From nobody Thu Aug 3 14:21:52 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4RGrdD3TKkz2twSC; Thu, 3 Aug 2023 14:21:52 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4RGrdD32BYz4LWj; Thu, 3 Aug 2023 14:21:52 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1691072512; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=M0gOLdNUrFiXGi/SVRpxrsxWOd6BQIcxd6Spga8FIYQ=; b=wTXB37NzctkukZrDld6ORcgJyc+lejZJwi4tYKQaJYa9Vjk64gtRsNxX3yddzqaG9ER1Zr vhzp6pd8Z9Hq1SYlQrwHNejyY3pDU+cg5VUYB8TbBcgup9/ckKBTSZnGZsoyq3bSSDz7GA NIQoriCT0g0PK3BaIptK5cjsNXTKux7dzCyH9L2uVSZk63po0BJPGxNQod8nBuSdlJsT1N HWmHNNp8MGbh5dsl2lJPQVKqTrGbbtaEai19rbv8hfUhtzto/lgPxt3e4b6Um9gPIo7GES XTlpGrjIgjouo4QWQmcsHRx9MaBBsw/D2QFWVdLAquKRiRRnfie6PEiT9WSmmw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1691072512; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=M0gOLdNUrFiXGi/SVRpxrsxWOd6BQIcxd6Spga8FIYQ=; b=rGlMOkH5WxwML3JGtk6SVyrZhcaQVtBvdHS2ZH69K5adTOnEOxWPv+7y2Ifn7/tU+nff63 1b2ajLx5/iABrZfNNvJg+/nq4glJ0TpfjdtooB1bOzldbcFXu4OeVRapjroewZw9mO3nIZ IRQZy9TQJfujHD4bKyDemFlbO758Vq8HCMd5j4z7QVYKjco5363fDYfyKZf65qetbgJURe /Vcq+2Ep6Ca5oUruhyn4leJ/toWJE3D4m9L+u3KZQn9XCYL2lsuW/KVVk1AMUGfMO68hx/ IYAfeS5DKjSsLOpkGFhIXoKT26alW3k4idky4DhdJlzlv85CSnJloG+yeHQm3Q== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1691072512; a=rsa-sha256; cv=none; b=sNRtG/wUdEBLePet3PX/emc3e2/0YO9mmw2+7kF+xyrR38j7TcUTHKOx+gNbzMawHaUVUp xjpYT2OquOpPEXmzyYa0njzSilw8lpKZlOezkTUfv8idee2Czy/7PqV4CXhfvSM3t7v/cY RCiR/3VfDZW6N/ocs7NkX0fPFxDHG2ZdUr9r1x1bgN0gNUYakZS5CESqSfWYl9c65RqIOR 8rcizNSzddQ1kkflG8RUO863CWM4eKs1so1kwn2b3DTlRRmyUDkssgUesPUGPLfdhOyd3S t9sIbC9OAnw1M4F7emFISZjeW3A8IX1Dw+foB8SNcdjZegT8+1Fiezqv0rQSsg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4RGrdD25Q8z90j; Thu, 3 Aug 2023 14:21:52 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 373ELqaB022333; Thu, 3 Aug 2023 14:21:52 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 373ELqS8022332; Thu, 3 Aug 2023 14:21:52 GMT (envelope-from git) Date: Thu, 3 Aug 2023 14:21:52 GMT Message-Id: <202308031421.373ELqS8022332@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Doug Moore Subject: git: c9b06fa52776 - main - vm_phys_enqueue_contig: handle npages==0 List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: dougm X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: c9b06fa52776fbf555b9397a8d28a54c957108ec Auto-Submitted: auto-generated The branch main has been updated by dougm: URL: https://cgit.FreeBSD.org/src/commit/?id=c9b06fa52776fbf555b9397a8d28a54c957108ec commit c9b06fa52776fbf555b9397a8d28a54c957108ec Author: Doug Moore AuthorDate: 2023-08-03 14:19:48 +0000 Commit: Doug Moore CommitDate: 2023-08-03 14:19:48 +0000 vm_phys_enqueue_contig: handle npages==0 By letting vm_phys_enqueue_contig handle the case when npages == 0, the callers can stop checking it, and the compiler can stop zero-checking with every call to ffs(). Letting vm_phys_enqueue_contig call vm_phys_enqueue_contig for part of its work also saves a few bytes. The amd64 object code shrinks by 128 bytes. Reviewed by: kib (previous version) Tested by: pho Differential Revision: https://reviews.freebsd.org/D41154 --- sys/vm/vm_phys.c | 76 +++++++++++++++++++++++++++----------------------------- 1 file changed, 36 insertions(+), 40 deletions(-) diff --git a/sys/vm/vm_phys.c b/sys/vm/vm_phys.c index 28f12231e01c..ed358d7cd4a9 100644 --- a/sys/vm/vm_phys.c +++ b/sys/vm/vm_phys.c @@ -72,6 +72,8 @@ __FBSDID("$FreeBSD$"); _Static_assert(sizeof(long) * NBBY >= VM_PHYSSEG_MAX, "Too many physsegs."); +_Static_assert(sizeof(long long) >= sizeof(vm_paddr_t), + "vm_paddr_t too big for ffsll, flsll."); #ifdef NUMA struct mem_affinity __read_mostly *mem_affinity; @@ -690,18 +692,16 @@ vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order, * * The physical page m's buddy must not be free. */ -static void +static vm_page_t vm_phys_enq_range(vm_page_t m, u_int npages, struct vm_freelist *fl, int tail) { - u_int n; int order; - KASSERT(npages > 0, ("vm_phys_enq_range: npages is 0")); KASSERT(((VM_PAGE_TO_PHYS(m) + npages * PAGE_SIZE) & - ((PAGE_SIZE << (fls(npages) - 1)) - 1)) == 0, + ((PAGE_SIZE << fls(npages / 