From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0BE9C433E7 for ; Wed, 14 Oct 2020 08:34:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 927ED20BED for ; Wed, 14 Oct 2020 08:34:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="waB2eQIr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729448AbgJNIeL (ORCPT ); Wed, 14 Oct 2020 04:34:11 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:37972 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729365AbgJNIeL (ORCPT ); Wed, 14 Oct 2020 04:34:11 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09E8Ua63182186; Wed, 14 Oct 2020 08:33:43 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=corp-2020-01-29; bh=RJVK+CzUyTBfDw8obQvm5ubHP60lgkWKdRwFkICT7nw=; b=waB2eQIrwmiMTY3v0fBxN+93kgkczxJ4quJYyja93bd6i5Dm8tsjGIB7W2Js086WpoVB 4enKt3KAE78OZNY+6kIBzbWDQ3YC20h4JXcNjE5i9/HzvUMLKMsCdhblh/AnGtei7iix Vo+T+hmgGh73p7YHMb7LlNntZJxaaQNLIBr7reXMxvpbUffuCKjZtDt+VrGr3jtMM8aJ e/FqGOoZ0S6J+nW4W2DRpzaL4m/I05aHv9uAZODqoLDYnBVmLgNMHRnCc0ELj4kBOrfI TSVIU5vxg3KXD2eTH1VmHEpGbb5iwDjT/ksM0rdp8AlrvS5/pIM+9zqTU87kKTLHpzZ7 jA== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2120.oracle.com with ESMTP id 3434wkp60x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 14 Oct 2020 08:33:43 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09E8TYC9005668; Wed, 14 Oct 2020 08:33:42 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userp3020.oracle.com with ESMTP id 344by3a4y5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 14 Oct 2020 08:33:42 +0000 Received: from abhmp0014.oracle.com (abhmp0014.oracle.com [141.146.116.20]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 09E8XeAc021661; Wed, 14 Oct 2020 08:33:40 GMT Received: from monad.ca.oracle.com (/10.156.74.184) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 14 Oct 2020 01:33:40 -0700 From: Ankur Arora To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: kirill@shutemov.name, mhocko@kernel.org, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, Ankur Arora , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Tony Luck , Sean Christopherson , Mike Rapoport , Xiaoyao Li , Fenghua Yu , "Peter Zijlstra (Intel)" , Dave Hansen Subject: [PATCH 7/8] x86/cpu/intel: enable X86_FEATURE_NT_GOOD on Intel Broadwellx Date: Wed, 14 Oct 2020 01:32:58 -0700 Message-Id: <20201014083300.19077-8-ankur.a.arora@oracle.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201014083300.19077-1-ankur.a.arora@oracle.com> References: <20201014083300.19077-1-ankur.a.arora@oracle.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9773 signatures=668681 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 spamscore=0 suspectscore=0 mlxscore=0 malwarescore=0 adultscore=0 bulkscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010140061 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9773 signatures=668681 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 mlxscore=0 malwarescore=0 phishscore=0 suspectscore=0 impostorscore=0 clxscore=1011 spamscore=0 priorityscore=1501 bulkscore=0 adultscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010140061 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org System: Oracle X6-2 CPU: 2 nodes * 10 cores/node * 2 threads/core Intel Xeon E5-2630 v4 (Broadwellx, 6:79:1) Memory: 256 GB evenly split between nodes Microcode: 0xb00002e scaling_governor: performance L3 size: 25MB intel_pstate/no_turbo: 1 Performance comparison of 'perf bench mem memset -l 1' for x86-64-stosb (X86_FEATURE_ERMS) and x86-64-movnt (X86_FEATURE_NT_GOOD): x86-64-stosb (5 runs) x86-64-movnt (5 runs) speedup ----------------------- ----------------------- ------- size BW ( pstdev) BW ( pstdev) 16MB 17.35 GB/s ( +- 9.27%) 11.83 GB/s ( +- 0.19%) -31.81% 128MB 5.31 GB/s ( +- 0.13%) 11.72 GB/s ( +- 0.44%) +121.84% 1024MB 5.42 GB/s ( +- 0.13%) 11.78 GB/s ( +- 0.03%) +117.34% 4096MB 5.41 GB/s ( +- 0.41%) 11.76 GB/s ( +- 0.07%) +117.37% The next workload exercises the page-clearing path directly by faulting over an anonymous mmap region backed by 1GB pages. This workload is similar to the creation phase of pinned guests in QEMU. $ cat pf-test.c #include #include #include #define HPAGE_BITS 30 int main(int