From 34053979fb1d923217685cf166349f1899980581 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sat, 21 Feb 2009 11:16:36 +0100 Subject: [PATCH] block: cleanup bio_alloc_bioset() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit this warning (which got fixed by commit b2bf968): fs/bio.c: In function ‘bio_alloc_bioset’: fs/bio.c:305: warning: ‘p’ may be used uninitialized in this function Triggered because the code flow in bio_alloc_bioset() is correct but a bit complex for the compiler to see through. Streamline it a bit - this also makes the code a tiny bit more compact: text data bss dec hex filename 7540 256 40 7836 1e9c bio.o.before 7539 256 40 7835 1e9b bio.o.after Also remove an older compiler-warnings annotation from this function, it's not needed. Signed-off-by: Ingo Molnar Signed-off-by: Jens Axboe --- fs/bio.c | 71 +++++++++++++++++++++++++++++--------------------------- 1 file changed, 37 insertions(+), 34 deletions(-) diff --git a/fs/bio.c b/fs/bio.c index d4f06327c810..cef6258b8943 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -301,48 +301,51 @@ void bio_init(struct bio *bio) **/ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) { + struct bio_vec *bvl = NULL; struct bio *bio = NULL; - void *uninitialized_var(p); + unsigned long idx = 0; + void *p = NULL; if (bs) { p = mempool_alloc(bs->bio_pool, gfp_mask); - - if (p) - bio = p + bs->front_pad; - } else + if (!p) + goto err; + bio = p + bs->front_pad; + } else { bio = kmalloc(sizeof(*bio), gfp_mask); + if (!bio) + goto err; + } - if (likely(bio)) { - struct bio_vec *bvl = NULL; - - bio_init(bio); - if (likely(nr_iovecs)) { - unsigned long uninitialized_var(idx); - - if (nr_iovecs <= BIO_INLINE_VECS) { - idx = 0; - bvl = bio->bi_inline_vecs; - nr_iovecs = BIO_INLINE_VECS; - } else { - bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, - bs); - nr_iovecs = bvec_nr_vecs(idx); - } - if (unlikely(!bvl)) { - if (bs) - mempool_free(p, bs->bio_pool); - else - kfree(bio); - bio = NULL; - goto out; - } - bio->bi_flags |= idx << BIO_POOL_OFFSET; - bio->bi_max_vecs = nr_iovecs; - } - bio->bi_io_vec = bvl; + bio_init(bio); + + if (unlikely(!nr_iovecs)) + goto out_set; + + if (nr_iovecs <= BIO_INLINE_VECS) { + bvl = bio->bi_inline_vecs; + nr_iovecs = BIO_INLINE_VECS; + } else { + bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs); + if (unlikely(!bvl)) + goto err_free; + + nr_iovecs = bvec_nr_vecs(idx); } -out: + bio->bi_flags |= idx << BIO_POOL_OFFSET; + bio->bi_max_vecs = nr_iovecs; +out_set: + bio->bi_io_vec = bvl; + return bio; + +err_free: + if (bs) + mempool_free(p, bs->bio_pool); + else + kfree(bio); +err: + return NULL; } struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs) -- 2.34.1