From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZriip+0jNHCeBxa+Fi3z3th2EMO1ROlbfMjeH9InyNQfnncU9ySe/Do+v2l/9EGPGBl9SwK ARC-Seal: i=1; a=rsa-sha256; t=1524837739; cv=none; d=google.com; s=arc-20160816; b=uw2Kr14c7hbismW1IWY67k0OFxykfgfSfUAbO0S3X78HiBq6vQjRJHZGE6FIONNu8Z gkybEQ4SAIVEx4wtDsH9chtedyCX2Skj5AJ0tUzFVNqUFSjPRRsgwS1XTZgidkKVSsej PaGILkoo6h0OfCeV5E9sazRDRjq3TXRq6rolp7sKdWPpMR56pmTENatnAZlj2mxRTb+m 4F+A5ldZDk0w1LNbyDbU13I+OvIFgUEz2VfYGwPcPZRW+jhBTLneHBsRtw5nVvSQtLhf UM3nGD30SFvBY9T4HhJS/Xjr/vNnHz+53P8l6EcZaZMOUHzCzNy7GSJUS7E6LzJHHwix Mf6w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dmarc-filter:arc-authentication-results; bh=89zKIG0dVRw8+HZAr+ooEd2Z68tnfk1tf0o3ngvaXmc=; b=PmSh151cVqUECAxpeyWt3udM0qt2H4eJLqVO2fFiEC8jh6L4UFolZaOXQDOExIcu2r PdrNb8mkVgu6EKoBuG9eGay91S+czciUvopy+WGHQonwtx6e2r9ifOyWbN3RWJhq42w3 Ax59VuEZR1jjFAHTQ6MyYZqkO2uhb/LeJZrrLTWQwEH2L3KypUDtb2LwwApXkD5a96gK xLJMzB0Rc9Z2PyQDaMw3DqoRZQg0hT2QK0KPbqZo21FxxB7W5CfiB8ySvd8x/6vZCthk cpXf1Jj9rVmM+yE/V7TKq3ZoVw0EJHN3YhEnpx/sJoDk6ufbWG8nHc6sY9VqB1B3/JOz u4xg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of srs0=4/0d=hq=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4/0d=HQ=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of srs0=4/0d=hq=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4/0d=HQ=linuxfoundation.org=gregkh@kernel.org DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 71C6621897 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=fail smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Martin Schwidefsky Subject: [PATCH 4.4 14/50] s390: add optimized array_index_mask_nospec Date: Fri, 27 Apr 2018 15:58:16 +0200 Message-Id: <20180427135656.542157500@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180427135655.623669681@linuxfoundation.org> References: <20180427135655.623669681@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1598908257042358835?= X-GMAIL-MSGID: =?utf-8?q?1598908257042358835?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin Schwidefsky [ Upstream commit e2dd833389cc4069a96b57bdd24227b5f52288f5 ] Add an optimized version of the array_index_mask_nospec function for s390 based on a compare and a subtract with borrow. Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman --- arch/s390/include/asm/barrier.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) --- a/arch/s390/include/asm/barrier.h +++ b/arch/s390/include/asm/barrier.h @@ -53,4 +53,28 @@ do { \ ___p1; \ }) +/** + * array_index_mask_nospec - generate a mask for array_idx() that is + * ~0UL when the bounds check succeeds and 0 otherwise + * @index: array element index + * @size: number of elements in array + */ +#define array_index_mask_nospec array_index_mask_nospec +static inline unsigned long array_index_mask_nospec(unsigned long index, + unsigned long size) +{ + unsigned long mask; + + if (__builtin_constant_p(size) && size > 0) { + asm(" clgr %2,%1\n" + " slbgr %0,%0\n" + :"=d" (mask) : "d" (size-1), "d" (index) :"cc"); + return mask; + } + asm(" clgr %1,%2\n" + " slbgr %0,%0\n" + :"=d" (mask) : "d" (size), "d" (index) :"cc"); + return ~mask; +} + #endif /* __ASM_BARRIER_H */