Path: csiph.com!eternal-september.org!feeder.eternal-september.org!news.unit0.net!news.panservice.it!diesel.cu.mi.it!bofh.it!news.nic.it!robomod From: Davidlohr Bueso Newsgroups: linux.kernel Subject: [PATCH] drivers/base: use READ_ONCE instead of deprecated ACCESS_ONCE Date: Sat, 19 Nov 2016 21:00:01 +0100 Message-ID: X-Mailer: git-send-email 2.6.6 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 51 Organization: linux.* mail to news gateway X-Original-Cc: linux-kernel@vger.kernel.org, Davidlohr Bueso , Davidlohr Bueso X-Original-Date: Sat, 19 Nov 2016 11:52:48 -0800 X-Original-Message-ID: <1479585168-7792-1-git-send-email-dave@stgolabs.net> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1526135 With the new standardized functions, we can replace all ACCESS_ONCE() calls across relevant drivers/base/. ACCESS_ONCE() does not work reliably on non-scalar types. For example gcc 4.6 and 4.7 might remove the volatile tag for such accesses during the SRA (scalar replacement of aggregates) step: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 Update the new calls regardless of if it is a scalar type, this is cleaner than having three alternatives. Signed-off-by: Davidlohr Bueso --- drivers/base/core.c | 2 +- drivers/base/power/runtime.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index ce057a568673..c0b3a2a03d72 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -101,7 +101,7 @@ const char *dev_driver_string(const struct device *dev) * so be careful about accessing it. dev->bus and dev->class should * never change once they are set, so they don't need special care. */ - drv = ACCESS_ONCE(dev->driver); + drv = READ_ONCE(dev->driver); return drv ? drv->name : (dev->bus ? dev->bus->name : (dev->class ? dev->class->name : "")); diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 60ebb04d8140..747c19286250 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -132,11 +132,11 @@ unsigned long pm_runtime_autosuspend_expiration(struct device *dev) if (!dev->power.use_autosuspend) goto out; - autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay); + autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); if (autosuspend_delay < 0) goto out; - last_busy = ACCESS_ONCE(dev->power.last_busy); + last_busy = READ_ONCE(dev->power.last_busy); elapsed = jiffies - last_busy; if (elapsed < 0) goto out; /* jiffies has wrapped around. */ -- 2.6.6