diff options
| -rw-r--r-- | xen-mapcache.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/xen-mapcache.c b/xen-mapcache.c index 5b247ee092..7bcb86e4f8 100644 --- a/xen-mapcache.c +++ b/xen-mapcache.c @@ -40,6 +40,13 @@ #endif #define MCACHE_BUCKET_SIZE (1UL << MCACHE_BUCKET_SHIFT) +/* This is the size of the virtual address space reserve to QEMU that will not + * be use by MapCache. + * From empirical tests I observed that qemu use 75MB more than the + * max_mcache_size. + */ +#define NON_MCACHE_MEMORY_SIZE (80 * 1024 * 1024) + #define mapcache_lock() ((void)0) #define mapcache_unlock() ((void)0) @@ -92,15 +99,27 @@ void xen_map_cache_init(void) QTAILQ_INIT(&mapcache->locked_entries); mapcache->last_address_index = -1; - getrlimit(RLIMIT_AS, &rlimit_as); - if (rlimit_as.rlim_max < MCACHE_MAX_SIZE) { - rlimit_as.rlim_cur = rlimit_as.rlim_max; + if (geteuid() == 0) { + rlimit_as.rlim_cur = RLIM_INFINITY; + rlimit_as.rlim_max = RLIM_INFINITY; + mapcache->max_mcache_size = MCACHE_MAX_SIZE; } else { - rlimit_as.rlim_cur = MCACHE_MAX_SIZE; + getrlimit(RLIMIT_AS, &rlimit_as); + rlimit_as.rlim_cur = rlimit_as.rlim_max; + + if (rlimit_as.rlim_max != RLIM_INFINITY) { + fprintf(stderr, "Warning: QEMU's maximum size of virtual" + " memory is not infinity.\n"); + } + if (rlimit_as.rlim_max < MCACHE_MAX_SIZE + NON_MCACHE_MEMORY_SIZE) { + mapcache->max_mcache_size = rlimit_as.rlim_max - + NON_MCACHE_MEMORY_SIZE; + } else { + mapcache->max_mcache_size = MCACHE_MAX_SIZE; + } } setrlimit(RLIMIT_AS, &rlimit_as); - mapcache->max_mcache_size = rlimit_as.rlim_cur; mapcache->nr_buckets = (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) + |