lkml.org 
[lkml]   [2020]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 09/11] EDAC/ghes: Implement DIMM mapping table for SMBIOS handles
    On Fri, Mar 06, 2020 at 04:13:16PM +0100, Robert Richter wrote:
    > GHES uses SMBIOS handles to identify the DIMM that was causing a hw
    > error. Currently this is stored in smbios_handle of struct dimm_info.
    > This implementation has several drawbacks. The information is private
    > to the ghes driver, but struct dimm_info is for general use. The DIMMs
    > are tied to a *mci struct, which makes a lockup inefficient. It is

    "lookup"

    > hard to dynamically allocate DIMMs and also to meet locking
    > constraints when adding or removing them. This becomes even more
    > challenging when having multiple MC instances that group a set of
    > DIMMs, so the change is needed also to later support multiple MC
    > instances.

    Err, I don't understand: normally a bunch of DIMMs belong to a memory
    controller and that gives you the hierarchy automatically. Why is that a
    problem?

    And normally you allocate the DIMM representations on MC init and
    deallocate them when removing the MC.

    So what is the problem here?

    ...

    ...
    > @@ -72,6 +79,52 @@ struct memdev_dmi_entry {
    > u16 conf_mem_clk_speed;
    > } __attribute__((__packed__));
    >
    > +/* ghes_reg_mutex must be held. */

    lockdep_assert_held()

    ...

    --
    Regards/Gruss,
    Boris.

    https://people.kernel.org/tglx/notes-about-netiquette

    \
     
     \ /
      Last update: 2020-03-16 10:41    [W:2.670 / U:0.284 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site