From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-04.galae.net (smtpout-04.galae.net [185.171.202.116]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A1B42309EEC; Thu, 29 Jan 2026 16:05:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.171.202.116 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769702737; cv=none; b=kbcF+jeSAPRpMX7RlJxk+g7uMungB7/aWcfLes4r8Or8ODiPPJGngEB7SIoLI0DwiPlbtZI/c/GgRFSVcgJYpFiG3JPqrIItoA4Eq78bQ3fAx0utHxxUG5iGsEwW7Nm0w6smDyAN7Qhrh/FDbEy6j09Jr/47Qz9Gf75Opk3VhhY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769702737; c=relaxed/simple; bh=yVdibtwtGBdtM6zRoTTns3ysNbJg04ECgBNHy8kebSA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JnuZXbnQdypQAsgof/qMSu+GZroigSeF9UgDgd3PT530+tTO8wJ31f+YwW/Mgi37thJCJ4fREWpZa0lkqka0Xn6dEDC0R9JoGmUqh5qmFYR+kMeRyyVuuLghYDXWHtR0+bv0CG7e6lX343R+Id/mkf4aAMqaLOQWwH9gSPS7KVU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=mNSQY84L; arc=none smtp.client-ip=185.171.202.116 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="mNSQY84L" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id 5E81CC22F46; Thu, 29 Jan 2026 16:05:35 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 4FCDF60746; Thu, 29 Jan 2026 16:05:32 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id C84C6119A8095; Thu, 29 Jan 2026 17:05:27 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1769702731; h=from:subject:date:message-id:to:cc:mime-version:content-type: in-reply-to:references; bh=Lc6wWk4IgTT559wWGEQNQjCDMW6utgy5FoBxVvSG2KM=; b=mNSQY84LQ52ZnscGD18IByJvZJQQIacVebk2t/plG/whMwn+83Zl1E9OvoWX2V2RxCfoxS J7FKlupj1VB7e6rJFirr6RfK/Oy8A6bsRNzcw474UsjN/FbndmiovBhMgwm4YRKoBwKFmx 3ZeTXY3A03ZQLaJOCIiO8R9mHEDa7oyn4WPEqgrGwV6YrglWUK6/soN5WeE49FI13rIEZA q4eMBtWPKykfEWe2ps7aGWr4/JW4mG1Uq3VhlwwNdXdiVcqnGgeBHoWH5R9jClm0TjLX7V OKWIWCnc7iGZ2Eb/+sESPRrxzaJ8ZnvdKXHvmTHen/Ais5igGxDQBGU8jw1rrw== Date: Thu, 29 Jan 2026 17:05:27 +0100 From: Alexandre Belloni To: rouven.czerwinski@linaro.org Cc: Jens Wiklander , Sumit Garg , Olivia Mackall , Herbert Xu , =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , op-tee@lists.trustedfirmware.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-rtc@vger.kernel.org Subject: Re: [PATCH 3/3] rtc: optee: simplify OP-TEE context match Message-ID: <202601291605277bc279f4@mail.local> References: <20260126-optee-simplify-context-match-v1-0-d4104e526cb6@linaro.org> <20260126-optee-simplify-context-match-v1-3-d4104e526cb6@linaro.org> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260126-optee-simplify-context-match-v1-3-d4104e526cb6@linaro.org> X-Last-TLS-Session-Version: TLSv1.3 On 26/01/2026 11:11:26+0100, Rouven Czerwinski via B4 Relay wrote: > From: Rouven Czerwinski > > Simplify the TEE implementor ID match by returning the boolean > expression directly instead of going through an if/else. > > Signed-off-by: Rouven Czerwinski > --- > drivers/rtc/rtc-optee.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c > index 184c6d142801..2f18be3de684 100644 > --- a/drivers/rtc/rtc-optee.c > +++ b/drivers/rtc/rtc-optee.c > @@ -541,10 +541,7 @@ static int optee_rtc_read_info(struct device *dev, struct rtc_device *rtc, > > static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) > { > - if (ver->impl_id == TEE_IMPL_ID_OPTEE) > - return 1; > - else > - return 0; > + return (ver->impl_id == TEE_IMPL_ID_OPTEE); I guess the correct way to do this would be: return !!