linux-kernel - [char-misc-next 2/5] mei: keep the device awake during reads in chunks

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] [day] [month] [year] [list]

Message-Id: <1444737761-19668-2-git-send-email-tomas.winkler@intel.com>
Date:	Tue, 13 Oct 2015 15:02:38 +0300
From:	Tomas Winkler <tomas.winkler@...el.com>
To:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	Alexander Usyskin <alexander.usyskin@...el.com>,
	linux-kernel@...r.kernel.org,
	Tomas Winkler <tomas.winkler@...el.com>
Subject: [char-misc-next 2/5] mei: keep the device awake during reads in chunks

From: Alexander Usyskin <alexander.usyskin@...el.com>

Long messages are read in chunks, to prevent trashing runtime pm between
the reading of the chunks we call pm_runtime_mark_last_busy() on
non-final chunk message as the next chunk of the same message will be
received immediately in the next interrupt with high probablity.

Signed-off-by: Alexander Usyskin <alexander.usyskin@...el.com>
Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---
 drivers/misc/mei/interrupt.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index c418d7888994..64b568a0268d 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -21,6 +21,7 @@
 #include <linux/fs.h>
 #include <linux/jiffies.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
 
 #include <linux/mei.h>
 
@@ -147,6 +148,9 @@ int mei_cl_irq_read_msg(struct mei_cl *cl,
 		cb->read_time = jiffies;
 		cl_dbg(dev, cl, "completed read length = %lu\n", cb->buf_idx);
 		list_move_tail(&cb->list, &complete_list->list);
+	} else {
+		pm_runtime_mark_last_busy(dev->dev);
+		pm_request_autosuspend(dev->dev);
 	}
 
 out:
-- 
2.4.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/