On Fri, Sep 19, 2014 at 1:25 AM, Alexander Gordeev <[email protected]> wrote: > As described in AHCI v1.0 specification chapter 10.6.2.2 > "Multiple MSI Based Messages" generation of interrupts > is not controlled through the HOST_IRQ_STAT register. > > Considering MMIO access is expensive remove unnecessary > reading and writing of HOST_IRQ_STAT register. > > Further, serializing access to the host data is no longer > needed and the interrupt service routine can avoid competing > on the host lock. > > Signed-off-by: Alexander Gordeev <[email protected]> > Suggested-by: "Jiang, Dave" <[email protected]> > Cc: [email protected] > --- > drivers/ata/ahci.h | 1 + > drivers/ata/libahci.c | 54 > ++++++++------------------------------------------- > 2 files changed, 9 insertions(+), 46 deletions(-) > > diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h > index c12f590..b8e117a 100644 > --- a/drivers/ata/ahci.h > +++ b/drivers/ata/ahci.h > @@ -305,6 +305,7 @@ struct ahci_port_priv { > unsigned int ncq_saw_dmas:1; > unsigned int ncq_saw_sdb:1; > u32 intr_status; /* interrupts to handle */ > + spinlock_t intr_lock; /* protects intr_status */
Why introduce a new lock? Can't we switch to per-ata port locking rather than ata_host locking? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
