From: Derrick Stolee <stolee@gmail.com>
To: Elijah Newren <newren@gmail.com>,
Derrick Stolee via GitGitGadget <gitgitgadget@gmail.com>
Cc: Git Mailing List <git@vger.kernel.org>,
Derrick Stolee <derrickstolee@github.com>,
Derrick Stolee <dstolee@microsoft.com>
Subject: Re: [PATCH 1/9] cache-tree: clean up cache_tree_update()
Date: Wed, 20 Jan 2021 14:10:30 -0500 [thread overview]
Message-ID: <bbed0d73-fa9d-92a0-3bc4-1d44263bb2fb@gmail.com> (raw)
In-Reply-To: <CABPp-BFiNvPaAffQ0uBfpkHY1WM2gR3ssvpwzxpDhrZmZZjiDA@mail.gmail.com>
On 1/20/2021 12:21 PM, Elijah Newren wrote:
> On Wed, Jan 20, 2021 at 8:54 AM Derrick Stolee via GitGitGadget
> <gitgitgadget@gmail.com> wrote:...
>> +
>> + if (!istate->cache_tree)
>> + istate->cache_tree = cache_tree();
>
> This is the only substantive change. It seems fairly innocuous, but
> it makes me wonder the reasoning...I don't know/remember enough about
> cache_tree handling to know when this would or wouldn't have already
> been allocated. It seems that this would have had to segfault below
> if istate->cache_tree were ever NULL, and I don't see you mentioning
> any bug you are fixing, so I presume this means you are going to be
> adding new codepaths somewhere that cause this function to be reached
> under different circumstances than previously had been and you need it
> to be more safe for those. Is that correct? Or is it just an
> abundance of caution thing that you're adding? If the latter, any
> reason you chose to allocate one rather than assume it's a violation
> of design invariants and BUG() instead? (Perhaps the commit message
> could add a sentence about the rationale for the extra safety?)
It's something I need in the future when I use the cache_tree_update()
in more places. I think I call it two times, and either I need to
initialize the cache_tree member outside of both, or just make it a
feature of the method that it will re-initialize the cache-tree.
Note: the implementation treats an initialized, but empty cache-tree
as "invalid" so update_one() correctly populates the full tree.
Thanks,
-Stolee
next prev parent reply other threads:[~2021-01-20 19:12 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-20 16:53 [PATCH 0/9] More index cleanups Derrick Stolee via GitGitGadget
2021-01-20 16:53 ` [PATCH 1/9] cache-tree: clean up cache_tree_update() Derrick Stolee via GitGitGadget
2021-01-20 17:21 ` Elijah Newren
2021-01-20 19:10 ` Derrick Stolee [this message]
2021-01-20 16:53 ` [PATCH 2/9] cache-tree: extract subtree_pos() Derrick Stolee via GitGitGadget
2021-01-20 17:23 ` Elijah Newren
2021-01-20 16:53 ` [PATCH 3/9] fsmonitor: de-duplicate BUG()s around dirty bits Derrick Stolee via GitGitGadget
2021-01-20 17:26 ` Elijah Newren
2021-01-21 12:53 ` Chris Torek
2021-01-21 15:56 ` Derrick Stolee
2021-01-20 16:53 ` [PATCH 4/9] repository: add repo reference to index_state Derrick Stolee via GitGitGadget
2021-01-20 17:46 ` Elijah Newren
2021-01-20 19:16 ` Derrick Stolee
2021-01-20 19:50 ` Elijah Newren
2021-01-20 16:53 ` [PATCH 5/9] name-hash: use trace2 regions for init Derrick Stolee via GitGitGadget
2021-01-20 17:47 ` Elijah Newren
2021-01-20 16:53 ` [PATCH 6/9] sparse-checkout: load sparse-checkout patterns Derrick Stolee via GitGitGadget
2021-01-20 17:54 ` Elijah Newren
2021-01-20 16:53 ` [PATCH 7/9] sparse-checkout: hold pattern list in index Derrick Stolee via GitGitGadget
2021-01-20 18:03 ` Elijah Newren
