Date: Tue, 27 Mar 2012 14:02:23 +0000 (UTC) From: Fabien Thomas <fabient@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r233544 - head/sys/dev/hwpmc Message-ID: <201203271402.q2RE2Nb7088755@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: fabient Date: Tue Mar 27 14:02:22 2012 New Revision: 233544 URL: http://svn.freebsd.org/changeset/base/233544 Log: Fix random deadlock on pmcstat exit: - Exit the thread when soft shutdown is requested - Wakeup owner thread. Reproduced/tested by looping pmcstat measurement: pmcstat -S instructions -O/tmp/test ls MFC after: 1 week Modified: head/sys/dev/hwpmc/hwpmc_logging.c Modified: head/sys/dev/hwpmc/hwpmc_logging.c ============================================================================== --- head/sys/dev/hwpmc/hwpmc_logging.c Tue Mar 27 14:01:09 2012 (r233543) +++ head/sys/dev/hwpmc/hwpmc_logging.c Tue Mar 27 14:02:22 2012 (r233544) @@ -285,6 +285,7 @@ pmclog_loop(void *arg) if ((lb = TAILQ_FIRST(&po->po_logbuffers)) == NULL) { mtx_unlock_spin(&po->po_mtx); + /* No more buffers and shutdown required. */ if (po->po_flags & PMC_PO_SHUTDOWN) { mtx_unlock(&pmc_kthread_mtx); /* @@ -293,6 +294,7 @@ pmclog_loop(void *arg) */ fo_close(po->po_file, curthread); mtx_lock(&pmc_kthread_mtx); + break; } (void) msleep(po, &pmc_kthread_mtx, PWAIT, @@ -355,6 +357,7 @@ pmclog_loop(void *arg) lb = NULL; } + wakeup_one(po->po_kthread); po->po_kthread = NULL; mtx_unlock(&pmc_kthread_mtx); @@ -653,8 +656,7 @@ pmclog_deconfigure_log(struct pmc_owner ("[pmclog,%d] po=%p no log file", __LINE__, po)); /* stop the kthread, this will reset the 'OWNS_LOGFILE' flag */ - if (po->po_kthread) - pmclog_stop_kthread(po); + pmclog_stop_kthread(po); KASSERT(po->po_kthread == NULL, ("[pmclog,%d] po=%p kthread not stopped", __LINE__, po));
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201203271402.q2RE2Nb7088755>