates the cpumask of cpus to IPI by calling a function supplied as a
parameter in order to determine whether to IPI each specific cpu.
The function works around allocation failure of cpumask variable in
CONFIG_CPUMASK_OFFSTACK=y by itereating over cpus sending an IPI a time
via smp_call_function_single().
The function is useful since it allows to seperate the specific code that
decided in each case whether to IPI a specific cpu for a specific request
from the common boilerplate code of handling creating the mask, handling
failures etc.
[akpm@linux-foundation.org: s/gfpflags/gfp_flags/]
[akpm@linux-foundation.org: avoid double-evaluation of `info' (per Michal), parenthesise evaluation of `cond_func']
[akpm@linux-foundation.org: s/CPU/CPUs, use all 80 cols in comment]
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Sasha Levin <levinsasha928@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Avi Kivity <avi@redhat.com>
Acked-by: Michal Nazarewicz <mina86@mina86.org>
Cc: Kosaki Motohiro <kosaki.motohiro@gmail.com>
Cc: Milton Miller <miltonm@bga.com>
Reviewed-by: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/smp.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/linux/smp.h b/include/linux/smp.h index d0adb7898d54..10530d92c04b 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -109,6 +109,15 @@ void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func, void *info, bool wait); /* + * Call a function on each processor for which the supplied function + * cond_func returns a positive value. This may include the local + * processor. + */ +void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), + smp_call_func_t func, void *info, bool wait, + gfp_t gfp_flags); + +/* * Mark the boot cpu "online" so that it can call console drivers in * printk() and can access its per-cpu storage. */ @@ -153,6 +162,21 @@ static inline int up_smp_call_function(smp_call_func_t func, void *info) local_irq_enable(); \ } \ } while (0) +/* + * Preemption is disabled here to make sure the cond_func is called under the + * same condtions in UP and SMP. + */ +#define on_each_cpu_cond(cond_func, func, info, wait, gfp_flags)\ + do { \ + void *__info = (info); \ + preempt_disable(); \ + if ((cond_func)(0, __info)) { \ + local_irq_disable(); \ + (func)(__info); \ + local_irq_enable(); \ + } \ + preempt_enable(); \ + } while (0) static inline void smp_send_reschedule(int cpu) { } #define num_booting_cpus() 1 |