From e37aee93bf3f9d2e31ae324edee9610da79814af Mon Sep 17 00:00:00 2001 From: Felix Kuehling Date: Fri, 27 Oct 2017 19:35:22 -0400 Subject: [PATCH 3366/4131] drm/amdkfd: Clean up kfd_wait_on_events Cleaned up the code while resolving some potential bugs and inconsistencies in the process. Clean-ups: * Remove enum kfd_event_wait_result, which duplicates KFD_IOC_EVENT_RESULT definitions * alloc_event_waiters can be called without holding p->event_mutex * Return an error code from copy_signaled_event_data instead of bool * Clean up error handling code paths to minimize duplication in kfd_wait_on_events Fixes: * Consistently return an error code from kfd_wait_on_events and set wait_result to KFD_IOC_WAIT_RESULT_FAIL in all failure cases. * Always call free_waiters while holding p->event_mutex * copy_signaled_event_data might sleep. Don't call it while the task state is TASK_INTERRUPTIBLE. Signed-off-by: Felix Kuehling Acked-by: Oded Gabbay Signed-off-by: Oded Gabbay --- drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 5 +-- drivers/gpu/drm/amd/amdkfd/kfd_events.c | 71 ++++++++++++++------------------ drivers/gpu/drm/amd/amdkfd/kfd_priv.h | 8 +--- 3 files changed, 32 insertions(+), 52 deletions(-) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c index 0ef82b2..a25321f 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c @@ -835,15 +835,12 @@ static int kfd_ioctl_wait_events(struct file *filp, struct kfd_process *p, void *data) { struct kfd_ioctl_wait_events_args *args = data; - enum kfd_event_wait_result wait_result; int err; err = kfd_wait_on_events(p, args->num_events, (void __user *)args->events_ptr, (args->wait_for_all != 0), - args->timeout, &wait_result); - - args->wait_result = wait_result; + args->timeout, &args->wait_result); return err; } diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c index 1efd6a8..33cafbb 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c @@ -668,7 +668,7 @@ static bool test_event_condition(bool all, uint32_t num_events, * Copy event specific data, if defined. * Currently only memory exception events have additional data to copy to user */ -static bool copy_signaled_event_data(uint32_t num_events, +static int copy_signaled_event_data(uint32_t num_events, struct kfd_event_waiter *event_waiters, struct kfd_event_data __user *data) { @@ -686,11 +686,11 @@ static bool copy_signaled_event_data(uint32_t num_events, src = &event->memory_exception_data; if (copy_to_user(dst, src, sizeof(struct kfd_hsa_memory_exception_data))) - return false; + return -EFAULT; } } - return true; + return 0; } @@ -727,7 +727,7 @@ static void free_waiters(uint32_t num_events, struct kfd_event_waiter *waiters) int kfd_wait_on_events(struct kfd_process *p, uint32_t num_events, void __user *data, bool all, uint32_t user_timeout_ms, - enum kfd_event_wait_result *wait_result) + uint32_t *wait_result) { struct kfd_event_data __user *events = (struct kfd_event_data __user *) data; @@ -737,18 +737,18 @@ int kfd_wait_on_events(struct kfd_process *p, struct kfd_event_waiter *event_waiters = NULL; long timeout = user_timeout_to_jiffies(user_timeout_ms); + event_waiters = alloc_event_waiters(num_events); + if (!event_waiters) { + ret = -ENOMEM; + goto out; + } + mutex_lock(&p->event_mutex); /* Set to something unreasonable - this is really * just a bool for now. */ - *wait_result = KFD_WAIT_TIMEOUT; - - event_waiters = alloc_event_waiters(num_events); - if (!event_waiters) { - ret = -ENOMEM; - goto