1. 06 12月, 2006 2 次提交
  2. 05 10月, 2006 1 次提交
    • D
      IRQ: Maintain regs pointer globally rather than passing to IRQ handlers · 7d12e780
      David Howells 提交于
      Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
      of passing regs around manually through all ~1800 interrupt handlers in the
      Linux kernel.
      
      The regs pointer is used in few places, but it potentially costs both stack
      space and code to pass it around.  On the FRV arch, removing the regs parameter
      from all the genirq function results in a 20% speed up of the IRQ exit path
      (ie: from leaving timer_interrupt() to leaving do_IRQ()).
      
      Where appropriate, an arch may override the generic storage facility and do
      something different with the variable.  On FRV, for instance, the address is
      maintained in GR28 at all times inside the kernel as part of general exception
      handling.
      
      Having looked over the code, it appears that the parameter may be handed down
      through up to twenty or so layers of functions.  Consider a USB character
      device attached to a USB hub, attached to a USB controller that posts its
      interrupts through a cascaded auxiliary interrupt controller.  A character
      device driver may want to pass regs to the sysrq handler through the input
      layer which adds another few layers of parameter passing.
      
      I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
      main part of the code on FRV and i386, though I can't test most of the drivers.
      I've also done partial conversion for powerpc and MIPS - these at least compile
      with minimal configurations.
      
      This will affect all archs.  Mostly the changes should be relatively easy.
      Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
      
      	struct pt_regs *old_regs = set_irq_regs(regs);
      
      And put the old one back at the end:
      
      	set_irq_regs(old_regs);
      
      Don't pass regs through to generic_handle_irq() or __do_IRQ().
      
      In timer_interrupt(), this sort of change will be necessary:
      
      	-	update_process_times(user_mode(regs));
      	-	profile_tick(CPU_PROFILING, regs);
      	+	update_process_times(user_mode(get_irq_regs()));
      	+	profile_tick(CPU_PROFILING);
      
      I'd like to move update_process_times()'s use of get_irq_regs() into itself,
      except that i386, alone of the archs, uses something other than user_mode().
      
      Some notes on the interrupt handling in the drivers:
      
       (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
           the input_dev struct.
      
       (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
           something different depending on whether it's been supplied with a regs
           pointer or not.
      
       (*) Various IRQ handler function pointers have been moved to type
           irq_handler_t.
      Signed-Off-By: NDavid Howells <dhowells@redhat.com>
      (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
      7d12e780
  3. 02 10月, 2006 2 次提交
  4. 03 9月, 2006 3 次提交
    • J
      [SCSI] add failure return to scsi_init_shared_tag_map() · deb81d80
      James Bottomley 提交于
      And use it in the stex driver.
      Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>
      deb81d80
    • E
      [SCSI] stex: add shared tags from block · cf355883
      Ed Lin 提交于
      Use block shared tags entirely within the driver. In the case of
      shutdown, assume that there are no other outstanding commands, so tag
      0 is fine.
      Signed-off-by: NEd Lin <ed.lin@promise.com>
      Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>
      cf355883
    • J
      [SCSI] Add Promise SuperTrak driver · 5a25ba16
      Jeff Garzik 提交于
      Add Promise SuperTrak 'stex' driver, supporting SuperTrak
      EX8350/8300/16350/16300 controllers.  The controller's firmware accepts
      SCSI commands, handing them to the underlying RAID or JBOD disks.
      
      The driver consisted of the following cleanups and fixes, beyond its
      initial submission:
      
      Ed Lin:
            stex: cleanup and minor fixes
            stex: add new device ids
            stex: update internal copy code path
            stex: add hard reset function
            stex: adjust command timeout in slave_config routine
            stex: use more efficient method for unload/shutdown flush
      
      Jeff Garzik:
            [SCSI] Add Promise SuperTrak 'shasta' driver.
            Rename drivers/scsi/shasta.c to stex.c ("SuperTrak EX").
            [SCSI] stex: update with community comments from 'Promise SuperTrak' thread
            [SCSI] stex: Fix warning, trim trailing whitespace.
            [SCSI] stex: remove last remnants of "shasta" project code name
            [SCSI] stex: removed 6-byte command emulation
            [SCSI] stex: minor cleanups
            [SCSI] stex: minor fixes: irq flag, error return value
            [SCSI] stex: use dma_alloc_coherent()
      Signed-off-by: NJeff Garzik <jeff@garzik.org>
      Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>
      5a25ba16