linux-kernel - [PATCH 04/49] iio: fix opencoded for_each_set

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220210224933.379149-5-yury.norov@gmail.com>
Date:   Thu, 10 Feb 2022 14:48:48 -0800
From:   Yury Norov <yury.norov@...il.com>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org, Jonathan Cameron <jic23@...nel.org>,
        Lars-Peter Clausen <lars@...afoo.de>,
        Alexandru Ardelean <alexandru.ardelean@...log.com>,
        Nathan Chancellor <nathan@...nel.org>,
        linux-iio@...r.kernel.org
Subject: [PATCH 04/49] iio: fix opencoded for_each_set_bit()

iio_simple_dummy_trigger_h() is mostly an opencoded for_each_set_bit().
Using for_each_set_bit() make code much cleaner, and more effective.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---
 drivers/iio/dummy/iio_simple_dummy_buffer.c | 48 ++++++++-------------
 1 file changed, 19 insertions(+), 29 deletions(-)

diff --git a/drivers/iio/dummy/iio_simple_dummy_buffer.c b/drivers/iio/dummy/iio_simple_dummy_buffer.c
index d81c2b2dad82..3bc1b7529e2a 100644
--- a/drivers/iio/dummy/iio_simple_dummy_buffer.c
+++ b/drivers/iio/dummy/iio_simple_dummy_buffer.c
@@ -45,41 +45,31 @@ static irqreturn_t iio_simple_dummy_trigger_h(int irq, void *p)
 {
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
+	int i = 0, j;
 	u16 *data;
 
 	data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
 	if (!data)
 		goto done;
 
-	if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength)) {
-		/*
-		 * Three common options here:
-		 * hardware scans: certain combinations of channels make
-		 *   up a fast read.  The capture will consist of all of them.
-		 *   Hence we just call the grab data function and fill the
-		 *   buffer without processing.
-		 * software scans: can be considered to be random access
-		 *   so efficient reading is just a case of minimal bus
-		 *   transactions.
-		 * software culled hardware scans:
-		 *   occasionally a driver may process the nearest hardware
-		 *   scan to avoid storing elements that are not desired. This
-		 *   is the fiddliest option by far.
-		 * Here let's pretend we have random access. And the values are
-		 * in the constant table fakedata.
-		 */
-		int i, j;
-
-		for (i = 0, j = 0;
-		     i < bitmap_weight(indio_dev->active_scan_mask,
-				       indio_dev->masklength);
-		     i++, j++) {
-			j = find_next_bit(indio_dev->active_scan_mask,
-					  indio_dev->masklength, j);
-			/* random access read from the 'device' */
-			data[i] = fakedata[j];
-		}
-	}
+	/*
+	 * Three common options here:
+	 * hardware scans: certain combinations of channels make
+	 *   up a fast read.  The capture will consist of all of them.
+	 *   Hence we just call the grab data function and fill the
+	 *   buffer without processing.
+	 * software scans: can be considered to be random access
+	 *   so efficient reading is just a case of minimal bus
+	 *   transactions.
+	 * software culled hardware scans:
+	 *   occasionally a driver may process the nearest hardware
+	 *   scan to avoid storing elements that are not desired. This
+	 *   is the fiddliest option by far.
+	 * Here let's pretend we have random access. And the values are
+	 * in the constant table fakedata.
+	 */
+	for_each_set_bit(j, indio_dev->active_scan_mask, indio_dev->masklength)
+		data[i++] = fakedata[j];
 
 	iio_push_to_buffers_with_timestamp(indio_dev, data,
 					   iio_get_time_ns(indio_dev));
-- 
2.32.0