Return-path: Received: from mail-wi0-f175.google.com ([209.85.212.175]:54883 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752481AbaEGTyB (ORCPT ); Wed, 7 May 2014 15:54:01 -0400 Received: by mail-wi0-f175.google.com with SMTP id f8so5926048wiw.14 for ; Wed, 07 May 2014 12:53:59 -0700 (PDT) From: Emmanuel Grumbach To: linux-wireless@vger.kernel.org Cc: Johannes Berg , Emmanuel Grumbach Subject: [PATCH 17/23] iwlwifi: pcie: get rid of q->n_bd Date: Wed, 7 May 2014 22:52:54 +0300 Message-Id: <1399492380-12050-17-git-send-email-egrumbach@gmail.com> (sfid-20140507_215425_670989_4F924C88) In-Reply-To: <536A8EE3.2050906@gmail.com> References: <536A8EE3.2050906@gmail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Johannes Berg This variable always tracks a constant value (256) so there's no need to have it. Removing it simplifies code generation, reducing the .text size (by about 240 bytes on x86-64.) Signed-off-by: Johannes Berg Signed-off-by: Emmanuel Grumbach --- drivers/net/wireless/iwlwifi/pcie/internal.h | 17 +++---- drivers/net/wireless/iwlwifi/pcie/rx.c | 2 +- drivers/net/wireless/iwlwifi/pcie/trans.c | 4 +- drivers/net/wireless/iwlwifi/pcie/tx.c | 75 +++++++++++++--------------- 4 files changed, 45 insertions(+), 53 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/pcie/internal.h b/drivers/net/wireless/iwlwifi/pcie/internal.h index 1b95d85..ab21aee 100644 --- a/drivers/net/wireless/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/iwlwifi/pcie/internal.h @@ -117,21 +117,19 @@ struct iwl_dma_ptr { /** * iwl_queue_inc_wrap - increment queue index, wrap back to beginning * @index -- current index - * @n_bd -- total number of entries in queue (must be power of 2) */ -static inline int iwl_queue_inc_wrap(int index, int n_bd) +static inline int iwl_queue_inc_wrap(int index) { - return ++index & (n_bd - 1); + return ++index & (TFD_QUEUE_SIZE_MAX - 1); } /** * iwl_queue_dec_wrap - decrement queue index, wrap back to end * @index -- current index - * @n_bd -- total number of entries in queue (must be power of 2) */ -static inline int iwl_queue_dec_wrap(int index, int n_bd) +static inline int iwl_queue_dec_wrap(int index) { - return --index & (n_bd - 1); + return --index & (TFD_QUEUE_SIZE_MAX - 1); } struct iwl_cmd_meta { @@ -145,13 +143,13 @@ struct iwl_cmd_meta { * * Contains common data for Rx and Tx queues. * - * Note the difference between n_bd and n_window: the hardware - * always assumes 256 descriptors, so n_bd is always 256 (unless + * Note the difference between TFD_QUEUE_SIZE_MAX and n_window: the hardware + * always assumes 256 descriptors, so TFD_QUEUE_SIZE_MAX is always 256 (unless * there might be HW changes in the future). For the normal TX * queues, n_window, which is the size of the software queue data * is also 256; however, for the command queue, n_window is only * 32 since we don't need so many commands pending. Since the HW - * still uses 256 BDs for DMA though, n_bd stays 256. As a result, + * still uses 256 BDs for DMA though, TFD_QUEUE_SIZE_MAX stays 256. As a result, * the software buffers (in the variables @meta, @txb in struct * iwl_txq) only have 32 entries, while the HW buffers (@tfds in * the same struct) have 256. @@ -162,7 +160,6 @@ struct iwl_cmd_meta { * data is a window overlayed over the HW queue. */ struct iwl_queue { - int n_bd; /* number of BDs in this queue */ int write_ptr; /* 1-st empty entry (index) host_w*/ int read_ptr; /* last used entry (index) host_r*/ /* use for monitoring and recovering the stuck queue */ diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c index 4a26a08..a2698e5 100644 --- a/drivers/net/wireless/iwlwifi/pcie/rx.c +++ b/drivers/net/wireless/iwlwifi/pcie/rx.c @@ -850,7 +850,7 @@ static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans) trans_pcie->ict_index, read); trans_pcie->ict_tbl[trans_pcie->ict_index] = 0; trans_pcie->ict_index = - iwl_queue_inc_wrap(trans_pcie->ict_index, ICT_COUNT); + ((trans_pcie->ict_index + 1) & (ICT_COUNT - 