01 Nov, 2011

1 commit


01 Jul, 2011

2 commits

  • The perf_event overflow handler does not receive any caller-derived
    argument, so many callers need to resort to looking up the perf_event
    in their local data structure. This is ugly and doesn't scale if a
    single callback services many perf_events.

    Fix by adding a context parameter to perf_event_create_kernel_counter()
    (and derived hardware breakpoints APIs) and storing it in the perf_event.
    The field can be accessed from the callback as event->overflow_handler_context.
    All callers are updated.

    Signed-off-by: Avi Kivity
    Signed-off-by: Peter Zijlstra
    Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com
    Signed-off-by: Ingo Molnar

    Avi Kivity
     
  • The nmi parameter indicated if we could do wakeups from the current
    context, if not, we would set some state and self-IPI and let the
    resulting interrupt do the wakeup.

    For the various event classes:

    - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
    the PMI-tail (ARM etc.)
    - tracepoint: nmi=0; since tracepoint could be from NMI context.
    - software: nmi=[0,1]; some, like the schedule thing cannot
    perform wakeups, and hence need 0.

    As one can see, there is very little nmi=1 usage, and the down-side of
    not using it is that on some platforms some software events can have a
    jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).

    The up-side however is that we can remove the nmi parameter and save a
    bunch of conditionals in fast paths.

    Signed-off-by: Peter Zijlstra
    Cc: Michael Cree
    Cc: Will Deacon
    Cc: Deng-Cheng Zhu
    Cc: Anton Blanchard
    Cc: Eric B Munson
    Cc: Heiko Carstens
    Cc: Paul Mundt
    Cc: David S. Miller
    Cc: Frederic Weisbecker
    Cc: Jason Wessel
    Cc: Don Zickus
    Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     

23 May, 2011

1 commit


21 Apr, 2011

1 commit

  • samples/hid-example.o needs some Kconfig and Makefile additions in order
    to build. It should use headers from the build tree, so use
    HEADERS_CHECK to require that those header files be present.

    Change the kconfig symbol from tristate to bool since userspace cannot be
    built as loadable modules.

    However, I don't understand why the userspace header files are not present
    as reported in Andrew's build log, since it builds OK on x86_64 without
    any of these changes.

    Signed-off-by: Randy Dunlap
    Cc: Alan Ott
    Cc: Jiri Kosina
    Signed-off-by: Andrew Morton
    Signed-off-by: Jiri Kosina

    Randy Dunlap
     

09 Apr, 2011

1 commit

  • On systems where userspace doesn't have new hidraw.h populated to
    /usr/include, the hidraw sample won't compile as it's missing the new
    ioctl defitions.

    Introduce temporary ugly workaround to define the ioctls "manually"
    in such cases, just to avoid miscompilation in allmodconfig cases.

    Reported-by: Stephen Rothwell
    Signed-off-by: Jiri Kosina

    Jiri Kosina
     

31 Mar, 2011

1 commit


22 Mar, 2011

1 commit


30 Oct, 2010

1 commit


23 Oct, 2010

1 commit

  • * 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
    vfs: make no_llseek the default
    vfs: don't use BKL in default_llseek
    llseek: automatically add .llseek fop
    libfs: use generic_file_llseek for simple_attr
    mac80211: disallow seeks in minstrel debug code
    lirc: make chardev nonseekable
    viotape: use noop_llseek
    raw: use explicit llseek file operations
    ibmasmfs: use generic_file_llseek
    spufs: use llseek in all file operations
    arm/omap: use generic_file_llseek in iommu_debug
    lkdtm: use generic_file_llseek in debugfs
    net/wireless: use generic_file_llseek in debugfs
    drm: use noop_llseek

    Linus Torvalds
     

15 Oct, 2010

1 commit

  • All file_operations should get a .llseek operation so we can make
    nonseekable_open the default for future file operations without a
    .llseek pointer.

    The three cases that we can automatically detect are no_llseek, seq_lseek
    and default_llseek. For cases where we can we can automatically prove that
    the file offset is always ignored, we use noop_llseek, which maintains
    the current behavior of not returning an error from a seek.

    New drivers should normally not use noop_llseek but instead use no_llseek
    and call nonseekable_open at open time. Existing drivers can be converted
    to do the same when the maintainer knows for certain that no user code
    relies on calling seek on the device file.

    The generated code is often incorrectly indented and right now contains
    comments that clarify for each added line why a specific variant was
    chosen. In the version that gets submitted upstream, the comments will
    be gone and I will manually fix the indentation, because there does not
    seem to be a way to do that using coccinelle.

    Some amount of new code is currently sitting in linux-next that should get
    the same modifications, which I will do at the end of the merge window.

    Many thanks to Julia Lawall for helping me learn to write a semantic
    patch that does all this.

    ===== begin semantic patch =====
    // This adds an llseek= method to all file operations,
    // as a preparation for making no_llseek the default.
    //
    // The rules are
    // - use no_llseek explicitly if we do nonseekable_open
    // - use seq_lseek for sequential files
    // - use default_llseek if we know we access f_pos
    // - use noop_llseek if we know we don't access f_pos,
    // but we still want to allow users to call lseek
    //
    @ open1 exists @
    identifier nested_open;
    @@
    nested_open(...)
    {

    }

    @ open exists@
    identifier open_f;
    identifier i, f;
    identifier open1.nested_open;
    @@
    int open_f(struct inode *i, struct file *f)
    {

    }

    @ read disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {

    }

    @ read_no_fpos disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ write @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {

    }

    @ write_no_fpos @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ fops0 @
    identifier fops;
    @@
    struct file_operations fops = {
    ...
    };

    @ has_llseek depends on fops0 @
    identifier fops0.fops;
    identifier llseek_f;
    @@
    struct file_operations fops = {
    ...
    .llseek = llseek_f,
    ...
    };

    @ has_read depends on fops0 @
    identifier fops0.fops;
    identifier read_f;
    @@
    struct file_operations fops = {
    ...
    .read = read_f,
    ...
    };

    @ has_write depends on fops0 @
    identifier fops0.fops;
    identifier write_f;
    @@
    struct file_operations fops = {
    ...
    .write = write_f,
    ...
    };

    @ has_open depends on fops0 @
    identifier fops0.fops;
    identifier open_f;
    @@
    struct file_operations fops = {
    ...
    .open = open_f,
    ...
    };

    // use no_llseek if we call nonseekable_open
    ////////////////////////////////////////////
    @ nonseekable1 depends on !has_llseek && has_open @
    identifier fops0.fops;
    identifier nso ~= "nonseekable_open";
    @@
    struct file_operations fops = {
    ... .open = nso, ...
    +.llseek = no_llseek, /* nonseekable */
    };

    @ nonseekable2 depends on !has_llseek @
    identifier fops0.fops;
    identifier open.open_f;
    @@
    struct file_operations fops = {
    ... .open = open_f, ...
    +.llseek = no_llseek, /* open uses nonseekable */
    };

    // use seq_lseek for sequential files
    /////////////////////////////////////
    @ seq depends on !has_llseek @
    identifier fops0.fops;
    identifier sr ~= "seq_read";
    @@
    struct file_operations fops = {
    ... .read = sr, ...
    +.llseek = seq_lseek, /* we have seq_read */
    };

    // use default_llseek if there is a readdir
    ///////////////////////////////////////////
    @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier readdir_e;
    @@
    // any other fop is used that changes pos
    struct file_operations fops = {
    ... .readdir = readdir_e, ...
    +.llseek = default_llseek, /* readdir is present */
    };

    // use default_llseek if at least one of read/write touches f_pos
    /////////////////////////////////////////////////////////////////
    @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read.read_f;
    @@
    // read fops use offset
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = default_llseek, /* read accesses f_pos */
    };

    @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ... .write = write_f, ...
    + .llseek = default_llseek, /* write accesses f_pos */
    };

    // Use noop_llseek if neither read nor write accesses f_pos
    ///////////////////////////////////////////////////////////

    @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    identifier write_no_fpos.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ...
    .write = write_f,
    .read = read_f,
    ...
    +.llseek = noop_llseek, /* read and write both use no f_pos */
    };

    @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write_no_fpos.write_f;
    @@
    struct file_operations fops = {
    ... .write = write_f, ...
    +.llseek = noop_llseek, /* write uses no f_pos */
    };

    @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    @@
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = noop_llseek, /* read uses no f_pos */
    };

    @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    @@
    struct file_operations fops = {
    ...
    +.llseek = noop_llseek, /* no read or write fn */
    };
    ===== End semantic patch =====

    Signed-off-by: Arnd Bergmann
    Cc: Julia Lawall
    Cc: Christoph Hellwig

    Arnd Bergmann
     

02 Oct, 2010

1 commit

  • The kfifo_dma family of functions use sg_mark_end() on the last element in
    their scatterlist. This forces use of a fresh scatterlist for each DMA
    operation, which makes recycling a single scatterlist impossible.

    Change the behavior of the kfifo_dma functions to match the usage of the
    dma_map_sg function. This means that users must respect the returned
    nents value. The sample code is updated to reflect the change.

    This bug is trivial to cause: call kfifo_dma_in_prepare() such that it
    prepares a scatterlist with a single entry comprising the whole fifo.
    This is the case when you map the entirety of a newly created empty fifo.
    This causes the setup_sgl() function to mark the first scatterlist entry
    as the end of the chain, no matter what comes after it.

    Afterwards, add and remove some data from the fifo such that another call
    to kfifo_dma_in_prepare() will create two scatterlist entries. It returns
    nents=2. However, due to the previous sg_mark_end() call, sg_is_last()
    will now return true for the first scatterlist element. This causes the
    sample code to print a single scatterlist element when it should print
    two.

    By removing the call to sg_mark_end(), we make the API as similar as
    possible to the DMA mapping API. All users are required to respect the
    returned nents.

    Signed-off-by: Ira W. Snyder
    Cc: Stefani Seibold
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ira W. Snyder
     

21 Aug, 2010

5 commits

  • Provide a check in all the kfifo examples to validate the correct
    execution of each testcase.

    Signed-off-by: Andrea Righi
    Acked-by: Stefani Seibold
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     
  • We use a dynamically allocated kfifo in the dma example, so we need to
    free it when unloading the module.

    Signed-off-by: Andrea Righi
    Acked-by: Stefani Seibold
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     
  • The scatterlist is used uninitialized in kfifo_dma_in_prepare(). This
    triggers the following bug if CONFIG_DEBUG_SG=y:

    ------------[ cut here ]------------
    kernel BUG at include/linux/scatterlist.h:65!
    invalid opcode: 0000 [#1] PREEMPT SMP
    ...
    Call Trace:
    [] setup_sgl+0x6b/0xe0
    [] ? example_init+0x0/0x265 [dma_example]
    [] __kfifo_dma_in_prepare+0x21/0x30
    [] example_init+0x124/0x265 [dma_example]
    [] ? trace_module_notify+0x25/0x370
    [] ? free_pages_prepare+0x11e/0x1e0
    [] ? get_parent_ip+0x11/0x50
    [] ? trace_module_notify+0x25/0x370
    [] ? trace_hardirqs_on+0xd/0x10
    [] ? mutex_unlock+0xe/0x10
    [] ? trace_module_notify+0x41/0x370
    [] ? __blocking_notifier_call_chain+0x45/0x80
    [] ? vfree+0x2a/0x30
    [] ? up_read+0x23/0x40
    [] ? __blocking_notifier_call_chain+0x65/0x80
    [] do_one_initcall+0x43/0x180
    [] sys_init_module+0xba/0x200
    [] system_call_fastpath+0x16/0x1b
    RIP [] setup_sgl_buf+0x1a1/0x1b0
    RSP
    ---[ end trace a72b979fd3c1d3a5 ]---

    Add the proper initialization to avoid the bug.

    Signed-off-by: Andrea Righi
    Acked-by: Stefani Seibold
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     
  • Provide a static array of expected items that kfifo should contain at the
    end of the test to validate it.

    Signed-off-by: Andrea Righi
    Cc: Stefani Seibold
    Cc: Greg KH
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     
  • Add a testcase for kfifo_skip() to the byte stream fifo example.

    Signed-off-by: Andrea Righi
    Cc: Greg KH
    Acked-by: Stefani Seibold
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     

11 Aug, 2010

1 commit

  • Add four examples to the kernel sample directory.

    It shows how to handle:
    - a byte stream fifo
    - a integer type fifo
    - a dynamic record sized fifo
    - the fifo DMA functions

    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: Stefani Seibold
    Cc: Greg KH
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Stefani Seibold
     

05 Aug, 2010

1 commit

  • This KProbes example is a little useless if it doesn't print anything.
    For MIPS print similar messages to those produced on x86 and PPC.

    Signed-off-by: David Daney
    To: linux-mips@linux-mips.org
    To: ananth@in.ibm.com
    To: anil.s.keshavamurthy@intel.com
    To: davem@davemloft.net
    To: masami.hiramatsu.pt@hitachi.com
    Cc: linux-kernel@vger.kernel.org
    Cc: hschauhan@nulltrace.org
    Patchwork: https://patchwork.linux-mips.org/patch/1528/
    Signed-off-by: Ralf Baechle

    David Daney
     

14 May, 2010

1 commit

  • This patch adds data to be passed to tracepoint callbacks.

    The created functions from DECLARE_TRACE() now need a mandatory data
    parameter. For example:

    DECLARE_TRACE(mytracepoint, int value, value)

    Will create the register function:

    int register_trace_mytracepoint((void(*)(void *data, int value))probe,
    void *data);

    As the first argument, all callbacks (probes) must take a (void *data)
    parameter. So a callback for the above tracepoint will look like:

    void myprobe(void *data, int value)
    {
    }

    The callback may choose to ignore the data parameter.

    This change allows callbacks to register a private data pointer along
    with the function probe.

    void mycallback(void *data, int value);

    register_trace_mytracepoint(mycallback, mydata);

    Then the mycallback() will receive the "mydata" as the first parameter
    before the args.

    A more detailed example:

    DECLARE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status));

    /* In the C file */

    DEFINE_TRACE(mytracepoint, TP_PROTO(int status), TP_ARGS(status));

    [...]

    trace_mytracepoint(status);

    /* In a file registering this tracepoint */

    int my_callback(void *data, int status)
    {
    struct my_struct my_data = data;
    [...]
    }

    [...]
    my_data = kmalloc(sizeof(*my_data), GFP_KERNEL);
    init_my_data(my_data);
    register_trace_mytracepoint(my_callback, my_data);

    The same callback can also be registered to the same tracepoint as long
    as the data registered is different. Note, the data must also be used
    to unregister the callback:

    unregister_trace_mytracepoint(my_callback, my_data);

    Because of the data parameter, tracepoints declared this way can not have
    no args. That is:

    DECLARE_TRACE(mytracepoint, TP_PROTO(void), TP_ARGS());

    will cause an error.

    If no arguments are needed, a new macro can be used instead:

    DECLARE_TRACE_NOARGS(mytracepoint);

    Since there are no arguments, the proto and args fields are left out.

    This is part of a series to make the tracepoint footprint smaller:

    text data bss dec hex filename
    4913961 1088356 861512 6863829 68bbd5 vmlinux.orig
    4914025 1088868 861512 6864405 68be15 vmlinux.class
    4918492 1084612 861512 6864616 68bee8 vmlinux.tracepoint

    Again, this patch also increases the size of the kernel, but
    lays the ground work for decreasing it.

    v5: Fixed net/core/drop_monitor.c to handle these updates.

    v4: Moved the DECLARE_TRACE() DECLARE_TRACE_NOARGS out of the
    #ifdef CONFIG_TRACE_POINTS, since the two are the same in both
    cases. The __DECLARE_TRACE() is what changes.
    Thanks to Frederic Weisbecker for pointing this out.

    v3: Made all register_* functions require data to be passed and
    all callbacks to take a void * parameter as its first argument.
    This makes the calling functions comply with C standards.

    Also added more comments to the modifications of DECLARE_TRACE().

    v2: Made the DECLARE_TRACE() have the ability to pass arguments
    and added a new DECLARE_TRACE_NOARGS() for tracepoints that
    do not need any arguments.

    Acked-by: Mathieu Desnoyers
    Acked-by: Masami Hiramatsu
    Acked-by: Frederic Weisbecker
    Cc: Neil Horman
    Cc: David S. Miller
    Signed-off-by: Steven Rostedt

    Steven Rostedt
     

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
     

10 Mar, 2010

1 commit


08 Mar, 2010

3 commits

  • Constify struct sysfs_ops.

    This is part of the ops structure constification
    effort started by Arjan van de Ven et al.

    Benefits of this constification:

    * prevents modification of data that is shared
    (referenced) by many other structure instances
    at runtime

    * detects/prevents accidental (but not intentional)
    modification attempts on archs that enforce
    read-only kernel data at runtime

    * potentially better optimized code as the compiler
    can assume that the const data cannot be changed

    * the compiler/linker move const data into .rodata
    and therefore exclude them from false sharing

    Signed-off-by: Emese Revfy
    Acked-by: David Teigland
    Acked-by: Matt Domsch
    Acked-by: Maciej Sosnowski
    Acked-by: Hans J. Koch
    Acked-by: Pekka Enberg
    Acked-by: Jens Axboe
    Acked-by: Stephen Hemminger
    Signed-off-by: Greg Kroah-Hartman

    Emese Revfy
     
  • No change in functionality.

    Signed-off-by: Radu Voicilas
    Signed-off-by: Greg Kroah-Hartman

    Radu Voicilas
     
  • No change in functionality.

    Signed-off-by: Radu Voicilas
    Signed-off-by: Greg Kroah-Hartman

    Radu Voicilas
     

27 Feb, 2010

1 commit

  • Add __percpu sparse annotations to hw_breakpoint.

    These annotations are to make sparse consider percpu variables to be
    in a different address space and warn if accessed without going
    through percpu accessors. This patch doesn't affect normal builds.

    In kernel/hw_breakpoint.c, per_cpu(nr_task_bp_pinned, cpu)'s will
    trigger spurious noderef related warnings from sparse. Changing it to
    &per_cpu(nr_task_bp_pinned[0], cpu) will work around the problem but
    deemed to ugly by the maintainer. Leave it alone until better
    solution can be found.

    Signed-off-by: Tejun Heo
    Cc: Stephen Rothwell
    Cc: K.Prasad
    LKML-Reference:
    Signed-off-by: Frederic Weisbecker

    Tejun Heo
     

12 Dec, 2009

1 commit

  • …/git/tip/linux-2.6-tip

    * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (57 commits)
    x86, perf events: Check if we have APIC enabled
    perf_event: Fix variable initialization in other codepaths
    perf kmem: Fix unused argument build warning
    perf symbols: perf_header__read_build_ids() offset'n'size should be u64
    perf symbols: dsos__read_build_ids() should read both user and kernel buildids
    perf tools: Align long options which have no short forms
    perf kmem: Show usage if no option is specified
    sched: Mark sched_clock() as notrace
    perf sched: Add max delay time snapshot
    perf tools: Correct size given to memset
    perf_event: Fix perf_swevent_hrtimer() variable initialization
    perf sched: Fix for getting task's execution time
    tracing/kprobes: Fix field creation's bad error handling
    perf_event: Cleanup for cpu_clock_perf_event_update()
    perf_event: Allocate children's perf_event_ctxp at the right time
    perf_event: Clean up __perf_event_init_context()
    hw-breakpoints: Modify breakpoints without unregistering them
    perf probe: Update perf-probe document
    perf probe: Support --del option
    trace-kprobe: Support delete probe syntax
    ...

    Linus Torvalds
     

08 Dec, 2009

1 commit


06 Dec, 2009

1 commit

  • struct perf_event::event callback was called when a breakpoint
    triggers. But this is a rather opaque callback, pretty
    tied-only to the breakpoint API and not really integrated into perf
    as it triggers even when we don't overflow.

    We prefer to use overflow_handler() as it fits into the perf events
    rules, being called only when we overflow.

    Reported-by: Peter Zijlstra
    Signed-off-by: Frederic Weisbecker
    Cc: Paul Mackerras
    Cc: Arnaldo Carvalho de Melo
    Cc: "K. Prasad"

    Frederic Weisbecker
     

27 Nov, 2009

1 commit

  • Kernel breakpoints are created using functions in which we pass
    breakpoint parameters as individual variables: address, length
    and type.

    Although it fits well for x86, this just does not scale across
    architectures that may support this api later as these may have
    more or different needs. Pass in a perf_event_attr structure
    instead because it is meant to evolve as much as possible into
    a generic hardware breakpoint parameter structure.

    Reported-by: K.Prasad
    Signed-off-by: Frederic Weisbecker
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Frederic Weisbecker
     

26 Nov, 2009

1 commit

  • This simplifies the error handling when we create a breakpoint.
    We don't need to check the NULL return value corner case anymore
    since we have improved perf_event_create_kernel_counter() to
    always return an error code in the failure case.

    Signed-off-by: Frederic Weisbecker
    Cc: Peter Zijlstra
    Cc: Arnaldo Carvalho de Melo
    Cc: Paul Mackerras
    Cc: Steven Rostedt
    Cc: Prasad
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Frederic Weisbecker
     

24 Nov, 2009

1 commit


10 Nov, 2009

1 commit


09 Nov, 2009

1 commit


18 Oct, 2009

1 commit


02 Oct, 2009

1 commit


19 Sep, 2009

1 commit

  • Now that the last users of markers have migrated to the event
    tracer we can kill off the (now orphan) support code.

    Signed-off-by: Christoph Hellwig
    Acked-by: Mathieu Desnoyers
    Cc: Steven Rostedt
    Cc: Frederic Weisbecker
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Christoph Hellwig
     

16 Sep, 2009

1 commit


15 Sep, 2009

1 commit


07 Sep, 2009

1 commit