Author: mjg Date: Mon Oct 7 23:19:09 2019 New Revision: 353293 URL: https://svnweb.freebsd.org/changeset/base/353293
Log: vm: stop trylocking page queues in vm_page_pqbatch_submit About 11 minutes of poudriere -s -j 104 and probing on return value of trylocks reveals that over 10% of attempts fail, which in turn means there are more atomics performed than necessary. Trylocking was there to try preventing migration, but it's not very likely to happen if the lock is uncontested. Reviewed by: markj Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21925 Modified: head/sys/vm/vm_page.c Modified: head/sys/vm/vm_page.c ============================================================================== --- head/sys/vm/vm_page.c Mon Oct 7 22:40:05 2019 (r353292) +++ head/sys/vm/vm_page.c Mon Oct 7 23:19:09 2019 (r353293) @@ -3216,12 +3216,10 @@ vm_page_pqbatch_submit(vm_page_t m, uint8_t queue) critical_exit(); return; } - if (!vm_pagequeue_trylock(pq)) { - critical_exit(); - vm_pagequeue_lock(pq); - critical_enter(); - bq = DPCPU_PTR(pqbatch[domain][queue]); - } + critical_exit(); + vm_pagequeue_lock(pq); + critical_enter(); + bq = DPCPU_PTR(pqbatch[domain][queue]); vm_pqbatch_process(pq, bq, queue); /* _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
