Re: [PATCH 2/2] scsi: core: avoid to pre-allocate big chunk for sg list

[Bart Van Assche <bvanassche@xxxxxxx>]

On Tue, 2019-04-23 at 18:32 +-0800, Ming Lei wrote:
+AD4  +ACM-define  SCSI+AF8-INLINE+AF8-PROT+AF8-SG+AF8-CNT  1
+AD4  
+AD4 +-+ACM-define  SCSI+AF8-INLINE+AF8-SG+AF8-CNT  2

So this patch inserts one kmalloc() and one kfree() call in the hot path
for every SCSI request with more than two elements in its scatterlist? Isn't
+ACI-2+ACI too low? Or in other words, what is the performance impact of this patch
for a real-world workload?

Thanks,

Bart.