(ver->impl_id == TEE_IMPL_ID_OPTEE); But is this change actually generating better code? Before: static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) { if (ver->impl_id == TEE_IMPL_ID_OPTEE) 0: e5900000 ldr r0, [r0] return 1; else return 0; } 4: e2400001 sub r0, r0, #1 8: e16f0f10 clz r0, r0 c: e1a002a0 lsr r0, r0, #5 10: e12fff1e bx lr After: static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) { return !!(ver->impl_id == TEE_IMPL_ID_OPTEE); 0: e5900000 ldr r0, [r0] } 4: e2400001 sub r0, r0, #1 8: e16f0f10 clz r0, r0 c: e1a002a0 lsr r0, r0, #5 10: e12fff1e bx lr I'm in favor of keeping the current version. -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com 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 lists.trustedfirmware.org (lists.trustedfirmware.org [18.214.241.189]) (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 030B6D6B084 for ; Thu, 29 Jan 2026 16:05:54 +0000 (UTC) Received: from lists.trustedfirmware.org (localhost [127.0.0.1]) by lists.trustedfirmware.org (Postfix) with ESMTP id 338EC436FD for ; Thu, 29 Jan 2026 16:05:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.trustedfirmware.org; s=2024; t=1769702754; bh=yVdibtwtGBdtM6zRoTTns3ysNbJg04ECgBNHy8kebSA=; h=Date:To:Subject:References:In-Reply-To:CC:List-Id:List-Archive: List-Help:List-Owner:List-Post:List-Subscribe:List-Unsubscribe: From:Reply-To:From; b=2D1ON91wqYeQOQ35rhXwFjoTjqzl0sUX54h1swsrPHQZgKmugYrEFFAvtILcgo6wj 8j8mpF2oZRNHvFOWYXzBdEOA0yzax4VwOnhaiOwKOVSRl6lpuO1QMnYrx8MqbEgWI+ 0vxwJZeFB/aY5wGFcXPEFVQcKRdON1Fju1tzij2qmD1d9FFBOF43IbUU2iQpkaIoW8 zKuMtv5zYkk98pxw+0bLLijm5fl1kL2FpVfbJuZF9aABgaeQ9dTzKNSmnAGEj7g0uF YAN3wQo2rOKV3JOw0M87F4jvinfPl/ksCk37FIrrB4wBzqtLirABcXM9uRL2WMcjDG +pSTrNGZ0U07A== Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) by lists.trustedfirmware.org (Postfix) with ESMTPS id B343A432A4 for ; Thu, 29 Jan 2026 16:05:33 +0000 (UTC) Authentication-Results: lists.trustedfirmware.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256 header.s=dkim header.b=mNSQY84L; dkim-atps=neutral Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 820DB1A2B01; Thu, 29 Jan 2026 16:05:32 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 4FCDF60746; Thu, 29 Jan 2026 16:05:32 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id C84C6119A8095; Thu, 29 Jan 2026 17:05:27 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1769702731; h=from:subject:date:message-id:to:cc:mime-version:content-type: in-reply-to:references; bh=Lc6wWk4IgTT559wWGEQNQjCDMW6utgy5FoBxVvSG2KM=; b=mNSQY84LQ52ZnscGD18IByJvZJQQIacVebk2t/plG/whMwn+83Zl1E9OvoWX2V2RxCfoxS J7FKlupj1VB7e6rJFirr6RfK/Oy8A6bsRNzcw474UsjN/FbndmiovBhMgwm4YRKoBwKFmx 3ZeTXY3A03ZQLaJOCIiO8R9mHEDa7oyn4WPEqgrGwV6YrglWUK6/soN5WeE49FI13rIEZA q4eMBtWPKykfEWe2ps7aGWr4/JW4mG1Uq3VhlwwNdXdiVcqnGgeBHoWH5R9jClm0TjLX7V OKWIWCnc7iGZ2Eb/+sESPRrxzaJ8ZnvdKXHvmTHen/Ais5igGxDQBGU8jw1rrw== Date: Thu, 29 Jan 2026 17:05:27 +0100 To: rouven.czerwinski@linaro.org Subject: Re: [PATCH 3/3] rtc: optee: simplify OP-TEE