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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 24A8DC433EF for ; Mon, 11 Apr 2022 09:35:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Vvk15pt4gVjvvoWcRPqw9loQRfhGqs9Umk6D33FFnM4=; b=3LrvKiOn+TbW7X A799PHtIAh+RtrX829YmJPbBmeBEHIP4sG1lBF3ePZjuT+TTAwIAfP8+T4BZZy6oQ+tAzzvSPKcVT LutcL8yviTzjRYkuAg7tSAaph35/Vyd77li82ed/qhuGLJb8TnzubLfFf/u8QVuYcMZifYEQjI+Gb QD1GMJ2mLrvHQ5KiH270JYNskl9PUoYVrbzEJT3YVHYcZm/iVXtuTri82s/mjwP4ZiG5kJHhAjGbR Eoj2lxqPMUb9jLI5+LweG0HIDmAW/nOS3AvexZpdpldg8ZIEwDJSyvkhAeyMuFya80oPBHRywG6Y6 7rBMhlQ9nJWy/I5akUKQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ndqS0-007xE6-EE; Mon, 11 Apr 2022 09:35:12 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ndqRw-007xCN-QO for linux-riscv@lists.infradead.org; Mon, 11 Apr 2022 09:35:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 083BEED1; Mon, 11 Apr 2022 02:35:02 -0700 (PDT) Received: from FVFF77S0Q05N (unknown [10.57.9.30]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A11483F793; Mon, 11 Apr 2022 02:35:00 -0700 (PDT) Date: Mon, 11 Apr 2022 10:34:52 +0100 From: Mark Rutland To: guoren@kernel.org Cc: palmer@rivosinc.com, arnd@arndb.de, peterz@infradead.org, linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Guo Ren , Palmer Dabbelt Subject: Re: [PATCH] riscv: Optimize AMO acquire/release usage Message-ID: References: <20220406120405.660354-1-guoren@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220406120405.660354-1-guoren@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220411_023509_005844_6B0BA980 X-CRM114-Status: GOOD ( 13.64 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org SGkgR3VvLAoKT24gV2VkLCBBcHIgMDYsIDIwMjIgYXQgMDg6MDQ6MDVQTSArMDgwMCwgZ3VvcmVu QGtlcm5lbC5vcmcgd3JvdGU6Cj4gRnJvbTogR3VvIFJlbiA8Z3VvcmVuQGxpbnV4LmFsaWJhYmEu Y29tPgo+IAo+IFVzaW5nIFJJU0NWX0FDUVVJUkUvUkVMRUFTRV9CQVJSSUVSIGlzIG92ZXIgZXhw ZW5zaXZlIGZvcgo+IHhjaGcvY21weGNoZ19hY3F1aXJlL3JlbGVhc2UgdGhhbiBuYXR1cmUgaW5z dHJ1Y3Rpb25zJyAuYXEvcmwuCj4gVGhlIHBhdGNoIGZpeGVkIHRoZXNlIGlzc3VlcyB1bmRlciBS SVNDLVYgSW5zdHJ1Y3Rpb24gU2V0IE1hbnVhbCwKPiBWb2x1bWUgSTogUklTQy1WIFVzZXItTGV2 ZWwgSVNBIOKAnEHigJ0gU3RhbmRhcmQgRXh0ZW5zaW9uIGZvciBBdG9taWMKPiBJbnN0cnVjdGlv bnMsIFZlcnNpb24gMi4xLgo+IAo+IFNpZ25lZC1vZmYtYnk6IEd1byBSZW4gPGd1b3JlbkBsaW51 eC5hbGliYWJhLmNvbT4KPiBTaWduZWQtb2ZmLWJ5OiBHdW8gUmVuIDxndW9yZW5Aa2VybmVsLm9y Zz4KPiBDYzogUGFsbWVyIERhYmJlbHQgPHBhbG1lckBkYWJiZWx0LmNvbT4KPiAtLS0KPiAgYXJj aC9yaXNjdi9pbmNsdWRlL2FzbS9hdG9taWMuaCAgfCA3MCArKysrKysrKysrKysrKysrKysrKysr KysrKysrKystLQo+ICBhcmNoL3Jpc2N2L2luY2x1ZGUvYXNtL2NtcHhjaGcuaCB8IDMwICsrKysr LS0tLS0tLS0tCj4gIDIgZmlsZXMgY2hhbmdlZCwgNzYgaW5zZXJ0aW9ucygrKSwgMjQgZGVsZXRp b25zKC0pCgpJJ2xsIGxlYXZlIHRoZSBidWxrIG9mIHRoaXMgdG8gUGFsbWVyLCBidXQgSSBzcG90 dGVkIHNvbWV0aGluZyBiZWxvdyB3aGljaApkb2Vzbid0IGxvb2sgcmlnaHQuCgo+IEBAIC0zMTUs MTIgKzM3OSwxMSBAQCBzdGF0aWMgX19hbHdheXNfaW5saW5lIGludCBhcmNoX2F0b21pY19zdWJf aWZfcG9zaXRpdmUoYXRvbWljX3QgKnYsIGludCBvZmZzZXQpCj4gICAgICAgICBpbnQgcHJldiwg cmM7Cj4gIAo+ICAJX19hc21fXyBfX3ZvbGF0aWxlX18gKAo+IC0JCSIwOglsci53ICAgICAlW3Bd LCAgJVtjXVxuIgo+ICsJCSIwOglsci53LmFxICAlW3BdLCAgJVtjXVxuIgo+ICAJCSIJc3ViICAg ICAgJVtyY10sICVbcF0sICVbb11cbiIKPiAgCQkiCWJsdHogICAgICVbcmNdLCAxZlxuIgo+ICAJ CSIJc2Mudy5ybCAgJVtyY10sICVbcmNdLCAlW2NdXG4iCj4gIAkJIglibmV6ICAgICAlW3JjXSwg MGJcbiIKPiAtCQkiCWZlbmNlICAgIHJ3LCByd1xuIgo+ICAJCSIxOlxuIgo+ICAJCTogW3BdIj0m ciIgKHByZXYpLCBbcmNdIj0mciIgKHJjKSwgW2NdIitBIiAodi0+Y291bnRlcikKPiAgCQk6IFtv XSJyIiAob2Zmc2V0KQoKSSBiZWxpZXZlIGluIHRoaXMgY2FzZSB0aGUgZXhpc3RpbmcgY29kZSBo ZXJlIGlzIGNvcnJlY3QsIGFuZCB0aGlzIG9wdGltaXphdGlvbgppcyBicm9rZW4uCgpJIGJlbGll dmUgdGhlIGV4aXN0aW5nIGNvZGUgaXMgdXNpbmcgUkVMRUFTRSArIEZVTEwtQkFSUklFUiB0byBl bnN1cmUgZnVsbApvcmRlcmluZywgc2luY2Ugc2VwYXJhdGUgQUNRVUlSRStSRUxFQVNFIGNhbm5v dC4gRm9yIGEgZGVzY3JpcHRpb24gb2YgdGhlCnByb2JsZW0sIHNlZSB0aGUgY29tbWl0IG1lc3Nh Z2UgZm9yOgoKICA4ZTg2ZjBiNDA5YTQ0MTkzICgiYXJtNjQ6IGF0b21pY3M6IGZpeCB1c2Ugb2Yg YWNxdWlyZSArIHJlbGVhc2UgZm9yIGZ1bGwgYmFycmllciBzZW1hbnRpY3MiKQoKVGhlIGdpc3Qg aXMgdGhhdCBIVyBjYW4gcmUtb3JkZXI6CgoJQUNDRVNTLUEKCUFDUVVJUkUKCVJFTEVBU0UKCUFD Q0VTUy1CCgouLi4gdG86CgoJQUNRVUlSRQoJQUNDRVNTLUIKCUFDQ0VTUy1BCglSRUxFQVNFCgou Li4gdmlvbGF0aW5nIEZVTEwgb3JkZXJpbmcgc2VtYW50aWNzLgoKVGhpcyB3aWxsIGFwcGx5IGZv ciAqYW55KiBvcGVyYXRpb24gd2hlcmUgRlVMTCBvcmRlcmluZ2lzIHJlcXVpcmVkLCB3aGljaCBJ CnN1c3BlY3QgYXBwbGllcyB0byBzb21lIG1vcmUgY2FzZXMgYmVsb3cuCgo+IEBAIC0zMzcsMTIg