On Wed, 2010-11-17 at 17:27 -0500, Christoph Hellwig wrote: > On Wed, Nov 17, 2010 at 02:18:42PM -0800, Nicholas A. Bellinger wrote: > > From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> > > > > This patch adds a IRQ_DISABLE_SCSI_QCMD() wrapper macro used by LLDs > > that can now run in host_lock less mode, but still need interrupts disabled > > using local_irq_save() before calling their lld_queuecommand() dispatcher. > > > > jgarzik says this method is in fact slower than doing a spin_lock_irqsave() on > > internal lib_lld_queuecommand() callers (as is done in libiscsi and libata) > > but is still needed by the majority of lock_less LLDs. > > It's not an overly helpful macro. There's no reason a driver should > ever disable irqs on it's own without actually taking a lock. Please > invest the additional couple of minutes and do a proper conversion. > Hmmm, this is following jgarzik's recommendation for LLDs that we could not immediately identify a internal spin_lock to disable interrupts upon. (eg: not libiscsi and libata). --nab -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
