[CRIU] [PATCH RFC] criu: add a debug version of rst-malloc

[Andrei Vagin]

On Fri, Mar 31, 2017 at 07:12:05PM +0300, Dmitry Safonov wrote:
> 2017-03-30 8:30 GMT+03:00 Andrei Vagin <avagin at openvz.org>:
> > From: Andrei Vagin <avagin at virtuozzo.com>
> >
> > rst_mem_alloc() can move all allocated objects and
> > the problem is that we don't know when it will do.
> >
> > With this patch, if the criu is built with DEBUG=1,
> > rst_mem_alloc() will move objects each time.
> >
> > Signed-off-by: Andrei Vagin <avagin at virtuozzo.com>
> > ---
> >  .travis.yml                 |  1 +
> >  criu/rst-malloc.c           | 19 +++++++++++++++++++
> >  scripts/travis/travis-tests |  2 +-
> >  3 files changed, 21 insertions(+), 1 deletion(-)
> >
> > diff --git a/.travis.yml b/.travis.yml
> > index a5dfb9f..d62e086 100644
> > --- a/.travis.yml
> > +++ b/.travis.yml
> > @@ -7,6 +7,7 @@ services:
> >  env:
> >    - TR_ARCH=local       GCOV=1
> >    - TR_ARCH=local       CLANG=1
> > +  - TR_ARCH=local       CRIU_DEBUG=1
> >    - TR_ARCH=alpine
> >    - TR_ARCH=x86_64
> >    - TR_ARCH=armv7hf
> > diff --git a/criu/rst-malloc.c b/criu/rst-malloc.c
> > index 4f7357c..057fa31 100644
> > --- a/criu/rst-malloc.c
> > +++ b/criu/rst-malloc.c
> > @@ -23,6 +23,11 @@ static inline unsigned long rst_mem_grow(unsigned long need_size)
> >  {
> >         int rst_mem_batch = 2 * page_size();
> >
> > +#ifdef CR_DEBUG
> > +       if (need_size == 0)
> > +               return 0;
> > +#endif
> > +
> >         need_size = round_up(need_size, page_size());
> >         if (likely(need_size < rst_mem_batch))
> >                 need_size = rst_mem_batch;
> > @@ -88,8 +93,18 @@ static int grow_remap(struct rst_mem_type_s *t, int flag, unsigned long size)
> >                  * a completely new one and force callers use objects'
> >                  * cpos-s.
> >                  */
> > +#ifdef CR_DEBUG
> 
> Could we name it somehow more descriptive?
> So we wouldn't introduce large CR_DEBUG for everything,
> and say DEBUG_RST_ALLOC?
> And just add it in makefile here:
> 
> ifeq ($(DEBUG),1)
>         DEFINES        += -DCR_DEBUG -DDEBUG_RST_ALLOC

I think it is a good idea. Will send a new version. Thank you
> 
> Or maybe you could come with a better name.
> 
> Maybe even some day we could have it as a build option
> in .config along with some other.
> 
> > +               /* Move vma each time to another palce */
> > +               void *ptr = mmap(NULL, t->size + size, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
> > +               if (ptr == MAP_FAILED)
> > +                       return -1;
> > +               aux = mremap(t->buf, t->size,
> > +                               t->size + size, MREMAP_MAYMOVE | MREMAP_FIXED, ptr);
> > +               munmap(t->buf, t->size);
> > +#else
> >                 aux = mremap(t->buf, t->size,
> >                                 t->size + size, MREMAP_MAYMOVE);
> > +#endif
> >         }
> >         if (aux == MAP_FAILED)
> >                 return -1;
> > @@ -175,6 +190,10 @@ void *rst_mem_alloc(unsigned long size, int type)
> >                 pr_perror("Can't grow rst mem");
> >                 return NULL;
> >         }
> > +#ifdef CR_DEBUG
> > +       else if (type == RM_PRIVATE && t->grow(t, 0)) /* Move a vma to another place */
> > +               return NULL;
> > +#endif
> >
> >         ret = t->free_mem;
> >         t->free_mem += size;
> > diff --git a/scripts/travis/travis-tests b/scripts/travis/travis-tests
> > index 37117a3..3897542 100755
> > --- a/scripts/travis/travis-tests
> > +++ b/scripts/travis/travis-tests
> > @@ -41,7 +41,7 @@ ulimit -c unlimited
> >  echo "|`pwd`/test/abrt.sh %P %p %s %e" > /proc/sys/kernel/core_pattern
> >
> >  export GCOV
> > -time make CC="$CC" -j4
> > +time make CC="$CC" DEBUG="$CRIU_DEBUG" -j4
> >  time make CC="$CC" -j4 -C test/zdtm
> >
> >  [ -f "$CCACHE_LOGFILE" ] && cat $CCACHE_LOGFILE
> > --
> > 2.7.4
> >
> > _______________________________________________
> > CRIU mailing list
> > CRIU at openvz.org
> > https://lists.openvz.org/mailman/listinfo/criu
> 
> 
> 
> -- 
>              Dmitry