KzQwMCwxMSBAQCBzdGF0aWMgX19hbHdheXNfaW5saW5lIHM2NCBhcmNoX2F0b21pYzY0X3N1Yl9p Zl9wb3NpdGl2ZShhdG9taWM2NF90ICp2LCBzNjQgb2Zmcwo+ICAgICAgICAgbG9uZyByYzsKPiAg Cj4gIAlfX2FzbV9fIF9fdm9sYXRpbGVfXyAoCj4gLQkJIjA6CWxyLmQgICAgICVbcF0sICAlW2Nd XG4iCj4gKwkJIjA6CWxyLmQuYXEgICVbcF0sICAlW2NdXG4iCj4gIAkJIglzdWIgICAgICAlW3Jj XSwgJVtwXSwgJVtvXVxuIgo+ICAJCSIJYmx0eiAgICAgJVtyY10sIDFmXG4iCj4gIAkJIglzYy5k LnJsICAlW3JjXSwgJVtyY10sICVbY11cbiIKPiAgCQkiCWJuZXogICAgICVbcmNdLCAwYlxuIgo+ IC0JCSIJZmVuY2UgICAgcncsIHJ3XG4iCj4gIAkJIjE6XG4iCj4gIAkJOiBbcF0iPSZyIiAocHJl diksIFtyY10iPSZyIiAocmMpLCBbY10iK0EiICh2LT5jb3VudGVyKQo+ICAJCTogW29dInIiIChv ZmZzZXQpCgpNeSBjb21tZW50IGZvciBhcmNoX2F0b21pY19zdWJfaWZfcG9zaXRpdmUoKSBhcHBs aWVzIGhlcmUgdG9vLgoKClsuLi5dCgo+IEBAIC0zMDksMTEgKzMwMSwxMCBAQAo+ICAJc3dpdGNo IChzaXplKSB7CQkJCQkJCVwKPiAgCWNhc2UgNDoJCQkJCQkJCVwKPiAgCQlfX2FzbV9fIF9fdm9s YXRpbGVfXyAoCQkJCQlcCj4gLQkJCSIwOglsci53ICUwLCAlMlxuIgkJCQlcCj4gKwkJCSIwOgls ci53LmFxICUwLCAlMlxuIgkJCVwKPiAgCQkJIglibmUgICUwLCAlejMsIDFmXG4iCQkJXAo+ICAJ CQkiCXNjLncucmwgJTEsICV6NCwgJTJcbiIJCQlcCj4gIAkJCSIJYm5leiAlMSwgMGJcbiIJCQkJ XAo+IC0JCQkiCWZlbmNlIHJ3LCByd1xuIgkJCQlcCj4gIAkJCSIxOlxuIgkJCQkJCVwKPiAgCQkJ OiAiPSZyIiAoX19yZXQpLCAiPSZyIiAoX19yYyksICIrQSIgKCpfX3B0cikJXAo+ICAJCQk6ICJy SiIgKChsb25nKV9fb2xkKSwgInJKIiAoX19uZXcpCQlcCj4gQEAgLTMyMSwxMSArMzEyLDEwIEBA Cj4gIAkJYnJlYWs7CQkJCQkJCVwKPiAgCWNhc2UgODoJCQkJCQkJCVwKPiAgCQlfX2FzbV9fIF9f dm9sYXRpbGVfXyAoCQkJCQlcCj4gLQkJCSIwOglsci5kICUwLCAlMlxuIgkJCQlcCj4gKwkJCSIw Oglsci5kLmFxICUwLCAlMlxuIgkJCVwKPiAgCQkJIglibmUgJTAsICV6MywgMWZcbiIJCQlcCj4g IAkJCSIJc2MuZC5ybCAlMSwgJXo0LCAlMlxuIgkJCVwKPiAgCQkJIglibmV6ICUxLCAwYlxuIgkJ CQlcCj4gLQkJCSIJZmVuY2UgcncsIHJ3XG4iCQkJCVwKPiAgCQkJIjE6XG4iCQkJCQkJXAo+ICAJ CQk6ICI9JnIiIChfX3JldCksICI9JnIiIChfX3JjKSwgIitBIiAoKl9fcHRyKQlcCj4gIAkJCTog InJKIiAoX19vbGQpLCAickoiIChfX25ldykJCQlcCgpJIGRvbid0IGhhdmUgZW5vdWdoIGNvbnRl eHQgdG8gc2F5IGZvciBzdXJlLCBidXQgSSBzdXNwZWN0IHRoZXNlIGFyZSBleHBlY3RpbmcKRlVM TCBvcmRlcmluZyB0b28sIGFuZCB3b3VsZCBiZSBicm9rZW4sIGFzIGFib3ZlLgoKVGhhbmtzLApN YXJrLgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGlu dXgtcmlzY3YgbWFpbGluZyBsaXN0CmxpbnV4LXJpc2N2QGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0 cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1yaXNjdgo=