* Wei Yang (richardw.y...@linux.intel.com) wrote:
> Even we need to do discard for each RAMBlock, we still can leverage the
> same memory space to store the information.
>
> By doing so, we avoid memory allocation and deallocation to the system
> and also avoid potential failure of memory allocation which breaks the
> migration.
>
> Signed-off-by: Wei Yang <richardw.y...@linux.intel.com>
> ---
> migration/postcopy-ram.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
> index 9faacacc9e..2e6b076bb7 100644
> --- a/migration/postcopy-ram.c
> +++ b/migration/postcopy-ram.c
> @@ -1377,8 +1377,7 @@ void
> postcopy_fault_thread_notify(MigrationIncomingState *mis)
> * asking to discard individual ranges.
> *
> * @ms: The current migration state.
> - * @offset: the bitmap offset of the named RAMBlock in the migration
> - * bitmap.
> + * @offset: the bitmap offset of the named RAMBlock in the migration bitmap.
> * @name: RAMBlock that discards will operate on.
> *
> * returns: a new PDS.
> @@ -1386,13 +1385,14 @@ void
> postcopy_fault_thread_notify(MigrationIncomingState *mis)
> PostcopyDiscardState *postcopy_discard_send_init(MigrationState *ms,
> const char *name)
> {
> - PostcopyDiscardState *res = g_malloc0(sizeof(PostcopyDiscardState));
> + static PostcopyDiscardState res = {0};
Do you think it would be better to make this a static at the top of
migration/postcopy-ram.c and then we could remove the pds parameters
from postcopy_discard_send_range and friends?
If there's only one pds then we don't need to pass the pointer around.
Dave
> - if (res) {
> - res->ramblock_name = name;
> - }
> + res.ramblock_name = name;
> + res.cur_entry = 0;
> + res.nsentwords = 0;
> + res.nsentcmds = 0;
>
> - return res;
> + return &res;
> }
>
> /**
> @@ -1449,8 +1449,6 @@ void postcopy_discard_send_finish(MigrationState *ms,
> PostcopyDiscardState *pds)
>
> trace_postcopy_discard_send_finish(pds->ramblock_name, pds->nsentwords,
> pds->nsentcmds);
> -
> - g_free(pds);
> }
>
> /*
> --
> 2.17.1
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
