Date: Mon, 14 Aug 2017 13:15:13 +0000 (UTC) From: Hans Petter Selasky <hselasky@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r322501 - stable/9/sys/ofed/include/linux Message-ID: <201708141315.v7EDFDQa069269@repo.freebsd.org>
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Author: hselasky Date: Mon Aug 14 13:15:13 2017 New Revision: 322501 URL: https://svnweb.freebsd.org/changeset/base/322501 Log: MFC r292537 and r314878: Implement ACCESS_ONCE(), WRITE_ONCE() and READ_ONCE(). Sponsored by: Mellanox Technologies Modified: stable/9/sys/ofed/include/linux/compiler.h Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/ofed/include/linux/compiler.h ============================================================================== --- stable/9/sys/ofed/include/linux/compiler.h Mon Aug 14 12:59:14 2017 (r322500) +++ stable/9/sys/ofed/include/linux/compiler.h Mon Aug 14 13:15:13 2017 (r322501) @@ -63,4 +63,21 @@ #define uninitialized_var(x) x = x +#define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x)) + +#define WRITE_ONCE(x,v) do { \ + barrier(); \ + ACCESS_ONCE(x) = (v); \ + barrier(); \ +} while (0) + +#define READ_ONCE(x) ({ \ + __typeof(x) __var = ({ \ + barrier(); \ + ACCESS_ONCE(x); \ + }); \ + barrier(); \ + __var; \ +}) + #endif /* _LINUX_COMPILER_H_ */
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