[PATCH v3 14/15] drivers/firmware/sdei: Expose struct sdei_event
Jonathan Cameron
Jonathan.Cameron at Huawei.com
Tue Jul 28 11:48:00 EDT 2020
On Tue, 28 Jul 2020 12:59:54 +1000
Gavin Shan <gshan at redhat.com> wrote:
> This splits struct sdei_event into two structs: sdei_event and
> sdei_internal_event. The former one can be dereferenced from
> external module like arm64/kvm when SDEI virtualization is
> supported. The later one is used by the client driver only.
>
> This shouldn't cause functional changes.
>
> Signed-off-by: Gavin Shan <gshan at redhat.com>
Hi Gavin,
This ended up cleaner than I expected :)
You may have already tried it, but if not it might be worth experimenting with
a bit of naming changing and local variables.
In most places you are operating only on either the
struct sdei_event, or the wrapping struct sdei_internal_event
It may help both readability and size of patch to give naming such as
struct sdei_internal_event *event_el =...;
struct sdei_event *event = &event_el->event;
From eyeballing the code I'm not sure if that's actually beneficial or not.
It is tidier in the various loops over the list, but requires a bunch of
renames elsewhere.
What do you think?
Thanks,
Jonathan
> ---
> v3: Split struct sdei_event into struct sdei_{internal,}_event and
> struct sdei_internal_event is used by client driver only
> ---
> drivers/firmware/arm_sdei.c | 116 ++++++++++++++++++------------------
> include/linux/arm_sdei.h | 6 ++
> 2 files changed, 63 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
> index 2678475940e6..c80085e30db1 100644
> --- a/drivers/firmware/arm_sdei.c
> +++ b/drivers/firmware/arm_sdei.c
> @@ -44,16 +44,14 @@ static asmlinkage void (*sdei_firmware_call)(unsigned long function_id,
> /* entry point from firmware to arch asm code */
> static unsigned long sdei_entry_point;
>
> -struct sdei_event {
> +struct sdei_internal_event {
> + struct sdei_event event;
> +
> /* These three are protected by the sdei_list_lock */
> struct list_head list;
> bool reregister;
> bool reenable;
>
> - u32 event_num;
> - u8 type;
> - u8 priority;
> -
> /* This pointer is handed to firmware as the event argument. */
> union {
> /* Shared events */
> @@ -73,7 +71,7 @@ static LIST_HEAD(sdei_list);
>
> /* Private events are registered/enabled via IPI passing one of these */
> struct sdei_crosscall_args {
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
> atomic_t errors;
> int first_error;
> };
> @@ -86,7 +84,7 @@ struct sdei_crosscall_args {
> } while (0)
>
> static inline int sdei_do_local_call(smp_call_func_t fn,
> - struct sdei_event *event)
> + struct sdei_internal_event *event)
> {
> struct sdei_crosscall_args arg;
>
> @@ -97,7 +95,7 @@ static inline int sdei_do_local_call(smp_call_func_t fn,
> }
>
> static inline int sdei_do_cross_call(smp_call_func_t fn,
> - struct sdei_event *event)
> + struct sdei_internal_event *event)
> {
> struct sdei_crosscall_args arg;
>
> @@ -162,15 +160,15 @@ static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0,
> }
> NOKPROBE_SYMBOL(invoke_sdei_fn);
>
> -static struct sdei_event *sdei_event_find(u32 event_num)
> +static struct sdei_internal_event *sdei_event_find(u32 event_num)
> {
> - struct sdei_event *e, *found = NULL;
> + struct sdei_internal_event *e, *found = NULL;
>
> lockdep_assert_held(&sdei_events_lock);
>
> spin_lock(&sdei_list_lock);
> list_for_each_entry(e, &sdei_list, list) {
> - if (e->event_num == event_num) {
> + if (e->event.event_num == event_num) {
> found = e;
> break;
> }
> @@ -193,13 +191,13 @@ static int sdei_api_event_get_info(u32 event, u32 info, u64 *result)
> 0, 0, result);
> }
>
> -static struct sdei_event *sdei_event_create(u32 event_num,
> - sdei_event_callback *cb,
> - void *cb_arg)
> +static struct sdei_internal_event *sdei_event_create(u32 event_num,
> + sdei_event_callback *cb,
> + void *cb_arg)
> {
> int err;
> u64 result;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
> struct sdei_registered_event *reg;
>
> lockdep_assert_held(&sdei_events_lock);
> @@ -211,29 +209,29 @@ static struct sdei_event *sdei_event_create(u32 event_num,
> }
>
> INIT_LIST_HEAD(&event->list);
> - event->event_num = event_num;
> + event->event.event_num = event_num;
>
> err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY,
> &result);
> if (err)
> goto fail;
> - event->priority = result;
> + event->event.priority = result;
>
> err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE,
> &result);
> if (err)
> goto fail;
> - event->type = result;
> + event->event.type = result;
>
> - if (event->type == SDEI_EVENT_TYPE_SHARED) {
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED) {
> reg = kzalloc(sizeof(*reg), GFP_KERNEL);
> if (!reg) {
> err = -ENOMEM;
> goto fail;
> }
>
> - reg->event_num = event->event_num;
> - reg->priority = event->priority;
> + reg->event_num = event->event.event_num;
> + reg->priority = event->event.priority;
>
> reg->callback = cb;
> reg->callback_arg = cb_arg;
> @@ -251,8 +249,8 @@ static struct sdei_event *sdei_event_create(u32 event_num,
> for_each_possible_cpu(cpu) {
> reg = per_cpu_ptr(regs, cpu);
>
> - reg->event_num = event->event_num;
> - reg->priority = event->priority;
> + reg->event_num = event->event.event_num;
> + reg->priority = event->event.priority;
> reg->callback = cb;
> reg->callback_arg = cb_arg;
> }
> @@ -271,14 +269,14 @@ static struct sdei_event *sdei_event_create(u32 event_num,
