On Sat, Nov 6, 2010 at 2:09 AM, Rajat Sharma <fs.rajat@xxxxxxxxx> wrote: >> as i know,kmalloc is based on kmem_cache_alloc ,so what's the different? > kmalloc uses the generic slab caches available to any kernel code. so your > module will share slab cache with other components in kernel, but if you > specifically want a better slab cache management dedicated to your module > only, that too for a specific type of objects, use the lower function i.e. > kmem_cache_alloc, it will allocate objects from a dedicated slab cache for > your module objects only, you must create the slab cache by calling > kmem_cache_create before allocating any object. kmem_cache_create takes > sizeof your object you want to create slab of, a name which appears in > /proc/slabinfo and flags to govern behavior of your slab cache. > Rajat My two cents to add to the fine comment above, which re probably not even worth that much, but your getting for free :) If you are asking this question I would probably guess you should just stick to kmalloc, that sounds rude, but I say it with all respect. Unless you are creating your own subsystem(or complex driver) and will be responsible for allocating a lot of one specific data structure there is no reason to create your own cache. Even in the driver case you will often know ahead of time the number of data structures to preallocate and just use those in a ring buffer or similar. -- john -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
