On Wed, 2021-07-21 at 20:34 -0700, Bart Van Assche wrote: > Use a spinlock to protect hba->outstanding_reqs instead of using > atomic > > operations to update this member variable. > > > > This patch is a performance improvement because it reduces the number > of > > atomic operations in the hot path (test_and_clear_bit()) and because > it > > reduces the lock contention on the SCSI host lock. On my test setup > this > > patch improves IOPS by about 1%. > > > > Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> > > Cc: Stanley Chu <stanley.chu@xxxxxxxxxxxx> > > Cc: Can Guo <cang@xxxxxxxxxxxxxx> > > Cc: Asutosh Das <asutoshd@xxxxxxxxxxxxxx> > > Cc: Avri Altman <avri.altman@xxxxxxx> > > Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>