argc, char **argv) { int i; unsigned long len = atoi(argv[1]); /* In GB */ unsigned long offset = 0; unsigned long numpages; char *base; len *= 1UL << 30; numpages = len >> HPAGE_BITS; base = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_HUGE_1GB, 0, 0); for (i = 0; i < numpages; i++) { *((volatile char *)base + offset) = *(base + offset); offset += 1UL << HPAGE_BITS; } return 0; } The specific test is for a 128GB region but this is a single-threaded O(n) workload so the exact region size is not material. Page-clearing throughput for clear_page_erms(): 3.72 GBps $ perf stat -r 5 --all-kernel -e ... bin/pf-test 128 Performance counter stats for 'bin/pf-test 128' (5 runs): 74,799,496,556 cpu-cycles # 2.176 GHz ( +- 2.22% ) (29.41%) 1,474,615,023 instructions # 0.02 insn per cycle ( +- 0.23% ) (35.29%) 2,148,580,131 cache-references # 62.502 M/sec ( +- 0.02% ) (35.29%) 71,736,985 cache-misses # 3.339 % of all cache refs ( +- 0.94% ) (35.29%) 433,713,165 branch-instructions # 12.617 M/sec ( +- 0.15% ) (35.30%) 1,008,251 branch-misses # 0.23% of all branches ( +- 1.88% ) (35.30%) 3,406,821,966 bus-cycles # 99.104 M/sec ( +- 2.22% ) (23.53%) 2,156,059,110 L1-dcache-load-misses # 445.35% of all L1-dcache accesses ( +- 0.01% ) (23.53%) 484,128,243 L1-dcache-loads # 14.083 M/sec ( +- 0.22% ) (23.53%) 944,216 LLC-loads # 0.027 M/sec ( +- 7.41% ) (23.53%) 537,989 LLC-load-misses # 56.98% of all LL-cache accesses ( +- 13.64% ) (23.53%) 2,150,138,476 LLC-stores # 62.547 M/sec ( +- 0.01% ) (11.76%) 69,598,760 LLC-store-misses # 2.025 M/sec ( +- 0.47% ) (11.76%) 483,923,875 dTLB-loads # 14.077 M/sec ( +- 0.21% ) (17.64%) 1,892 dTLB-load-misses # 0.00% of all dTLB cache accesses ( +- 30.63% ) (23.53%) 4,799,154,980 dTLB-stores # 139.606 M/sec ( +- 0.03% ) (23.53%) 90 dTLB-store-misses # 0.003 K/sec ( +- 35.92% ) (23.53%) 34.377 +- 0.760 seconds time elapsed ( +- 2.21% ) Page-clearing throughput with clear_page_nt(): 11.78GBps $ perf stat -r 5 --all-kernel -e ... bin/pf-test 128 Performance counter stats for 'bin/pf-test 128' (5 runs): 23,699,446,603 cpu-cycles # 2.182 GHz ( +- 0.01% ) (23.53%) 24,794,548,512 instructions # 1.05 insn per cycle ( +- 0.00% ) (29.41%) 432,775 cache-references # 0.040 M/sec ( +- 3.96% ) (29.41%) 75,580 cache-misses # 17.464 % of all cache refs ( +- 51.42% ) (29.41%) 2,492,858,290 branch-instructions # 229.475 M/sec ( +- 0.00% ) (29.42%) 34,016,826 branch-misses # 1.36% of all branches ( +- 0.04% ) (29.42%) 1,078,468,643 bus-cycles # 99.276 M/sec ( +- 0.01% ) (23.53%) 717,228 L1-dcache-load-misses # 0.20% of all L1-dcache accesses ( +- 3.77% ) (23.53%) 351,999,535 L1-dcache-loads # 32.403 M/sec ( +- 0.04% ) (23.53%) 75,988 LLC-loads # 0.007 M/sec ( +- 4.20% ) (23.53%) 24,503 LLC-load-misses # 32.25% of all LL-cache accesses ( +- 53.30% ) (23.53%) 57,283 LLC-stores # 0.005 M/sec ( +- 2.15% ) (11.76%) 19,738 LLC-store-misses # 0.002 M/sec ( +- 46.55% ) (11.76%) 351,836,498 dTLB-loads # 32.388 M/sec ( +- 0.04% ) (17.65%) 1,171 dTLB-load-misses # 0.00% of all dTLB cache accesses ( +- 42.68% ) (23.53%) 17,385,579,725 dTLB-stores # 1600.392 M/sec ( +- 0.00% ) (23.53%) 200 dTLB-store-misses # 0.018 K/sec ( +- 10.63% ) (23.53%) 10.863678 +- 0.000804 seconds time elapsed ( +- 0.01% ) L1-dcache-load-misses (L1D.REPLACEMENT) is substantially lower which suggests that, as expected, we aren't doing write-allocate or RFO. Note that the IPC and instruction counts etc are quite different, but that's just an artifact of switching from a single 'REP; STOSB' per PAGE_SIZE region to a MOVNTI loop. The page-clearing BW is substantially higher (~100% or more), so enable X86_FEATURE_NT_GOOD for Intel Broadwellx. Signed-off-by: Ankur Arora --- arch/x86/kernel/cpu/intel.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 59a1e3ce3f14..161028c1dee0 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -662,6 +662,8 @@ static void init_intel(struct cpuinfo_x86 *c) c->x86_cache_alignment = c->x86_clflush_size * 2; if (c->x86 == 6) set_cpu_cap(c, X86_FEATURE_REP_GOOD); + if (c->x86 == 6 && c->x86_model == INTEL_FAM6_BROADWELL_X) + set_cpu_cap(c, X86_FEATURE_NT_GOOD); #else /* * Names for the Pentium II/Celeron processors -- 2.9.3