2)) - 1)) == 0, ("vm_phys_enq_range: page %p and npages %u are misaligned", m, npages)); - do { + while (npages > 0) { KASSERT(m->order == VM_NFREEORDER, ("vm_phys_enq_range: page %p has unexpected order %d", m, m->order)); @@ -709,10 +709,10 @@ vm_phys_enq_range(vm_page_t m, u_int npages, struct vm_freelist *fl, int tail) KASSERT(order < VM_NFREEORDER, ("vm_phys_enq_range: order %d is out of range", order)); vm_freelist_add(fl, m, order, tail); - n = 1 << order; - m += n; - npages -= n; - } while (npages > 0); + m += 1 << order; + npages -= 1 << order; + } + return (m); } /* @@ -744,7 +744,7 @@ vm_phys_alloc_npages(int domain, int pool, int npages, vm_page_t ma[]) { struct vm_freelist *alt, *fl; vm_page_t m; - int avail, end, flind, freelist, i, need, oind, pind; + int avail, end, flind, freelist, i, oind, pind; KASSERT(domain >= 0 && domain < vm_ndomains, ("vm_phys_alloc_npages: domain %d is out of range", domain)); @@ -762,20 +762,18 @@ vm_phys_alloc_npages(int domain, int pool, int npages, vm_page_t ma[]) for (oind = 0; oind < VM_NFREEORDER; oind++) { while ((m = TAILQ_FIRST(&fl[oind].pl)) != NULL) { vm_freelist_rem(fl, m, oind); - avail = 1 << oind; - need = imin(npages - i, avail); - for (end = i + need; i < end;) + avail = i + (1 << oind); + end = imin(npages, avail); + while (i < end) ma[i++] = m++; - if (need < avail) { + if (i == npages) { /* - * Return excess pages to fl. Its - * order [0, oind) queues are empty. + * Return excess pages to fl. Its order + * [0, oind) queues are empty. */ - vm_phys_enq_range(m, avail - need, fl, - 1); - return (npages); - } else if (i == npages) + vm_phys_enq_range(m, avail - i, fl, 1); return (npages); + } } } for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) { @@ -785,21 +783,20 @@ vm_phys_alloc_npages(int domain, int pool, int npages, vm_page_t ma[]) NULL) { vm_freelist_rem(alt, m, oind); vm_phys_set_pool(pool, m, oind); - avail = 1 << oind; - need = imin(npages - i, avail); - for (end = i + need; i < end;) + avail = i + (1 << oind); + end = imin(npages, avail); + while (i < end) ma[i++] = m++; - if (need < avail) { + if (i == npages) { /* * Return excess pages to fl. * Its order [0, oind) queues * are empty. */ - vm_phys_enq_range(m, avail - - need, fl, 1); - return (npages); - } else if (i == npages) + vm_phys_enq_range(m, avail - i, + fl, 1); return (npages); + } } } } @@ -1146,7 +1143,7 @@ max_order(vm_page_t m) * because the size of a physical address exceeds the size of * a long. */ - return (min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1, + return (min(ffsll(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1, VM_NFREEORDER - 1)); } @@ -1162,6 +1159,7 @@ vm_phys_enqueue_contig(vm_page_t m, u_long npages) struct vm_freelist *fl; struct vm_phys_seg *seg; vm_page_t m_end; + vm_paddr_t diff, lo; int order; /* @@ -1173,15 +1171,15 @@ vm_phys_enqueue_contig(vm_page_t m, u_long npages) fl = (*seg->free_queues)[m->pool]; m_end = m + npages; /* Free blocks of increasing size. */ - while ((order = max_order(m)) < VM_NFREEORDER - 1 && - m + (1 << order) <= m_end) { - KASSERT(seg == &vm_phys_segs[m->segind], - ("%s: page range [%p,%p) spans multiple segments", - __func__, m_end - npages, m)); - vm_freelist_add(fl, m, order, 1); - m += 1 << order; + lo = VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT; + if (m < m_end && + (diff = lo ^ (lo + npages - 1)) != 0) { + order = min(flsll(diff) - 1, VM_NFREEORDER - 1); + m = vm_phys_enq_range(m, roundup2(lo, 1 << order) - lo, fl, 1); } + /* Free blocks of maximum size. */ + order = VM_NFREEORDER - 1; while (m + (1 << order) <= m_end) { KASSERT(seg == &vm_phys_segs[m->segind], ("%s: page range [%p,%p) spans multiple segments", @@ -1560,10 +1558,8 @@ vm_phys_alloc_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high, vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, oind); } /* Return excess pages to the free lists. */ - if (&m_run[npages] < m) { - fl = (*queues)[VM_FREEPOOL_DEFAULT]; - vm_phys_enq_range(&m_run[npages], m - &m_run[npages], fl, 0); - } + fl = (*queues)[VM_FREEPOOL_DEFAULT]; + vm_phys_enq_range(&m_run[npages], m - &m_run[npages], fl, 0); return (m_run); }