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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 A8C21C43387 for ; Wed, 9 Jan 2019 17:26:33 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 79364214C6 for ; Wed, 9 Jan 2019 17:26:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="G+YhuKmh" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 79364214C6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-mips.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject: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=uIGokAJJhrK9QWkDVY7ItyRxaaFDFbizYI6dv44HqOE=; b=G+YhuKmhEWN4Vm H7qc0eYBkefwrOU6iqqIfLzja6mKfqRxAVsmbOovl+YPNgq7AWIk1M/Sfox0GXlomNv7bodsmpwcH D75KwQf2ZNEMnBms2RdSrfn8t+k7LcZzVOLEkdSn0PEjFCMIz9VXCtb1AIRKJ3oF9xwDzLyf0RPXC vY5F7UTDj3PtEpyNJXofcSq7sDpAbY50xl9lAKnjZKb4m3GFA0P4DbjOzv9PzrwecJl9oTMVRDjja uKg9ASPbQkZPaOLeyuSt2ezaKyhcc7XVJqxQUAdiecuF7cOpw1WWkHsig37Q/e/ON5XNrLHGRpOWx 302S3yI1IOn1bP2ZA19g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1ghHcc-00022e-D5; Wed, 09 Jan 2019 17:26:30 +0000 Received: from eddie.linux-mips.org ([148.251.95.138] helo=cvs.linux-mips.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1ghHcY-00021t-M2 for linux-arm-kernel@lists.infradead.org; Wed, 09 Jan 2019 17:26:28 +0000 Received: (from localhost user: 'ladis' uid#1021 fake: STDIN (ladis@eddie.linux-mips.org)) by eddie.linux-mips.org id S23993997AbfAIR0YHuWuZ (ORCPT ); Wed, 9 Jan 2019 18:26:24 +0100 Date: Wed, 9 Jan 2019 18:26:23 +0100 From: Ladislav Michl To: Vincent Guittot Subject: Re: Regression in v5.0-rc1 with autosuspend hrtimers Message-ID: <20190109172623.GB1711@lenoch> References: <20190108213743.GN5544@atomide.com> <20190109014218.GA8363@linaro.org> <20190109111703.GA28605@lenoch> <20190109115824.GA1353@lenoch> <20190109133337.GA13579@lenoch> <20190109160736.GA7416@lenoch> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190109_092626_718939_50B67BE5 X-CRM114-Status: GOOD ( 22.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ulf Hansson , "open list:THERMAL" , Tony Lindgren , "Rafael J. Wysocki" , linux-kernel , linux-omap@vger.kernel.org, LAK Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 09, 2019 at 05:32:31PM +0100, Vincent Guittot wrote: > On Wed, 9 Jan 2019 at 17:07, Ladislav Michl wrote: > > > > On Wed, Jan 09, 2019 at 03:12:25PM +0100, Vincent Guittot wrote: > > > Please keep all thread list when replying :-) > > > > Ahh, sorry for that... > > [snip] > > > On Wed, 9 Jan 2019 at 14:33, Ladislav Michl wrote: > > > > I agree, but it doea all the magic correctly, so you won't need > > > > to touch that code is ktime_t changes (I know, unlikely..) > > > > > > But the current implementation doesn't care of any changes in ktime_t > > > as it uses raw ns > > > > Fair enough, so let's go back to: > > This one looks good for me Lets split is for 'comments fix' patch, which was just send and 'the rest'. Now, 'the rest' can either be v2 of your "PM/runtime: Fix autosuspend_delay on 32bits arch" or will wait for 5.1. You decide :) > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > > index 70624695b6d5..e61ee9b47a26 100644 > > --- a/drivers/base/power/runtime.c > > +++ b/drivers/base/power/runtime.c > > @@ -121,7 +121,7 @@ static void pm_runtime_cancel_pending(struct device *dev) > > * Compute the autosuspend-delay expiration time based on the device's > > * power.last_busy time. If the delay has already expired or is disabled > > * (negative) or the power.use_autosuspend flag isn't set, return 0. > > - * Otherwise return the expiration time in jiffies (adjusted to be nonzero). > > + * Otherwise return the expiration time in nanoseconds (adjusted to be nonzero). > > * > > * This function may be called either with or without dev->power.lock held. > > * Either way it can be racy, since power.last_busy may be updated at any time. > > @@ -129,24 +129,21 @@ static void pm_runtime_cancel_pending(struct