Messages in this thread | | | Date | Mon, 03 Dec 2012 05:05:30 -0500 | From | Jeff Garzik <> | Subject | Re: [PATCH v4 -tip 3/3] AHCI: Support multiple MSIs |
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On 11/19/2012 10:02 AM, Alexander Gordeev wrote: > Take advantage of multiple MSIs implementation on x86 - on systems with > IRQ remapping AHCI ports not only get assigned separate MSI vectors - > but also separate IRQs. As result, interrupts generated by different > ports could be serviced on different CPUs rather than on a single one. > > In cases when number of allocated MSIs is less than requested the Sharing > Last MSI mode does not get used, no matter implemented in hardware or not. > Instead, the driver assumes the advantage of multiple MSIs is negated and > falls back to the single MSI mode as if MRSM bit was set (some Intel chips > implement this strategy anyway - MRSM bit gets set even if the number of > allocated MSIs exceeds the number of implemented ports). > > Signed-off-by: Alexander Gordeev <agordeev@redhat.com> > --- > drivers/ata/ahci.c | 93 +++++++++++++++++++++++++++++++++++++-- > drivers/ata/ahci.h | 6 +++ > drivers/ata/libahci.c | 118 ++++++++++++++++++++++++++++++++++++++++++++++--- > 3 files changed, 207 insertions(+), 10 deletions(-)
Acked-by: Jeff Garzik <jgarzik@redhat.com>
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