fail; - } + *wait_result = KFD_IOC_WAIT_RESULT_TIMEOUT; for (i = 0; i < num_events; i++) { struct kfd_event_data event_data; @@ -756,23 +756,21 @@ int kfd_wait_on_events(struct kfd_process *p, if (copy_from_user(&event_data, &events[i], sizeof(struct kfd_event_data))) { ret = -EFAULT; - goto fail; + goto out_unlock; } ret = init_event_waiter_get_status(p, &event_waiters[i], event_data.event_id, i); if (ret) - goto fail; + goto out_unlock; } /* Check condition once. */ if (test_event_condition(all, num_events, event_waiters)) { - if (copy_signaled_event_data(num_events, - event_waiters, events)) - *wait_result = KFD_WAIT_COMPLETE; - else - *wait_result = KFD_WAIT_ERROR; - free_waiters(num_events, event_waiters); + *wait_result = KFD_IOC_WAIT_RESULT_COMPLETE; + ret = copy_signaled_event_data(num_events, + event_waiters, events); + goto out_unlock; } else { /* Add to wait lists if we need to wait. */ for (i = 0; i < num_events; i++) @@ -781,12 +779,6 @@ int kfd_wait_on_events(struct kfd_process *p, mutex_unlock(&p->event_mutex); - /* Return if all waits were already satisfied. */ - if (*wait_result != KFD_WAIT_TIMEOUT) { - __set_current_state(TASK_RUNNING); - return ret; - } - while (true) { if (fatal_signal_pending(current)) { ret = -EINTR; @@ -818,16 +810,12 @@ int kfd_wait_on_events(struct kfd_process *p, set_current_state(TASK_INTERRUPTIBLE); if (test_event_condition(all, num_events, event_waiters)) { - if (copy_signaled_event_data(num_events, - event_waiters, events)) - *wait_result = KFD_WAIT_COMPLETE; - else - *wait_result = KFD_WAIT_ERROR; + *wait_result = KFD_IOC_WAIT_RESULT_COMPLETE; break; } if (timeout <= 0) { - *wait_result = KFD_WAIT_TIMEOUT; + *wait_result = KFD_IOC_WAIT_RESULT_TIMEOUT; break; } @@ -835,19 +823,20 @@ int kfd_wait_on_events(struct kfd_process *p, } __set_current_state(TASK_RUNNING); + /* copy_signaled_event_data may sleep. So this has to happen + * after the task state is set back to RUNNING. + */ + if (!ret && *wait_result == KFD_IOC_WAIT_RESULT_COMPLETE) + ret = copy_signaled_event_data(num_events, + event_waiters, events); + mutex_lock(&p->event_mutex); +out_unlock: free_waiters(num_events, event_waiters); mutex_unlock(&p->event_mutex); - - return ret; - -fail: - if (event_waiters) - free_waiters(num_events, event_waiters); - - mutex_unlock(&p->event_mutex); - - *wait_result = KFD_WAIT_ERROR; +out: + if (ret) + *wait_result = KFD_IOC_WAIT_RESULT_FAIL; return ret; } diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h index 1a483a7..d3cf53a 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h +++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h @@ -726,19 +726,13 @@ uint64_t kfd_get_number_elems(struct kfd_dev *kfd); extern const struct kfd_event_interrupt_class event_interrupt_class_cik; extern const struct kfd_device_global_init_class device_global_init_class_cik; -enum kfd_event_wait_result { - KFD_WAIT_COMPLETE, - KFD_WAIT_TIMEOUT, - KFD_WAIT_ERROR -}; - void kfd_event_init_process(struct kfd_process *p); void kfd_event_free_process(struct kfd_process *p); int kfd_event_mmap(struct kfd_process *process, struct vm_area_struct *vma); int kfd_wait_on_events(struct kfd_process *p, uint32_t num_events, void __user *data, bool all, uint32_t user_timeout_ms, - enum kfd_event_wait_result *wait_result); + uint32_t *wait_result); void kfd_signal_event_interrupt(unsigned int pasid, uint32_t partial_id, uint32_t valid_id_bits); void kfd_signal_iommu_event(struct kfd_dev *dev, -- 2.7.4