From 8129ee164267dc030b8e1d541ee3643c0b9f2fa1 Mon Sep 17 00:00:00 2001 From: Frank Pavlic Date: Fri, 6 Jan 2006 00:19:20 -0800 Subject: [PATCH] s390: qdio V=V pass-through New feature V=V qdio pass-through. QDIO and HiperSockets processing in z/VM V=V guest environments (as well as V=R with z/VM running in LPAR mode) requires shadowing of all QDIO architecture queue elements. Especially the shadowing of SBALs and SLSBs structures in the hypervisor, and the need to issue SIGA SYNC operations to observe state changes, eventually causes significant CPU processing overhead in the hypervisor. The QDIO pass-through support for V=V guests avoids the shadowing of SBALs and SLSBs. This significantly reduces the hypervisor overhead for QDIO based I/O. Signed-off-by: Frank Pavlic Signed-off-by: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/Kconfig | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 477ac2758bd..1846fbfd6bf 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -240,8 +240,8 @@ config MACHCHK_WARNING config QDIO tristate "QDIO support" ---help--- - This driver provides the Queued Direct I/O base support for the - IBM S/390 (G5 and G6) and eServer zSeries (z800, z890, z900 and z990). + This driver provides the Queued Direct I/O base support for + IBM mainframes. For details please refer to the documentation provided by IBM at @@ -263,7 +263,8 @@ config QDIO_DEBUG bool "Extended debugging information" depends on QDIO help - Say Y here to get extended debugging output in /proc/s390dbf/qdio... + Say Y here to get extended debugging output in + /sys/kernel/debug/s390dbf/qdio... Warning: this option reduces the performance of the QDIO module. If unsure, say N. -- cgit v1.2.3-70-g09d2