> return ERR_PTR(err);
> }
>
> -static void sdei_event_destroy_llocked(struct sdei_event *event)
> +static void sdei_event_destroy_llocked(struct sdei_internal_event *event)
> {
> lockdep_assert_held(&sdei_events_lock);
> lockdep_assert_held(&sdei_list_lock);
>
> list_del(&event->list);
>
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> kfree(event->registered);
> else
> free_percpu(event->private_registered);
> @@ -286,7 +284,7 @@ static void sdei_event_destroy_llocked(struct sdei_event *event)
> kfree(event);
> }
>
> -static void sdei_event_destroy(struct sdei_event *event)
> +static void sdei_event_destroy(struct sdei_internal_event *event)
> {
> spin_lock(&sdei_list_lock);
> sdei_event_destroy_llocked(event);
> @@ -392,7 +390,7 @@ static void _local_event_enable(void *data)
>
> WARN_ON_ONCE(preemptible());
>
> - err = sdei_api_event_enable(arg->event->event_num);
> + err = sdei_api_event_enable(arg->event->event.event_num);
>
> sdei_cross_call_return(arg, err);
> }
> @@ -400,7 +398,7 @@ static void _local_event_enable(void *data)
> int sdei_event_enable(u32 event_num)
> {
> int err = -EINVAL;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> mutex_lock(&sdei_events_lock);
> event = sdei_event_find(event_num);
> @@ -411,8 +409,8 @@ int sdei_event_enable(u32 event_num)
>
>
> cpus_read_lock();
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> - err = sdei_api_event_enable(event->event_num);
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> + err = sdei_api_event_enable(event->event.event_num);
> else
> err = sdei_do_cross_call(_local_event_enable, event);
>
> @@ -438,7 +436,7 @@ static void _ipi_event_disable(void *data)
> int err;
> struct sdei_crosscall_args *arg = data;
>
> - err = sdei_api_event_disable(arg->event->event_num);
> + err = sdei_api_event_disable(arg->event->event.event_num);
>
> sdei_cross_call_return(arg, err);
> }
> @@ -446,7 +444,7 @@ static void _ipi_event_disable(void *data)
> int sdei_event_disable(u32 event_num)
> {
> int err = -EINVAL;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> mutex_lock(&sdei_events_lock);
> event = sdei_event_find(event_num);
> @@ -459,8 +457,8 @@ int sdei_event_disable(u32 event_num)
> event->reenable = false;
> spin_unlock(&sdei_list_lock);
>
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> - err = sdei_api_event_disable(event->event_num);
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> + err = sdei_api_event_disable(event->event.event_num);
> else
> err = sdei_do_cross_call(_ipi_event_disable, event);
> mutex_unlock(&sdei_events_lock);
> @@ -482,7 +480,7 @@ static void _local_event_unregister(void *data)
>
> WARN_ON_ONCE(preemptible());
>
> - err = sdei_api_event_unregister(arg->event->event_num);
> + err = sdei_api_event_unregister(arg->event->event.event_num);
>
> sdei_cross_call_return(arg, err);
> }
> @@ -490,7 +488,7 @@ static void _local_event_unregister(void *data)
> int sdei_event_unregister(u32 event_num)
> {
> int err;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> WARN_ON(in_nmi());
>
> @@ -507,8 +505,8 @@ int sdei_event_unregister(u32 event_num)
> event->reenable = false;
> spin_unlock(&sdei_list_lock);
>
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> - err = sdei_api_event_unregister(event->event_num);
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> + err = sdei_api_event_unregister(event->event.event_num);
> else
> err = sdei_do_cross_call(_local_event_unregister, event);
>
> @@ -529,15 +527,15 @@ int sdei_event_unregister(u32 event_num)
> static int sdei_unregister_shared(void)
> {
> int err = 0;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> mutex_lock(&sdei_events_lock);
> spin_lock(&sdei_list_lock);
> list_for_each_entry(event, &sdei_list, list) {
> - if (event->type != SDEI_EVENT_TYPE_SHARED)
> + if (event->event.type != SDEI_EVENT_TYPE_SHARED)
> continue;
>
> - err = sdei_api_event_unregister(event->event_num);
> + err = sdei_api_event_unregister(event->event.event_num);
> if (err)
> break;
> }
> @@ -565,8 +563,8 @@ static void _local_event_register(void *data)
> WARN_ON(preemptible());
>
> reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id());
> - err = sdei_api_event_register(arg->event->event_num, sdei_entry_point,
> - reg, 0, 0);
> + err = sdei_api_event_register(arg->event->event.event_num,
> + sdei_entry_point, reg, 0, 0);
>
> sdei_cross_call_return(arg, err);
> }
> @@ -574,7 +572,7 @@ static void _local_event_register(void *data)
> int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg)
> {
> int err;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> WARN_ON(in_nmi());
>
> @@ -593,8 +591,8 @@ int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg)
> }
>
> cpus_read_lock();
> - if (event->type == SDEI_EVENT_TYPE_SHARED) {
> - err = sdei_api_event_register(event->event_num,
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED) {
> + err = sdei_api_event_register(event->event.event_num,
> sdei_entry_point,
> event->registered,
> SDEI_EVENT_REGISTER_RM_ANY, 0);
> @@ -623,31 +621,31 @@ int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg)
> static int sdei_reregister_shared(void)
> {
> int err = 0;
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
>
> mutex_lock(&sdei_events_lock);
> spin_lock(&sdei_list_lock);
> list_for_each_entry(event, &sdei_list, list) {
Perhaps worth a local variable for event->event?
