From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 5FAB29AF3A for ; Wed, 24 May 2023 12:54:09 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 4120D1D23C for ; Wed, 24 May 2023 12:54:09 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Wed, 24 May 2023 12:54:08 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id DB14346DA0 for ; Wed, 24 May 2023 12:54:07 +0200 (CEST) From: Fiona Ebner To: pve-devel@lists.proxmox.com Date: Wed, 24 May 2023 12:54:00 +0200 Message-Id: <20230524105403.98049-2-f.ebner@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230524105403.98049-1-f.ebner@proxmox.com> References: <20230524105403.98049-1-f.ebner@proxmox.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.049 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_SCC_BODY_TEXT_LINE -0.01 - Subject: [pve-devel] [RFC qemu-server 1/2] qmeventd: extract vmid from cgroup file instead of cmdline X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 May 2023 10:54:09 -0000 This is the single remaining user of the id argument. The id argument is a Proxmox-specific extension to QEMU, which we'd like to drop to reduce our differences with upstream QEMU. Signed-off-by: Fiona Ebner --- qmeventd/qmeventd.c | 50 +++++++++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 20 deletions(-) diff --git a/qmeventd/qmeventd.c b/qmeventd/qmeventd.c index a843da5f..921c0dca 100644 --- a/qmeventd/qmeventd.c +++ b/qmeventd/qmeventd.c @@ -75,14 +75,13 @@ get_pid_from_fd(int fd) } /* - * reads the vmid from /proc//cmdline - * after the '-id' argument + * parses the vmid from the qemu.slice entry of /proc//cgroup */ static unsigned long get_vmid_from_pid(pid_t pid) { char filename[32] = { 0 }; - int len = snprintf(filename, sizeof(filename), "/proc/%d/cmdline", pid); + int len = snprintf(filename, sizeof(filename), "/proc/%d/cgroup", pid); if (len < 0) { fprintf(stderr, "error during snprintf for %d: %s\n", pid, strerror(errno)); @@ -99,41 +98,52 @@ get_vmid_from_pid(pid_t pid) } unsigned long vmid = 0; - ssize_t rc = 0; char *buf = NULL; size_t buflen = 0; - while ((rc = getdelim(&buf, &buflen, '\0', fp)) >= 0) { - if (!strcmp(buf, "-id")) { - break; + + while (getline(&buf, &buflen, fp) >= 0) { + char *cgroup_path = strrchr(buf, ':'); + if (!cgroup_path) { + fprintf(stderr, "unexpected cgroup entry %s\n", buf); + goto ret; } - } + cgroup_path++; - if (rc < 0) { - goto err; - } + if (strncmp(cgroup_path, "/qemu.slice", 11)) { + continue; + } - if (getdelim(&buf, &buflen, '\0', fp) >= 0) { - if (buf[0] == '-' || buf[0] == '\0') { - fprintf(stderr, "invalid vmid %s\n", buf); + char *vmid_start = strrchr(buf, '/'); + if (!vmid_start) { + fprintf(stderr, "unexpected cgroup entry %s\n", buf); + goto ret; + } + vmid_start++; + + if (vmid_start[0] == '-' || vmid_start[0] == '\0') { + fprintf(stderr, "invalid vmid in cgroup entry %s\n", buf); goto ret; } errno = 0; char *endptr = NULL; - vmid = strtoul(buf, &endptr, 10); + vmid = strtoul(vmid_start, &endptr, 10); if (errno != 0) { + fprintf(stderr, "error parsing vmid for %d: %s\n", pid, strerror(errno)); vmid = 0; - goto err; - } else if (*endptr != '\0') { - fprintf(stderr, "invalid vmid %s\n", buf); + } else if (*endptr != '.') { + fprintf(stderr, "unexpected cgroup entry %s\n", buf); vmid = 0; } goto ret; } -err: - fprintf(stderr, "error parsing vmid for %d: %s\n", pid, strerror(errno)); + if (errno) { + fprintf(stderr, "error parsing vmid for %d: %s\n", pid, strerror(errno)); + } else { + fprintf(stderr, "error parsing vmid for %d: no qemu.slice cgroup entry\n", pid); + } ret: free(buf); -- 2.39.2