1. 05 3月, 2008 1 次提交
  2. 19 2月, 2008 1 次提交
  3. 10 2月, 2008 1 次提交
    • C
      [S390] sclp_vt220: Fix vt220 initialization · 59eb1ca7
      Christian Borntraeger 提交于
      There are two problems in the vt220 intialization:
      
      o Currently the vt220 console looses early printk events until the
        the vt220 tty is registered.
      o console should work if tty_register fails
      
      sclp_vt220_con_init calls __sclp_vt220_init and register_console.
      It does not register the driver with the sclp core code via
      sclp_register. That results in an sclp_send_mask=0. Therefore,
      __sclp_vt220_emit will reject buffers with EIO. Unfortunately
      register_console will cause the printk buffer to be sent to the
      console and, therefore, every early message gets dropped. The
      sclp_send_mask is set later during boot, when sclp_vt220_tty_init
      calls sclp_register.
      
      The solution is to move the sclp_register call from sclp_vt220_tty_init
      to __sclp_vt220_init. This makes sure that the console is properly
      registered with the sclp subsystem before the first log buffer messages
      are passed to the vt220 console.
      
      We also adopt the cleanup on error to keep the console alive if
      tty_register fails.
      
      Thanks to Peter Oberparleiter and Heiko Carstens for review and ideas
      for improvement.
      Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      59eb1ca7
  4. 05 2月, 2008 1 次提交
    • C
      [S390] sclp_tty/sclp_vt220: Fix scheduling while atomic · e35e1fad
      Christian Borntraeger 提交于
      Under load the following bug message appeared while using sysrq-t:
      
      BUG: scheduling while atomic: bash/3662/0x00000004
      0000000000105b74 000000003ba17740 0000000000000002 0000000000000000
             000000003ba177e0 000000003ba17758 000000003ba17758 0000000000105bfe
             0000000000817ba8 000000003f2a5350 0000000000000000 0000000000000000
             000000003ba17740 000000000000000c 000000003ba17740 000000003ba177b0
             0000000000568630 0000000000105bfe 000000003ba17740 000000003ba17790
      Call Trace:
      ([<0000000000105b74>] show_trace+0x13c/0x158)
       [<0000000000105c58>] show_stack+0xc8/0xfc
       [<0000000000105cbc>] dump_stack+0x30/0x40
       [<000000000012a0c8>] __schedule_bug+0x84/0x94
       [<000000000056234e>] schedule+0x5ea/0x970
       [<0000000000477cd2>] __sclp_vt220_write+0x1f6/0x3ec
       [<0000000000477f00>] sclp_vt220_con_write+0x38/0x48
       [<0000000000130b4a>] __call_console_drivers+0xbe/0xd8
       [<0000000000130bf0>] _call_console_drivers+0x8c/0xd0
       [<0000000000130eea>] release_console_sem+0x1a6/0x2fc
       [<0000000000131786>] vprintk+0x262/0x480
       [<00000000001319fa>] printk+0x56/0x68
       [<0000000000125aaa>] print_cfs_rq+0x45e/0x4a4
       [<000000000012614e>] sched_debug_show+0x65e/0xee8
       [<000000000012a8fc>] show_state_filter+0x1cc/0x1f0
       [<000000000044d39c>] sysrq_handle_showstate+0x2c/0x3c
       [<000000000044d1fe>] __handle_sysrq+0xae/0x18c
       [<00000000002001f2>] write_sysrq_trigger+0x8a/0x90
       [<00000000001f7862>] proc_reg_write+0x9a/0xc4
       [<00000000001a83d4>] vfs_write+0xb8/0x174
       [<00000000001a8b88>] sys_write+0x58/0x8c
       [<0000000000112e7c>] sysc_noemu+0x10/0x16
       [<0000020000116f68>] 0x20000116f68
      
      The problem seems to be, that with a full console buffer, release_console_sem
      disables interrupts with spin_lock_irqsave and then calls the console function
      without enabling interrupts. __sclp_vt220_write checks for in_interrupt, to
      decide if it can schedule. It should check for in_atomic instead.
      
      The same is true for sclp_tty.c.
      Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      e35e1fad
  5. 27 7月, 2007 2 次提交
  6. 27 4月, 2007 1 次提交
  7. 15 2月, 2007 1 次提交
    • T
      [PATCH] remove many unneeded #includes of sched.h · cd354f1a
      Tim Schmielau 提交于
      After Al Viro (finally) succeeded in removing the sched.h #include in module.h
      recently, it makes sense again to remove other superfluous sched.h includes.
      There are quite a lot of files which include it but don't actually need
      anything defined in there.  Presumably these includes were once needed for
      macros that used to live in sched.h, but moved to other header files in the
      course of cleaning it up.
      
      To ease the pain, this time I did not fiddle with any header files and only
      removed #includes from .c-files, which tend to cause less trouble.
      
      Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
      arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
      allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
      configs in arch/arm/configs on arm.  I also checked that no new warnings were
      introduced by the patch (actually, some warnings are removed that were emitted
      by unnecessarily included header files).
      Signed-off-by: NTim Schmielau <tim@physik3.uni-rostock.de>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cd354f1a
  8. 06 2月, 2007 2 次提交
  9. 02 10月, 2006 1 次提交
    • J
      [PATCH] const struct tty_operations · b68e31d0
      Jeff Dike 提交于
      As part of an SMP cleanliness pass over UML, I consted a bunch of
      structures in order to not have to document their locking.  One of these
      structures was a struct tty_operations.  In order to const it in UML
      without introducing compiler complaints, the declaration of
      tty_set_operations needs to be changed, and then all of its callers need to
      be fixed.
      
