| Message ID | 20200326193156.4322-3-robert.foley@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | per-CPU locks | expand |
Robert Foley <robert.foley@linaro.org> writes: > From: "Emilio G. Cota" <cota@braap.org> > > This lock will soon protect more fields of the struct. Give > it a more appropriate name. Hmm while bisecting to find another problem I found this commit: /home/alex/lsrc/qemu.git/hw/core/cpu.c: In function ‘cpu_common_finalize’: /home/alex/lsrc/qemu.git/hw/core/cpu.c:383:27: error: incompatible type for argument 1 of ‘qemu_mutex_destroy’ qemu_mutex_destroy(cpu->lock); ~~~^~~~~~ In file included from /home/alex/lsrc/qemu.git/include/hw/core/cpu.h:31, from /home/alex/lsrc/qemu.git/hw/core/cpu.c:23: /home/alex/lsrc/qemu.git/include/qemu/thread.h:26:36: note: expected ‘QemuMutex *’ {aka ‘struct QemuMutex *’} but argument is of type ‘QemuMutex’ {aka ‘struct QemuMutex’} void qemu_mutex_destroy(QemuMutex *mutex); ~~~~~~~~~~~^~~~~ make: *** [/home/alex/lsrc/qemu.git/rules.mak:69: hw/core/cpu.o] Error 1 which works fine in the final product so I suspect something has slipped between commits somewhere. > > Reviewed-by: Richard Henderson <richard.henderson@linaro.org> > Reviewed-by: Alex Bennée <alex.bennee@linaro.org> > Signed-off-by: Emilio G. Cota <cota@braap.org> > Signed-off-by: Robert Foley <robert.foley@linaro.org> > --- > cpus-common.c | 14 +++++++------- > cpus.c | 4 ++-- > hw/core/cpu.c | 4 ++-- > include/hw/core/cpu.h | 6 ++++-- > 4 files changed, 15 insertions(+), 13 deletions(-) > > diff --git a/cpus-common.c b/cpus-common.c > index 3d659df464..f75cae23d9 100644 > --- a/cpus-common.c > +++ b/cpus-common.c > @@ -107,10 +107,10 @@ struct qemu_work_item { > > static void queue_work_on_cpu(CPUState *cpu, struct qemu_work_item *wi) > { > - qemu_mutex_lock(&cpu->work_mutex); > + qemu_mutex_lock(&cpu->lock); > QSIMPLEQ_INSERT_TAIL(&cpu->work_list, wi, node); > wi->done = false; > - qemu_mutex_unlock(&cpu->work_mutex); > + qemu_mutex_unlock(&cpu->lock); > > qemu_cpu_kick(cpu); > } > @@ -304,15 +304,15 @@ void process_queued_cpu_work(CPUState *cpu) > { > struct qemu_work_item *wi; > > - qemu_mutex_lock(&cpu->work_mutex); > + qemu_mutex_lock(&cpu->lock); > if (QSIMPLEQ_EMPTY(&cpu->work_list)) { > - qemu_mutex_unlock(&cpu->work_mutex); > + qemu_mutex_unlock(&cpu->lock); > return; > } > 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); > + qemu_mutex_unlock(&cpu->lock); > if (wi->exclusive) { > /* Running work items outside the BQL avoids the following deadlock: > * 1) start_exclusive() is called with the BQL taken while another > @@ -328,13 +328,13 @@ void process_queued_cpu_work(CPUState *cpu) > } else { > wi->func(cpu, wi->data); > } > - qemu_mutex_lock(&cpu->work_mutex); > + qemu_mutex_lock(&cpu->lock); > if (wi->free) { > g_free(wi); > } else { > atomic_mb_set(&wi->done, true); > } > } > - qemu_mutex_unlock(&cpu->work_mutex); > + qemu_mutex_unlock(&cpu->lock); > qemu_cond_broadcast(&qemu_work_cond); > } > diff --git a/cpus.c b/cpus.c > index 151abbc04c..71bd2f5d55 100644 > --- a/cpus.c > +++ b/cpus.c > @@ -100,9 +100,9 @@ static inline bool cpu_work_list_empty(CPUState *cpu) > { > bool ret; > > - qemu_mutex_lock(&cpu->work_mutex); > + qemu_mutex_lock(&cpu->lock); > ret = QSIMPLEQ_EMPTY(&cpu->work_list); > - qemu_mutex_unlock(&cpu->work_mutex); > + qemu_mutex_unlock(&cpu->lock); > return ret; > } > > diff --git a/hw/core/cpu.c b/hw/core/cpu.c > index 2fc6aa2159..bc0416829a 100644 > --- a/hw/core/cpu.c > +++ b/hw/core/cpu.c > @@ -367,7 +367,7 @@ static void cpu_common_initfn(Object *obj) > cpu->nr_cores = 1; > cpu->nr_threads = 1; > > - qemu_mutex_init(&cpu->work_mutex); > + qemu_mutex_init(&cpu->lock); > QSIMPLEQ_INIT(&cpu->work_list); > QTAILQ_INIT(&cpu->breakpoints); > QTAILQ_INIT(&cpu->watchpoints); > @@ -379,7 +379,7 @@ static void cpu_common_finalize(Object *obj) > { > CPUState *cpu = CPU(obj); > > - qemu_mutex_destroy(&cpu->work_mutex); > + qemu_mutex_destroy(cpu->lock); > } > > static int64_t cpu_common_get_arch_id(CPUState *cpu) > diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h > index 398b65159e..0b75fdb093 100644 > --- a/include/hw/core/cpu.h > +++ b/include/hw/core/cpu.h > @@ -331,7 +331,8 @@ struct qemu_work_item; > * @opaque: User data. > * @mem_io_pc: Host Program Counter at which the memory was accessed. > * @kvm_fd: vCPU file descriptor for KVM. > - * @work_mutex: Lock to prevent multiple access to @work_list. > + * @lock: Lock to prevent multiple access to per-CPU fields. Must be acquired > + * after the BQL. > * @work_list: List of pending asynchronous work. > * @trace_dstate_delayed: Delayed changes to trace_dstate (includes all changes > * to @trace_dstate). > @@ -375,7 +376,8 @@ struct CPUState { > uint64_t random_seed; > sigjmp_buf jmp_env; > > - QemuMutex work_mutex; > + QemuMutex lock; > + /* fields below protected by @lock */ > QSIMPLEQ_HEAD(, qemu_work_item) work_list; > > CPUAddressSpace *cpu_ases; -- Alex Bennée
On Mon, 11 May 2020 at 10:48, Alex Bennée <alex.bennee@linaro.org> wrote: > Hmm while bisecting to find another problem I found this commit: > > /home/alex/lsrc/qemu.git/hw/core/cpu.c: In function ‘cpu_common_finalize’: > /home/alex/lsrc/qemu.git/hw/core/cpu.c:383:27: error: incompatible type for argument 1 of ‘qemu_mutex_destroy’ > qemu_mutex_destroy(cpu->lock); > ~~~^~~~~~ > In file included from /home/alex/lsrc/qemu.git/include/hw/core/cpu.h:31, > from /home/alex/lsrc/qemu.git/hw/core/cpu.c:23: > /home/alex/lsrc/qemu.git/include/qemu/thread.h:26:36: note: expected ‘QemuMutex *’ {aka ‘struct QemuMutex *’} but argument is of type ‘QemuMutex’ {aka ‘struct QemuMutex’} > void qemu_mutex_destroy(QemuMutex *mutex); > ~~~~~~~~~~~^~~~~ > make: *** [/home/alex/lsrc/qemu.git/rules.mak:69: hw/core/cpu.o] Error 1 > > which works fine in the final product so I suspect something has slipped > between commits somewhere. I agree, looks like something is off with the intermediate commits. Thanks for noticing it ! Will fix it. Thanks, -Rob
