perf kvm: Fix memory leak

[PATCH 0/2] perf kvm: Fix memory leak

Posted by Leo Yan 2 years, 10 months ago

This patch seris is to address memory leak issues in perf kvm.

The first patch introduces refcnt in structure kvm_info, so we can avoid
memory leak for it.

The second patch explicitly delete histograms entries before program
exiting rather than relying on kernel releasing memory space.


Leo Yan (2):
  perf kvm: Support refcnt in structure kvm_info
  perf kvm: Delete histograms entries before exiting

 tools/perf/builtin-kvm.c   |  6 ++++--
 tools/perf/util/hist.c     |  5 +++++
 tools/perf/util/kvm-stat.h | 37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+), 2 deletions(-)

-- 
2.39.2

Re: [PATCH 0/2] perf kvm: Fix memory leak

Posted by Ian Rogers 2 years, 10 months ago

On Sun, Mar 19, 2023 at 11:16 PM Leo Yan <leo.yan@linaro.org> wrote:
>
> This patch seris is to address memory leak issues in perf kvm.
>
> The first patch introduces refcnt in structure kvm_info, so we can avoid
> memory leak for it.
>
> The second patch explicitly delete histograms entries before program
> exiting rather than relying on kernel releasing memory space.
>

Series:
Acked-by: Ian Rogers <irogers@google.com>

Thanks,
Ian

> Leo Yan (2):
>   perf kvm: Support refcnt in structure kvm_info
>   perf kvm: Delete histograms entries before exiting
>
>  tools/perf/builtin-kvm.c   |  6 ++++--
>  tools/perf/util/hist.c     |  5 +++++
>  tools/perf/util/kvm-stat.h | 37 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 46 insertions(+), 2 deletions(-)
>
> --
> 2.39.2
>

Re: [PATCH 0/2] perf kvm: Fix memory leak

Posted by Arnaldo Carvalho de Melo 2 years, 10 months ago

Em Mon, Mar 20, 2023 at 10:43:11AM -0700, Ian Rogers escreveu:
> On Sun, Mar 19, 2023 at 11:16 PM Leo Yan <leo.yan@linaro.org> wrote:
> >
> > This patch seris is to address memory leak issues in perf kvm.
> >
> > The first patch introduces refcnt in structure kvm_info, so we can avoid
> > memory leak for it.
> >
> > The second patch explicitly delete histograms entries before program
> > exiting rather than relying on kernel releasing memory space.
> >
> 
> Series:
> Acked-by: Ian Rogers <irogers@google.com>

I applied this, but the second patch may end up delaying tool exit by
traversing data structures holding lots of objects to needless free
them.

There are places in perf where we do it conditionally for that reason.

At some point I want to try signalling we're exiting using some global
variable and then making all memory free operations become nops.

- Arnaldo


 
> Thanks,
> Ian
> 
> > Leo Yan (2):
> >   perf kvm: Support refcnt in structure kvm_info
> >   perf kvm: Delete histograms entries before exiting
> >
> >  tools/perf/builtin-kvm.c   |  6 ++++--
> >  tools/perf/util/hist.c     |  5 +++++
> >  tools/perf/util/kvm-stat.h | 37 +++++++++++++++++++++++++++++++++++++
> >  3 files changed, 46 insertions(+), 2 deletions(-)
> >
> > --
> > 2.39.2
> >

-- 

- Arnaldo