svn commit: r317061 - in head: libexec/rpc.rstatd sys/amd64/amd64 sys/amd64/include sys/arm/arm sys/arm/include sys/arm64/include sys/cddl/contrib/opensolaris/uts/common/fs/zfs sys/compat/linprocfs...

[Larry Rosenman]

On 4/18/17, 2:58 PM, "Alan Somers" <owner-svn-src-all at freebsd.org on behalf of asomers at freebsd.org> wrote:

    On Mon, Apr 17, 2017 at 11:34 AM, Gleb Smirnoff <glebius at freebsd.org> wrote:
    > Author: glebius
    > Date: Mon Apr 17 17:34:47 2017
    > New Revision: 317061
    > URL: https://svnweb.freebsd.org/changeset/base/317061
    >
    > Log:
    >   - Remove 'struct vmmeter' from 'struct pcpu', leaving only global vmmeter
    >     in place.  To do per-cpu stats, convert all fields that previously were
    >     maintained in the vmmeters that sit in pcpus to counter(9).
    >   - Since some vmmeter stats may be touched at very early stages of boot,
    >     before we have set up UMA and we can do counter_u64_alloc(), provide an
    >     early counter mechanism:
    >     o Leave one spare uint64_t in struct pcpu, named pc_early_dummy_counter.
    >     o Point counter(9) fields of vmmeter to pcpu[0].pc_early_dummy_counter,
    >       so that at early stages of boot, before counters are allocated we already
    >       point to a counter that can be safely written to.
    >     o For sparc64 that required a whole dummy pcpu[MAXCPU] array.
    >
    >   Further related changes:
    >   - Don't include vmmeter.h into pcpu.h.
    >   - vm.stats.vm.v_swappgsout and vm.stats.vm.v_swappgsin changed to 64-bit,
    >     to match kernel representation.
    >   - struct vmmeter hidden under _KERNEL, and only vmstat(1) is an exclusion.
    >
    >   This is based on benno@'s 4-year old patch:
    >   https://lists.freebsd.org/pipermail/freebsd-arch/2013-July/014471.html
    >
    >   Reviewed by:  kib, gallatin, marius, lidl
    >   Differential Revision:        https://reviews.freebsd.org/D10156
    >
This change broke backwards compatibility with old top binaries.  When
    I use a kernel at version 317094 but a top from 14-April, I get the
    error "top: sysctl(vm.stats.vm.v_swappgsin...) failed: Cannot allocate
    memory".  I get the same error when running top from an 11.0-RELEASE
    jail.  Can you please add backward compatibility shims?
    
    -Alan
It also broke emulators/virtualbox-ose-kmod