> -----Original Message----- > From: Mike Christie [mailto:michaelc@xxxxxxxxxxx] > Qi, Yanling wrote: > Yeah, this problem should occur in the upstream open-iscsi iscsi code. > open-iscsi works very similar to linux-scsi where it just sends pages > around with sock->ops-sendpage, and it looks like sg uses > __get_free_pages in RHEL's kernel and upstream it uses alloc_pages so > unless there was a change in those functions or the network layer then > we should have a similar problem. [Qi, Yanling] Mike, I tried the same test on a SLES10SP1 with open-iscsi driver (lk 2.6.16.37-0.23). It works fine. What happens is that both "alloc_pages()" and "__get_free_pages()" will set page_count to 1 for base page and sub-pages. Because page_count =1, the subpages will not be recycled. It seems the mm code has changed alloc_pages and __get_free_pages()'s behavior along the way from 2.6.9 to 2.6.16. Therefore, we don't have an issue in the upstream kernel and RHEL5. 0 page:ffff81007f8da240 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 1 page:ffff81007f8da278 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 2 page:ffff81007f8da2b0 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 3 page:ffff81007f8da2e8 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 4 page:ffff81007f8da320 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 5 page:ffff81007f8da358 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 6 page:ffff81007f8da390 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 7 page:ffff81007f8da3c8 flags:0x0100000000004000 mapping:0000000000000000 mapcount:0 count:1 Thanks, Yanling - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
