On 08/10/2010 12:06 AM, Pekka Enberg wrote: > On Mon, Aug 9, 2010 at 8:26 PM, Nitin Gupta <ngupta@xxxxxxxxxx> wrote: >> Currently, the user has to explicitly write a positive value to >> initstate sysfs node before the device can be used. This event >> triggers allocation of per-device metadata like memory pool, >> table array and so on. >> >> We do not pre-initialize all zram devices since the 'table' array, >> mapping disk blocks to compressed chunks, takes considerable amount >> of memory (8 bytes per page). So, pre-initializing all devices will >> be quite wasteful if only few or none of the devices are actually >> used. >> >> This explicit device initialization from user is an odd requirement and >> can be easily avoided. We now initialize the device when first write is >> done to the device. >> >> Signed-off-by: Nitin Gupta <ngupta@xxxxxxxxxx> > > AFAICT, most hardware block device drivers do things like this in the > probe function. Why can't we do that for zram as well and drop the > ->init_done and ->init_lock parts? > I think probe is only for PCI devices? Maybe should hook into open function in struct block_device_operations. That way, we can also drop init_done and init_lock parts. Thanks, Nitin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>