Refactor the memory prealloc threads support: - Make memset context a global qlist - Move the memset thread join/cleanup code to a separate routine
This is functionally equivalent and facilitates multiple memset contexts (used in a subsequent patch). Signed-off-by: Mark Kanda <mark.ka...@oracle.com> --- util/oslib-posix.c | 90 ++++++++++++++++++++++++++++++---------------- 1 file changed, 60 insertions(+), 30 deletions(-) diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 7c297003b9..26bf2f2883 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -63,11 +63,15 @@ struct MemsetThread; +static QLIST_HEAD(, MemsetContext) memset_contexts = + QLIST_HEAD_INITIALIZER(memset_contexts); + typedef struct MemsetContext { bool all_threads_created; bool any_thread_failed; struct MemsetThread *threads; int num_threads; + QLIST_ENTRY(MemsetContext) next; } MemsetContext; struct MemsetThread { @@ -417,14 +421,15 @@ static int touch_all_pages(char *area, size_t hpagesize, size_t numpages, bool use_madv_populate_write) { static gsize initialized = 0; - MemsetContext context = { - .num_threads = get_memset_num_threads(hpagesize, numpages, max_threads), - }; + MemsetContext *context = g_malloc0(sizeof(MemsetContext)); size_t numpages_per_thread, leftover; void *(*touch_fn)(void *); - int ret = 0, i = 0; + int i = 0; char *addr = area; + context->num_threads = + get_memset_num_threads(hpagesize, numpages, max_threads); + if (g_once_init_enter(&initialized)) { qemu_mutex_init(&page_mutex); qemu_cond_init(&page_cond); @@ -433,7 +438,7 @@ static int touch_all_pages(char *area, size_t hpagesize, size_t numpages, if (use_madv_populate_write) { /* Avoid creating a single thread for MADV_POPULATE_WRITE */ - if (context.num_threads == 1) { + if (context->num_threads == 1) { if (qemu_madvise(area, hpagesize * numpages, QEMU_MADV_POPULATE_WRITE)) { return -errno; @@ -445,49 +450,65 @@ static int touch_all_pages(char *area, size_t hpagesize, size_t numpages, touch_fn = do_touch_pages; } - context.threads = g_new0(MemsetThread, context.num_threads); - numpages_per_thread = numpages / context.num_threads; - leftover = numpages % context.num_threads; - for (i = 0; i < context.num_threads; i++) { - context.threads[i].addr = addr; - context.threads[i].numpages = numpages_per_thread + (i < leftover); - context.threads[i].hpagesize = hpagesize; - context.threads[i].context = &context; + context->threads = g_new0(MemsetThread, context->num_threads); + numpages_per_thread = numpages / context->num_threads; + leftover = numpages % context->num_threads; + for (i = 0; i < context->num_threads; i++) { + context->threads[i].addr = addr; + context->threads[i].numpages = numpages_per_thread + (i < leftover); + context->threads[i].hpagesize = hpagesize; + context->threads[i].context = context; if (tc) { - thread_context_create_thread(tc, &context.threads[i].pgthread, + thread_context_create_thread(tc, &context->threads[i].pgthread, "touch_pages", - touch_fn, &context.threads[i], + touch_fn, &context->threads[i], QEMU_THREAD_JOINABLE); } else { - qemu_thread_create(&context.threads[i].pgthread, "touch_pages", - touch_fn, &context.threads[i], + qemu_thread_create(&context->threads[i].pgthread, "touch_pages", + touch_fn, &context->threads[i], QEMU_THREAD_JOINABLE); } - addr += context.threads[i].numpages * hpagesize; + addr += context->threads[i].numpages * hpagesize; } if (!use_madv_populate_write) { - sigbus_memset_context = &context; + sigbus_memset_context = context; + } + + QLIST_INSERT_HEAD(&memset_contexts, context, next); + + return 0; +} + +static int wait_mem_prealloc(void) +{ + int i, ret = 0; + MemsetContext *context, *next_context; + + if (QLIST_EMPTY(&memset_contexts)) { + return ret; } qemu_mutex_lock(&page_mutex); - context.all_threads_created = true; + QLIST_FOREACH(context, &memset_contexts, next) { + context->all_threads_created = true; + } qemu_cond_broadcast(&page_cond); qemu_mutex_unlock(&page_mutex); - for (i = 0; i < context.num_threads; i++) { - int tmp = (uintptr_t)qemu_thread_join(&context.threads[i].pgthread); + QLIST_FOREACH_SAFE(context, &memset_contexts, next, next_context) { + for (i = 0; i < context->num_threads; i++) { + int tmp = + (uintptr_t)qemu_thread_join(&context->threads[i].pgthread); - if (tmp) { - ret = tmp; + if (tmp) { + ret = tmp; + } } + QLIST_REMOVE(context, next); + g_free(context->threads); + g_free(context); } - - if (!use_madv_populate_write) { - sigbus_memset_context = NULL; - } - g_free(context.threads); - return ret; } @@ -546,8 +567,16 @@ bool qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, error_setg_errno(errp, -ret, "qemu_prealloc_mem: preallocating memory failed"); rv = false; + goto err; } + ret = wait_mem_prealloc(); + if (ret) { + error_setg_errno(errp, -ret, + "qemu_prealloc_mem: failed waiting for memory prealloc"); + rv = false; + } +err: if (!use_madv_populate_write) { ret = sigaction(SIGBUS, &sigbus_oldact, NULL); if (ret) { @@ -556,6 +585,7 @@ bool qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, exit(1); } qemu_mutex_unlock(&sigbus_mutex); + sigbus_memset_context = NULL; } return rv; } -- 2.39.3