From 90e56fb46d0a7add88ed463efa4e723a6238f692 Mon Sep 17 00:00:00 2001 From: Liang Li Date: Thu, 5 May 2016 15:32:56 +0800 Subject: [PATCH] migration: protect the quit flag by lock quit_comp_thread and quit_decomp_thread are accessed by several thread, it's better to protect them with locks. We use a per thread flag to replace the global one, and the new flag is protected by a lock. Signed-off-by: Liang Li Message-Id: <1462433579-13691-7-git-send-email-liang.z.li@intel.com> Signed-off-by: Amit Shah --- migration/ram.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 9e4f5e5efc..a5ed21b92a 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -255,6 +255,7 @@ static struct BitmapRcu { struct CompressParam { bool start; bool done; + bool quit; QEMUFile *file; QemuMutex mutex; QemuCond cond; @@ -266,6 +267,7 @@ typedef struct CompressParam CompressParam; struct DecompressParam { bool start; bool done; + bool quit; QemuMutex mutex; QemuCond cond; void *des; @@ -286,8 +288,6 @@ static QemuCond *comp_done_cond; static const QEMUFileOps empty_ops = { }; static bool compression_switch; -static bool quit_comp_thread; -static bool quit_decomp_thread; static DecompressParam *decomp_param; static QemuThread *decompress_threads; static QemuMutex decomp_done_lock; @@ -299,18 +299,18 @@ static void *do_data_compress(void *opaque) { CompressParam *param = opaque; - while (!quit_comp_thread) { + while (!param->quit) { qemu_mutex_lock(¶m->mutex); - /* Re-check the quit_comp_thread in case of + /* Re-check the quit flag in case of * terminate_compression_threads is called just before * qemu_mutex_lock(¶m->mutex) and after - * while(!quit_comp_thread), re-check it here can make + * while(!param->quit), re-check it here can make * sure the compression thread terminate as expected. */ - while (!param->start && !quit_comp_thread) { + while (!param->start && !param->quit) { qemu_cond_wait(¶m->cond, ¶m->mutex); } - if (!quit_comp_thread) { + if (!param->quit) { do_compress_ram_page(param); } param->start = false; @@ -330,9 +330,9 @@ static inline void terminate_compression_threads(void) int idx, thread_count; thread_count = migrate_compress_threads(); - quit_comp_thread = true; for (idx = 0; idx < thread_count; idx++) { qemu_mutex_lock(&comp_param[idx].mutex); + comp_param[idx].quit = true; qemu_cond_signal(&comp_param[idx].cond); qemu_mutex_unlock(&comp_param[idx].mutex); } @@ -372,7 +372,6 @@ void migrate_compress_threads_create(void) if (!migrate_use_compression()) { return; } - quit_comp_thread = false; compression_switch = true; thread_count = migrate_compress_threads(); compress_threads = g_new0(QemuThread, thread_count); @@ -387,6 +386,7 @@ void migrate_compress_threads_create(void) */ comp_param[i].file = qemu_fopen_ops(NULL, &empty_ops); comp_param[i].done = true; + comp_param[i].quit = false; qemu_mutex_init(&comp_param[i].mutex); qemu_cond_init(&comp_param[i].cond); qemu_thread_create(compress_threads + i, "compress", @@ -863,12 +863,12 @@ static void flush_compressed_data(QEMUFile *f) for (idx = 0; idx < thread_count; idx++) { if (!comp_param[idx].done) { qemu_mutex_lock(comp_done_lock); - while (!comp_param[idx].done && !quit_comp_thread) { + while (!comp_param[idx].done && !comp_param[idx].quit) { qemu_cond_wait(comp_done_cond, comp_done_lock); } qemu_mutex_unlock(comp_done_lock); } - if (!quit_comp_thread) { + if (!comp_param[idx].quit) { len = qemu_put_qemu_file(f, comp_param[idx].file); bytes_transferred += len; } @@ -2203,12 +2203,12 @@ static void *do_data_decompress(void *opaque) DecompressParam *param = opaque; unsigned long pagesize; - while (!quit_decomp_thread) { + while (!param->quit) { qemu_mutex_lock(¶m->mutex); - while (!param->start && !quit_decomp_thread) { + while (!param->start && !param->quit) { qemu_cond_wait(¶m->cond, ¶m->mutex); } - if (!quit_decomp_thread) { + if (!param->quit) { pagesize = TARGET_PAGE_SIZE; /* uncompress() will return failed in some case, especially * when the page is dirted when doing the compression, it's @@ -2255,7 +2255,6 @@ void migrate_decompress_threads_create(void) thread_count = migrate_decompress_threads(); decompress_threads = g_new0(QemuThread, thread_count); decomp_param = g_new0(DecompressParam, thread_count); - quit_decomp_thread = false; qemu_mutex_init(&decomp_done_lock); qemu_cond_init(&decomp_done_cond); for (i = 0; i < thread_count; i++) { @@ -2263,6 +2262,7 @@ void migrate_decompress_threads_create(void) qemu_cond_init(&decomp_param[i].cond); decomp_param[i].compbuf = g_malloc0(compressBound(TARGET_PAGE_SIZE)); decomp_param[i].done = true; + decomp_param[i].quit = false; qemu_thread_create(decompress_threads + i, "decompress", do_data_decompress, decomp_param + i, QEMU_THREAD_JOINABLE); @@ -2273,10 +2273,10 @@ void migrate_decompress_threads_join(void) { int i, thread_count; - quit_decomp_thread = true; thread_count = migrate_decompress_threads(); for (i = 0; i < thread_count; i++) { qemu_mutex_lock(&decomp_param[i].mutex); + decomp_param[i].quit = true; qemu_cond_signal(&decomp_param[i].cond); qemu_mutex_unlock(&decomp_param[i].mutex); }