1)); read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]); trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, diff --git a/drivers/net/wireless/iwlwifi/pcie/trans.c b/drivers/net/wireless/iwlwifi/pcie/trans.c index f98ef1e..a6f8622 100644 --- a/drivers/net/wireless/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/iwlwifi/pcie/trans.c @@ -1337,8 +1337,8 @@ static int iwl_trans_pcie_wait_txq_empty(struct iwl_trans *trans, u32 txq_bm) IWL_ERR(trans, "Q %d is %sactive and mapped to fifo %d ra_tid 0x%04x [%d,%d]\n", cnt, active ? "" : "in", fifo, tbl_dw, - iwl_read_prph(trans, - SCD_QUEUE_RDPTR(cnt)) & (txq->q.n_bd - 1), + iwl_read_prph(trans, SCD_QUEUE_RDPTR(cnt)) & + (TFD_QUEUE_SIZE_MAX - 1), iwl_read_prph(trans, SCD_QUEUE_WRPTR(cnt))); } diff --git a/drivers/net/wireless/iwlwifi/pcie/tx.c b/drivers/net/wireless/iwlwifi/pcie/tx.c index 16ebc4a..93709fe 100644 --- a/drivers/net/wireless/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/iwlwifi/pcie/tx.c @@ -70,20 +70,20 @@ static int iwl_queue_space(const struct iwl_queue *q) /* * To avoid ambiguity between empty and completely full queues, there - * should always be less than q->n_bd elements in the queue. - * If q->n_window is smaller than q->n_bd, there is no need to reserve - * any queue entries for this purpose. + * should always be less than TFD_QUEUE_SIZE_MAX elements in the queue. + * If q->n_window is smaller than TFD_QUEUE_SIZE_MAX, there is no need + * to reserve any queue entries for this purpose. */ - if (q->n_window < q->n_bd) + if (q->n_window < TFD_QUEUE_SIZE_MAX) max = q->n_window; else - max = q->n_bd - 1; + max = TFD_QUEUE_SIZE_MAX - 1; /* - * q->n_bd is a power of 2, so the following is equivalent to modulo by - * q->n_bd and is well defined for negative dividends. + * TFD_QUEUE_SIZE_MAX is a power of 2, so the following is equivalent to + * modulo by TFD_QUEUE_SIZE_MAX and is well defined. */ - used = (q->write_ptr - q->read_ptr) & (q->n_bd - 1); + used = (q->write_ptr - q->read_ptr) & (TFD_QUEUE_SIZE_MAX - 1); if (WARN_ON(used > max)) return 0; @@ -94,17 +94,11 @@ static int iwl_queue_space(const struct iwl_queue *q) /* * iwl_queue_init - Initialize queue's high/low-water and read/write indexes */ -static int iwl_queue_init(struct iwl_queue *q, int count, int slots_num, u32 id) +static int iwl_queue_init(struct iwl_queue *q, int slots_num, u32 id) { - q->n_bd = count; q->n_window = slots_num; q->id = id; - /* count must be power-of-two size, otherwise iwl_queue_inc_wrap - * and iwl_queue_dec_wrap are broken. */ - if (WARN_ON(!is_power_of_2(count))) - return -EINVAL; - /* slots_num must be power-of-two size, otherwise * get_cmd_index is broken. */ if (WARN_ON(!is_power_of_2(slots_num))) @@ -197,13 +191,13 @@ static void iwl_pcie_txq_stuck_timer(unsigned long data) IWL_ERR(trans, "Q %d is %sactive and mapped to fifo %d ra_tid 0x%04x [%d,%d]\n", i, active ? "" : "in", fifo, tbl_dw, - iwl_read_prph(trans, - SCD_QUEUE_RDPTR(i)) & (txq->q.n_bd - 1), + iwl_read_prph(trans, SCD_QUEUE_RDPTR(i)) & + (TFD_QUEUE_SIZE_MAX - 1), iwl_read_prph(trans, SCD_QUEUE_WRPTR(i))); } for (i = q->read_ptr; i != q->write_ptr; - i = iwl_queue_inc_wrap(i, q->n_bd)) + i = iwl_queue_inc_wrap(i)) IWL_ERR(trans, "scratch %d = 0x%08x\n", i, le32_to_cpu(txq->scratchbufs[i].scratch)); @@ -425,13 +419,17 @@ static void iwl_pcie_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq) { struct iwl_tfd *tfd_tmp = txq->tfds; - /* rd_ptr is bounded by n_bd and idx is bounded by n_window */ + /* rd_ptr is bounded by TFD_QUEUE_SIZE_MAX and + * idx is bounded by n_window + */ int rd_ptr = txq->q.read_ptr; int idx = get_cmd_index(&txq->q, rd_ptr); lockdep_assert_held(&txq->lock); - /* We have only q->n_window txq->entries, but we use q->n_bd tfds */ + /* We have only q->n_window txq->entries, but we use + * TFD_QUEUE_SIZE_MAX tfds + */ iwl_pcie_tfd_unmap(trans, &txq->entries[idx].meta, &tfd_tmp[rd_ptr]); /* free SKB */ @@ -565,8 +563,7 @@ static int iwl_pcie_txq_init(struct iwl_trans *trans, struct iwl_txq *txq, BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1)); /* Initialize queue's high/low-water marks, and head/tail indexes */ - ret = iwl_queue_init(&txq->q, TFD_QUEUE_SIZE_MAX, slots_num, - txq_id); + ret = iwl_queue_init(&txq->q, slots_num, txq_id); if (ret) return ret; @@ -591,15 +588,12 @@ static void iwl_pcie_txq_unmap(struct iwl_trans *trans, int txq_id) struct iwl_txq *txq = &trans_pcie->txq[txq_id]; struct iwl_queue *q = &txq->q; - if (!q->n_bd) - return; - spin_lock_bh(&txq->lock); while (q->write_ptr != q->read_ptr) { IWL_DEBUG_TX_REPLY(trans, "Q %d Free %d\n", txq_id, q->read_ptr); iwl_pcie_txq_free_tfd(trans, txq); - q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd); + q->read_ptr = iwl_queue_inc_wrap(q->read_ptr); } txq->active = false; spin_unlock_bh(&txq->lock); @@ -636,10 +630,12 @@ static void iwl_pcie_txq_free(struct iwl_trans *trans, int txq_id) } /* De-alloc circular buffer of TFDs */ - if (txq->q.n_bd) { - dma_free_coherent(dev, sizeof(struct iwl_tfd) * - txq->q.n_bd, txq->tfds, txq->q.dma_addr); + if (txq->tfds) { + dma_free_coherent(dev, + sizeof(struct iwl_tfd) * TFD_QUEUE_SIZE_MAX, + txq->tfds, txq->q.dma_addr); txq->q.dma_addr = 0; + txq->tfds = NULL; dma_free_coherent(dev, sizeof(*txq->scratchbufs) * txq->q.n_window, @@ -948,8 +944,7 @@ void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn, { struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); struct iwl_txq *txq = &trans_pcie->txq[txq_id]; - /* n_bd is usually 256 => n_bd - 1 = 0xff */ - int tfd_num = ssn & (txq->q.n_bd - 1); + int tfd_num = ssn & (TFD_QUEUE_SIZE_MAX - 1); struct iwl_queue *q = &txq->q; int last_to_free; @@ -973,12 +968,12 @@ void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn, /*Since we free until index _not_ inclusive, the one before index is * the last we will free. This one must be used */ - last_to_free = iwl_queue_dec_wrap(tfd_num, q->n_bd); + last_to_free = iwl_queue_dec_wrap(tfd_num); if (!iwl_queue_used(q, last_to_free)) { IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), last_to_free %d is out of range [0-%d] %d %d.\n", - __func__, txq_id, last_to_free, q->n_bd, + __func__, txq_id, last_to_free, TFD_QUEUE_SIZE_MAX, q->write_ptr, q->read_ptr); goto out; } @@ -988,7 +983,7 @@ void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn, for (; q->read_ptr != tfd_num; - q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) { + q->read_ptr = iwl_queue_inc_wrap(q->read_ptr)) { if (WARN_ON_ONCE(txq->entries[txq->q.read_ptr].skb == NULL)) continue; @@ -1027,16 +1022,16 @@ static void iwl_pcie_cmdq_reclaim(struct iwl_trans *trans, int txq_id, int idx) lockdep_assert_held(&txq->lock); - if ((idx >= q->n_bd) || (!iwl_queue_used(q, idx))) { + if ((idx >= TFD_QUEUE_SIZE_MAX) || (!iwl_queue_used(q, idx))) { IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), index %d is out of range [0-%d] %d %d.\n", - __func__, txq_id, idx, q->n_bd, + __func__, txq_id, idx, TFD_QUEUE_SIZE_MAX, q->write_ptr, q->read_ptr); return; } - for (idx = iwl_queue_inc_wrap(idx, q->n_bd); q->read_ptr != idx; - q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) { + for (idx = iwl_queue_inc_wrap(idx); q->read_ptr != idx; + q->read_ptr = iwl_queue_inc_wrap(q->read_ptr)) { if (nfreed++ > 0) { IWL_ERR(trans, "HCMD skipped: index (%d) %d %d\n", @@ -1445,7 +1440,7 @@ static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans, } /* Increment and update queue's write index */ - q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd); + q->write_ptr = iwl_queue_inc_wrap(q->write_ptr); iwl_pcie_txq_inc_wr_ptr(trans, txq); spin_unlock_irqrestore(&trans_pcie->reg_lock, flags); @@ -1788,7 +1783,7 @@ int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb, mod_timer(&txq->stuck_timer, jiffies + trans_pcie->wd_timeout); /* Tell device the write index *just past* this latest filled TFD */ - q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd); + q->write_ptr = iwl_queue_inc_wrap(q->write_ptr); if (!wait_write_ptr) iwl_pcie_txq_inc_wr_ptr(trans, txq); -- 1.8.3.2