If you were to do
list_for_each_entry(event_el, &sdei_list, list) {
sdei_event *event = &event_el->event;
Would reduce the patch size and might give slightly more readable code.
The issue is that you'd then need to be very careful with naming of
event vs event_el (for element of list) to keep it consistent.
It's possible it will cause more mess than the current approach!
> - if (event->type != SDEI_EVENT_TYPE_SHARED)
> + if (event->event.type != SDEI_EVENT_TYPE_SHARED)
> continue;
>
> if (event->reregister) {
> - err = sdei_api_event_register(event->event_num,
> + err = sdei_api_event_register(event->event.event_num,
> sdei_entry_point, event->registered,
> SDEI_EVENT_REGISTER_RM_ANY, 0);
> if (err) {
> sdei_event_destroy_llocked(event);
> pr_err("Failed to re-register event %u\n",
> - event->event_num);
> + event->event.event_num);
> break;
> }
> }
>
> if (event->reenable) {
> - err = sdei_api_event_enable(event->event_num);
> + err = sdei_api_event_enable(event->event.event_num);
> if (err) {
> pr_err("Failed to re-enable event %u\n",
> - event->event_num);
> + event->event.event_num);
> break;
> }
> }
> @@ -660,19 +658,19 @@ static int sdei_reregister_shared(void)
>
> static int sdei_cpuhp_down(unsigned int cpu)
> {
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
> int err;
>
> /* un-register private events */
> spin_lock(&sdei_list_lock);
> list_for_each_entry(event, &sdei_list, list) {
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> continue;
>
> err = sdei_do_local_call(_local_event_unregister, event);
> if (err) {
> pr_err("Failed to unregister event %u: %d\n",
> - event->event_num, err);
> + event->event.event_num, err);
> }
> }
> spin_unlock(&sdei_list_lock);
> @@ -682,20 +680,20 @@ static int sdei_cpuhp_down(unsigned int cpu)
>
> static int sdei_cpuhp_up(unsigned int cpu)
> {
> - struct sdei_event *event;
> + struct sdei_internal_event *event;
> int err;
>
> /* re-register/enable private events */
> spin_lock(&sdei_list_lock);
> list_for_each_entry(event, &sdei_list, list) {
> - if (event->type == SDEI_EVENT_TYPE_SHARED)
> + if (event->event.type == SDEI_EVENT_TYPE_SHARED)
> continue;
>
> if (event->reregister) {
> err = sdei_do_local_call(_local_event_register, event);
> if (err) {
> pr_err("Failed to re-register event %u: %d\n",
> - event->event_num, err);
> + event->event.event_num, err);
> }
> }
>
> @@ -703,7 +701,7 @@ static int sdei_cpuhp_up(unsigned int cpu)
> err = sdei_do_local_call(_local_event_enable, event);
> if (err) {
> pr_err("Failed to re-enable event %u: %d\n",
> - event->event_num, err);
> + event->event.event_num, err);
> }
> }
> }
> diff --git a/include/linux/arm_sdei.h b/include/linux/arm_sdei.h
> index 0a241c5c911d..d2464a18b6ff 100644
> --- a/include/linux/arm_sdei.h
> +++ b/include/linux/arm_sdei.h
> @@ -22,6 +22,12 @@
> */
> typedef int (sdei_event_callback)(u32 event, struct pt_regs *regs, void *arg);
>
> +struct sdei_event {
> + u32 event_num;
> + u8 type;
> + u8 priority;
> +};
> +
> /*
> * Register your callback to claim an event. The event must be described
> * by firmware.
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