01 May, 2011

1 commit


17 Nov, 2010

1 commit

  • Move the mid-layer's ->queuecommand() invocation from being locked
    with the host lock to being unlocked to facilitate speeding up the
    critical path for drivers who don't need this lock taken anyway.

    The patch below presents a simple SCSI host lock push-down as an
    equivalent transformation. No locking or other behavior should change
    with this patch. All existing bugs and locking orders are preserved.

    Additionally, add one parameter to queuecommand,
    struct Scsi_Host *
    and remove one parameter from queuecommand,
    void (*done)(struct scsi_cmnd *)

    Scsi_Host* is a convenient pointer that most host drivers need anyway,
    and 'done' is redundant to struct scsi_cmnd->scsi_done.

    Minimal code disturbance was attempted with this change. Most drivers
    needed only two one-line modifications for their host lock push-down.

    Signed-off-by: Jeff Garzik
    Acked-by: James Bottomley
    Signed-off-by: Linus Torvalds

    Jeff Garzik
     

30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

30 Dec, 2008

1 commit


04 Oct, 2008

1 commit

  • Multiline kernel messages should contain a priority in every line,
    besides, some log daemons represent a tabulator as "^I", fix both these
    issues.

    Signed-off-by: Nick Warne
    Signed-off-by: Guennadi Liakhovetski
    Signed-off-by: James Bottomley

    Nick Warne
     

27 Jul, 2008

1 commit


24 Jan, 2008

1 commit


23 Oct, 2007

1 commit


13 Oct, 2007

1 commit

  • The pid field is a duplicate of the serial_number field and has been
    scheduled for removal for a long time. A few drivers were still using
    it, so just change them to use serial_number instead.

    Signed-off-by: Matthew Wilcox
    Signed-off-by: James Bottomley

    Matthew Wilcox
     

20 Jul, 2007

1 commit

  • Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).

    Here is a short excerpt of the semantic patch performing
    this transformation:

    @@
    type T2;
    expression x;
    identifier f,fld;
    expression E;
    expression E1,E2;
    expression e1,e2,e3,y;
    statement S;
    @@

    x =
    - kmalloc
    + kzalloc
    (E1,E2)
    ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
    - memset((T2)x,0,E1);

    @@
    expression E1,E2,E3;
    @@

    - kzalloc(E1 * E2,E3)
    + kcalloc(E1,E2,E3)

    [akpm@linux-foundation.org: get kcalloc args the right way around]
    Signed-off-by: Yoann Padioleau
    Cc: Richard Henderson
    Cc: Ivan Kokshaysky
    Acked-by: Russell King
    Cc: Bryan Wu
    Acked-by: Jiri Slaby
    Cc: Dave Airlie
    Acked-by: Roland Dreier
    Cc: Jiri Kosina
    Acked-by: Dmitry Torokhov
    Cc: Benjamin Herrenschmidt
    Acked-by: Mauro Carvalho Chehab
    Acked-by: Pierre Ossman
    Cc: Jeff Garzik
    Cc: "David S. Miller"
    Acked-by: Greg KH
    Cc: James Bottomley
    Cc: "Antonino A. Daplas"
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Yoann Padioleau
     

15 Jul, 2007

1 commit


20 Jun, 2007

1 commit


28 May, 2007

1 commit


06 May, 2007

4 commits


15 Feb, 2007

1 commit

  • 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: Tim Schmielau
    Acked-by: Russell King
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Tim Schmielau
     

26 Oct, 2006

1 commit


07 Oct, 2006

1 commit

  • - Eliminate casts to/from void*

    - Eliminate checks for conditions that never occur. These typically
    fall into two classes:

    1) Checking for 'dev_id == NULL', then it is never called with
    NULL as an argument.

    2) Checking for invalid irq number, when the only caller (the
    system) guarantees the irq handler is called with the proper
    'irq' number argument.

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     

05 Oct, 2006

1 commit

  • 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: David Howells
    (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

    David Howells
     

03 Oct, 2006

1 commit

  • following an email from John Adams to me with a patch
    to enable tmscsim to use blocks up to 1MB and a discussion on linux-scsi,
    below is a patch to enable clustering for tmscsim. I made it switchable
    with a module parameter, with default "enable" - in case somebody gets
    problems with it. Unfortunately, I was not able to check if this alone
    lets you use any bigger blocks with a tape, as my tape seems to only
    support 1 block size - only "mt setblk 1" is successful, any other value
    fails. OTOH, testing on a P-133 showed that enabling clustering alone
    improves throughput by 10% and reduces CPU load by another 10%, so, seems
    a worthy thing to do. As for setting max_sectors, that might become a
    separate patch...

    Signed-off-by: James Bottomley

    Guennadi Liakhovetski
     

03 Jul, 2006

1 commit


01 Jul, 2006

1 commit


29 Oct, 2005

1 commit


21 Sep, 2005

1 commit


18 Jun, 2005

1 commit


17 Apr, 2005

1 commit

  • 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!

    Linus Torvalds