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authorRandall Stewart <rrs@FreeBSD.org>2018-04-19 13:37:59 +0000
committerRandall Stewart <rrs@FreeBSD.org>2018-04-19 13:37:59 +0000
commit3ee9c3c4ebf1d1edb3337cef1a840bcfe383ceb8 (patch)
treefb6d95d8fcf8ce7161abc3c40ec4feb9a8da00fb /sys/sys/kern_prefetch.h
parentba85da072bd159bc97a38fde0f9757994b5bbb5b (diff)
downloadsrc-3ee9c3c4ebf1d1edb3337cef1a840bcfe383ceb8.tar.gz
src-3ee9c3c4ebf1d1edb3337cef1a840bcfe383ceb8.zip
This commit brings in the TCP high precision timer system (tcp_hpts).
It is the forerunner/foundational work of bringing in both Rack and BBR which use hpts for pacing out packets. The feature is optional and requires the TCPHPTS option to be enabled before the feature will be active. TCP modules that use it must assure that the base component is compile in the kernel in which they are loaded. MFC after: Never Sponsored by: Netflix Inc. Differential Revision: https://reviews.freebsd.org/D15020
Notes
Notes: svn path=/head/; revision=332770
Diffstat (limited to 'sys/sys/kern_prefetch.h')
-rw-r--r--sys/sys/kern_prefetch.h50
1 files changed, 50 insertions, 0 deletions
diff --git a/sys/sys/kern_prefetch.h b/sys/sys/kern_prefetch.h
new file mode 100644
index 000000000000..5acf06597498
--- /dev/null
+++ b/sys/sys/kern_prefetch.h
@@ -0,0 +1,50 @@
+#ifndef __kern_prefetch_h__
+/*-
+ * Copyright (c) 2016-8
+ * Netflix Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * __FBSDID("$FreeBSD$")
+ */
+#define __kern_prefetch_h__
+#ifdef _KERNEL
+#if defined(__amd64__)
+#include <vm/vm.h>
+#include <vm/vm_extern.h>
+#include <vm/vm_page.h>
+#include <vm/vm_map.h>
+#include <vm/pmap.h>
+#endif
+
+static __inline void
+kern_prefetch(const volatile void *addr, void* before)
+{
+#if defined(__amd64__)
+ __asm __volatile("prefetcht1 (%1)":"=rm"(*((int32_t *)before)):"r"(addr):);
+#else
+ __builtin_prefetch(addr);
+#endif
+}
+
+#endif
+#endif