On Sun, Apr 28, 2019 at 03:39:29PM +0800, Ming Lei wrote: > Hi, > > Since supporting to blk-mq, big pre-allocation for sg list is introduced, > this way is very unfriendly wrt. memory consumption. > > There were Red Hat internal reports that some scsi_debug based tests > can't be run any more because of too big pre-allocation. > > Also lpfc users commplained that 1GB+ ram is pre-allocatd for single > HBA. > > sg_alloc_table_chained() is improved to support variant size of 1st > pre-allocated SGL in the 1st patch as suggested by Christoph. > > The other two patches try to address this issue by allocating sg list runtime, > meantime pre-allocating one or two inline sg entries for small IO. This > ways follows NVMe's approach wrt. sg list allocation. > > V4: > - add parameter to sg_alloc_table_chained()/sg_free_table_chained() > directly, and update current callers > > V3: > - improve sg_alloc_table_chained() to accept variant size of > the 1st pre-allocated SGL > - applies the improved sg API to address the big pre-allocation > issue > > V2: > - move inline sg table initializetion into one helper > - introduce new helper for getting inline sg > - comment log fix > > > Ming Lei (3): > lib/sg_pool.c: improve APIs for allocating sg pool > scsi: core: avoid to pre-allocate big chunk for protection meta data > scsi: core: avoid to pre-allocate big chunk for sg list > > drivers/nvme/host/fc.c | 7 ++++--- > drivers/nvme/host/rdma.c | 7 ++++--- > drivers/nvme/target/loop.c | 4 ++-- > drivers/scsi/scsi_lib.c | 31 ++++++++++++++++++++++--------- > include/linux/scatterlist.h | 11 +++++++---- > lib/scatterlist.c | 36 +++++++++++++++++++++++------------- > lib/sg_pool.c | 37 +++++++++++++++++++++++++++---------- > net/sunrpc/xprtrdma/svc_rdma_rw.c | 5 +++-- > 8 files changed, 92 insertions(+), 46 deletions(-) > > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Bart Van Assche <bvanassche@xxxxxxx> > Cc: Ewan D. Milne <emilne@xxxxxxxxxx> > Cc: Hannes Reinecke <hare@xxxxxxxx> > Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> > Cc: Chuck Lever <chuck.lever@xxxxxxxxxx> > Cc: netdev@xxxxxxxxxxxxxxx > Cc: linux-nvme@xxxxxxxxxxxxxxxxxxx Hi Martin, Could you consider to merge this patchset to 5.2 if you are fine? Thanks, Ming
