[autobackport: sssd-2-9] Bunch of assorted perf improvements of hot path functions

[sssd-bot]

This is an automatic backport of PR#8447 Bunch of assorted perf improvements of hot path functions to branch sssd-2-9, created by @alexey-tikhonov.

Please make sure this backport is correct.

Note

The commits were cherry-picked without conflicts.

You can push changes to this pull request

git remote add sssd-bot git@github.com:sssd-bot/sssd.git
git fetch sssd-bot refs/heads/SSSD-sssd-backport-pr8447-to-sssd-2-9
git checkout SSSD-sssd-backport-pr8447-to-sssd-2-9
git push sssd-bot SSSD-sssd-backport-pr8447-to-sssd-2-9 --force

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Original commits
09e283e - SDAP: use DEBUG_CONDITIONAL in hot path
9a2cf21 - UTIL: sss_tc_utf8_str_tolower() optimization
a5b77e4 - UTIL: sss_create_internal_fqname() optimization (caching)

Backported commits

• 11a61f5 - SDAP: use DEBUG_CONDITIONAL in hot path
• e8b53e4 - UTIL: sss_tc_utf8_str_tolower() optimization
• 7da25e4 - UTIL: sss_create_internal_fqname() optimization (caching)

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Original Pull Request Body

Those patches are based on a profiling of a following test case:

• users tu1 and tu2 are members of 5k LDAP groups (RFC2307 case, no nested groups)
• SSSD stared with an empty cache
• time id tu1@ldap.test | tr ',' '\n' | wc -l is executed

(Note you need to tweak both LDAP (limits) and SSSD (timeout, client_idle_timeout) settings to make this req complete successfully).

Combined, those patches reduce lookup time on my laptom from ~51+s to ~45-s (at least with debug_microseconds = true)

Note that much more fruitful optimizations are possible under sdap_initgr_common_store(), including getting rid of O(N^2) loop over sdap_get_group_primary_name() in sdap_add_incomplete_groups(), and some of those optimization will make patches in this PR kind of obsolete for this specific test case. But given that those helpers are heavily used across all code base, I think it's still worth consideration.

[gemini-code-assist]

Code Review

This pull request introduces several performance improvements to hot path functions. The changes in sdap.c and sss_tc_utf8.c are good optimizations. However, the caching mechanism introduced in usertools.c for sss_create_internal_fqname has a critical thread-safety issue. It uses static variables without any locking, which can lead to race conditions in a multi-threaded environment like the SSSD backend. I've added a comment with a suggested fix.

[sumit-bose]

Hi,

backport matches the original version, ACK.

bye,
Sumit

[sssd-bot]

The pull request was accepted by @justin-stephenson with the following PR CI status:

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🟢 CodeQL (success)
🟢 rpm-build:centos-stream-9-x86_64:upstream (success)
🟢 Build / make-distcheck (success)
🟢 ci / prepare (success)
🟡 ci / system (centos-9) (in_progress)
🟢 Static code analysis / codeql (success)
🟢 Static code analysis / pre-commit (success)
🟢 Static code analysis / python-system-tests (success)

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There are unsuccessful or unfinished checks. Make sure that the failures are not related to this pull request before merging.

[sssd-bot]

The pull request was accepted by @justin-stephenson with the following PR CI status:

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🟢 CodeQL (success)
🟢 rpm-build:centos-stream-9-x86_64:upstream (success)
➖ Build / make-distcheck (skipped)
➖ ci / prepare (skipped)
➖ ci / system (skipped)
🟢 Static code analysis / codeql (success)
🟢 Static code analysis / pre-commit (success)
🟢 Static code analysis / python-system-tests (success)

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There are unsuccessful or unfinished checks. Make sure that the failures are not related to this pull request before merging.