On Thu, May 23, 2013 at 11:38:07AM +0800, Fam Zheng wrote: > Introduce a cache quota: BDRVCURLState.cache_quota. > When adding new CURLDataCache to BDRVCURLState, if number of existing > CURLDataCache is larger than CURL_CACHE_QUOTA, try to release some first > to limit the in memory cache size. > > A least used entry is selected for releasing. > > Signed-off-by: Fam Zheng <f...@redhat.com> > --- > block/curl.c | 27 +++++++++++++++++++++++++++ > 1 file changed, 27 insertions(+) > > diff --git a/block/curl.c b/block/curl.c > index 3ea2552..5adbc84 100644 > --- a/block/curl.c > +++ b/block/curl.c > @@ -40,6 +40,7 @@ > > #define SECTOR_SIZE 512 > #define READ_AHEAD_SIZE (256 * 1024) > +#define CURL_CACHE_QUOTA 10 > > struct BDRVCURLState; > > @@ -90,6 +91,8 @@ typedef struct BDRVCURLState { > QEMUTimer *timer; > /* List of data cache ordered by access, freed from tail */ > QLIST_HEAD(, CURLDataCache) cache; > + /* Threshold to release unused cache when cache list is longer than it */ > + int cache_quota; > /* Whether http server accept range in header */ > bool accept_range; > } BDRVCURLState; > @@ -526,6 +529,8 @@ static int curl_open(BlockDriverState *bs, QDict > *options, int flags) > curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running); > > qemu_opts_del(opts); > + s->cache_quota = CURL_CACHE_QUOTA; > + > return 0; > > out: > @@ -595,6 +600,27 @@ static void curl_readv_bh_cb(void *p) > cache->data_len = aio_bytes + s->readahead_size; > cache->write_pos = 0; > cache->data = g_malloc(cache->data_len); > + /* Try to release some cache */ > + while (0 && s->cache_quota <= 0) {
while (0) :(