Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756070AbdIRPd6 (ORCPT ); Mon, 18 Sep 2017 11:33:58 -0400 Received: from mga01.intel.com ([192.55.52.88]:32764 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755417AbdIRPbC (ORCPT ); Mon, 18 Sep 2017 11:31:02 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.42,413,1500966000"; d="scan'208";a="1220359574" From: Mika Westerberg To: Greg Kroah-Hartman , "David S . Miller" Cc: Andreas Noever , Michael Jamet , Yehezkel Bernat , Amir Levy , Mario.Limonciello@dell.com, Lukas Wunner , Andy Shevchenko , Mika Westerberg , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 11/16] thunderbolt: Use spinlock in ring serialization Date: Mon, 18 Sep 2017 18:30:44 +0300 Message-Id: <20170918153049.44185-12-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170918153049.44185-1-mika.westerberg@linux.intel.com> References: <20170918153049.44185-1-mika.westerberg@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4045 Lines: 135 This makes it possible to enqueue frames also from atomic context which is needed for example, when networking packets are sent over a Thunderbolt cable. Signed-off-by: Mika Westerberg Reviewed-by: Michael Jamet Reviewed-by: Yehezkel Bernat --- drivers/thunderbolt/nhi.c | 26 ++++++++++++++------------ include/linux/thunderbolt.h | 2 +- 2 files changed, 15 insertions(+), 13 deletions(-) diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c index 4704ccd20c84..d1ad37c6eccf 100644 --- a/drivers/thunderbolt/nhi.c +++ b/drivers/thunderbolt/nhi.c @@ -212,8 +212,10 @@ static void ring_work(struct work_struct *work) struct tb_ring *ring = container_of(work, typeof(*ring), work); struct ring_frame *frame; bool canceled = false; + unsigned long flags; LIST_HEAD(done); - mutex_lock(&ring->lock); + + spin_lock_irqsave(&ring->lock, flags); if (!ring->running) { /* Move all frames to done and mark them as canceled. */ @@ -241,7 +243,8 @@ static void ring_work(struct work_struct *work) ring_write_descriptors(ring); invoke_callback: - mutex_unlock(&ring->lock); /* allow callbacks to schedule new work */ + /* allow callbacks to schedule new work */ + spin_unlock_irqrestore(&ring->lock, flags); while (!list_empty(&done)) { frame = list_first_entry(&done, typeof(*frame), list); /* @@ -255,15 +258,17 @@ static void ring_work(struct work_struct *work) int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame) { + unsigned long flags; int ret = 0; - mutex_lock(&ring->lock); + + spin_lock_irqsave(&ring->lock, flags); if (ring->running) { list_add_tail(&frame->list, &ring->queue); ring_write_descriptors(ring); } else { ret = -ESHUTDOWN; } - mutex_unlock(&ring->lock); + spin_unlock_irqrestore(&ring->lock, flags); return ret; } EXPORT_SYMBOL_GPL(__tb_ring_enqueue); @@ -338,7 +343,7 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size, if (!ring) goto err; - mutex_init(&ring->lock); + spin_lock_init(&ring->lock); INIT_LIST_HEAD(&ring->queue); INIT_LIST_HEAD(&ring->in_flight); INIT_WORK(&ring->work, ring_work); @@ -371,8 +376,6 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size, return ring; err: - if (ring) - mutex_destroy(&ring->lock); kfree(ring); mutex_unlock(&nhi->lock); return NULL; @@ -419,7 +422,7 @@ void tb_ring_start(struct tb_ring *ring) u32 flags; mutex_lock(&ring->nhi->lock); - mutex_lock(&ring->lock); + spin_lock_irq(&ring->lock); if (ring->nhi->going_away) goto err; if (ring->running) { @@ -466,7 +469,7 @@ void tb_ring_start(struct tb_ring *ring) ring_interrupt_active(ring, true); ring->running = true; err: - mutex_unlock(&ring->lock); + spin_unlock_irq(&ring->lock); mutex_unlock(&ring->nhi->lock); } EXPORT_SYMBOL_GPL(tb_ring_start); @@ -487,7 +490,7 @@ EXPORT_SYMBOL_GPL(tb_ring_start); void tb_ring_stop(struct tb_ring *ring) { mutex_lock(&ring->nhi->lock); - mutex_lock(&ring->lock); + spin_lock_irq(&ring->lock); dev_info(&ring->nhi->pdev->dev, "stopping %s %d\n", RING_TYPE(ring), ring->hop); if (ring->nhi->going_away) @@ -508,7 +511,7 @@ void tb_ring_stop(struct tb_ring *ring) ring->running = false; err: - mutex_unlock(&ring->lock); + spin_unlock_irq(&ring->lock); mutex_unlock(&ring->nhi->lock); /* @@ -568,7 +571,6 @@ void tb_ring_free(struct tb_ring *ring) * to finish before freeing the ring. */ flush_work(&ring->work); - mutex_destroy(&ring->lock); kfree(ring); } EXPORT_SYMBOL_GPL(tb_ring_free); diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h index fac4ff62c0de..51af0a5fa52f 100644 --- a/include/linux/thunderbolt.h +++ b/include/linux/thunderbolt.h @@ -448,7 +448,7 @@ struct tb_nhi { * @eof_mask: Bit mask used to detect end of frame PDF */ struct tb_ring { - struct mutex lock; + spinlock_t lock; struct tb_nhi *nhi; int size; int hop; -- 2.13.5