From nobody Mon Apr 13 04:01:55 2026 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 4fvDHm0SGHz6YCc6 for ; Mon, 13 Apr 2026 04:01:56 +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 "R12" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4fvDHl4d4dz3wBB for ; Mon, 13 Apr 2026 04:01:55 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1776052915; 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=e6RNqDItuLSop19LxWMWCYSHNjf7c2Or6nh1/CveEe0=; b=yZz7EgWJ/SNQ27PaSxCCk6qnBgOkuozNfP8/zolG9op+DFAHfBAzfIT96O2/BycSaU4zDE 7LakA6PozXHWiJaxlt9nav2hWviz5Iqr5VHYM2rhrv1c19JONLf8xUHBUXaShvkGz6v5uy ERaAqdL5cxEkHd+LzjpDSoBmPo6rz6TNH+tluFLl8Qb3CibOXSzJN64jhCKpLnmhWtbMgb f2taUbFYSo1ja09cxkLkvT6noHgLKPKS3AIz+goKCzxqTNw194zvjibljGJ9sv5c1l/XN1 QPAFnZlLdOqu0T6opb3iF0iMz77/h92NilvBoeAoDxswbsLDKxCY2HsGuMHqHg== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1776052915; a=rsa-sha256; cv=none; b=J4xVjO5fQ5vmr+TE1ftcov//K40NKpDtLLDihuNFAcpCW/U1SD2+gzdA8Sp3i1zW71nZs1 VhhuKqL9uuzW0Twtm/bJGnp65du8AILOqScXTG2ZA59RqGHkYmw8eL5koGjwGFDvjxQrDs 6cEIwa+MtNsBO2GIEvgLcwdQHA8hLo08p4zS4cJ8DOdR0QcDQvybayVv7idhDALUpQ05Hl VXhm+8IWM5fCJ/gsIszyfXlF70a54XCi/hv8b0nYQO9t+wnYQa6X2TtA8bjGXq7YlMTdlD AMp0jplYu5JhA6qS1KTVzO1p6AlW3huFINd0C1rfCqFVzDPiHeDiyKhFWrU2Bw== 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=1776052915; 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=e6RNqDItuLSop19LxWMWCYSHNjf7c2Or6nh1/CveEe0=; b=F9lde5U4wUJZEx7QlN35FPc+r+EydWSnTWwz7S1I7ImW/RXCAcbPaqaXFdFay+FWaFeOWD RnZdoq1SJVj7rLFOYkbSDHZGaXdZI8HkwuioNfAJqOwRZ1McWXQ+N0VFaz4tP4+Yxd8Q2W ahfMIwf3163itR9cyGE8p08VsqV7JjL2/ypZOpU9a7ugpSkj5gjlocjuxBt1Iq2Cksl0By AOrmQJng7H63ZFgVax87/MX/aT3wAl5lafNiAyDIppA3IVN7D2koqEOevLEzwej7JiGyIB Egk+O5DSpBzsSsMuAbkiDPl3pNMTscF1Bj4UK0dzXhmpsrA85l/enVK3PUCcJA== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4fvDHl43S1zp1P for ; Mon, 13 Apr 2026 04:01:55 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 1e20c by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 13 Apr 2026 04:01:55 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Kyle Evans Subject: git: 65e1c27b4bab - stable/15 - kqueue: slightly clarify the flow in knlist_cleardel() 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: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kevans X-Git-Repository: src X-Git-Refname: refs/heads/stable/15 X-Git-Reftype: branch X-Git-Commit: 65e1c27b4bab018926837b6106cb16daafd3a7ac Auto-Submitted: auto-generated Date: Mon, 13 Apr 2026 04:01:55 +0000 Message-Id: <69dc6ab3.1e20c.1e93a804@gitrepo.freebsd.org> The branch stable/15 has been updated by kevans: URL: https://cgit.FreeBSD.org/src/commit/?id=65e1c27b4bab018926837b6106cb16daafd3a7ac commit 65e1c27b4bab018926837b6106cb16daafd3a7ac Author: Kyle Evans AuthorDate: 2026-04-09 02:37:00 +0000 Commit: Kyle Evans CommitDate: 2026-04-13 03:12:40 +0000 kqueue: slightly clarify the flow in knlist_cleardel() This is purely a cosmetic change to make it a little easier on the eyes, rather than jumping back to the else branch up top. Re-flow it to use another loop on the outside and just inline the re-lock before we repeat after awaking from fluxwait. The !killkn path should maybe issue a wakeup if there's a thread in KQ_SLEEP so that userland can observe the EOF, but this isn't a practical problem today: pretty much every case of knlist_clear is tied to a file descriptor and called in the close(2) path. As a consequence, potentially affected knotes are almost always destroyed before we even get to knlist_clear(). Reviewed by: kib, markj (cherry picked from commit c6dd40f2d35d596ca60a5d87616c3e4a0fd4f676) --- sys/kern/kern_event.c | 50 +++++++++++++++++++++++++++++--------------------- 1 file changed, 29 insertions(+), 21 deletions(-) diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c index f3723783146a..6e16c40a531c 100644 --- a/sys/kern/kern_event.c +++ b/sys/kern/kern_event.c @@ -2788,31 +2788,39 @@ knlist_cleardel(struct knlist *knl, struct thread *td, int islocked, int killkn) KNL_ASSERT_LOCKED(knl); else { KNL_ASSERT_UNLOCKED(knl); -again: /* need to reacquire lock since we have dropped it */ knl->kl_lock(knl->kl_lockarg); } - SLIST_FOREACH_SAFE(kn, &knl->kl_list, kn_selnext, kn2) { - kq = kn->kn_kq; - KQ_LOCK(kq); - if (kn_in_flux(kn)) { - KQ_UNLOCK(kq); - continue; - } - knlist_remove_kq(knl, kn, 1, 1); - if (killkn) { - kn_enter_flux(kn); - KQ_UNLOCK(kq); - knote_drop_detached(kn, td); - } else { - /* Make sure cleared knotes disappear soon */ - kn->kn_flags |= EV_EOF | EV_ONESHOT; - KQ_UNLOCK(kq); + for (;;) { + /* + * Each pass removes as many knotes as we can before dropping + * into FLUXWAIT. Active knotes are simply detached and either + * freed or converted to one-shot, as the attached subject is + * essentially disappearing. + */ + SLIST_FOREACH_SAFE(kn, &knl->kl_list, kn_selnext, kn2) { + kq = kn->kn_kq; + KQ_LOCK(kq); + if (kn_in_flux(kn)) { + KQ_UNLOCK(kq); + continue; + } + knlist_remove_kq(knl, kn, 1, 1); + if (killkn) { + kn_enter_flux(kn); + KQ_UNLOCK(kq); + knote_drop_detached(kn, td); + } else { + /* Make sure cleared knotes disappear soon */ + kn->kn_flags |= EV_EOF | EV_ONESHOT; + KQ_UNLOCK(kq); + } + kq = NULL; } - kq = NULL; - } - if (!SLIST_EMPTY(&knl->kl_list)) { + if (SLIST_EMPTY(&knl->kl_list)) + break; + /* there are still in flux knotes remaining */ kn = SLIST_FIRST(&knl->kl_list); kq = kn->kn_kq; @@ -2822,7 +2830,7 @@ again: /* need to reacquire lock since we have dropped it */ kq->kq_state |= KQ_FLUXWAIT; msleep(kq, &kq->kq_lock, PSOCK | PDROP, "kqkclr", 0); kq = NULL; - goto again; + knl->kl_lock(knl->kl_lockarg); } if (islocked)