Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756639AbZIDGon (ORCPT ); Fri, 4 Sep 2009 02:44:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750809AbZIDGol (ORCPT ); Fri, 4 Sep 2009 02:44:41 -0400 Received: from mga14.intel.com ([143.182.124.37]:13128 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755706AbZIDGoi (ORCPT ); Fri, 4 Sep 2009 02:44:38 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.44,271,1249282800"; d="scan'208";a="184024766" Subject: [PATCH 01/18] dmaengine: add fence support To: linux-kernel@vger.kernel.org From: Dan Williams Cc: linux-raid@vger.kernel.org, maciej.sosnowski@intel.com Date: Thu, 03 Sep 2009 23:44:40 -0700 Message-ID: <20090904064440.7141.72561.stgit@dwillia2-linux.ch.intel.com> In-Reply-To: <20090904064308.7141.30576.stgit@dwillia2-linux.ch.intel.com> References: <20090904064308.7141.30576.stgit@dwillia2-linux.ch.intel.com> User-Agent: StGit/0.14.3.289.g7daff MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 16933 Lines: 423 Some engines optimize operation by reading ahead in the descriptor chain such that descriptor2 may start execution before descriptor1 completes. If descriptor2 depends on the result from descriptor1 then a fence is required (on descriptor2) to disable this optimization. The async_tx api could implicitly identify dependencies via the 'depend_tx' parameter, but that would constrain cases where the dependency chain only specifies a completion order rather than a data dependency. So, provide an ASYNC_TX_FENCE to explicitly identify data dependencies. Signed-off-by: Dan Williams --- crypto/async_tx/async_memcpy.c | 7 ++++- crypto/async_tx/async_memset.c | 7 ++++- crypto/async_tx/async_pq.c | 5 ++++ crypto/async_tx/async_raid6_recov.c | 47 ++++++++++++++++++++--------------- crypto/async_tx/async_xor.c | 11 ++++++-- drivers/md/raid5.c | 37 +++++++++++++++++----------- include/linux/async_tx.h | 3 ++ include/linux/dmaengine.h | 3 ++ 8 files changed, 79 insertions(+), 41 deletions(-) diff --git a/crypto/async_tx/async_memcpy.c b/crypto/async_tx/async_memcpy.c index 98e15bd..b38cbb3 100644 --- a/crypto/async_tx/async_memcpy.c +++ b/crypto/async_tx/async_memcpy.c @@ -52,9 +52,12 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset, if (device) { dma_addr_t dma_dest, dma_src; - unsigned long dma_prep_flags; + unsigned long dma_prep_flags = 0; - dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; dma_dest = dma_map_page(device->dev, dest, dest_offset, len, DMA_FROM_DEVICE); diff --git a/crypto/async_tx/async_memset.c b/crypto/async_tx/async_memset.c index b896a6e..a374784 100644 --- a/crypto/async_tx/async_memset.c +++ b/crypto/async_tx/async_memset.c @@ -49,9 +49,12 @@ async_memset(struct page *dest, int val, unsigned int offset, size_t len, if (device) { dma_addr_t dma_dest; - unsigned long dma_prep_flags; + unsigned long dma_prep_flags = 0; - dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; dma_dest = dma_map_page(device->dev, dest, offset, len, DMA_FROM_DEVICE); diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c index 108b21e..a25e290 100644 --- a/crypto/async_tx/async_pq.c +++ b/crypto/async_tx/async_pq.c @@ -101,6 +101,7 @@ do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks, */ if (src_cnt > pq_src_cnt) { submit->flags &= ~ASYNC_TX_ACK; + submit->flags |= ASYNC_TX_FENCE; dma_flags |= DMA_COMPL_SKIP_DEST_UNMAP; submit->cb_fn = NULL; submit->cb_param = NULL; @@ -111,6 +112,8 @@ do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks, if (cb_fn_orig) dma_flags |= DMA_PREP_INTERRUPT; } + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; /* Since we have clobbered the src_list we are committed * to doing this asynchronously. Drivers force forward @@ -282,6 +285,8 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks, dma_flags |= DMA_PREP_PQ_DISABLE_P; if (!Q(blocks, disks)) dma_flags |= DMA_PREP_PQ_DISABLE_Q; + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; for (i = 0; i < disks; i++) if (likely(blocks[i])) { BUG_ON(is_raid6_zero_block(blocks[i])); diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c index 0c14d48..822a42d 100644 --- a/crypto/async_tx/async_raid6_recov.c +++ b/crypto/async_tx/async_raid6_recov.c @@ -44,6 +44,8 @@ async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef, struct dma_async_tx_descriptor *tx; enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); dma_src[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE); dma_src[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE); @@ -89,6 +91,8 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len, struct dma_async_tx_descriptor *tx; enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P; + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL); dma_src[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE); tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 1, &coef, @@ -138,7 +142,7 @@ __2data_recov_4(size_t