Date: Mon, 24 Dec 2007 22:54:33 GMT From: Robert Watson <rwatson@FreeBSD.org> To: Perforce Change Reviews <perforce@freebsd.org> Subject: PERFORCE change 131556 for review Message-ID: <200712242254.lBOMsXO9042347@repoman.freebsd.org>
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http://perforce.freebsd.org/chv.cgi?CH=131556 Change 131556 by rwatson@rwatson_cinnamon on 2007/12/24 22:53:47 Remove memory barrier/atomic XXX's, since that is now addressed. Affected files ... .. //depot/projects/zcopybpf/src/sys/net/bpf_zerocopy.c#26 edit Differences ... ==== //depot/projects/zcopybpf/src/sys/net/bpf_zerocopy.c#26 (text+ko) ==== @@ -339,11 +339,6 @@ * Notification from the BPF framework that a buffer has moved into the held * slot on a descriptor. Zero-copy BPF will update the shared page to let * the user process know. - * - * XXXRW: Do we need to use a memory barrier, atomic operation, or the like - * to make sure that the generation update is the last write to make it out - * after any packet date so that user space sees the generation increase only - * at or after the last packet data change? */ void bpf_zerocopy_bufheld(struct bpf_d *d) @@ -364,8 +359,6 @@ * held position can be moved to the free position, which can be indicated by * the user process making their generation number equal to the kernel * generation number. - * - * XXXRW: Memory ordering also an issue here? */ int bpf_zerocopy_canfreebuf(struct bpf_d *d)
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