From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Christie Date: Wed, 18 Oct 2017 07:14:01 +0000 Subject: [PATCH 06/17] tcmu: split unmap_thread_fn Message-Id: <1508310852-15366-7-git-send-email-mchristi@redhat.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: target-devel@vger.kernel.org Separate unmap_thread_fn to make it easier to read. Signed-off-by: Mike Christie --- drivers/target/target_core_user.c | 149 +++++++++++++++++++++----------------- 1 file changed, 81 insertions(+), 68 deletions(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index a222d15..5ce0034 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -2047,6 +2047,84 @@ static struct target_backend_ops tcmu_ops = { .tb_dev_attrib_attrs = NULL, }; +static uint32_t find_free_blocks(void) +{ + struct tcmu_dev *udev; + loff_t off; + uint32_t start, end, block, free_blocks = 0; + + mutex_lock(&root_udev_mutex); + list_for_each_entry(udev, &root_udev, node) { + mutex_lock(&udev->cmdr_lock); + + /* Try to complete the finished commands first */ + tcmu_handle_completions(udev); + + /* Skip the udevs waiting the global pool or in idle */ + if (is_in_waiter_list(udev) || !udev->dbi_thresh) { + mutex_unlock(&udev->cmdr_lock); + continue; + } + + end = udev->dbi_max + 1; + block = find_last_bit(udev->data_bitmap, end); + if (block = udev->dbi_max) { + /* + * The last bit is dbi_max, so there is + * no need to shrink any blocks. + */ + mutex_unlock(&udev->cmdr_lock); + continue; + } else if (block = end) { + /* The current udev will goto idle state */ + udev->dbi_thresh = start = 0; + udev->dbi_max = 0; + } else { + udev->dbi_thresh = start = block + 1; + udev->dbi_max = block; + } + + /* Here will truncate the data area from off */ + off = udev->data_off + start * DATA_BLOCK_SIZE; + unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); + + /* Release the block pages */ + tcmu_blocks_release(&udev->data_blocks, start, end); + mutex_unlock(&udev->cmdr_lock); + + free_blocks += end - start; + } + mutex_unlock(&root_udev_mutex); + return free_blocks; +} + +static void run_cmdr_queues(uint32_t *free_blocks) +{ + struct tcmu_dev *udev, *tmp; + + /* + * Try to wake up the udevs who are waiting + * for the global data pool blocks. + */ + mutex_lock(&root_udev_waiter_mutex); + list_for_each_entry_safe(udev, tmp, &root_udev_waiter, waiter) { + mutex_lock(&udev->cmdr_lock); + if (udev->waiting_blocks < *free_blocks) { + mutex_unlock(&udev->cmdr_lock); + break; + } + + *free_blocks -= udev->waiting_blocks; + udev->waiting_blocks = 0; + mutex_unlock(&udev->cmdr_lock); + + list_del(&udev->waiter); + + wake_up(&udev->wait_cmdr); + } + mutex_unlock(&root_udev_waiter_mutex); +} + static void check_timedout_devices(void) { struct tcmu_dev *udev, *tmp_dev; @@ -2070,10 +2148,7 @@ static void check_timedout_devices(void) static int unmap_thread_fn(void *data) { - struct tcmu_dev *udev, *tmp; - loff_t off; - uint32_t start, end, block; - static uint32_t free_blocks; + uint32_t free_blocks = 0; bool has_timed_out_devs; while (!kthread_should_stop()) { @@ -2097,70 +2172,8 @@ static int unmap_thread_fn(void *data) check_timedout_devices(); - mutex_lock(&root_udev_mutex); - list_for_each_entry(udev, &root_udev, node) { - mutex_lock(&udev->cmdr_lock); - - /* Try to complete the finished commands first */ - tcmu_handle_completions(udev); - - /* Skip the udevs waiting the global pool or in idle */ - if (is_in_waiter_list(udev) || !udev->dbi_thresh) { - mutex_unlock(&udev->cmdr_lock); - continue; - } - - end = udev->dbi_max + 1; - block = find_last_bit(udev->data_bitmap, end); - if (block = udev->dbi_max) { - /* - * The last bit is dbi_max, so there is - * no need to shrink any blocks. - */ - mutex_unlock(&udev->cmdr_lock); - continue; - } else if (block = end) { - /* The current udev will goto idle state */ - udev->dbi_thresh = start = 0; - udev->dbi_max = 0; - } else { - udev->dbi_thresh = start = block + 1; - udev->dbi_max = block; - } - - /* Here will truncate the data area from off */ - off = udev->data_off + start * DATA_BLOCK_SIZE; - unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); - - /* Release the block pages */ - tcmu_blocks_release(&udev->data_blocks, start, end); - mutex_unlock(&udev->cmdr_lock); - - free_blocks += end - start; - } - mutex_unlock(&root_udev_mutex); - - /* - * Try to wake up the udevs who are waiting - * for the global data pool blocks. - */ - mutex_lock(&root_udev_waiter_mutex); - list_for_each_entry_safe(udev, tmp, &root_udev_waiter, waiter) { - mutex_lock(&udev->cmdr_lock); - if (udev->waiting_blocks < free_blocks) { - mutex_unlock(&udev->cmdr_lock); - break; - } - - free_blocks -= udev->waiting_blocks; - udev->waiting_blocks = 0; - mutex_unlock(&udev->cmdr_lock); - - list_del(&udev->waiter); - - wake_up(&udev->wait_cmdr); - } - mutex_unlock(&root_udev_waiter_mutex); + free_blocks += find_free_blocks(); + run_cmdr_queues(&free_blocks); } return 0; -- 2.7.2