bytes, int faila, int failb, struct page **blocks, srcs[1] = q; coef[0] = raid6_gfexi[failb-faila]; coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_sum_product(b, srcs, coef, bytes, submit); /* Dy = P+Pxy+Dx */ @@ -188,23 +192,23 @@ __2data_recov_5(size_t bytes, int faila, int failb, struct page **blocks, dp = blocks[faila]; dq = blocks[failb]; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_memcpy(dp, g, 0, 0, bytes, submit); - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); /* compute P + Pxy */ srcs[0] = dp; srcs[1] = p; - init_async_submit(submit, ASYNC_TX_XOR_DROP_DST, tx, NULL, NULL, - scribble); + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); tx = async_xor(dp, srcs, 0, 2, bytes, submit); /* compute Q + Qxy */ srcs[0] = dq; srcs[1] = q; - init_async_submit(submit, ASYNC_TX_XOR_DROP_DST, tx, NULL, NULL, - scribble); + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); tx = async_xor(dq, srcs, 0, 2, bytes, submit); /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ @@ -212,7 +216,7 @@ __2data_recov_5(size_t bytes, int faila, int failb, struct page **blocks, srcs[1] = dq; coef[0] = raid6_gfexi[failb-faila]; coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_sum_product(dq, srcs, coef, bytes, submit); /* Dy = P+Pxy+Dx */ @@ -252,7 +256,7 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb, blocks[failb] = (void *)raid6_empty_zero_page; blocks[disks-1] = dq; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); /* Restore pointer table */ @@ -264,15 +268,15 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb, /* compute P + Pxy */ srcs[0] = dp; srcs[1] = p; - init_async_submit(submit, ASYNC_TX_XOR_DROP_DST, tx, NULL, NULL, - scribble); + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); tx = async_xor(dp, srcs, 0, 2, bytes, submit); /* compute Q + Qxy */ srcs[0] = dq; srcs[1] = q; - init_async_submit(submit, ASYNC_TX_XOR_DROP_DST, tx, NULL, NULL, - scribble); + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); tx = async_xor(dq, srcs, 0, 2, bytes, submit); /* Dx = A*(P+Pxy) + B*(Q+Qxy) */ @@ -280,7 +284,7 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb, srcs[1] = dq; coef[0] = raid6_gfexi[failb-faila]; coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_sum_product(dq, srcs, coef, bytes, submit); /* Dy = P+Pxy+Dx */ @@ -407,13 +411,16 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila, int good = faila == 0 ? 1 : 0; struct page *g = blocks[good]; - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); tx = async_memcpy(p, g, 0, 0, bytes, submit); - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit); } else { - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, + scribble); tx = async_gen_syndrome(blocks, 0, disks, bytes, submit); } @@ -426,11 +433,11 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila, srcs[0] = dq; srcs[1] = q; - init_async_submit(submit, ASYNC_TX_XOR_DROP_DST, tx, NULL, NULL, - scribble); + init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, + NULL, NULL, scribble); tx = async_xor(dq, srcs, 0, 2, bytes, submit); - init_async_submit(submit, 0, tx, NULL, NULL, scribble); + init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble); tx = async_mult(dq, dq, coef, bytes, submit); srcs[0] = p; diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c index 56b5f98..db27987 100644 --- a/crypto/async_tx/async_xor.c +++ b/crypto/async_tx/async_xor.c @@ -69,6 +69,7 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list, */ if (src_cnt > xor_src_cnt) { submit->flags &= ~ASYNC_TX_ACK; + submit->flags |= ASYNC_TX_FENCE; dma_flags = DMA_COMPL_SKIP_DEST_UNMAP; submit->cb_fn = NULL; submit->cb_param = NULL; @@ -78,7 +79,8 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list, } if (submit->cb_fn) dma_flags |= DMA_PREP_INTERRUPT; - + if (submit->flags & ASYNC_TX_FENCE) + dma_flags |= DMA_PREP_FENCE; /* Since we have clobbered the src_list we are committed * to doing this asynchronously. Drivers force forward progress * in case they can not provide a descriptor @@ -264,12 +266,15 @@ async_xor_val(struct page *dest, struct page **src_list, unsigned int offset, dma_src = (dma_addr_t *) src_list; if (dma_src && device && src_cnt <= device->max_xor) { - unsigned long dma_prep_flags; + unsigned long dma_prep_flags = 0; int i; pr_debug("%s: (async) len: %zu\n", __func__, len); - dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0; + if (submit->cb_fn) + dma_prep_flags |= DMA_PREP_INTERRUPT; + if (submit->flags & ASYNC_TX_FENCE) + dma_prep_flags |= DMA_PREP_FENCE; for (i = 0; i < src_cnt; i++) dma_src[i] = dma_map_page(device->dev, src_list[i], offset, len, DMA_TO_DEVICE); diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 0a5cf21..54ef8d7 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -502,13 +502,17 @@ async_copy_data(int frombio, struct bio *bio, struct page *page, int i; int