RE: [PATCH 6/7] DCA: Add Direct Cache Access driver
David Miller [mailto:[EMAIL PROTECTED] > >> +static spinlock_t dca_lock; > ... >> +spin_lock_init(_lock); > >It's easier to use DEFINE_SPINLOCK(). > Thanks - I'll adjust that in a future patch. sln -- == Mr. Shannon Nelson LAN Access Division, Intel Corp. [EMAIL PROTECTED]I don't speak for Intel (503) 712-7659Parents can't afford to be squeamish. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
RE: [PATCH 6/7] DCA: Add Direct Cache Access driver
David Miller [mailto:[EMAIL PROTECTED] +static spinlock_t dca_lock; ... +spin_lock_init(dca_lock); It's easier to use DEFINE_SPINLOCK(). Thanks - I'll adjust that in a future patch. sln -- == Mr. Shannon Nelson LAN Access Division, Intel Corp. [EMAIL PROTECTED]I don't speak for Intel (503) 712-7659Parents can't afford to be squeamish. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 6/7] DCA: Add Direct Cache Access driver
From: Shannon Nelson <[EMAIL PROTECTED]> Date: Thu, 19 Jul 2007 17:45:17 -0700 > +static spinlock_t dca_lock; ... > + spin_lock_init(_lock); It's easier to use DEFINE_SPINLOCK(). - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 6/7] DCA: Add Direct Cache Access driver
Direct Cache Access (DCA) is a method for warming the CPU cache before data
is used, with the intent of lessening the impact of cache misses. This
patch adds a manager and interface for matching up client requests for DCA
services with devices that offer DCA services.
In order to use DCA, a module must do bus writes with the appropriate tag
bits set to trigger a cache read for a specific CPU. However, different
CPUs and chipsets can require different sets of tag bits, and the methods
for determining the correct bits may be simple hardcoding or may be a
hardware specific magic incantation. This interface is a way for DCA
clients to find the correct tag bits for the targeted CPU without needing
to know the specifics.
Signed-off-by: Shannon Nelson <[EMAIL PROTECTED]>
---
drivers/Kconfig |2 +
drivers/Makefile|1
drivers/dca/Kconfig | 11 +++
drivers/dca/Makefile|2 +
drivers/dca/dca-core.c | 170 +++
drivers/dca/dca-sysfs.c | 88
include/linux/dca.h | 47 +
7 files changed, 321 insertions(+), 0 deletions(-)
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 7916f4b..98b7e10 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -80,6 +80,8 @@ source "drivers/rtc/Kconfig"
source "drivers/dma/Kconfig"
+source "drivers/dca/Kconfig"
+
source "drivers/auxdisplay/Kconfig"
source "drivers/kvm/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 6d9d7fa..4e03de6 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -82,5 +82,6 @@ obj-$(CONFIG_CRYPTO) += crypto/
obj-$(CONFIG_SUPERH) += sh/
obj-$(CONFIG_GENERIC_TIME) += clocksource/
obj-$(CONFIG_DMA_ENGINE) += dma/
+obj-$(CONFIG_DCA) += dca/
obj-$(CONFIG_HID) += hid/
obj-$(CONFIG_PPC_PS3) += ps3/
diff --git a/drivers/dca/Kconfig b/drivers/dca/Kconfig
new file mode 100644
index 000..d901615
--- /dev/null
+++ b/drivers/dca/Kconfig
@@ -0,0 +1,11 @@
+#
+# DCA server configuration
+#
+
+config DCA
+ tristate "DCA support for clients and providers"
+ ---help---
+ This is a server to help modules that want to use Direct Cache
+ Access to find DCA providers that will supply correct CPU tags.
+ default m
+
diff --git a/drivers/dca/Makefile b/drivers/dca/Makefile
new file mode 100644
index 000..b2db56b
--- /dev/null
+++ b/drivers/dca/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_DCA) += dca.o
+dca-objs := dca-core.o dca-sysfs.o
diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c
new file mode 100644
index 000..864f469
--- /dev/null
+++ b/drivers/dca/dca-core.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called COPYING.
+ */
+
+/*
+ * This driver supports an interface for DCA clients and providers to meet.
+ */
+
+#include
+#include
+#include
+#include
+
+MODULE_LICENSE("GPL");
+
+/* For now we're assuming a single, global, DCA provider for the system. */
+
+static spinlock_t dca_lock;
+
+struct dca_provider *global_dca = NULL;
+
+int dca_add_requester(struct device *dev)
+{
+ int err, slot;
+
+ if (!global_dca)
+ return -ENODEV;
+
+ spin_lock(_lock);
+ slot = global_dca->ops->add_requester(global_dca, dev);
+ spin_unlock(_lock);
+ if (slot < 0)
+ return slot;
+
+ err = dca_sysfs_add_req(global_dca, dev, slot);
+ if (err) {
+ spin_lock(_lock);
+ global_dca->ops->remove_requester(global_dca, dev);
+ spin_unlock(_lock);
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(dca_add_requester);
+
+int dca_remove_requester(struct device *dev)
+{
+ int slot;
+ if (!global_dca)
+ return -ENODEV;
+
+ spin_lock(_lock);
+ slot = global_dca->ops->remove_requester(global_dca, dev);
+ spin_unlock(_lock);
+ if (slot < 0)
+ return slot;
+
+ dca_sysfs_remove_req(global_dca, slot);
+ return 0;
+}
+EXPORT_SYMBOL(dca_remove_requester);
+
+u8 dca_get_tag(int
[PATCH 6/7] DCA: Add Direct Cache Access driver
Direct Cache Access (DCA) is a method for warming the CPU cache before data
is used, with the intent of lessening the impact of cache misses. This
patch adds a manager and interface for matching up client requests for DCA
services with devices that offer DCA services.
