Am 25.02.2013 um 13:15 schrieb Orit Wasserman <owass...@redhat.com>:
> Hi Peter,
> Now I get the previous patch, it should have been a patch series :).
> The reason we allocate from outside of the page cache is because of
> cache_resize
> that also uses cache_insert but doesn't duplicate the buffer.
> There is no memory leak because if the page is cached we don't call
> cache_insert
> but do memcpy instead.
Ah ok, haven't noticed the resize case. But there is still a men leak on a
simple collision (first patch) - nothing
to do with resize.
We should discuss if the page cache frees data it should also allocate the
data. Maybe we need to different functions.
Peter
>
> Regards,
> Orit
> On 02/25/2013 01:52 PM, Peter Lieven wrote:
>> The page cache frees all data on finish, on resize and
>> if there is collision on insert. So it should be the caches
>> responsibility to dup the data that is stored in the cache.
>>
>> Signed-off-by: Peter Lieven <p...@kamp.de>
>> ---
>> arch_init.c | 3 +--
>> include/migration/page_cache.h | 3 ++-
>> page_cache.c | 2 +-
>> 3 files changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch_init.c b/arch_init.c
>> index 8da868b..97bcc29 100644
>> --- a/arch_init.c
>> +++ b/arch_init.c
>> @@ -293,8 +293,7 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t
>> *current_data,
>>
>> if (!cache_is_cached(XBZRLE.cache, current_addr)) {
>> if (!last_stage) {
>> - cache_insert(XBZRLE.cache, current_addr,
>> - g_memdup(current_data, TARGET_PAGE_SIZE));
>> + cache_insert(XBZRLE.cache, current_addr, current_data);
>> }
>> acct_info.xbzrle_cache_miss++;
>> return -1;
>> diff --git a/include/migration/page_cache.h b/include/migration/page_cache.h
>> index 3839ac7..87894fe 100644
>> --- a/include/migration/page_cache.h
>> +++ b/include/migration/page_cache.h
>> @@ -57,7 +57,8 @@ bool cache_is_cached(const PageCache *cache, uint64_t
>> addr);
>> uint8_t *get_cached_data(const PageCache *cache, uint64_t addr);
>>
>> /**
>> - * cache_insert: insert the page into the cache. the previous value will be
>> overwritten
>> + * cache_insert: insert the page into the cache. the page cache
>> + * will dup the data on insert. the previous value will be overwritten
>> *
>> * @cache pointer to the PageCache struct
>> * @addr: page address
>> diff --git a/page_cache.c b/page_cache.c
>> index a6c3a15..e670d91 100644
>> --- a/page_cache.c
>> +++ b/page_cache.c
>> @@ -158,7 +158,7 @@ void cache_insert(PageCache *cache, uint64_t addr,
>> uint8_t *pdata)
>> g_free(it->it_data);
>> }
>>
>> - it->it_data = pdata;
>> + it->it_data = g_memdup(pdata, cache->page_size);
>> it->it_age = ++cache->max_item_age;
>> it->it_addr = addr;
>> }
>