      This patch declares all struct tty_operations in the tree as const.  In all
      cases, they are static and used only as input to tty_set_operations.  As an
      extra check, I ran an i386 allyesconfig build which produced no extra
      warnings.
      
      53 drivers are affected.  I checked the history of a bunch of them, and in
      most cases, there have been only a handful of maintenance changes in the
      last six months.  serial_core.c was the busiest one that I looked at.
      Signed-off-by: NJeff Dike <jdike@addtoit.com>
      Acked-by: NAlan Cox <alan@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b68e31d0
  10. 01 7月, 2006 1 次提交
  11. 11 1月, 2006 1 次提交
    • A
      [PATCH] TTY layer buffering revamp · 33f0f88f
      Alan Cox 提交于
      The API and code have been through various bits of initial review by
      serial driver people but they definitely need to live somewhere for a
      while so the unconverted drivers can get knocked into shape, existing
      drivers that have been updated can be better tuned and bugs whacked out.
      
      This replaces the tty flip buffers with kmalloc objects in rings. In the
      normal situation for an IRQ driven serial port at typical speeds the
      behaviour is pretty much the same, two buffers end up allocated and the
      kernel cycles between them as before.
      
      When there are delays or at high speed we now behave far better as the
      buffer pool can grow a bit rather than lose characters. This also means
      that we can operate at higher speeds reliably.
      
      For drivers that receive characters in blocks (DMA based, USB and
      especially virtualisation) the layer allows a lot of driver specific
      code that works around the tty layer with private secondary queues to be
      removed. The IBM folks need this sort of layer, the smart serial port
      people do, the virtualisers do (because a virtualised tty typically
      operates at infinite speed rather than emulating 9600 baud).
      
      Finally many drivers had invalid and unsafe attempts to avoid buffer
      overflows by directly invoking tty methods extracted out of the innards
      of work queue structs. These are no longer needed and all go away. That
      fixes various random hangs with serial ports on overflow.
      
      The other change in here is to optimise the receive_room path that is
      used by some callers. It turns out that only one ldisc uses receive room
      except asa constant and it updates it far far less than the value is
      read. We thus make it a variable not a function call.
      
      I expect the code to contain bugs due to the size alone but I'll be
      watching and squashing them and feeding out new patches as it goes.
      
      Because the buffers now dynamically expand you should only run out of
      buffering when the kernel runs out of memory for real.  That means a lot of
      the horrible hacks high performance drivers used to do just aren't needed any
      more.
      
      Description:
      
      tty_insert_flip_char is an old API and continues to work as before, as does
      tty_flip_buffer_push() [this is why many drivers dont need modification].  It
      does now also return the number of chars inserted
      
      There are also
      
      tty_buffer_request_room(tty, len)
      
      which asks for a buffer block of the length requested and returns the space
      found.  This improves efficiency with hardware that knows how much to
      transfer.
      
      and tty_insert_flip_string_flags(tty, str, flags, len)
      
      to insert a string of characters and flags
      
      For a smart interface the usual code is
      
          len = tty_request_buffer_room(tty, amount_hardware_says);
          tty_insert_flip_string(tty, buffer_from_card, len);
      
      More description!
      
      At the moment tty buffers are attached directly to the tty.  This is causing a
      lot of the problems related to tty layer locking, also problems at high speed
      and also with bursty data (such as occurs in virtualised environments)
      
      I'm working on ripping out the flip buffers and replacing them with a pool of
      dynamically allocated buffers.  This allows both for old style "byte I/O"
      devices and also helps virtualisation and smart devices where large blocks of
      data suddenely materialise and need storing.
      
      So far so good.  Lots of drivers reference tty->flip.*.  Several of them also
      call directly and unsafely into function pointers it provides.  This will all
      break.  Most drivers can use tty_insert_flip_char which can be kept as an API
      but others need more.
      
      At the moment I've added the following interfaces, if people think more will
      be needed now is a good time to say
      
       int tty_buffer_request_room(tty, size)
      
      Try and ensure at least size bytes are available, returns actual room (may be
      zero).  At the moment it just uses the flipbuf space but that will change.
      Repeated calls without characters being added are not cumulative.  (ie if you
      call it with 1, 1, 1, and then 4 you'll have four characters of space.  The
      other functions will also try and grow buffers in future but this will be a
      more efficient way when you know block sizes.
      
       int tty_insert_flip_char(tty, ch, flag)
      
      As before insert a character if there is room.  Now returns 1 for success, 0
      for failure.
      
       int tty_insert_flip_string(tty, str, len)
      
      Insert a block of non error characters.  Returns the number inserted.
      
       int tty_prepare_flip_string(tty, strptr, len)
      
      Adjust the buffer to allow len characters to be added.  Returns a buffer
      pointer in strptr and the length available.  This allows for hardware that
      needs to use functions like insl or mencpy_fromio.
      Signed-off-by: NAlan Cox <alan@redhat.com>
      Cc: Paul Fulghum <paulkf@microgate.com>
      Signed-off-by: NHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NJeff Dike <jdike@addtoit.com>
      Signed-off-by: NJohn Hawkes <hawkes@sgi.com>
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: NAdrian Bunk <bunk@stusta.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      33f0f88f
  12. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds 提交于
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4