Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758109Ab1CaOw6 (ORCPT ); Thu, 31 Mar 2011 10:52:58 -0400 Received: from ppsw-50.csi.cam.ac.uk ([131.111.8.150]:57391 "EHLO ppsw-50.csi.cam.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758048Ab1CaOwv (ORCPT ); Thu, 31 Mar 2011 10:52:51 -0400 X-Cam-AntiVirus: no malware found X-Cam-SpamDetails: not scanned X-Cam-ScannerInfo: http://www.cam.ac.uk/cs/email/scanner/ From: Jonathan Cameron To: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Cc: arnd@arndb.de, tglx@linutronix.de, Jonathan Cameron Subject: [PATCH 04/21] staging:iio: remove ability to escalate events. Date: Thu, 31 Mar 2011 15:53:58 +0100 Message-Id: <1301583255-28468-5-git-send-email-jic23@cam.ac.uk> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1301583255-28468-1-git-send-email-jic23@cam.ac.uk> References: <1301583255-28468-1-git-send-email-jic23@cam.ac.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8921 Lines: 253 Whilst it is possible to output events to say buffers have passed a particular level there are no obvious reasons to actually do so. The upshot of this patch is that buffers will only ever have one threshold turned on at a time. This will need to propogated into some drivers (e.g. sca3000) Signed-off-by: Jonathan Cameron --- drivers/staging/iio/chrdev.h | 13 ------------- drivers/staging/iio/iio.h | 16 ++-------------- drivers/staging/iio/industrialio-core.c | 30 ++---------------------------- drivers/staging/iio/industrialio-ring.c | 23 ++--------------------- drivers/staging/iio/ring_generic.h | 3 --- drivers/staging/iio/ring_sw.c | 14 +------------- 6 files changed, 7 insertions(+), 92 deletions(-) diff --git a/drivers/staging/iio/chrdev.h b/drivers/staging/iio/chrdev.h index 95b439e..c1e86a9 100644 --- a/drivers/staging/iio/chrdev.h +++ b/drivers/staging/iio/chrdev.h @@ -45,23 +45,10 @@ struct iio_event_data { * struct iio_detected_event_list - list element for events that have occured * @list: linked list header * @ev: the event itself - * @shared_pointer: used when the event is shared - i.e. can be escallated - * on demand (eg ring buffer 50%->100% full) */ struct iio_detected_event_list { struct list_head list; struct iio_event_data ev; - struct iio_shared_ev_pointer *shared_pointer; -}; -/** - * struct iio_shared_ev_pointer - allows shared events to identify if currently - * in the detected event list - * @ev_p: pointer to detected event list element (null if not in list) - * @lock: protect this element to prevent simultaneous edit and remove - */ -struct iio_shared_ev_pointer { - struct iio_detected_event_list *ev_p; - spinlock_t lock; }; /** diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h index 578d078..1496f0b 100644 --- a/drivers/staging/iio/iio.h +++ b/drivers/staging/iio/iio.h @@ -346,22 +346,10 @@ int iio_push_event(struct iio_dev *dev_info, * @ev_int: the event interface to which we are pushing the event * @ev_code: the outgoing event code * @timestamp: timestamp of the event - * @shared_pointer_p: the shared event pointer **/ int __iio_push_event(struct iio_event_interface *ev_int, - int ev_code, - s64 timestamp, - struct iio_shared_ev_pointer* - shared_pointer_p); -/** - * __iio_change_event() - change an event code in case of event escalation - * @ev: the event to be changed - * @ev_code: new event code - * @timestamp: new timestamp - **/ -void __iio_change_event(struct iio_detected_event_list *ev, - int ev_code, - s64 timestamp); + int ev_code, + s64 timestamp); /** * iio_setup_ev_int() - configure an event interface (chrdev) diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c index 809588f..5b7b5df 100644 --- a/drivers/staging/iio/industrialio-core.c +++ b/drivers/staging/iio/industrialio-core.c @@ -66,15 +66,6 @@ static const char * const iio_chan_info_postfix[] = { [IIO_CHAN_INFO_CALIBBIAS_SHARED/2] = "calibbias", }; -void __iio_change_event(struct iio_detected_event_list *ev, - int ev_code, - s64 timestamp) -{ - ev->ev.id = ev_code; - ev->ev.timestamp = timestamp; -} -EXPORT_SYMBOL(__iio_change_event); - /* Used both in the interrupt line put events and the ring buffer ones */ /* Note that in it's current form someone has to be listening before events @@ -83,9 +74,7 @@ EXPORT_SYMBOL(__iio_change_event); */ int __iio_push_event(struct iio_event_interface *ev_int, int ev_code, - s64 timestamp, - struct iio_shared_ev_pointer * - shared_pointer_p) + s64 timestamp) { struct iio_detected_event_list *ev; int ret = 0; @@ -105,9 +94,6 @@ int __iio_push_event(struct iio_event_interface *ev_int, } ev->ev.id = ev_code; ev->ev.timestamp = timestamp; - ev->shared_pointer = shared_pointer_p; - if (ev->shared_pointer) - shared_pointer_p->ev_p = ev; list_add_tail(&ev->list, &ev_int->det_events.list); ev_int->current_events++; @@ -127,7 +113,7 @@ int iio_push_event(struct iio_dev *dev_info, s64 timestamp) { return __iio_push_event(&dev_info->event_interfaces[ev_line], - ev_code, timestamp, NULL); + ev_code, timestamp); } EXPORT_SYMBOL(iio_push_event); @@ -295,18 +281,6 @@ static ssize_t iio_event_chrdev_read(struct file *filep, list_del(&el->list); ev_int->current_events--; mutex_unlock(&ev_int->event_list_lock); - /* - * Possible concurency issue if an update of this event is on its way - * through. May lead to new event being removed whilst the reported - * event was the unescalated event. In typical use case this is not a - * problem as userspace will say read half the buffer due to a 50% - * full event which would make the correct 100% full incorrect anyway. - */ - if (el->shared_pointer) { - spin_lock(&el->shared_pointer->lock); - (el->shared_pointer->ev_p) = NULL; - spin_unlock(&el->shared_pointer->lock); - } kfree(el); return len; diff --git a/drivers/staging/iio/industrialio-ring.c b/drivers/staging/iio/industrialio-ring.c index 1dfbc6e..466b9fa 100644 --- a/drivers/staging/iio/industrialio-ring.c +++ b/drivers/staging/iio/industrialio-ring.c @@ -27,28 +27,11 @@ int iio_push_ring_event(struct iio_ring_buffer *ring_buf, s64 timestamp) { return __iio_push_event(&ring_buf->ev_int, - event_code, - timestamp, - &ring_buf->shared_ev_pointer); + event_code, + timestamp); } EXPORT_SYMBOL(iio_push_ring_event); -int iio_push_or_escallate_ring_event(struct iio_ring_buffer *ring_buf, - int event_code, - s64 timestamp) -{ - if (ring_buf->shared_ev_pointer.ev_p) - __iio_change_event(ring_buf->shared_ev_pointer.ev_p, - event_code, - timestamp); - else - return iio_push_ring_event(ring_buf, - event_code, - timestamp); - return 0; -} -EXPORT_SYMBOL(iio_push_or_escallate_ring_event); - /** * iio_ring_open() - chrdev file open for ring buffer access * @@ -228,8 +211,6 @@ void iio_ring_buffer_init(struct iio_ring_buffer *ring, ring->indio_dev = dev_info; ring->ev_int.private = ring; ring->access_handler.private = ring; - ring->shared_ev_pointer.ev_p = NULL; - spin_lock_init(&ring->shared_ev_pointer.lock); } EXPORT_SYMBOL(iio_ring_buffer_init); diff --git a/drivers/staging/iio/ring_generic.h b/drivers/staging/iio/ring_generic.h index 6c7e073..320a11d 100644 --- a/drivers/staging/iio/ring_generic.h +++ b/drivers/staging/iio/ring_generic.h @@ -107,8 +107,6 @@ struct iio_ring_access_funcs { * @scan_timestamp: [INTERN] does the scan mode include a timestamp * @access_handler: [INTERN] chrdev access handling * @ev_int: [INTERN] chrdev interface for the event chrdev - * @shared_ev_pointer: [INTERN] the shared event pointer to allow escalation of - * events * @access: [DRIVER] ring access functions associated with the * implementation. * @preenable: [DRIVER] function to run prior to marking ring enabled @@ -133,7 +131,6 @@ struct iio_ring_buffer { bool scan_timestamp; struct iio_handler access_handler; struct iio_event_interface ev_int; - struct iio_shared_ev_pointer shared_ev_pointer; struct iio_ring_access_funcs access; int (*preenable)(struct iio_dev *); int (*postenable)(struct iio_dev *); diff --git a/drivers/staging/iio/ring_sw.c b/drivers/staging/iio/ring_sw.c index ea0015e..0004814 100644 --- a/drivers/staging/iio/ring_sw.c +++ b/drivers/staging/iio/ring_sw.c @@ -123,14 +123,6 @@ static int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring, */ if (change_test_ptr == ring->read_p) ring->read_p = temp_ptr; - - spin_lock(&ring->buf.shared_ev_pointer.lock); - - ret = iio_push_or_escallate_ring_event(&ring->buf, - IIO_EVENT_CODE_RING_100_FULL, timestamp); - spin_unlock(&ring->buf.shared_ev_pointer.lock); - if (ret) - goto error_ret; } /* investigate if our event barrier has been passed */ /* There are definite 'issues' with this and chances of @@ -140,15 +132,11 @@ static int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring, if (ring->half_p == ring->data + ring->buf.length*ring->buf.bytes_per_datum) ring->half_p = ring->data; if (ring->half_p == ring->read_p) { - spin_lock(&ring->buf.shared_ev_pointer.lock); code = IIO_EVENT_CODE_RING_50_FULL; ret = __iio_push_event(&ring->buf.ev_int, code, - timestamp, - &ring->buf.shared_ev_pointer); - spin_unlock(&ring->buf.shared_ev_pointer.lock); + timestamp); } -error_ret: return ret; } -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/