lkml.org 
[lkml]   [2020]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v2 7/7][next] scripts/gdb: support printk finalized records
    Date
    With commit ("printk: ringbuffer: add finalization/extension support")
    a new state bit for finalized records was added. This not only changed
    the bit representation of committed records, but also reduced the size
    for record IDs.

    Update the gdb scripts to correctly interpret the state variable.

    Signed-off-by: John Ogness <john.ogness@linutronix.de>
    ---
    Documentation/admin-guide/kdump/gdbmacros.txt | 10 +++++++---
    scripts/gdb/linux/dmesg.py | 10 ++++++----
    2 files changed, 13 insertions(+), 7 deletions(-)

    diff --git a/Documentation/admin-guide/kdump/gdbmacros.txt b/Documentation/admin-guide/kdump/gdbmacros.txt
    index 6025534c6c14..1ccc811c82ad 100644
    --- a/Documentation/admin-guide/kdump/gdbmacros.txt
    +++ b/Documentation/admin-guide/kdump/gdbmacros.txt
    @@ -295,8 +295,11 @@ document dump_record
    end

    define dmesg
    - set var $desc_committed = 1UL << ((sizeof(long) * 8) - 1)
    - set var $flags_mask = 3UL << ((sizeof(long) * 8) - 2)
    + # definitions from kernel/printk/printk_ringbuffer.h
    + set var $desc_commit = 1UL << ((sizeof(long) * 8) - 1)
    + set var $desc_final = 1UL << ((sizeof(long) * 8) - 2)
    + set var $desc_reuse = 1UL << ((sizeof(long) * 8) - 3)
    + set var $flags_mask = $desc_commit | $desc_final | $desc_reuse
    set var $id_mask = ~$flags_mask

    set var $desc_count = 1U << prb->desc_ring.count_bits
    @@ -309,7 +312,8 @@ define dmesg
    set var $desc = &prb->desc_ring.descs[$id % $desc_count]

    # skip non-committed record
    - if (($desc->state_var.counter & $flags_mask) == $desc_committed)
    + # (note that commit+!final records will be displayed)
    + if (($desc->state_var.counter & $desc_commit) == $desc_commit)
    dump_record $desc $prev_flags
    set var $prev_flags = $desc->info.flags
    end
    diff --git a/scripts/gdb/linux/dmesg.py b/scripts/gdb/linux/dmesg.py
    index 6c6022012ea8..367523c5c270 100644
    --- a/scripts/gdb/linux/dmesg.py
    +++ b/scripts/gdb/linux/dmesg.py
    @@ -79,9 +79,10 @@ class LxDmesg(gdb.Command):

    # definitions from kernel/printk/printk_ringbuffer.h
    desc_sv_bits = utils.get_long_type().sizeof * 8
    - desc_committed_mask = 1 << (desc_sv_bits - 1)
    - desc_reuse_mask = 1 << (desc_sv_bits - 2)
    - desc_flags_mask = desc_committed_mask | desc_reuse_mask
    + desc_commit_mask = 1 << (desc_sv_bits - 1)
    + desc_final_mask = 1 << (desc_sv_bits - 2)
    + desc_reuse_mask = 1 << (desc_sv_bits - 3)
    + desc_flags_mask = desc_commit_mask | desc_final_mask | desc_reuse_mask
    desc_id_mask = ~desc_flags_mask

    # read in tail and head descriptor ids
    @@ -96,8 +97,9 @@ class LxDmesg(gdb.Command):
    desc_off = desc_sz * ind

    # skip non-committed record
    + # (note that commit+!final records will be displayed)
    state = utils.read_u64(descs, desc_off + sv_off + counter_off) & desc_flags_mask
    - if state != desc_committed_mask:
    + if state & desc_commit_mask != desc_commit_mask:
    if did == head_id:
    break
    did = (did + 1) & desc_id_mask
    --
    2.20.1
    \
     
     \ /
      Last update: 2020-08-24 12:37    [W:7.911 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site