From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3454413-1521618156-2-16206401562311858943 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enrosk.us-ascii, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='de', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-api-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521618155; b=QXClY6WUFMYfcF60/CepEyxRwQLOXML28FOphxc+fxoP+gi Wg2HIMhIQksRbFyOUVz9vkArj3mU2XzRiDYkH7ufZaIZNJ2a8Zbo/nRvlTHpvv4T 0FjaszjzvWYrmY3g7vQeMNRw1IwqZc8hRVTboSVYGa1/BoIsHHxE0h+m9BP4bhV9 gKX70WRtFtGxQsAlX7Wf3/ZU9Dt3AslK9GISfgkMw8p06hAb6uA3vyFE3tbmhFPJ aT1HABkoConLdh9yqlkjsWhudl4Iwjk6/X+H048tfCPpTlxWS87c1I5h0+UH7J3g sxW9NxnGxqzUYVHTRRptx9BKSS61gmvFet0HFgA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:sender:list-id; s=arctest; t=1521618155; bh=bSPGcsV9xHYATKBliDJcmY5rY/+K1a1F+DHpC/3SdIA=; b=SIJ/n7hqbhLc LsWHzR0jn6sQ1G4J82BwFMt7gAsgCRbSt6HjtX4nkblrpuiXLg/zaRPH5FYj2Fq5 jVjQAjc/0nt2Zys9GZ3CGqwK1wAz21yAIXFUfX5fPw1e3NkJT7pXJT7sGMwnLKFQ 9RTVCuGl7JSttYOh9T/Lkv1CShqTh1fmA0C85Q2Zl+d1y/HYL1qqF4loRnmzT6PX q5YWPuSGmX7x89z1niW+cQn1TyagpIrAxe1aYQL8dgHGI4yh6IWHzu8sSDqf5xfz OcTDKz6BTZyrN7Jc0kPqLzBiznRcPwQksyYc5fnf+SPOLgZLo5cQrepFUSOqoLta 59fgF0ZHww== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=Mv7pOuks x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=Mv7pOuks x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 X-ME-VSCategory: clean Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752383AbeCUHmc (ORCPT ); Wed, 21 Mar 2018 03:42:32 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:48360 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752304AbeCUHma (ORCPT ); Wed, 21 Mar 2018 03:42:30 -0400 From: Christoph Hellwig To: viro@zeniv.linux.org.uk Cc: Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 28/28] random: convert to ->poll_mask Date: Wed, 21 Mar 2018 08:40:32 +0100 Message-Id: <20180321074032.14211-29-hch@lst.de> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180321074032.14211-1-hch@lst.de> References: <20180321074032.14211-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-api-owner@vger.kernel.org X-Mailing-List: linux-api@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: The big change is that random_read_wait and random_write_wait are merged into a single waitqueue that uses keyed wakeups. Because wait_event_* doesn't know about that this will lead to occassional spurious wakeups in _random_read and add_hwgenerator_randomness, but wait_event_* is designed to handle these and were are not in a a hot path there. Signed-off-by: Christoph Hellwig --- drivers/char/random.c | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index e5b3d3ba4660..840d80b64431 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -401,8 +401,7 @@ static struct poolinfo { /* * Static global variables */ -static DECLARE_WAIT_QUEUE_HEAD(random_read_wait); -static DECLARE_WAIT_QUEUE_HEAD(random_write_wait); +static DECLARE_WAIT_QUEUE_HEAD(random_wait); static struct fasync_struct *fasync; static DEFINE_SPINLOCK(random_ready_list_lock); @@ -710,7 +709,7 @@ static void credit_entropy_bits(struct entropy_store *r, int nbits) /* should we wake readers? */ if (entropy_bits >= random_read_wakeup_bits) { - wake_up_interruptible(&random_read_wait); + wake_up_interruptible_poll(&random_wait, POLLIN); kill_fasync(&fasync, SIGIO, POLL_IN); } /* If the input pool is getting full, send some @@ -1293,7 +1292,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min, trace_debit_entropy(r->name, 8 * ibytes); if (ibytes && (r->entropy_count >> ENTROPY_SHIFT) < random_write_wakeup_bits) { - wake_up_interruptible(&random_write_wait); + wake_up_interruptible_poll(&random_wait, POLLOUT); kill_fasync(&fasync, SIGIO, POLL_OUT); } @@ -1748,7 +1747,7 @@ _random_read(int nonblock, char __user *buf, size_t nbytes) if (nonblock) return -EAGAIN; - wait_event_interruptible(random_read_wait, + wait_event_interruptible(random_wait, ENTROPY_BITS(&input_pool) >= random_read_wakeup_bits); if (signal_pending(current)) @@ -1784,14 +1783,17 @@ urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) return ret; } +static struct wait_queue_head * +random_get_poll_head(struct file *file, __poll_t events) +{ + return &random_wait; +} + static __poll_t -random_poll(struct file *file, poll_table * wait) +random_poll_mask(struct file *file, __poll_t events) { - __poll_t mask; + __poll_t mask = 0; - poll_wait(file, &random_read_wait, wait); - poll_wait(file, &random_write_wait, wait); - mask = 0; if (ENTROPY_BITS(&input_pool) >= random_read_wakeup_bits) mask |= EPOLLIN | EPOLLRDNORM; if (ENTROPY_BITS(&input_pool) < random_write_wakeup_bits) @@ -1890,7 +1892,8 @@ static int random_fasync(int fd, struct file *filp, int on) const struct file_operations random_fops = { .read = random_read, .write = random_write, - .poll = random_poll, + .get_poll_head = random_get_poll_head, + .poll_mask = random_poll_mask, .unlocked_ioctl = random_ioctl, .fasync = random_fasync, .llseek = noop_llseek, @@ -2223,7 +2226,7 @@ void add_hwgenerator_randomness(const char *buffer, size_t count, * We'll be woken up again once below random_write_wakeup_thresh, * or when the calling thread is about to terminate. */ - wait_event_interruptible(random_write_wait, kthread_should_stop() || + wait_event_interruptible(random_wait, kthread_should_stop() || ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits); mix_pool_bytes(poolp, buffer, count); credit_entropy_bits(poolp, entropy); -- 2.14.2