device *dev) > > u64 pm_runtime_autosuspend_expiration(struct device *dev) > > { > > int autosuspend_delay; > > - u64 last_busy, expires = 0; > > - u64 now = ktime_to_ns(ktime_get()); > > + u64 expires; > > > > if (!dev->power.use_autosuspend) > > - goto out; > > + return 0; > > > > autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); > > if (autosuspend_delay < 0) > > - goto out; > > - > > - last_busy = READ_ONCE(dev->power.last_busy); > > + return 0; > > > > - expires = last_busy + autosuspend_delay * NSEC_PER_MSEC; > > - if (expires <= now) > > - expires = 0; /* Already expired. */ > > + expires = READ_ONCE(dev->power.last_busy); > > + expires += NSEC_PER_MSEC * (u64)autosuspend_delay; > > + if (expires > ktime_to_ns(ktime_get())) > > + return expires; /* Expires in the future */ > > > > - out: > > - return expires; > > + return 0; > > } > > EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); > > > > Which gives for arm: > > 00000480 : > > 480: e92d41f0 push {r4, r5, r6, r7, r8, lr} > > 484: e5d030d1 ldrb r3, [r0, #209] ; 0xd1 > > 488: e3130004 tst r3, #4 > > 48c: 0a00000c beq 4c4 > > 490: e59030e4 ldr r3, [r0, #228] ; 0xe4 > > 494: e3530000 cmp r3, #0 > > 498: ba000009 blt 4c4 > > 49c: e28050e8 add r5, r0, #232 ; 0xe8 > > 4a0: e8950030 ldm r5, {r4, r5} > > 4a4: e59f2030 ldr r2, [pc, #48] ; 4dc > > 4a8: e0e54392 smlal r4, r5, r2, r3 > > 4ac: ebfffffe bl 0 > > 4b0: e1550001 cmp r5, r1 > > 4b4: 01540000 cmpeq r4, r0 > > 4b8: e1a06004 mov r6, r4 > > 4bc: e1a07005 mov r7, r5 > > 4c0: 8a000001 bhi 4cc > > 4c4: e3a06000 mov r6, #0 > > 4c8: e3a07000 mov r7, #0 > > 4cc: e1a00006 mov r0, r6 > > 4d0: e1a01007 mov r1, r7 > > 4d4: e8bd41f0 pop {r4, r5, r6, r7, r8, lr} > > 4d8: e12fff1e bx lr > > 4dc: 000f4240 .word 0x000f4240 > > > > And x86: > > 0000000000000230 : > > 230: 8b 87 a4 01 00 00 mov 0x1a4(%rdi),%eax > > 236: 53 push %rbx > > 237: 85 c0 test %eax,%eax > > 239: 78 1e js 259 > > 23b: 48 63 d8 movslq %eax,%rbx > > 23e: 48 8b 97 a8 01 00 00 mov 0x1a8(%rdi),%rdx > > 245: 48 69 db 40 42 0f 00 imul $0xf4240,%rbx,%rbx > > 24c: 48 01 d3 add %rdx,%rbx > > 24f: e8 00 00 00 00 callq 254 > > 254: 48 39 c3 cmp %rax,%rbx > > 257: 77 02 ja 25b > > 259: 31 db xor %ebx,%ebx > > 25b: 48 89 d8 mov %rbx,%rax > > 25e: 5b pop %rbx > > 25f: c3 retq > > > > 00000000000002a0 : > > 2a0: f6 87 91 01 00 00 04 testb $0x4,0x191(%rdi) > > 2a7: 74 02 je 2ab > > 2a9: eb 85 jmp 230 > > 2ab: 31 c0 xor %eax,%eax > > 2ad: c3 retq > > 2ae: 66 90 xchg %ax,%ax > > > > > > [snip] > > > > Well, main concern was not to call ktime_get at the beginning of function > > > > as it is not too cheap. > > > > > > Doesn't the compiler optimize that to just before the test ? > > > > No (compare with above). And it is also almost certain that someone will run > > script and send "...do not needlesly initialize..." patch :) > > > > gcc version 8.2.1 20181130 (OSELAS.Toolchain-2018.12.0 8-20181130) > > > > 00000110 : > > 110: e92d41f0 push {r4, r5, r6, r7, r8, lr} > > 114: e1a06000 mov r6, r0 > > 118: ebfffffe bl 0 > > 11c: e5d630d1 ldrb r3, [r6, #209] ; 0xd1 > > 120: e3130004 tst r3, #4 > > 124: 0a00000d beq 160 > > 128: e596c0e4 ldr ip, [r6, #228] ; 0xe4 > > 12c: e35c0000 cmp ip, #0 > > 130: ba00000a blt 160 > > 134: e28630e8 add r3, r6, #232 ; 0xe8 > > 138: e893000c ldm r3, {r2, r3} > > 13c: e1a05001 mov r5, r1 > > 140: e1a04000 mov r4, r0 > > 144: e59f002c ldr r0, [pc, #44] ; 178 > > 148: e0010c90 mul r1, r0, ip > > 14c: e0926001 adds r6, r2, r1 > > 150: e0a37fc1 adc r7, r3, r1, asr #31 > > 154: e1550007 cmp r5, r7 > > 158: 01540006 cmpeq r4, r6 > > 15c: 3a000001 bcc 168 > > 160: e3a06000 mov r6, #0 > > 164: e3a07000 mov r7, #0 > > 168: e1a00006 mov r0, r6 > > 16c: e1a01007 mov r1, r7 > > 170: e8bd41f0 pop {r4, r5, r6, r7, r8, lr} > > 174: e12fff1e bx lr > > 178: 000f4240 .word 0x000f4240 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel