01 Nov, 2011

1 commit


22 Jun, 2011

2 commits

  • This patch adds 2 tracepoints to get a status of a socket receive queue
    and related parameter.

    One tracepoint is added to sock_queue_rcv_skb. It records rcvbuf size
    and its usage. The other tracepoint is added to __sk_mem_schedule and
    it records limitations of memory for sockets and current usage.

    By using these tracepoints we're able to know detailed reason why kernel
    drop the packet.

    Signed-off-by: Satoru Moriya
    Acked-by: Neil Horman
    Signed-off-by: David S. Miller

    Satoru Moriya
     
  • This patch adds a tracepoint to __udp_queue_rcv_skb to get the
    return value of ip_queue_rcv_skb. It indicates why kernel drops
    a packet at this point.

    ip_queue_rcv_skb returns following values in the packet drop case:

    rcvbuf is full : -ENOMEM
    sk_filter returns error : -EINVAL, -EACCESS, -ENOMEM, etc.
    __sk_mem_schedule returns error: -ENOBUF

    Signed-off-by: Satoru Moriya
    Acked-by: Neil Horman
    Signed-off-by: David S. Miller

    Satoru Moriya
     

07 Sep, 2010

1 commit

  • This patch adds tracepoint to dev_queue_xmit, dev_hard_start_xmit,
    netif_rx and netif_receive_skb. These tracepoints help you to monitor
    network driver's input/output.

    -0 [001] 112447.902030: netif_rx: dev=eth1 skbaddr=f3ef0900 len=84
    -0 [001] 112447.902039: netif_receive_skb: dev=eth1 skbaddr=f3ef0900 len=84
    sshd-6828 [000] 112447.903257: net_dev_queue: dev=eth4 skbaddr=f3fca538 len=226
    sshd-6828 [000] 112447.903260: net_dev_xmit: dev=eth4 skbaddr=f3fca538 len=226 rc=0

    Signed-off-by: Koki Sanagi
    Acked-by: David S. Miller
    Acked-by: Neil Horman
    Cc: Mathieu Desnoyers
    Cc: Kaneshige Kenji
    Cc: Izumo Taku
    Cc: Kosaki Motohiro
    Cc: Lai Jiangshan
    Cc: Scott Mcmillan
    Cc: Steven Rostedt
    Cc: Eric Dumazet
    LKML-Reference:
    Signed-off-by: Frederic Weisbecker

    Koki Sanagi
     

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
     

15 Jun, 2009

1 commit


22 May, 2009

1 commit

  • Patch to add the ability to detect drops in hardware interfaces via dropwatch.
    Adds a tracepoint to net_rx_action to signal everytime a napi instance is
    polled. The dropmon code then periodically checks to see if the rx_frames
    counter has changed, and if so, adds a drop notification to the netlink
    protocol, using the reserved all-0's vector to indicate the drop location was in
    hardware, rather than somewhere in the code.

    Signed-off-by: Neil Horman

    include/linux/net_dropmon.h | 8 ++
    include/trace/napi.h | 11 +++
    net/core/dev.c | 5 +
    net/core/drop_monitor.c | 124 ++++++++++++++++++++++++++++++++++++++++++--
    net/core/net-traces.c | 4 +
    net/core/netpoll.c | 2
    6 files changed, 149 insertions(+), 5 deletions(-)
    Signed-off-by: David S. Miller

    Neil Horman
     

15 Apr, 2009

2 commits

  • Impact: clean up

    Create a sub directory in include/trace called events to keep the
    trace point headers in their own separate directory. Only headers that
    declare trace points should be defined in this directory.

    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: Neil Horman
    Cc: Zhao Lei
    Cc: Eduard - Gabriel Munteanu
    Cc: Pekka Enberg
    Signed-off-by: Steven Rostedt

    Steven Rostedt
     
  • This patch lowers the number of places a developer must modify to add
    new tracepoints. The current method to add a new tracepoint
    into an existing system is to write the trace point macro in the
    trace header with one of the macros TRACE_EVENT, TRACE_FORMAT or
    DECLARE_TRACE, then they must add the same named item into the C file
    with the macro DEFINE_TRACE(name) and then add the trace point.

    This change cuts out the needing to add the DEFINE_TRACE(name).
    Every file that uses the tracepoint must still include the trace/.h
    file, but the one C file must also add a define before the including
    of that file.

    #define CREATE_TRACE_POINTS
    #include

    This will cause the trace/mytrace.h file to also produce the C code
    necessary to implement the trace point.

    Note, if more than one trace/.h is used to create the C code
    it is best to list them all together.

    #define CREATE_TRACE_POINTS
    #include
    #include
    #include

    Thanks to Mathieu Desnoyers and Christoph Hellwig for coming up with
    the cleaner solution of the define above the includes over my first
    design to have the C code include a "special" header.

    This patch converts sched, irq and lockdep and skb to use this new
    method.

    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: Neil Horman
    Cc: Zhao Lei
    Cc: Eduard - Gabriel Munteanu
    Cc: Pekka Enberg
    Signed-off-by: Steven Rostedt

    Steven Rostedt
     

14 Mar, 2009

1 commit