From nobody Wed Mar 02 21:57:16 2022 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 D564119E064F; Wed, 2 Mar 2022 21:57:17 +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 4K87JF2D4tz3KGb; Wed, 2 Mar 2022 21:57:17 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1646258237; 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=fCo2PqqUOGmJapFcSUd92M0RcLl8uLaVLQuMOzQ7XUk=; b=C6XtHmKQwA5IHXT5lRYhQ/qPJbnTXNuO7BEra+0M4+6kCWK7K2w56SqpXcMgxSp/QdGBGm wRIy2iy8gE0dpXEsta7AgfxSCv98Jub93o+321KcxSTHXdA+DmvBz1mayZ52QxBEvdm0Oh 2uJmWX/U9eB2h7C3zs6mCAGRrF8Y7Ai++iUapd788mOaEDqWOaUC3Z6tY/ROI2OIAb8d3W CWniMITuv6HNXmNKUBcwA3resLmmP2kVew+VQCWxlzmoXC5YlzhrRBYuJPZm2XuMhGgGER F1CSW6+x26PDjb+h4j/TQtRX3Qc5dHbcBhkE9YUF0p0k0Zu3dI7r6e2So5xCsw== 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 0908637C4; Wed, 2 Mar 2022 21:57:17 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 222LvGsp065018; Wed, 2 Mar 2022 21:57:16 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 222LvGbX065017; Wed, 2 Mar 2022 21:57:16 GMT (envelope-from git) Date: Wed, 2 Mar 2022 21:57:16 GMT Message-Id: <202203022157.222LvGbX065017@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Eric van Gyzen Subject: git: d89523644308 - stable/13 - libprocstat kstack: fix race with thread creation 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: vangyzen X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: d89523644308afd24d47ca3dcf4098d0a719e919 Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1646258237; 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=fCo2PqqUOGmJapFcSUd92M0RcLl8uLaVLQuMOzQ7XUk=; b=HhcmFyV97lcTcGFAVfKliPVP4T8Kzp0D4O0SwOY/8QP56YKV/tVE46refnbUPktgOcMWtP j/c9rM+J+++o/u+78M7EkKezcLB2FK/jjwKGlWbpNAFmc7nz3IDITjRWKpngUr1Sy2CsWW R2rWdQ/g5w6ZPqofcjxsMlyau8MfiYDsOTFYPkexPCcxK1U+va3xdKyzzzypG45Xu1WAsx OBBr5HSJx3qI/QeojVUTnH/SciNDFf+W+AWMshn156V1KIyvycBLkWlMvt5+oBqQgViEPE AwODe/KSLZuSztvsvFjIzJ+4pa+Og77eBPgcwno3cCUugEEv6nXy6XLXYDhYvA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1646258237; a=rsa-sha256; cv=none; b=jysiOmonjSpxD9GKkxAEhoZ2ojGpB3pkEw44vPd4c3Eq+xUKHwTrlMjzv7XKfhTEMorxR/ l1/2mHiGRAr/nr0IPfox4coKR8nhV3D/TMDKI3S/gZ29flyXcP/jSQPszzPgJKoKRuQzVj 3qaxP/tljnSAcnVr9TOmwpXwW67qTGgtrMfpTpCm5UtlmamRGvGNl6np9c3eCOndvp+c93 SH59EwNe2YE7ZCBKfKnbNlZSQFS1Sxmp7ah3aoKfyIlfYo9dj2jJgwTMmU1HB+ZxRIRvQi JbAr85IRJKb1JAwQY33Zi/BM10nZLm0qR3fN6MoZWJSEJwK1w2H5AfmjIoGb5A== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N The branch stable/13 has been updated by vangyzen: URL: https://cgit.FreeBSD.org/src/commit/?id=d89523644308afd24d47ca3dcf4098d0a719e919 commit d89523644308afd24d47ca3dcf4098d0a719e919 Author: Eric van Gyzen AuthorDate: 2021-05-27 16:33:22 +0000 Commit: Eric van Gyzen CommitDate: 2022-03-02 21:56:30 +0000 libprocstat kstack: fix race with thread creation When collecting kernel stacks for a target process, if the process adds a thread between the two calls to sysctl, ignore the additional threads. Previously, procstat would print only a useless error message. Now, it prints a consistent snapshot of the stacks. We know that snapshot is already stale, but it could still be stale even with a more complex fix to reallocate and retry, so such a fix is hardly worth the effort. Reported by: Daniel.Mitchell@emc.com MFC after: 1 week Sponsored by: Dell EMC Isilon (cherry picked from commit 427f12f150e875c40acb84f292a80bfa0b90a1a2) --- lib/libprocstat/libprocstat.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/libprocstat/libprocstat.c b/lib/libprocstat/libprocstat.c index 89896a813888..9409fb0e1964 100644 --- a/lib/libprocstat/libprocstat.c +++ b/lib/libprocstat/libprocstat.c @@ -2610,7 +2610,8 @@ procstat_getkstack_sysctl(pid_t pid, int *cntp) warn("malloc(%zu)", len); return (NULL); } - if (sysctl(name, nitems(name), kkstp, &len, NULL, 0) == -1) { + if (sysctl(name, nitems(name), kkstp, &len, NULL, 0) == -1 && + errno != ENOMEM) { warn("sysctl: kern.proc.pid: %d", pid); free(kkstp); return (NULL);