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    SubjectRE: [PATCH 1/2] [SCSI] pm8001: Fix bogus interrupt state flag issue.
    Date
    Thanks for fix.
    Acked-by: Jack Wang <jack_wang@usish.com>
    >
    > In 'mpi_sata_completion'
    > the first call for 'spin_unlock_irqrestore()' is with flags=0,
    > which is as good as 'spin_unlock_irq()' ( unconditional interrupt
    > enabling). If intention of the developer is to enable the interrupt
    during
    > execution of ' mpi_sata_completion' , then the code changes in the patch
    > looks ok.
    >
    > If interrupt should not be enabled during execution of
    > 'mpi_sata_completion' then
    > we can use simple spin_lock and spin_unlock.
    >
    >
    > regards
    > santosh
    >
    >
    > On Sun, Feb 26, 2012 at 8:37 PM, Dan Carpenter <dan.carpenter@oracle.com>
    > wrote:
    > > On Sun, Feb 26, 2012 at 07:03:30PM +0530, santosh nayak wrote:
    > >> From: Santosh Nayak <santoshprasadnayak@gmail.com>
    > >>
    > >> Static checker is giving following warning:
    > >> " error: calling 'spin_unlock_irqrestore()' with bogus flags"
    > >>
    > >> The code flow is as shown below:
    > >> process_oq() --> process_one_iomb --> mpi_sata_completion
    > >>
    > >> In 'mpi_sata_completion'
    > >> the first call for 'spin_unlock_irqrestore()' is with flags=0,
    > >> which is as good as 'spin_unlock_irq()' ( unconditional interrupt
    > >> enabling).
    > >>
    > >> So for better performance 'spin_unlock_irqrestore()' can be replaced
    > >> with 'spin_unlock_irq()' and 'spin_lock_irqsave()' can be replaced by
    > >> 'spin_lock_irq()'.
    > >>
    > >
    > > process_oq() is called from the interrupt handler pm8001_chip_isr()
    > > with interrupts disabled.
    > >
    > > drivers/scsi/pm8001/pm8001_hwi.c
    > >  4301          spin_lock_irqsave(&pm8001_ha->lock, flags);
    > >  4302          pm8001_chip_interrupt_disable(pm8001_ha);
    > >  4303          process_oq(pm8001_ha);
    > >  4304          pm8001_chip_interrupt_enable(pm8001_ha);
    > >  4305          spin_unlock_irqrestore(&pm8001_ha->lock, flags);
    > >
    > > Probably we should just be doing a spin_lock() and spin_unlock()
    > > without re-enabling the IRQs.  Should we even be doing that in the
    > > irq handler anyway?
    > >
    > > regards,
    > > dan carpenter
    > >

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