Counting semaphores are going away in the future, so replace the semaphore mthca_cmd::event_sem with a conditional wait_event.
Signed-off-by: Binoy Jayan <binoy.ja...@linaro.org> --- drivers/infiniband/hw/mthca/mthca_cmd.c | 47 ++++++++++++++++++++++----------- drivers/infiniband/hw/mthca/mthca_dev.h | 3 ++- 2 files changed, 34 insertions(+), 16 deletions(-) diff --git a/drivers/infiniband/hw/mthca/mthca_cmd.c b/drivers/infiniband/hw/mthca/mthca_cmd.c index 49c6e19..d6a048a 100644 --- a/drivers/infiniband/hw/mthca/mthca_cmd.c +++ b/drivers/infiniband/hw/mthca/mthca_cmd.c @@ -405,6 +405,34 @@ void mthca_cmd_event(struct mthca_dev *dev, complete(&context->done); } +static inline struct mthca_cmd_context * +mthca_try_get_context(struct mthca_cmd *cmd) +{ + struct mthca_cmd_context *context = NULL; + + spin_lock(&cmd->context_lock); + + if (cmd->free_head < 0) + goto out; + + context = &cmd->context[cmd->free_head]; + context->token += cmd->token_mask + 1; + cmd->free_head = context->next; +out: + spin_unlock(&cmd->context_lock); + return context; +} + +/* wait for and acquire a free context */ +static inline struct mthca_cmd_context * +mthca_get_free_context(struct mthca_cmd *cmd) +{ + struct mthca_cmd_context *context; + + wait_event(cmd->wq, (context = mthca_try_get_context(cmd))); + return context; +} + static int mthca_cmd_wait(struct mthca_dev *dev, u64 in_param, u64 *out_param, @@ -417,15 +445,7 @@ static int mthca_cmd_wait(struct mthca_dev *dev, int err = 0; struct mthca_cmd_context *context; - down(&dev->cmd.event_sem); - - spin_lock(&dev->cmd.context_lock); - BUG_ON(dev->cmd.free_head < 0); - context = &dev->cmd.context[dev->cmd.free_head]; - context->token += dev->cmd.token_mask + 1; - dev->cmd.free_head = context->next; - spin_unlock(&dev->cmd.context_lock); - + context = mthca_get_free_context(&dev->cmd); init_completion(&context->done); err = mthca_cmd_post(dev, in_param, @@ -458,8 +478,8 @@ static int mthca_cmd_wait(struct mthca_dev *dev, context->next = dev->cmd.free_head; dev->cmd.free_head = context - dev->cmd.context; spin_unlock(&dev->cmd.context_lock); + wake_up(&dev->cmd.wq); - up(&dev->cmd.event_sem); return err; } @@ -571,7 +591,7 @@ int mthca_cmd_use_events(struct mthca_dev *dev) dev->cmd.context[dev->cmd.max_cmds - 1].next = -1; dev->cmd.free_head = 0; - sema_init(&dev->cmd.event_sem, dev->cmd.max_cmds); + init_waitqueue_head(&dev->cmd.wq); spin_lock_init(&dev->cmd.context_lock); for (dev->cmd.token_mask = 1; @@ -590,12 +610,9 @@ int mthca_cmd_use_events(struct mthca_dev *dev) */ void mthca_cmd_use_polling(struct mthca_dev *dev) { - int i; - dev->cmd.flags &= ~MTHCA_CMD_USE_EVENTS; - for (i = 0; i < dev->cmd.max_cmds; ++i) - down(&dev->cmd.event_sem); + dev->cmd.free_head = -1; kfree(dev->cmd.context); } diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h index 87ab964..2fc86db 100644 --- a/drivers/infiniband/hw/mthca/mthca_dev.h +++ b/drivers/infiniband/hw/mthca/mthca_dev.h @@ -46,6 +46,7 @@ #include <linux/list.h> #include <linux/semaphore.h> +#include <rdma/ib_sa.h> #include "mthca_provider.h" #include "mthca_doorbell.h" @@ -121,7 +122,7 @@ struct mthca_cmd { struct pci_pool *pool; struct mutex hcr_mutex; struct mutex poll_mutex; - struct semaphore event_sem; + wait_queue_head_t wq; int max_cmds; spinlock_t context_lock; int free_head; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project