From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f169.google.com ([209.85.212.169]:63428 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751240AbaKETwH (ORCPT ); Wed, 5 Nov 2014 14:52:07 -0500 Received: by mail-wi0-f169.google.com with SMTP id n3so12407787wiv.0 for ; Wed, 05 Nov 2014 11:52:06 -0800 (PST) From: Alexander Aring Subject: [PATCH bluetooth-next 01/18] ieee802154: rework wpan_phy index assignment Date: Wed, 5 Nov 2014 20:51:12 +0100 Message-Id: <1415217089-24919-2-git-send-email-alex.aring@gmail.com> In-Reply-To: <1415217089-24919-1-git-send-email-alex.aring@gmail.com> References: <1415217089-24919-1-git-send-email-alex.aring@gmail.com> Sender: linux-wpan-owner@vger.kernel.org List-ID: To: linux-wpan@vger.kernel.org Cc: kernel@pengutronix.de, Alexander Aring This patch reworks the wpan_phy index incrementation. It's now similar like wireless wiphy index incrementation. We move the wpan_phy index attribute inside of cfg802154_registered_device and use atomic operations instead locking mechanism via wpan_phy_mutex. Signed-off-by: Alexander Aring --- include/net/cfg802154.h | 1 - net/ieee802154/core.c | 30 +++++++++++------------------- net/ieee802154/core.h | 3 +++ 3 files changed, 14 insertions(+), 20 deletions(-) diff --git a/include/net/cfg802154.h b/include/net/cfg802154.h index 864bce2..29c6de5 100644 --- a/include/net/cfg802154.h +++ b/include/net/cfg802154.h @@ -61,7 +61,6 @@ struct wpan_phy { s32 cca_ed_level; struct device dev; - int idx; char priv[0] __aligned(NETDEV_ALIGN); }; diff --git a/net/ieee802154/core.c b/net/ieee802154/core.c index ed5b014..d1cd0ed 100644 --- a/net/ieee802154/core.c +++ b/net/ieee802154/core.c @@ -23,9 +23,6 @@ #include "sysfs.h" #include "core.h" -static DEFINE_MUTEX(wpan_phy_mutex); -static int wpan_phy_idx; - static int wpan_phy_match(struct device *dev, const void *data) { return !strcmp(dev_name(dev), (const char *)data); @@ -72,14 +69,10 @@ int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data), } EXPORT_SYMBOL(wpan_phy_for_each); -static int wpan_phy_idx_valid(int idx) -{ - return idx >= 0; -} - struct wpan_phy * wpan_phy_alloc(const struct cfg802154_ops *ops, size_t priv_size) { + static atomic_t wpan_phy_counter = ATOMIC_INIT(0); struct cfg802154_registered_device *rdev; size_t alloc_size; @@ -90,28 +83,27 @@ wpan_phy_alloc(const struct cfg802154_ops *ops, size_t priv_size) rdev->ops = ops; - mutex_lock(&wpan_phy_mutex); - rdev->wpan_phy.idx = wpan_phy_idx++; - if (unlikely(!wpan_phy_idx_valid(rdev->wpan_phy.idx))) { - wpan_phy_idx--; - mutex_unlock(&wpan_phy_mutex); + rdev->wpan_phy_idx = atomic_inc_return(&wpan_phy_counter); + + if (unlikely(rdev->wpan_phy_idx < 0)) { + /* ugh, wrapped! */ + atomic_dec(&wpan_phy_counter); kfree(rdev); - goto out; + return NULL; } - mutex_unlock(&wpan_phy_mutex); + + /* atomic_inc_return makes it start at 1, make it start at 0 */ + rdev->wpan_phy_idx--; mutex_init(&rdev->wpan_phy.pib_lock); device_initialize(&rdev->wpan_phy.dev); - dev_set_name(&rdev->wpan_phy.dev, "wpan-phy%d", rdev->wpan_phy.idx); + dev_set_name(&rdev->wpan_phy.dev, "wpan-phy%d", rdev->wpan_phy_idx); rdev->wpan_phy.dev.class = &wpan_phy_class; rdev->wpan_phy.dev.platform_data = rdev; return &rdev->wpan_phy; - -out: - return NULL; } EXPORT_SYMBOL(wpan_phy_alloc); diff --git a/net/ieee802154/core.h b/net/ieee802154/core.h index 1bc1725..fea60b3 100644 --- a/net/ieee802154/core.h +++ b/net/ieee802154/core.h @@ -6,6 +6,9 @@ struct cfg802154_registered_device { const struct cfg802154_ops *ops; + /* wpan_phy index, internal only */ + int wpan_phy_idx; + /* must be last because of the way we do wpan_phy_priv(), * and it should at least be aligned to NETDEV_ALIGN */ -- 2.1.3