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[Qemu-devel] [RFC v4 67/71] cpus-common: release BQL earlier in run_on_c
From: |
Emilio G. Cota |
Subject: |
[Qemu-devel] [RFC v4 67/71] cpus-common: release BQL earlier in run_on_cpu |
Date: |
Thu, 25 Oct 2018 10:46:40 -0400 |
After completing the conversion to per-CPU locks, there is no need
to release the BQL after having called cpu_kick.
Signed-off-by: Emilio G. Cota <address@hidden>
---
cpus-common.c | 20 +++++---------------
1 file changed, 5 insertions(+), 15 deletions(-)
diff --git a/cpus-common.c b/cpus-common.c
index c2ad554d54..80d7e300eb 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -145,6 +145,11 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func,
run_on_cpu_data data)
return;
}
+ /* We are going to sleep on the CPU lock, so release the BQL */
+ if (has_bql) {
+ qemu_mutex_unlock_iothread();
+ }
+
wi.func = func;
wi.data = data;
wi.done = false;
@@ -153,21 +158,6 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func,
run_on_cpu_data data)
cpu_mutex_lock(cpu);
queue_work_on_cpu_locked(cpu, &wi);
-
- /*
- * We are going to sleep on the CPU lock, so release the BQL.
- *
- * During the transition to per-CPU locks, we release the BQL _after_
- * having kicked the destination CPU (from queue_work_on_cpu_locked above).
- * This makes sure that the enqueued work will be seen by the CPU
- * after being woken up from the kick, since the CPU sleeps on the BQL.
- * Once we complete the transition to per-CPU locks, we will release
- * the BQL earlier in this function.
- */
- if (has_bql) {
- qemu_mutex_unlock_iothread();
- }
-
while (!atomic_mb_read(&wi.done)) {
CPUState *self_cpu = current_cpu;
--
2.17.1
- [Qemu-devel] [RFC v4 01/71] cpu: convert queued work to a QSIMPLEQ, Emilio G. Cota, 2018/10/25
- [Qemu-devel] [RFC v4 71/71] cpus-common: wait on the CPU lock for exclusive work completion, Emilio G. Cota, 2018/10/25
- [Qemu-devel] [RFC v4 67/71] cpus-common: release BQL earlier in run_on_cpu,
Emilio G. Cota <=
- [Qemu-devel] [RFC v4 57/71] accel/tcg: convert to cpu_interrupt_request, Emilio G. Cota, 2018/10/25
- [Qemu-devel] [RFC v4 61/71] mips: convert to cpu_has_work_with_iothread_lock, Emilio G. Cota, 2018/10/25
- [Qemu-devel] [RFC v4 65/71] xtensa: convert to cpu_has_work_with_iothread_lock, Emilio G. Cota, 2018/10/25
- [Qemu-devel] [RFC v4 64/71] sparc: convert to cpu_has_work_with_iothread_lock, Emilio G. Cota, 2018/10/25