2021-01-20 19:22 ` Derrick Stolee
2021-01-20 16:53 ` [PATCH 8/9] test-lib: test_region looks for trace2 regions Derrick Stolee via GitGitGadget
2021-01-20 18:20 ` Elijah Newren
2021-01-20 19:24 ` Derrick Stolee
2021-01-20 16:53 ` [PATCH 9/9] t1092: test interesting sparse-checkout scenarios Derrick Stolee via GitGitGadget
2021-01-20 19:40 ` Elijah Newren
2021-01-21 11:59 ` Derrick Stolee
2021-01-22 13:03 ` [PATCH v2 0/8] More index cleanups Derrick Stolee via GitGitGadget
2021-01-22 13:03 ` [PATCH v2 1/8] cache-tree: clean up cache_tree_update() Derrick Stolee via GitGitGadget
2021-01-22 19:11 ` Junio C Hamano
2021-01-22 13:03 ` [PATCH v2 2/8] cache-tree: extract subtree_pos() Derrick Stolee via GitGitGadget
2021-01-22 13:03 ` [PATCH v2 3/8] fsmonitor: de-duplicate BUG()s around dirty bits Derrick Stolee via GitGitGadget
2021-01-22 19:18 ` Junio C Hamano
2021-01-22 13:03 ` [PATCH v2 4/8] repository: add repo reference to index_state Derrick Stolee via GitGitGadget
2021-01-22 19:23 ` Junio C Hamano
2021-01-22 13:03 ` [PATCH v2 5/8] name-hash: use trace2 regions for init Derrick Stolee via GitGitGadget
2021-01-22 13:03 ` [PATCH v2 6/8] sparse-checkout: load sparse-checkout patterns Derrick Stolee via GitGitGadget
2021-01-22 13:03 ` [PATCH v2 7/8] test-lib: test_region looks for trace2 regions Derrick Stolee via GitGitGadget
2021-01-22 19:42 ` Junio C Hamano
2021-01-23 18:36 ` Derrick Stolee
2021-01-23 18:50 ` Junio C Hamano
2021-01-22 13:03 ` [PATCH v2 8/8] t1092: test interesting sparse-checkout scenarios Derrick Stolee via GitGitGadget
2021-01-22 19:49 ` [PATCH v2 0/8] More index cleanups Elijah Newren
2021-01-23 18:47 ` Derrick Stolee
2021-01-23 19:58 ` [PATCH v3 0/9] " Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 1/9] cache-tree: clean up cache_tree_update() Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 2/9] cache-tree: simplify verify_cache() prototype Derrick Stolee via GitGitGadget
2021-01-23 20:24 ` Elijah Newren
2021-01-23 21:02 ` Derrick Stolee
2021-01-23 21:10 ` Elijah Newren
2021-01-23 21:41 ` Junio C Hamano
2021-01-23 21:10 ` Junio C Hamano
2021-01-23 21:14 ` Derrick Stolee
2021-01-23 19:58 ` [PATCH v3 3/9] cache-tree: extract subtree_pos() Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 4/9] fsmonitor: de-duplicate BUG()s around dirty bits Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 5/9] repository: add repo reference to index_state Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 6/9] name-hash: use trace2 regions for init Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 7/9] sparse-checkout: load sparse-checkout patterns Derrick Stolee via GitGitGadget
2021-01-23 19:58 ` [PATCH v3 8/9] test-lib: test_region looks for trace2 regions Derrick Stolee via GitGitGadget
2021-01-23 21:07 ` Derrick Stolee
2021-01-23 19:58 ` [PATCH v3 9/9] t1092: test interesting sparse-checkout scenarios Derrick Stolee via GitGitGadget
2021-01-25 18:45 ` Elijah Newren
2021-01-23 20:29 ` [PATCH v3 0/9] More index cleanups Elijah Newren
2021-01-23 21:05 ` Derrick Stolee
2021-01-23 21:42 ` Junio C Hamano
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=bbed0d73-fa9d-92a0-3bc4-1d44263bb2fb@gmail.com \
--to=stolee@gmail.com \
--cc=derrickstolee@github.com \
--cc=dstolee@microsoft.com \
--cc=git@vger.kernel.org \
--cc=gitgitgadget@gmail.com \
--cc=newren@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).