From nobody Wed Feb 19 09:16:35 2025 X-Original-To: dev-commits-src-main@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 4YyW3m4BZvz5p4LR; Wed, 19 Feb 2025 09:16:36 +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 "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4YyW3l75nRz3FBj; Wed, 19 Feb 2025 09:16:35 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1739956596; 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=A1tPIbhmmVax8iKi8yBlfs2iCIUM3H8LOOFxg3woZ5w=; b=s9YNe/M7dWROzhk5KKVGs93QCDIazdoFpXWxilid3cCwCtHiY6UyNj/nj/CtXk0Kz3bolt 5esqdT8Zbr98TwLh2Y8qmWNoahyI4aIDCwc04LtYaegX1R0S+womHR7fDUy2QE2TMHJwXO HGw+5x8IDDoZkGe+GdBAukDi4Y0J7HZTAxTa1vAhVXns/Wg5rO5DRkPwaO+6c4LrkE5Gp1 6eBhsuL0HD+AkMnGFdL4+KEhqhRUzvS4HKp+rYZaPkQH5EN/qysuMRSyJQ7RxmHoRqPII/ g2zZl6rI0RbDjtsPM3vfc++0XpVsrBPPoWnx1+3+UwZ2Vlw/HUM8xQ5z8gkkfQ== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1739956596; a=rsa-sha256; cv=none; b=Rh1zKDC5M/Zx1RgSUGz6QLmCg3szk6Kht8zvl+/vHYR0LLtzodo7XjHO1Sp2InT3jHzNig CY6W/eA0SvbtP8KuUNCQW/APullefAj73vWf4BLTyo0YBn9mvTAr7Vroz1aaJCPgAEKp3m KBoe2V6nYClcg6Iis71r2FbHkD4YUHHHgRYrvuYAUFuRwmzkKSDXbJUMMs4O7jwqiZD1z5 9vFcRDsGLqDC0magL9opLdOjvx6WHwxD3Gs1B0BiBpj5ou0KG0cL6jE0gbOAt6QhH5MHZ8 dpTB8bPV5hiSaJ4z1PFMvKFkIAfoHZ7u5OKukVXvzYq/Y6bdaio0dC3rFv2lvQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1739956596; 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=A1tPIbhmmVax8iKi8yBlfs2iCIUM3H8LOOFxg3woZ5w=; b=lQQ9RzrqiICwTBQePdUpodpSZ2TfkjkaN4oF68pC29Ta2rkOL/i0T/Ujka0XMoJ1FP3UuT 51Dpl2GNcJxuuIGUGqq5N+D8ig1tFby55FjX/F0BRERPp5TC3vXlQeUO0mNTW+FBg92qNe 0gdZ9N3pUqtWnTDK/MRGoEkzp8/3bUcKd4PMB3Ecivtb+JqJiKwpyqw9IkPiKuiBJxdXKY K7KsTjz7wsFau8umJBOpIYcVtQL7lI+degWlV69mYuyC6mTs1MHl4TNVZ5c8b93v7tEMNp 8Asw89CjquQcHpTNeoKO3wcm3uaye9Fg40o2Km6Y/dKn7402K/PpcEe0jj5kEQ== 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 4YyW3l5S0Xz10bp; Wed, 19 Feb 2025 09:16:35 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 51J9GZBG063943; Wed, 19 Feb 2025 09:16:35 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 51J9GZqJ063940; Wed, 19 Feb 2025 09:16:35 GMT (envelope-from git) Date: Wed, 19 Feb 2025 09:16:35 GMT Message-Id: <202502190916.51J9GZqJ063940@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: c301c5841f9f - main - pctrie: unlock node store in remove List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@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: c301c5841f9f5ca3a53a68019115b23ae0ef64a8 Auto-Submitted: auto-generated The branch main has been updated by dougm: URL: https://cgit.FreeBSD.org/src/commit/?id=c301c5841f9f5ca3a53a68019115b23ae0ef64a8 commit c301c5841f9f5ca3a53a68019115b23ae0ef64a8 Author: Doug Moore AuthorDate: 2025-02-19 09:15:30 +0000 Commit: Doug Moore CommitDate: 2025-02-19 09:15:30 +0000 pctrie: unlock node store in remove In pctrie_remove(), if the removal of an item leaves an internal node with one child, then there are two calls to pctrie_node_store(). Only the second of these two needs to be stored with PCTRIE_LOCKED synchronization. Eliminate pointless synchronization for the first node_store in that case. Reviewed by: markj Differential Revision: https://reviews.freebsd.org/D49033 --- sys/kern/subr_pctrie.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/sys/kern/subr_pctrie.c b/sys/kern/subr_pctrie.c index a17c386a6e24..03cf3e1e5990 100644 --- a/sys/kern/subr_pctrie.c +++ b/sys/kern/subr_pctrie.c @@ -834,13 +834,14 @@ static void pctrie_remove(struct pctrie *ptree, struct pctrie_node *node, uint64_t index, struct pctrie_node **freenode) { + smr_pctnode_t *parentp; struct pctrie_node *child; int slot; *freenode = NULL; + parentp = pctrie_child(ptree, node, index); if (node == NULL) { - pctrie_node_store(pctrie_root(ptree), - PCTRIE_NULL, PCTRIE_LOCKED); + pctrie_node_store(parentp, PCTRIE_NULL, PCTRIE_LOCKED); return; } slot = pctrie_slot(node, index); @@ -848,20 +849,22 @@ pctrie_remove(struct pctrie *ptree, struct pctrie_node *node, uint64_t index, ("%s: bad popmap slot %d in node %p", __func__, slot, node)); node->pn_popmap ^= 1 << slot; - pctrie_node_store(&node->pn_child[slot], PCTRIE_NULL, PCTRIE_LOCKED); - if (!powerof2(node->pn_popmap)) + if (!powerof2(node->pn_popmap)) { + pctrie_node_store(parentp, PCTRIE_NULL, PCTRIE_LOCKED); return; + } + pctrie_node_store(parentp, PCTRIE_NULL, PCTRIE_UNSERIALIZED); KASSERT(node->pn_popmap != 0, ("%s: bad popmap all zeroes", __func__)); slot = ffs(node->pn_popmap) - 1; + *freenode = node; child = pctrie_node_load(&node->pn_child[slot], NULL, PCTRIE_LOCKED); KASSERT(child != PCTRIE_NULL, ("%s: bad popmap slot %d in node %p", __func__, slot, node)); - *freenode = node; node = pctrie_parent(node); if (!pctrie_isleaf(child)) pctrie_setparent(child, node); - pctrie_node_store(pctrie_child(ptree, node, index), child, - PCTRIE_LOCKED); + parentp = pctrie_child(ptree, node, index); + pctrie_node_store(parentp, child, PCTRIE_LOCKED); } /*