From mboxrd@z Thu Jan 1 00:00:00 1970 From: Suzuki.Poulose@arm.com (Suzuki K Poulose) Date: Mon, 5 Jun 2017 10:24:41 +0100 Subject: [PATCH v1 2/4] coresight: add and remove panic callback for sink In-Reply-To: <1496500976-18362-3-git-send-email-leo.yan@linaro.org> References: <1496500976-18362-1-git-send-email-leo.yan@linaro.org> <1496500976-18362-3-git-send-email-leo.yan@linaro.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/06/17 15:42, Leo Yan wrote: > If the sink device has panic callback function, add the panic callback > node for coresight panic dump list when the sink device is enabled; > also cleanup the node when the sink device is disabled. > > Signed-off-by: Leo Yan > --- > drivers/hwtracing/coresight/coresight.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c > index 0c37356..5928886 100644 > --- a/drivers/hwtracing/coresight/coresight.c > +++ b/drivers/hwtracing/coresight/coresight.c > @@ -138,6 +138,13 @@ static int coresight_enable_sink(struct coresight_device *csdev, u32 mode) > if (ret) > return ret; > } > + > + /* Add kernel panic callback */ > + if (sink_ops(csdev)->panic_cb) { > + ret = coresight_add_panic_cb(csdev); > + if (ret) > + return ret; > + } > csdev->enable = true; > } > > @@ -149,6 +156,10 @@ static int coresight_enable_sink(struct coresight_device *csdev, u32 mode) > static void coresight_disable_sink(struct coresight_device *csdev) > { > if (atomic_dec_return(csdev->refcnt) == 0) { > + /* Remove kernel panic callback */ > + if (sink_ops(csdev)->panic_cb) > + coresight_del_panic_cb(csdev); > + > if (sink_ops(csdev)->disable) { > sink_ops(csdev)->disable(csdev); > csdev->enable = false; > Just a thought, instead of adding/deleting every time the sink is enabled, could we add/del the device once for-ever and let the panic_cb decide to dump it based on whether the device was active or not ? Suzuki