In order to use DCA, a module must do bus writes with the appropriate tag
bits set to trigger a cache read for a specific CPU. However, different
CPUs and chipsets can require different sets of tag bits, and the methods
for determining the correct bits may be simple hardcoding or may be a
hardware specific magic incantation. This interface is a way for DCA
clients to find the correct tag bits for the targeted CPU without needing
to know the specifics.
Signed-off-by: Shannon Nelson [EMAIL PROTECTED]
---
drivers/Kconfig |2 +
drivers/Makefile|1
drivers/dca/Kconfig | 11 +++
drivers/dca/Makefile|2 +
drivers/dca/dca-core.c | 170 +++
drivers/dca/dca-sysfs.c | 88
include/linux/dca.h | 47 +
7 files changed, 321 insertions(+), 0 deletions(-)
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 7916f4b..98b7e10 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -80,6 +80,8 @@ source drivers/rtc/Kconfig
source drivers/dma/Kconfig
+source drivers/dca/Kconfig
+
source drivers/auxdisplay/Kconfig
source drivers/kvm/Kconfig
diff --git a/drivers/Makefile b/drivers/Makefile
index 6d9d7fa..4e03de6 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -82,5 +82,6 @@ obj-$(CONFIG_CRYPTO) += crypto/
obj-$(CONFIG_SUPERH) += sh/
obj-$(CONFIG_GENERIC_TIME) += clocksource/
obj-$(CONFIG_DMA_ENGINE) += dma/
+obj-$(CONFIG_DCA) += dca/
obj-$(CONFIG_HID) += hid/
obj-$(CONFIG_PPC_PS3) += ps3/
diff --git a/drivers/dca/Kconfig b/drivers/dca/Kconfig
new file mode 100644
index 000..d901615
--- /dev/null
+++ b/drivers/dca/Kconfig
@@ -0,0 +1,11 @@
+#
+# DCA server configuration
+#
+
+config DCA
+ tristate DCA support for clients and providers
+ ---help---
+ This is a server to help modules that want to use Direct Cache
+ Access to find DCA providers that will supply correct CPU tags.
+ default m
+
diff --git a/drivers/dca/Makefile b/drivers/dca/Makefile
new file mode 100644
index 000..b2db56b
--- /dev/null
+++ b/drivers/dca/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_DCA) += dca.o
+dca-objs := dca-core.o dca-sysfs.o
diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c
new file mode 100644
index 000..864f469
--- /dev/null
+++ b/drivers/dca/dca-core.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called COPYING.
+ */
+
+/*
+ * This driver supports an interface for DCA clients and providers to meet.
+ */
+
+#include linux/kernel.h
+#include linux/notifier.h
+#include linux/device.h
+#include linux/dca.h
+
+MODULE_LICENSE(GPL);
+
+/* For now we're assuming a single, global, DCA provider for the system. */
+
+static spinlock_t dca_lock;
+
+struct dca_provider *global_dca = NULL;
+
+int dca_add_requester(struct device *dev)
+{
+ int err, slot;
+
+ if (!global_dca)
+ return -ENODEV;
+
+ spin_lock(dca_lock);
+ slot = global_dca-ops-add_requester(global_dca, dev);
+ spin_unlock(dca_lock);
+ if (slot 0)
+ return slot;
+
+ err = dca_sysfs_add_req(global_dca, dev, slot);
+ if (err) {
+ spin_lock(dca_lock);
+ global_dca-ops-remove_requester(global_dca, dev);
+ spin_unlock(dca_lock);
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(dca_add_requester);
+
+int dca_remove_requester(struct device *dev)
+{
+ int slot;
+ if (!global_dca)
+ return -ENODEV;
+
+ spin_lock(dca_lock);
+ slot = global_dca-ops-remove_requester(global_dca, dev);
+ spin_unlock(dca_lock);
+ if (slot 0)
+ return slot;
+
+ dca_sysfs_remove_req(global_dca, slot);
+ return 0;
+}
Re: [PATCH 6/7] DCA: Add Direct Cache Access driver
From: Shannon Nelson [EMAIL PROTECTED] Date: Thu, 19 Jul 2007 17:45:17 -0700 +static spinlock_t dca_lock; ... + spin_lock_init(dca_lock); It's easier to use DEFINE_SPINLOCK(). - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
