Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933083AbbEEUDZ (ORCPT ); Tue, 5 May 2015 16:03:25 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:21558 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933040AbbEEUDK (ORCPT ); Tue, 5 May 2015 16:03:10 -0400 From: Jens Axboe To: , CC: , , Jens Axboe Subject: [PATCH 1/7] block: add support for carrying a stream ID in a bio Date: Tue, 5 May 2015 14:02:55 -0600 Message-ID: <1430856181-19568-2-git-send-email-axboe@fb.com> X-Mailer: git-send-email 2.4.0.rc2.1.g3d6bc9a In-Reply-To: <1430856181-19568-1-git-send-email-axboe@fb.com> References: <1430856181-19568-1-git-send-email-axboe@fb.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.54.13] X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.14.151,1.0.33,0.0.0000 definitions=2015-05-05_06:2015-05-05,2015-05-05,1970-01-01 signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2965 Lines: 97 The top bits of bio->bi_flags are reserved for keeping the allocation pool, set aside the next eight bits for carrying a stream ID. That leaves us with support for 255 streams, 0 is reserved as a "stream not set" value. Add helpers for setting/getting stream ID of a bio. Signed-off-by: Jens Axboe --- block/bio.c | 2 ++ block/blk-core.c | 3 +++ include/linux/blk_types.h | 28 +++++++++++++++++++++++++++- 3 files changed, 32 insertions(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index f66a4eae16ee..1cd3d745047c 100644 --- a/block/bio.c +++ b/block/bio.c @@ -567,6 +567,7 @@ void __bio_clone_fast(struct bio *bio, struct bio *bio_src) bio->bi_rw = bio_src->bi_rw; bio->bi_iter = bio_src->bi_iter; bio->bi_io_vec = bio_src->bi_io_vec; + bio_set_streamid(bio, bio_get_streamid(bio_src)); } EXPORT_SYMBOL(__bio_clone_fast); @@ -672,6 +673,7 @@ integrity_clone: } } + bio_set_streamid(bio, bio_get_streamid(bio_src)); return bio; } EXPORT_SYMBOL(bio_clone_bioset); diff --git a/block/blk-core.c b/block/blk-core.c index fd154b94447a..6276ce1ad46b 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1941,6 +1941,9 @@ void generic_make_request(struct bio *bio) do { struct request_queue *q = bdev_get_queue(bio->bi_bdev); + if (bio_streamid_valid(bio)) + blk_add_trace_msg(q, "StreamID=%u", bio_get_streamid(bio)); + q->make_request_fn(q, bio); bio = bio_list_pop(current->bio_list); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index a1b25e35ea5f..0678c7baa7b1 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -138,9 +138,35 @@ struct bio { #define BIO_POOL_BITS (4) #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) -#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) +/* + * after the pool bits, next 8 bits are for the stream id + */ +#define BIO_STREAM_BITS (8) +#define BIO_STREAM_OFFSET (BIO_POOL_OFFSET - BIO_STREAM_BITS) +#define BIO_STREAM_MASK ((1 << BIO_STREAM_BITS) - 1) + +static inline unsigned long streamid_to_flags(unsigned int id) +{ + return (unsigned long) (id & BIO_STREAM_MASK) << BIO_STREAM_OFFSET; +} + +static inline void bio_set_streamid(struct bio *bio, unsigned int id) +{ + bio->bi_flags |= streamid_to_flags(id); +} + +static inline unsigned int bio_get_streamid(struct bio *bio) +{ + return (bio->bi_flags >> BIO_STREAM_OFFSET) & BIO_STREAM_MASK; +} + +static inline bool bio_streamid_valid(struct bio *bio) +{ + return bio_get_streamid(bio) != 0; +} + #endif /* CONFIG_BLOCK */ /* -- 2.4.0.rc2.1.g3d6bc9a -- 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/