From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-4192269-1516208162-2-3372419211806216409 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='com', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-api-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1516208160; b=PGm73lACKc01a1SBVMBm0PfnR5Mw4lNLmy16Oalhk0A/UEA xgIqovzIF2QOXs075sW/R5aZVAI0zwDsyPvvLR9oLNMFa9jyMT92xnwP+yU0Rzhe HCfZ3wLbUeosTrsryOO5iBfc4Qijcn8hGhWni1XLv4bo1HHH8s/mf/ouVxq6zKu3 bKUPPiT/sFsmCo3Q4KfaGosQzuw64nIYEl4xD+PXzCj9YkGVpRQ0Me0RyTiN7Plj QimqRUXwR9d/gNnMN4lC3wuqryY+fuMjmW4YgFq//rlTVuvjaKn3Tuo8fNUpcFGu G79v4V04CRcK210CgAwlbRkFklhvJxJdKkPtd0w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id:sender :list-id; s=arctest; t=1516208160; bh=EHauHeKBOJjhtPgvHImgrdRCP6 m1zOdqKpKEDmNw21Q=; b=SzADBiarG5dlPwPmmT9rVMwFzGfOJAqDjd9gT5wfHo S953QH4tR+uBTT9iL6Cmcw2PbOe+p453VxqXEZcxfFoMo/wbqai9tiPGJ1fXMBKV 6fZFGxcS3gf3jCOJ/YO+uNTDsGrza/z++7jtx1x7j/cqbMgLA/aZCR+tNW82wLrQ f41s/VPpovv2OzAvoa309S/n6aJeLhR4mXsnFlCAJnlKaJeuxYpv0EgkSPgtFvfK OnUbqP4gia9udVDA9UsXaa4RCy06cTPgSABn4U3aPmF0Qb55ERb3O/QAIfXSvLEC dLRiEb/shz7p3v/40zz8nr6bZZ1iI/n1b6INUHFzkivQ== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=efficios.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=efficios.com header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=efficios.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=efficios.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753777AbeAQQz6 (ORCPT ); Wed, 17 Jan 2018 11:55:58 -0500 Received: from mail.efficios.com ([167.114.142.141]:46142 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753633AbeAQQz5 (ORCPT ); Wed, 17 Jan 2018 11:55:57 -0500 From: Mathieu Desnoyers To: Ingo Molnar , Peter Zijlstra , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Andy Lutomirski , "Paul E . McKenney" , Boqun Feng , Andrew Hunter , Maged Michael , Avi Kivity , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Dave Watson , "H . Peter Anvin" , Andrea Parri , Russell King , Greg Hackmann , Will Deacon , David Sehr , Linus Torvalds , x86@kernel.org, Mathieu Desnoyers Subject: [PATCH for 4.16 00/11] membarrier updates for 4.16 Date: Wed, 17 Jan 2018 11:54:47 -0500 Message-Id: <20180117165458.13330-1-mathieu.desnoyers@efficios.com> X-Mailer: git-send-email 2.11.0 Sender: linux-api-owner@vger.kernel.org X-Mailing-List: linux-api@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Ingo, Peter, Thomas, Here is the updated membarrier patch series following review from Thomas. It would be appreciated of those can go through the scheduler tree for the 4.16 merge window. Highlights: "powerpc: membarrier: Skip memory barrier in switch_mm()" takes care of a TODO that was left in the private expedited implementation when merged in 4.14: an extra memory barrier was added on context switch on powerpc. Ensure that the barrier is only performed when scheduling between different processes, only for threads belonging to processes that have registered their intent to use the private expedited command. "membarrier: provide GLOBAL_EXPEDITED command" adds new commands to membarrier for registration and use of membarrier across processes communicating through shared memory mappings. The non-expedited command has proven to be really too slow (taking 10ms and more to complete) for real-world use. The expedited version completes in a matter of microseconds. This patch renames the pre-existing MEMBARRIER_CMD_SHARED to MEMBARRIER_CMD_GLOBAL for consistency, keeping the old enum label as an alias for backward compatibility. "membarrier: Provide core serializing command" provides core serialization for JIT reclaim. We received positive feedback from Android developers that the proposed ABI fits their use-case. Only x86 32/64 and arm 64 implement this command so far. This is opt-in per architecture. The other patches add selftests and documentation. Thanks, Mathieu Mathieu Desnoyers (11): membarrier: selftest: Test private expedited cmd (v2) powerpc: membarrier: Skip memory barrier in switch_mm() (v7) membarrier: Document scheduler barrier requirements (v5) membarrier: provide GLOBAL_EXPEDITED command (v3) membarrier: selftest: Test global expedited cmd (v2) Introduce sync_core_before_usermode x86: Implement sync_core_before_usermode (v3) membarrier: Provide core serializing command membarrier: x86: Provide core serializing command (v4) membarrier: arm64: Provide core serializing command membarrier: selftest: Test private expedited sync core cmd MAINTAINERS | 1 + arch/arm64/Kconfig | 1 + arch/arm64/kernel/entry.S | 4 + arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/membarrier.h | 27 +++ arch/powerpc/mm/mmu_context.c | 7 + arch/x86/Kconfig | 2 + arch/x86/entry/entry_32.S | 5 + arch/x86/entry/entry_64.S | 4 + arch/x86/include/asm/processor.h | 10 + arch/x86/mm/tlb.c | 6 + include/linux/processor.h | 6 + include/linux/sched/mm.h | 40 +++- include/uapi/linux/membarrier.h | 74 ++++++- init/Kconfig | 9 + kernel/sched/core.c | 53 +++-- kernel/sched/membarrier.c | 177 +++++++++++++-- .../testing/selftests/membarrier/membarrier_test.c | 237 +++++++++++++++++++-- 18 files changed, 596 insertions(+), 68 deletions(-) create mode 100644 arch/powerpc/include/asm/membarrier.h -- 2.11.0