From patchwork Fri Dec 8 14:53:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patrick Steinhardt X-Patchwork-Id: 13485483 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pks.im header.i=@pks.im header.b="hKQVhEQl"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="P/P7SSAX" Received: from wout5-smtp.messagingengine.com (wout5-smtp.messagingengine.com [64.147.123.21]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A3CC92695 for ; Fri, 8 Dec 2023 06:53:36 -0800 (PST) Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.west.internal (Postfix) with ESMTP id 7BC363200A33; Fri, 8 Dec 2023 09:53:35 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute1.internal (MEProxy); Fri, 08 Dec 2023 09:53:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pks.im; h=cc:cc :content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm1; t=1702047215; x=1702133615; bh=8F 0/oFQqHSzKyZi5t1vp1b2t9e42ME5tkwAbvPgw+vw=; b=hKQVhEQl8wv1+rfMeJ +YJimozOw8sWPBgclqB26Ad/VEoAnOVCNGgSCqzvM4JNelOu/MAZs4IPFO+xghFq fNnXne8xuVLVo0c8+lPQ91GDZCMtunehDlhp3IKt/yLkhQK8EYWfei7SoQqbJjqN T5kx9QOWcNx/8rsICqp/kV4GH004MoGUkvdRv7L6GhQBWG6hcNzYwhomU+vvHJhS zMrupGzeIddXBghw78N9fjN/lg5EMBWr1qhC8EaG0pWw3OoflnWAq0SZeWD0+Rqj xVR+rEwGTd5jPyB0TWwlJ2V/EgH4KzjSC6wCWlZ/RIEnlhSdL2p1Cj1GW2zSde8S cCpg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; t=1702047215; x=1702133615; bh=8F0/oFQqHSzKy Zi5t1vp1b2t9e42ME5tkwAbvPgw+vw=; b=P/P7SSAXgoeaADKZbEgWrqAQMpCJe puHK+sAIaaXiERLDw6xY94ZKxrLJweboKevuil80qcH1ExANup4uIWjDmiZISK0U SzgvlPC5Zo0mDqBbrIr1OdzQQEmqrnQGRUNLSoTnmfQfjm3vaufftqyxqXrRmNLB tvBMAB8Dp/jBe9YOKYAfIsl9a2Ee3BIhBwtkC6uQ8vJG4Vg6eCi/HymO9zXVkYTK P8TswUEY7lFPEehdXDBXYGFfXFNSt3BKKb3X0Sa5W2MSFxcFAQ/f/PT66yZnv2co ZYKEkSwOOa2mWxGF8hsIr4ijeZg/UQxlxnfLvcDg/akB7ub9Sm7ZrhmCA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrudekiedgjedvucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkfhggtggujgesghdtreertddtvdenucfhrhhomheprfgrthhr ihgtkhcuufhtvghinhhhrghrughtuceophhssehpkhhsrdhimheqnecuggftrfgrthhtvg hrnhepueektdevtdffveeljeetgfehheeigeekleduvdeffeeghefgledttdehjeelffet necuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepphhsse hpkhhsrdhimh X-ME-Proxy: Feedback-ID: i197146af:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 8 Dec 2023 09:53:33 -0500 (EST) Received: by vm-mail (OpenSMTPD) with ESMTPSA id 6dcaad72 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Fri, 8 Dec 2023 14:52:02 +0000 (UTC) Date: Fri, 8 Dec 2023 15:53:31 +0100 From: Patrick Steinhardt To: git@vger.kernel.org Cc: Han-Wen Nienhuys , Jonathan Nieder Subject: [PATCH v2 09/11] reftable/merged: reuse buffer to compute record keys Message-ID: References: Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: When iterating over entries in the merged iterator's queue, we compute the key of each of the entries and write it into a buffer. We do not reuse the buffer though and thus re-allocate it on every iteration, which is wasteful given that we never transfer ownership of the allocated bytes outside of the loop. Refactor the code to reuse the buffer. This also fixes a potential memory leak when `merged_iter_advance_subiter()` returns an error. Signed-off-by: Patrick Steinhardt --- reftable/merged.c | 31 ++++++++++++++++--------------- reftable/merged.h | 2 ++ 2 files changed, 18 insertions(+), 15 deletions(-) diff --git a/reftable/merged.c b/reftable/merged.c index 5ded470c08..556bb5c556 100644 --- a/reftable/merged.c +++ b/reftable/merged.c @@ -52,6 +52,8 @@ static void merged_iter_close(void *p) reftable_iterator_destroy(&mi->stack[i]); } reftable_free(mi->stack); + strbuf_release(&mi->key); + strbuf_release(&mi->entry_key); } static int merged_iter_advance_nonnull_subiter(struct merged_iter *mi, @@ -85,7 +87,6 @@ static int merged_iter_advance_subiter(struct merged_iter *mi, size_t idx) static int merged_iter_next_entry(struct merged_iter *mi, struct reftable_record *rec) { - struct strbuf entry_key = STRBUF_INIT; struct pq_entry entry = { 0 }; int err = 0; @@ -105,33 +106,31 @@ static int merged_iter_next_entry(struct merged_iter *mi, such a deployment, the loop below must be changed to collect all entries for the same key, and return new the newest one. */ - reftable_record_key(&entry.rec, &entry_key); + reftable_record_key(&entry.rec, &mi->entry_key); while (!merged_iter_pqueue_is_empty(mi->pq)) { struct pq_entry top = merged_iter_pqueue_top(mi->pq); - struct strbuf k = STRBUF_INIT; - int err = 0, cmp = 0; + int cmp = 0; - reftable_record_key(&top.rec, &k); + reftable_record_key(&top.rec, &mi->key); - cmp = strbuf_cmp(&k, &entry_key); - strbuf_release(&k); - - if (cmp > 0) { + cmp = strbuf_cmp(&mi->key, &mi->entry_key); + if (cmp > 0) break; - } merged_iter_pqueue_remove(&mi->pq); err = merged_iter_advance_subiter(mi, top.index); - if (err < 0) { - return err; - } + if (err < 0) + goto done; reftable_record_release(&top.rec); } reftable_record_copy_from(rec, &entry.rec, hash_size(mi->hash_id)); + +done: reftable_record_release(&entry.rec); - strbuf_release(&entry_key); - return 0; + strbuf_release(&mi->entry_key); + strbuf_release(&mi->key); + return err; } static int merged_iter_next(struct merged_iter *mi, struct reftable_record *rec) @@ -248,6 +247,8 @@ static int merged_table_seek_record(struct reftable_merged_table *mt, .typ = reftable_record_type(rec), .hash_id = mt->hash_id, .suppress_deletions = mt->suppress_deletions, + .key = STRBUF_INIT, + .entry_key = STRBUF_INIT, }; int n = 0; int err = 0; diff --git a/reftable/merged.h b/reftable/merged.h index 7d9f95d27e..d5b39dfe7f 100644 --- a/reftable/merged.h +++ b/reftable/merged.h @@ -31,6 +31,8 @@ struct merged_iter { uint8_t typ; int suppress_deletions; struct merged_iter_pqueue pq; + struct strbuf key; + struct strbuf entry_key; }; void merged_table_release(struct reftable_merged_table *mt);