page_offset; struct async_submit_ctl submit; + enum async_tx_flags flags = 0; if (bio->bi_sector >= sector) page_offset = (signed)(bio->bi_sector - sector) * 512; else page_offset = (signed)(sector - bio->bi_sector) * -512; - init_async_submit(&submit, 0, tx, NULL, NULL, NULL); + if (frombio) + flags |= ASYNC_TX_FENCE; + init_async_submit(&submit, flags, tx, NULL, NULL, NULL); + bio_for_each_segment(bvl, bio, i) { int len = bio_iovec_idx(bio, i)->bv_len; int clen; @@ -685,7 +689,7 @@ ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu) atomic_inc(&sh->count); - init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, + init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL, ops_complete_compute, sh, to_addr_conv(sh, percpu)); if (unlikely(count == 1)) tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit); @@ -763,7 +767,8 @@ ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu) count = set_syndrome_sources(blocks, sh); blocks[count] = NULL; /* regenerating p is not necessary */ BUG_ON(blocks[count+1] != dest); /* q should already be set */ - init_async_submit(&submit, 0, NULL, ops_complete_compute, sh, + init_async_submit(&submit, ASYNC_TX_FENCE, NULL, + ops_complete_compute, sh, to_addr_conv(sh, percpu)); tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit); } else { @@ -775,8 +780,8 @@ ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu) blocks[count++] = sh->dev[i].page; } - init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, - ops_complete_compute, sh, + init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, + NULL, ops_complete_compute, sh, to_addr_conv(sh, percpu)); tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit); } @@ -837,8 +842,9 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu) /* Q disk is one of the missing disks */ if (faila == syndrome_disks) { /* Missing P+Q, just recompute */ - init_async_submit(&submit, 0, NULL, ops_complete_compute, - sh, to_addr_conv(sh, percpu)); + init_async_submit(&submit, ASYNC_TX_FENCE, NULL, + ops_complete_compute, sh, + to_addr_conv(sh, percpu)); return async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit); } else { @@ -859,21 +865,24 @@ ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu) blocks[count++] = sh->dev[i].page; } dest = sh->dev[data_target].page; - init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, - NULL, NULL, to_addr_conv(sh, percpu)); + init_async_submit(&submit, + ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, + NULL, NULL, NULL, + to_addr_conv(sh, percpu)); tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit); count = set_syndrome_sources(blocks, sh); - init_async_submit(&submit, 0, tx, ops_complete_compute, - sh, to_addr_conv(sh, percpu)); + init_async_submit(&submit, ASYNC_TX_FENCE, tx, + ops_complete_compute, sh, + to_addr_conv(sh, percpu)); return async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit); } } - init_async_submit(&submit, 0, NULL, ops_complete_compute, sh, - to_addr_conv(sh, percpu)); + init_async_submit(&submit, ASYNC_TX_FENCE, NULL, ops_complete_compute, + sh, to_addr_conv(sh, percpu)); if (failb == syndrome_disks) { /* We're missing D+P. */ return async_raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, @@ -916,7 +925,7 @@ ops_run_prexor(struct stripe_head *sh, struct raid5_percpu *percpu, xor_srcs[count++] = dev->page; } - init_async_submit(&submit, ASYNC_TX_XOR_DROP_DST, tx, + init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx, ops_complete_prexor, sh, to_addr_conv(sh, percpu)); tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit); diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h index 866e61c..a1c486a 100644 --- a/include/linux/async_tx.h +++ b/include/linux/async_tx.h @@ -58,11 +58,14 @@ struct dma_chan_ref { * array. * @ASYNC_TX_ACK: immediately ack the descriptor, precludes setting up a * dependency chain + * @ASYNC_TX_FENCE: specify that the next operation in the dependency + * chain uses this operation's result as an input */ enum async_tx_flags { ASYNC_TX_XOR_ZERO_DST = (1 << 0), ASYNC_TX_XOR_DROP_DST = (1 << 1), ASYNC_TX_ACK = (1 << 2), + ASYNC_TX_FENCE = (1 << 3), }; /** diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 2fe9bf1..176f827 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -87,6 +87,8 @@ enum dma_transaction_type { * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as * sources that were the result of a previous operation, in the case of a PQ * operation it continues the calculation with new sources + * @DMA_PREP_FENCE - tell the driver that subsequent operations depend + * on the result of this operation */ enum dma_ctrl_flags { DMA_PREP_INTERRUPT = (1 << 0), @@ -98,6 +100,7 @@ enum dma_ctrl_flags { DMA_PREP_PQ_DISABLE_P = (1 << 6), DMA_PREP_PQ_DISABLE_Q = (1 << 7), DMA_PREP_CONTINUE = (1 << 8), + DMA_PREP_FENCE = (1 << 9), }; /** -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/