IDR_PRELOAD(9) Basic Kernel Library Functions IDR_PRELOAD(9)
NAME
idr_preload - preload for idr_alloc
SYNOPSIS
void idr_preload(gfp_t gfp_mask);
ARGUMENTS
gfp_mask
allocation mask to use for preloading
DESCRIPTION
Preload per-cpu layer buffer for idr_alloc. Can only be used from process context and each idr_preload invocation should be matched with
idr_preload_end. Note that preemption is disabled while preloaded.
The first idr_alloc in the preloaded section can be treated as if it were invoked with gfp_mask used for preloading. This allows using more
permissive allocation masks for idrs protected by spinlocks.
For example, if idr_alloc below fails, the failure can be treated as if idr_alloc were called with GFP_KERNEL rather than GFP_NOWAIT.
idr_preload(GFP_KERNEL); spin_lock(lock);
id = idr_alloc(idr, ptr, start, end, GFP_NOWAIT);
spin_unlock(lock); idr_preload_end; if (id < 0) error;
COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 IDR_PRELOAD(9)
