From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58552) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gDJFO-0004U7-TZ for qemu-devel@nongnu.org; Thu, 18 Oct 2018 21:06:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gDJFL-0002k5-CK for qemu-devel@nongnu.org; Thu, 18 Oct 2018 21:06:38 -0400 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:53739) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gDJFJ-0002aD-D5 for qemu-devel@nongnu.org; Thu, 18 Oct 2018 21:06:35 -0400 From: "Emilio G. Cota" Date: Thu, 18 Oct 2018 21:05:30 -0400 Message-Id: <20181019010625.25294-2-cota@braap.org> In-Reply-To: <20181019010625.25294-1-cota@braap.org> References: <20181019010625.25294-1-cota@braap.org> Subject: [Qemu-devel] [RFC v3 01/56] cpu: convert queued work to a QSIMPLEQ List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Paolo Bonzini , Peter Crosthwaite , Richard Henderson Instead of open-coding it. While at it, make sure that all accesses to the list are performed while holding the list's lock. Cc: Peter Crosthwaite Cc: Richard Henderson Signed-off-by: Emilio G. Cota --- include/qom/cpu.h | 6 +++--- cpus-common.c | 25 ++++++++----------------- cpus.c | 14 ++++++++++++-- qom/cpu.c | 1 + 4 files changed, 24 insertions(+), 22 deletions(-) diff --git a/include/qom/cpu.h b/include/qom/cpu.h index dc130cd307..53488b202f 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -315,8 +315,8 @@ struct qemu_work_item; * @mem_io_pc: Host Program Counter at which the memory was accessed. * @mem_io_vaddr: Target virtual address at which the memory was accessed. * @kvm_fd: vCPU file descriptor for KVM. - * @work_mutex: Lock to prevent multiple access to queued_work_*. - * @queued_work_first: First asynchronous work pending. + * @work_mutex: Lock to prevent multiple access to @work_list. + * @work_list: List of pending asynchronous work. * @trace_dstate_delayed: Delayed changes to trace_dstate (includes all changes * to @trace_dstate). * @trace_dstate: Dynamic tracing state of events for this vCPU (bitmask). @@ -357,7 +357,7 @@ struct CPUState { sigjmp_buf jmp_env; QemuMutex work_mutex; - struct qemu_work_item *queued_work_first, *queued_work_last; + QSIMPLEQ_HEAD(, qemu_work_item) work_list; CPUAddressSpace *cpu_ases; int num_ases; diff --git a/cpus-common.c b/cpus-common.c index 98dd8c6ff1..a2a6cd93a1 100644 --- a/cpus-common.c +++ b/cpus-common.c @@ -107,7 +107,7 @@ void cpu_list_remove(CPUState *cpu) } struct qemu_work_item { - struct qemu_work_item *next; + QSIMPLEQ_ENTRY(qemu_work_item) node; run_on_cpu_func func; run_on_cpu_data data; bool free, exclusive, done; @@ -116,13 +116,7 @@ struct qemu_work_item { static void queue_work_on_cpu(CPUState *cpu, struct qemu_work_item *wi) { qemu_mutex_lock(&cpu->work_mutex); - if (cpu->queued_work_first == NULL) { - cpu->queued_work_first = wi; - } else { - cpu->queued_work_last->next = wi; - } - cpu->queued_work_last = wi; - wi->next = NULL; + QSIMPLEQ_INSERT_TAIL(&cpu->work_list, wi, node); wi->done = false; qemu_mutex_unlock(&cpu->work_mutex); @@ -314,17 +308,14 @@ void process_queued_cpu_work(CPUState *cpu) { struct qemu_work_item *wi; - if (cpu->queued_work_first == NULL) { + qemu_mutex_lock(&cpu->work_mutex); + if (QSIMPLEQ_EMPTY(&cpu->work_list)) { + qemu_mutex_unlock(&cpu->work_mutex); return; } - - qemu_mutex_lock(&cpu->work_mutex); - while (cpu->queued_work_first != NULL) { - wi = cpu->queued_work_first; - cpu->queued_work_first = wi->next; - if (!cpu->queued_work_first) { - cpu->queued_work_last = NULL; - } + while (!QSIMPLEQ_EMPTY(&cpu->work_list)) { + wi = QSIMPLEQ_FIRST(&cpu->work_list); + QSIMPLEQ_REMOVE_HEAD(&cpu->work_list, node); qemu_mutex_unlock(&cpu->work_mutex); if (wi->exclusive) { /* Running work items outside the BQL avoids the following deadlock: diff --git a/cpus.c b/cpus.c index cce64874e6..6d86522031 100644 --- a/cpus.c +++ b/cpus.c @@ -88,9 +88,19 @@ bool cpu_is_stopped(CPUState *cpu) return cpu->stopped || !runstate_is_running(); } +static inline bool cpu_work_list_empty(CPUState *cpu) +{ + bool ret; + + qemu_mutex_lock(&cpu->work_mutex); + ret = QSIMPLEQ_EMPTY(&cpu->work_list); + qemu_mutex_unlock(&cpu->work_mutex); + return ret; +} + static bool cpu_thread_is_idle(CPUState *cpu) { - if (cpu->stop || cpu->queued_work_first) { + if (cpu->stop || !cpu_work_list_empty(cpu)) { return false; } if (cpu_is_stopped(cpu)) { @@ -1509,7 +1519,7 @@ static void *qemu_tcg_rr_cpu_thread_fn(void *arg) cpu = first_cpu; } - while (cpu && !cpu->queued_work_first && !cpu->exit_request) { + while (cpu && cpu_work_list_empty(cpu) && !cpu->exit_request) { atomic_mb_set(&tcg_current_rr_cpu, cpu); current_cpu = cpu; diff --git a/qom/cpu.c b/qom/cpu.c index 20ad54d43f..c47169896e 100644 --- a/qom/cpu.c +++ b/qom/cpu.c @@ -373,6 +373,7 @@ static void cpu_common_initfn(Object *obj) cpu->nr_threads = 1; qemu_mutex_init(&cpu->work_mutex); + QSIMPLEQ_INIT(&cpu->work_list); QTAILQ_INIT(&cpu->breakpoints); QTAILQ_INIT(&cpu->watchpoints); -- 2.17.1