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received-spf: None (protection.outlook.com: ni.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: WyUQg6TBCj9xhI4rvxktoYgXSz5jw7hy0hP7xDbuRTGMBkzuo+qhHtz561zsFuL+d5d6luyG47eSYxuPTDR9Cy1xkkxyS/fC4Qa93xGhUVaso82LpnUiZfVDoJFwh1XN1oDDmp4H+Upy0/xtT2hKMB46XLy9jsj6NH21Cp/JZHv6hC0vxaykP54jd5Qm/p0brV3yw7JUDTldhaqKCxXFJxq65h9HZcyuqdwROdyQ0cR7e6eBEFZF0/xHB0r5M51VYeDEC0x/r2I0bnul8UOiwya0ywjLZ0a1yCELpK2FtPL/YkdUAJHOCpKdxCxOQp4uki0YbrYsUAYKNMtoGOnn9Uhq6eAh+blXfTxbYTwqNEU= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: ni.com X-MS-Exchange-CrossTenant-Network-Message-Id: cd9e9cd2-0421-4e6c-1319-08d62585e513 X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Sep 2018 21:03:52.7835 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 87ba1f9a-44cd-43a6-b008-6fdb45a5204e X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR04MB0741 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-09-28_09:,, signatures=0 X-Proofpoint-Spam-Details: rule=inbound_policy_notspam policy=inbound_policy score=30 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=769 adultscore=0 classifier=spam adjust=30 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1809280206 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following two patches solve an issue reported by Steffen Trumtrar and Tim Sander to the linux-rt-users mailing list. Namely, the wakeup of the watchdogd thread being starved by an RT task due to the hrtimer deferral through ktimersoftd (on PREEMPT_RT_FULL). The first patch adjusts the kthread_worker locking to make use of a raw spinlock, making it suitable for work item queueing from hardirq context on PREEMPT_RT. This patch can be applied directly to mainline without any functional change. The second patch adjusts the hrtimer used by the watchdog core to be a _HARD timer (and thus not deferred through ktimersoftd w/ PREEMPT_RT). This patch depends on hrtimer patches carried in the RT patch, and so should therefore land there. Cc: Guenter Roeck Cc: Steffen Trumtrar Cc: Tim Sander Julia Cartwright (2): kthread: convert worker lock to raw spinlock watchdog, rt: prevent deferral of watchdogd wakeup drivers/watchdog/watchdog_dev.c | 2 +- include/linux/kthread.h | 2 +- kernel/kthread.c | 42 ++++++++++++++++----------------- 3 files changed, 23 insertions(+), 23 deletions(-) --=20 2.18.0