diff --git a/cpus-common.c b/cpus-common.c index 3d659df464..f75cae23d9 100644 --- a/cpus-common.c +++ b/cpus-common.c @@ -107,10 +107,10 @@ struct qemu_work_item { static void queue_work_on_cpu(CPUState *cpu, struct qemu_work_item *wi) { - qemu_mutex_lock(&cpu->work_mutex); + qemu_mutex_lock(&cpu->lock); QSIMPLEQ_INSERT_TAIL(&cpu->work_list, wi, node); wi->done = false; - qemu_mutex_unlock(&cpu->work_mutex); + qemu_mutex_unlock(&cpu->lock); qemu_cpu_kick(cpu); } @@ -304,15 +304,15 @@ void process_queued_cpu_work(CPUState *cpu) { struct qemu_work_item *wi; - qemu_mutex_lock(&cpu->work_mutex); + qemu_mutex_lock(&cpu->lock); if (QSIMPLEQ_EMPTY(&cpu->work_list)) { - qemu_mutex_unlock(&cpu->work_mutex); + qemu_mutex_unlock(&cpu->lock); return; } 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); + qemu_mutex_unlock(&cpu->lock); if (wi->exclusive) { /* Running work items outside the BQL avoids the following deadlock: * 1) start_exclusive() is called with the BQL taken while another @@ -328,13 +328,13 @@ void process_queued_cpu_work(CPUState *cpu) } else { wi->func(cpu, wi->data); } - qemu_mutex_lock(&cpu->work_mutex); + qemu_mutex_lock(&cpu->lock); if (wi->free) { g_free(wi); } else { atomic_mb_set(&wi->done, true); } } - qemu_mutex_unlock(&cpu->work_mutex); + qemu_mutex_unlock(&cpu->lock); qemu_cond_broadcast(&qemu_work_cond); } diff --git a/cpus.c b/cpus.c index 151abbc04c..71bd2f5d55 100644 --- a/cpus.c +++ b/cpus.c @@ -100,9 +100,9 @@ static inline bool cpu_work_list_empty(CPUState *cpu) { bool ret; - qemu_mutex_lock(&cpu->work_mutex); + qemu_mutex_lock(&cpu->lock); ret = QSIMPLEQ_EMPTY(&cpu->work_list); - qemu_mutex_unlock(&cpu->work_mutex); + qemu_mutex_unlock(&cpu->lock); return ret; } diff --git a/hw/core/cpu.c b/hw/core/cpu.c index 2fc6aa2159..bc0416829a 100644 --- a/hw/core/cpu.c +++ b/hw/core/cpu.c @@ -367,7 +367,7 @@ static void cpu_common_initfn(Object *obj) cpu->nr_cores = 1; cpu->nr_threads = 1; - qemu_mutex_init(&cpu->work_mutex); + qemu_mutex_init(&cpu->lock); QSIMPLEQ_INIT(&cpu->work_list); QTAILQ_INIT(&cpu->breakpoints); QTAILQ_INIT(&cpu->watchpoints); @@ -379,7 +379,7 @@ static void cpu_common_finalize(Object *obj) { CPUState *cpu = CPU(obj); - qemu_mutex_destroy(&cpu->work_mutex); + qemu_mutex_destroy(cpu->lock); } static int64_t cpu_common_get_arch_id(CPUState *cpu) diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h index 398b65159e..0b75fdb093 100644 --- a/include/hw/core/cpu.h +++ b/include/hw/core/cpu.h @@ -331,7 +331,8 @@ struct qemu_work_item; * @opaque: User data. * @mem_io_pc: Host Program Counter at which the memory was accessed. * @kvm_fd: vCPU file descriptor for KVM. - * @work_mutex: Lock to prevent multiple access to @work_list. + * @lock: Lock to prevent multiple access to per-CPU fields. Must be acquired + * after the BQL. * @work_list: List of pending asynchronous work. * @trace_dstate_delayed: Delayed changes to trace_dstate (includes all changes * to @trace_dstate). @@ -375,7 +376,8 @@ struct CPUState { uint64_t random_seed; sigjmp_buf jmp_env; - QemuMutex work_mutex; + QemuMutex lock; + /* fields below protected by @lock */ QSIMPLEQ_HEAD(, qemu_work_item) work_list; CPUAddressSpace *cpu_ases;