From owner-svn-src-all@freebsd.org Tue Mar 12 19:33:26 2019 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 13372153C112; Tue, 12 Mar 2019 19:33:26 +0000 (UTC) (envelope-from kib@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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AB3CA825B6; Tue, 12 Mar 2019 19:33:25 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 972E927501; Tue, 12 Mar 2019 19:33:25 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x2CJXPch044127; Tue, 12 Mar 2019 19:33:25 GMT (envelope-from kib@FreeBSD.org) Received: (from kib@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x2CJXPTN044126; Tue, 12 Mar 2019 19:33:25 GMT (envelope-from kib@FreeBSD.org) Message-Id: <201903121933.x2CJXPTN044126@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: kib set sender to kib@FreeBSD.org using -f From: Konstantin Belousov Date: Tue, 12 Mar 2019 19:33:25 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r345078 - head/sys/dev/hwpmc X-SVN-Group: head X-SVN-Commit-Author: kib X-SVN-Commit-Paths: head/sys/dev/hwpmc X-SVN-Commit-Revision: 345078 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: AB3CA825B6 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.95 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.997,0]; NEURAL_HAM_SHORT(-0.96)[-0.955,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Mar 2019 19:33:26 -0000 Author: kib Date: Tue Mar 12 19:33:25 2019 New Revision: 345078 URL: https://svnweb.freebsd.org/changeset/base/345078 Log: hwpmc/core: Adopt to upcoming Skylake TSX errata. The forthcoming microcode update will fix a TSX bug by clobbering PMC3 when TSX instructions are executed (even speculatively). There is an alternate mode where CPU executes all TSX instructions by aborting them, in which case PMC3 is still available to OS. Any code that correctly uses TSX must be ready to handle abort anyway. Since it is believed that FreeBSD population of hwpmc(4) users is significantly larger than the population of TSX users, switch the microcode into TSX abort mode whenever a pmc is allocated, and back to bug avoidance mode when the last pmc is deallocated. Sponsored by: The FreeBSD Foundation MFC after: 1 week Modified: head/sys/dev/hwpmc/hwpmc_core.c Modified: head/sys/dev/hwpmc/hwpmc_core.c ============================================================================== --- head/sys/dev/hwpmc/hwpmc_core.c Tue Mar 12 19:08:41 2019 (r345077) +++ head/sys/dev/hwpmc/hwpmc_core.c Tue Mar 12 19:33:25 2019 (r345078) @@ -37,6 +37,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include @@ -103,6 +104,9 @@ static int core_iap_width; static int core_iap_npmc; static int core_iap_wroffset; +static u_int pmc_alloc_refs; +static bool pmc_tsx_force_abort_set; + static int core_pcpu_noop(struct pmc_mdep *md, int cpu) { @@ -216,6 +220,15 @@ iaf_reload_count_to_perfctr_value(pmc_value_t rlc) return (1ULL << core_iaf_width) - rlc; } +static void +tweak_tsx_force_abort(void *arg) +{ + u_int val; + + val = (uintptr_t)arg; + wrmsr(MSR_TSX_FORCE_ABORT, val); +} + static int iaf_allocate_pmc(int cpu, int ri, struct pmc *pm, const struct pmc_op_pmcallocate *a) @@ -253,6 +266,12 @@ iaf_allocate_pmc(int cpu, int ri, struct pmc *pm, if (ev == 0x0 && umask == 0x3 && ri != 2) return (EINVAL); + pmc_alloc_refs++; + if ((cpu_stdext_feature3 & CPUID_STDEXT3_TSXFA) != 0 && + !pmc_tsx_force_abort_set) { + pmc_tsx_force_abort_set = true; + smp_rendezvous(NULL, tweak_tsx_force_abort, NULL, (void *)1); + } flags = 0; if (config & IAP_OS) @@ -388,6 +407,12 @@ iaf_release_pmc(int cpu, int ri, struct pmc *pmc) KASSERT(core_pcpu[cpu]->pc_corepmcs[ri + core_iaf_ri].phw_pmc == NULL, ("[core,%d] PHW pmc non-NULL", __LINE__)); + + MPASS(pmc_alloc_refs > 0); + if (pmc_alloc_refs-- == 1 && pmc_tsx_force_abort_set) { + pmc_tsx_force_abort_set = false; + smp_rendezvous(NULL, tweak_tsx_force_abort, NULL, (void *)0); + } return (0); }