diff options
| -rw-r--r-- | arch_init.c | 52 |
1 files changed, 49 insertions, 3 deletions
diff --git a/arch_init.c b/arch_init.c index fe1727922c..60c975db2b 100644 --- a/arch_init.c +++ b/arch_init.c @@ -164,8 +164,9 @@ static struct { uint8_t *encoded_buf; /* buffer for storing page content */ uint8_t *current_buf; - /* Cache for XBZRLE */ + /* Cache for XBZRLE, Protected by lock. */ PageCache *cache; + QemuMutex lock; } XBZRLE = { .encoded_buf = NULL, .current_buf = NULL, @@ -174,16 +175,52 @@ static struct { /* buffer used for XBZRLE decoding */ static uint8_t *xbzrle_decoded_buf; +static void XBZRLE_cache_lock(void) +{ + if (migrate_use_xbzrle()) + qemu_mutex_lock(&XBZRLE.lock); +} + +static void XBZRLE_cache_unlock(void) +{ + if (migrate_use_xbzrle()) + qemu_mutex_unlock(&XBZRLE.lock); +} + int64_t xbzrle_cache_resize(int64_t new_size) { + PageCache *new_cache, *cache_to_free; + if (new_size < TARGET_PAGE_SIZE) { return -1; } + /* no need to lock, the current thread holds qemu big lock */ if (XBZRLE.cache != NULL) { - return cache_resize(XBZRLE.cache, new_size / TARGET_PAGE_SIZE) * - TARGET_PAGE_SIZE; + /* check XBZRLE.cache again later */ + if (pow2floor(new_size) == migrate_xbzrle_cache_size()) { + return pow2floor(new_size); + } + new_cache = cache_init(new_size / TARGET_PAGE_SIZE, + TARGET_PAGE_SIZE); + if (!new_cache) { + DPRINTF("Error creating cache\n"); + return -1; + } + + XBZRLE_cache_lock(); + /* the XBZRLE.cache may have be destroyed, check it again */ + if (XBZRLE.cache != NULL) { + cache_to_free = XBZRLE.cache; + XBZRLE.cache = new_cache; + } else { + cache_to_free = new_cache; + } + XBZRLE_cache_unlock(); + + cache_fini(cache_to_free); } + return pow2floor(new_size); } @@ -539,6 +576,8 @@ static int ram_save_block(QEMUFile *f, bool last_stage) ret = ram_control_save_page(f, block->offset, offset, TARGET_PAGE_SIZE, &bytes_sent); + XBZRLE_cache_lock(); + current_addr = block->offset + offset; if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { if (ret != RAM_SAVE_CONTROL_DELAYED) { @@ -587,6 +626,7 @@ static int ram_save_block(QEMUFile *f, bool last_stage) acct_info.norm_pages++; } + XBZRLE_cache_unlock(); /* if page is unmodified, continue to the next */ if (bytes_sent > 0) { last_sent_block = block; @@ -654,6 +694,7 @@ static void migration_end(void) migration_bitmap = NULL; } + XBZRLE_cache_lock(); if (XBZRLE.cache) { cache_fini(XBZRLE.cache); g_free(XBZRLE.cache); @@ -663,6 +704,7 @@ static void migration_end(void) XBZRLE.encoded_buf = NULL; XBZRLE.current_buf = NULL; } + XBZRLE_cache_unlock(); } static void ram_migration_cancel(void *opaque) @@ -693,13 +735,17 @@ static int ram_save_setup(QEMUFile *f, void *opaque) dirty_rate_high_cnt = 0; if (migrate_use_xbzrle()) { + qemu_mutex_lock_iothread(); XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() / TARGET_PAGE_SIZE, TARGET_PAGE_SIZE); if (!XBZRLE.cache) { + qemu_mutex_unlock_iothread(); DPRINTF("Error creating cache\n"); return -1; } + qemu_mutex_init(&XBZRLE.lock); + qemu_mutex_unlock_iothread(); /* We prefer not to abort if there is no memory */ XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE); |