1. 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
  2. 04 10月, 2006 1 次提交
  3. 03 10月, 2006 1 次提交
  4. 01 10月, 2006 1 次提交
    • J
      [libata] pata_artop: kill gcc warning · 15a7c3bb
      Jeff Garzik 提交于
      gcc complains thusly:
      
      drivers/ata/pata_artop.c: In function ‘artop_init_one’:
      drivers/ata/pata_artop.c:429: warning: ‘info’ may be used uninitialized in this function
      
      While this warning is indeed bogus, even with improved static analysis
      and value range propagation, gcc will probably never be able to detect
      this.
      
      Add a BUG_ON() to trap invalid driver_data entries in the PCI table.
      Signed-off-by: NJeff Garzik <jeff@garzik.org>
      15a7c3bb
  5. 30 9月, 2006 1 次提交
  6. 29 9月, 2006 2 次提交
  7. 28 9月, 2006 5 次提交
  8. 27 9月, 2006 9 次提交
  9. 26 9月, 2006 2 次提交
  10. 25 9月, 2006 3 次提交
  11. 21 9月, 2006 1 次提交
  12. 19 9月, 2006 2 次提交
    • A
      [PATCH] libata: improve handling of diagostic fail (and hardware that misreports it) · 93590859
      Alan Cox 提交于
      Our ATA probe code checks that a device is not reporting a diagnostic
      failure during start up. Unfortunately at least one device seems to like
      doing this - the Gigabyte iRAM.
      
      This is only done for the master right now (which is fine for the iRAM
      as it is SATA), as with PATA some combinations of ATAPI device seem to
      fool the check into seeing a drive that isn't there if it is applied to
      the slave.
      Signed-off-by: NAlan Cox <alan@redhat.com>
      Signed-off-by: NJeff Garzik <jeff@garzik.org>
      93590859
    • T
      [PATCH] libata: fix non-uniform ports handling · fea63e38
      Tejun Heo 提交于
      Non-uniform ports handling got broken while updating libata to handle
      those in the same host.  Only separate irq for the non-uniform
      secondary port was implemented while all other fields (host flags,
      transfer mode...) of the secondary port simply shared those of the
      first.
      
      For ata_piix combined mode, which ATM is the only user of non-uniform
      ports, this causes the secondary port assume the wrong type.  This can
      cause PATA port to use SATA ops, which results in bogus check on PCS
      and detection failure.
      
      This patch adds ata_probe_ent->pinfo2 which points to optional
      port_info for the secondary port.  For the time being, this seems to
      be the simplest solution.  This workaround will be removed together
      with ata_probe_ent itself after init model is updated to allow more
      flexibility.
      Signed-off-by: NTejun Heo <htejun@gmail.com>
      Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
      Cc: Nelson A. de Oliveira <naoliv@gmail.com>
      Signed-off-by: NJeff Garzik <jeff@garzik.org>
      fea63e38
  13. 13 9月, 2006 3 次提交
  14. 06 9月, 2006 1 次提交
  15. 31 8月, 2006 2 次提交
  16. 30 8月, 2006 1 次提交
  17. 24 8月, 2006 4 次提交