lkml.org 
[lkml]   [2011]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] x86: Add an option to disable decoding of MCE
    Date
    This patch applies to v2.6.37.
    ---

    On our systems, we do not want to have any "decoders" called on machine
    check events. These decoders can easily spam our logs and cause space
    problems on machines that have a lot of correctable error events. We
    _do_ however want to get the messages delivered via /dev/mcelog for
    userland processing.

    Introduce an interface "dont_decode" that allows us to skip the
    decoders. We always call the decoders by default.

    Google-Bug-Id: 3289142
    Signed-off-by: Mike Waychison <mikew@google.com>
    ---
    arch/x86/kernel/cpu/mcheck/mce.c | 24 ++++++++++++++++++------
    1 files changed, 18 insertions(+), 6 deletions(-)

    diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
    index 7a35b72..3c30057 100644
    --- a/arch/x86/kernel/cpu/mcheck/mce.c
    +++ b/arch/x86/kernel/cpu/mcheck/mce.c
    @@ -82,6 +82,7 @@ static int mce_bootlog __read_mostly = -1;
    static int monarch_timeout __read_mostly = -1;
    static int mce_panic_timeout __read_mostly;
    static int mce_dont_log_ce __read_mostly;
    +static int mce_dont_decode __read_mostly;
    int mce_cmci_disabled __read_mostly;
    int mce_ignore_ce __read_mostly;
    int mce_ser __read_mostly;
    @@ -209,6 +210,17 @@ void mce_log(struct mce *mce)
    set_bit(0, &mce_need_notify);
    }

    +static void call_decoders(struct mce *m)
    +{
    + if (mce_dont_decode)
    + return;
    + /*
    + * Print out human-readable details about the MCE error,
    + * (if the CPU has an implementation for that)
    + */
    + atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, m);
    +}
    +
    static void print_mce(struct mce *m)
    {
    pr_emerg(HW_ERR "CPU %d: Machine Check Exception: %Lx Bank %d: %016Lx\n",
    @@ -234,11 +246,7 @@ static void print_mce(struct mce *m)
    pr_emerg(HW_ERR "PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x\n",
    m->cpuvendor, m->cpuid, m->time, m->socketid, m->apicid);

    - /*
    - * Print out human-readable details about the MCE error,
    - * (if the CPU has an implementation for that)
    - */
    - atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, m);
    + call_decoders(m);
    }

    #define PANIC_TIMEOUT 5 /* 5 seconds */
    @@ -588,7 +596,7 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
    */
    if (!(flags & MCP_DONTLOG) && !mce_dont_log_ce) {
    mce_log(&m);
    - atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, &m);
    + call_decoders(&m);
    add_taint(TAINT_MACHINE_CHECK);
    }

    @@ -1700,6 +1708,8 @@ static int __init mcheck_enable(char *str)
    mce_cmci_disabled = 1;
    else if (!strcmp(str, "dont_log_ce"))
    mce_dont_log_ce = 1;
    + else if (!strcmp(str, "dont_decode"))
    + mce_dont_decode = 1;
    else if (!strcmp(str, "ignore_ce"))
    mce_ignore_ce = 1;
    else if (!strcmp(str, "bootlog") || !strcmp(str, "nobootlog"))
    @@ -1926,6 +1936,7 @@ static SYSDEV_ATTR(trigger, 0644, show_trigger, set_trigger);
    static SYSDEV_INT_ATTR(tolerant, 0644, tolerant);
    static SYSDEV_INT_ATTR(monarch_timeout, 0644, monarch_timeout);
    static SYSDEV_INT_ATTR(dont_log_ce, 0644, mce_dont_log_ce);
    +static SYSDEV_INT_ATTR(dont_decode, 0644, mce_dont_decode);

    static struct sysdev_ext_attribute attr_check_interval = {
    _SYSDEV_ATTR(check_interval, 0644, sysdev_show_int,
    @@ -1949,6 +1960,7 @@ static struct sysdev_attribute *mce_attrs[] = {
    &attr_trigger,
    &attr_monarch_timeout.attr,
    &attr_dont_log_ce.attr,
    + &attr_dont_decode.attr,
    &attr_ignore_ce.attr,
    &attr_cmci_disabled.attr,
    NULL
    --
    1.7.3.1


    \
     
     \ /
      Last update: 2011-01-10 23:49    [W:0.027 / U:29.704 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site