context match Message-ID: <202601291605277bc279f4@mail.local> References: <20260126-optee-simplify-context-match-v1-0-d4104e526cb6@linaro.org> <20260126-optee-simplify-context-match-v1-3-d4104e526cb6@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260126-optee-simplify-context-match-v1-3-d4104e526cb6@linaro.org> X-Last-TLS-Session-Version: TLSv1.3 X-Rspamd-Action: no action X-Spamd-Result: default: False [-4.00 / 15.00]; BAYES_HAM(-3.00)[99.99%]; DMARC_POLICY_ALLOW(-0.50)[bootlin.com,reject]; R_DKIM_ALLOW(-0.20)[bootlin.com:s=dkim]; R_SPF_ALLOW(-0.20)[+ip4:185.246.84.56]; MIME_GOOD(-0.10)[text/plain]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; ASN(0.00)[asn:21409, ipnet:185.246.84.0/22, country:FR]; MISSING_XM_UA(0.00)[]; NEURAL_HAM(-0.00)[-1.000]; MIME_TRACE(0.00)[0:+]; RCPT_COUNT_SEVEN(0.00)[10]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RECEIVED_HELO_LOCALHOST(0.00)[]; DNSWL_BLOCKED(0.00)[185.246.84.56:from]; DKIM_TRACE(0.00)[bootlin.com:+] X-Rspamd-Server: lists.trustedfirmware.org X-Rspamd-Queue-Id: B343A432A4 X-Spamd-Bar: --- Message-ID-Hash: 7I7ZYCQS3FUTJCLFNO2M2U4U47C4E3VU X-Message-ID-Hash: 7I7ZYCQS3FUTJCLFNO2M2U4U47C4E3VU X-MailFrom: alexandre.belloni@bootlin.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-op-tee.lists.trustedfirmware.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Sumit Garg , Olivia Mackall , Herbert Xu , =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , op-tee@lists.trustedfirmware.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-rtc@vger.kernel.org X-Mailman-Version: 3.3.5 Precedence: list List-Id: Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: From: Alexandre Belloni via OP-TEE Reply-To: Alexandre Belloni On 26/01/2026 11:11:26+0100, Rouven Czerwinski via B4 Relay wrote: > From: Rouven Czerwinski > > Simplify the TEE implementor ID match by returning the boolean > expression directly instead of going through an if/else. > > Signed-off-by: Rouven Czerwinski > --- > drivers/rtc/rtc-optee.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c > index 184c6d142801..2f18be3de684 100644 > --- a/drivers/rtc/rtc-optee.c > +++ b/drivers/rtc/rtc-optee.c > @@ -541,10 +541,7 @@ static int optee_rtc_read_info(struct device *dev, struct rtc_device *rtc, > > static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) > { > - if (ver->impl_id == TEE_IMPL_ID_OPTEE) > - return 1; > - else > - return 0; > + return (ver->impl_id == TEE_IMPL_ID_OPTEE); I guess the correct way to do this would be: return !!(ver->impl_id == TEE_IMPL_ID_OPTEE); But is this change actually generating better code? Before: static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) { if (ver->impl_id == TEE_IMPL_ID_OPTEE) 0: e5900000 ldr r0, [r0] return 1; else return 0; } 4: e2400001 sub r0, r0, #1 8: e16f0f10 clz r0, r0 c: e1a002a0 lsr r0, r0, #5 10: e12fff1e bx lr After: static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) { return !!(ver->impl_id == TEE_IMPL_ID_OPTEE); 0: e5900000 ldr r0, [r0] } 4: e2400001 sub r0, r0, #1 8: e16f0f10 clz r0, r0 c: e1a002a0 lsr r0, r0, #5 10: e12fff1e bx lr I'm in favor of keeping the current version. -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com