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 DCF57FA3742 for ; Thu, 27 Oct 2022 13:07:29 +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:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Bg657f8DmSTnh9zaC9wu/MH6gzGL2GSg32zyHBV1rx4=; b=dxdqTRxsyemF/r i5s2C2DhWYPIS6989v5XB00lOn+oKCE81fg6GSyU5pzUAcNIqyNYzbzceR8RGyQch1o9wb/BaqNbc LnrI4uvFZKNe8U+j7eM0MjdpNc/I17gEdAHGL0Lw/1L7PPVaSRDauvL5vaWr06Jmj8UOL4Cs2eJc/ 36r+yCIl/b31lQhVvDBddyoWUBW3LbWlRe9Q/BXSwkzwyAb8tRWLzJTD1pXqAM7FwWdj9WJkoUmvO lwS5Ne0TOg7k8Oa6wSBpfo7ecHxhMbrnR1PkclHTpKZ/QXy7E2p9WPJIKpW2oVEMOZyz3YqEfXo8U GkBl52eKa++vg0ISI8Dw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oo2bP-00DLEQ-KF; Thu, 27 Oct 2022 13:07:19 +0000 Received: from gloria.sntech.de ([185.11.138.130]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oo2a0-00DKTn-Pa for linux-riscv@lists.infradead.org; Thu, 27 Oct 2022 13:05:54 +0000 Received: from ip5b412258.dynamic.kabel-deutschland.de ([91.65.34.88] helo=diego.localnet) by gloria.sntech.de with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oo2Zu-0000Vs-WD; Thu, 27 Oct 2022 15:05:47 +0200 From: Heiko =?ISO-8859-1?Q?St=FCbner?= To: linux-riscv@lists.infradead.org, Andrew Jones Cc: Palmer Dabbelt , Paul Walmsley , Albert Ou , Conor Dooley , Anup Patel , Atish Patra Subject: Re: [PATCH v2 1/3] RISC-V: Improve use of isa2hwcap[] Date: Thu, 27 Oct 2022 15:05:46 +0200 Message-ID: <4911272.GXAFRqVoOG@diego> In-Reply-To: <20221024091309.406906-2-ajones@ventanamicro.com> References: <20221024091309.406906-1-ajones@ventanamicro.com> <20221024091309.406906-2-ajones@ventanamicro.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221027_060552_895643_DCAEBE83 X-CRM114-Status: GOOD ( 17.24 ) 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="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Am Montag, 24. Oktober 2022, 11:13:07 CEST schrieb Andrew Jones: > Improve isa2hwcap[] by removing it from static storage, as > riscv_fill_hwcap() is only called once, and by reducing its size > from 256 bytes to 26. The latter improvement is possible because > isa2hwcap[] will never be indexed with capital letters and we can > precompute the offsets from 'a'. > > No functional change intended. > > Signed-off-by: Andrew Jones > Reviewed-by: Conor Dooley Reviewed-by: Heiko Stuebner > --- > arch/riscv/kernel/cpufeature.c | 20 +++++++++++--------- > 1 file changed, 11 insertions(+), 9 deletions(-) > > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c > index 694267d1fe81..4677320d7e31 100644 > --- a/arch/riscv/kernel/cpufeature.c > +++ b/arch/riscv/kernel/cpufeature.c > @@ -74,15 +74,15 @@ void __init riscv_fill_hwcap(void) > const char *isa; > char print_str[NUM_ALPHA_EXTS + 1]; > int i, j, rc; > - static unsigned long isa2hwcap[256] = {0}; > + unsigned long isa2hwcap[26] = {0}; > unsigned long hartid; > > - isa2hwcap['i'] = isa2hwcap['I'] = COMPAT_HWCAP_ISA_I; > - isa2hwcap['m'] = isa2hwcap['M'] = COMPAT_HWCAP_ISA_M; > - isa2hwcap['a'] = isa2hwcap['A'] = COMPAT_HWCAP_ISA_A; > - isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F; > - isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D; > - isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C; > + isa2hwcap['i' - 'a'] = COMPAT_HWCAP_ISA_I; > + isa2hwcap['m' - 'a'] = COMPAT_HWCAP_ISA_M; > + isa2hwcap['a' - 'a'] = COMPAT_HWCAP_ISA_A; > + isa2hwcap['f' - 'a'] = COMPAT_HWCAP_ISA_F; > + isa2hwcap['d' - 'a'] = COMPAT_HWCAP_ISA_D; > + isa2hwcap['c' - 'a'] = COMPAT_HWCAP_ISA_C; > > elf_hwcap = 0; > > @@ -196,8 +196,10 @@ void __init riscv_fill_hwcap(void) > if (unlikely(ext_err)) > continue; > if (!ext_long) { > - this_hwcap |= isa2hwcap[(unsigned char)(*ext)]; > - set_bit(*ext - 'a', this_isa); > + int nr = *ext - 'a'; > + > + this_hwcap |= isa2hwcap[nr]; > + set_bit(nr, this_isa); > } else { > SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF); > SET_ISA_EXT_MAP("svpbmt", RISCV_ISA_EXT_SVPBMT); > _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv