gpui: Fix deadlock in performance profiler and reenable it - #61584
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Upstream changes (zed-industries/zed main, 27 commits): - agent: Add agent.compaction_model setting for context compaction (zed-industries#60012) - agent: Show effort selector for anthropic compatible providers (zed-industries#61579) - acp: Update agent-client-protocol SDK to 2.0.0 (zed-industries#61570) - client: Extract proxy handshakes into new proxy_handshake crate (zed-industries#61427) - collab: Fix multiworkspace location out of sync bugs (zed-industries#61598) - editor: Fix sticky header drag cancels autoscroll (zed-industries#53592) - editor: Fix crash when copying and pasting using multiple cursors (zed-industries#61545) - editor: Skip untitled buffers when saving a multi-buffer (zed-industries#61380) - gpui: Fix images not being drawn with rounded corners with ObjectFit::Cover (zed-industries#61383) - gpui: Fix deadlock in performance profiler and reenable it (zed-industries#61584) - git_ui: Prevent Git panel bindings in repository selector (zed-industries#61282) - language_model: Add explicit OpenAI conversation compaction and fix Anthropic compaction (zed-industries#61370) - markdown: Fix squashed Mermaid diagrams in markdown preview (zed-industries#61260) - Opus 5 BYOK Support (zed-industries#61596) - repl: Show add-cell controls in empty notebooks (zed-industries#61329) - search: Escape seeded buffer search query in regex mode (zed-industries#57748) - settings: Fix VS Code import appending duplicate file associations (zed-industries#61355) - settings: Split VSCode and Zed keymap files (zed-industries#61532) - Treat blank spawn_agent session IDs as absent (zed-industries#60893) - worktree: Reload git state when a watcher rescan covers a repository (zed-industries#61541) - Plus 7 more minor fixes. Merge fixes: - crates/agent/src/thread.rs: replay_tool_call used 'message_ix' (undefined) after auto-merge; renamed to 'owning_message_ix' (the parameter name). - Cargo.toml: Removed stale workspace members hkask-wallet and hkask-git-cas (both directories deleted in prior commits but workspace entries remained). - kask/crates/hkask-regulation/src/wallet_manager.rs: Stubbed consume() and settle_rjoules() on WalletBudgetPort — these were API-key encumbrance operations from the deleted hkask-wallet crate; regulation tracks per-agent gas balances, not per-key encumbrances. - kask/crates/hkask-regulation/src/wallet_gas_calibrator.rs: Fixed test to use crate::agent_wallet_store::WalletStore instead of hkask_storage::WalletStore. - kask/crates/hkask-regulation/Cargo.toml: Added tokio macros feature to dev-dependencies for #[tokio::test]. - kask/crates/kask_bridge/Cargo.toml: Added futures dependency (needed by context_injector.rs for futures::executor::block_on). - kask/crates/kask_bridge/src/context_injector.rs: Fixed futures_util::executor to futures::executor (futures-util doesn't include executor module). Release Notes: - N/A
0arm
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Jul 26, 2026
…tries#61584) ### Summary PR zed-industries#58942 disabled the performance profiler within Zed because there was a race condition that caused Zed to hang forever due to a deadlock involving the foreground thread. This PR fixes the deadlock and re-enables the performance profiler. The deadlock happened because `ThreadTimings::drop()` locks `GLOBAL_THREAD_TIMINGS`, and that drop could run in places where `GLOBAL_THREAD_TIMINGS` was already locked: the collection paths (`get_all_timings`, `take_all_stats`, `set_trace_enabled(false)`) held the global lock while upgrading and then dropping per-thread `Arc<GuardedTaskTimings>` handles. If a worker thread exited in that window (e.g. GCD reclaiming an idle thread), the collector inherited the last strong reference, and dropping it ran `ThreadTimings::drop` -> `GLOBAL_THREAD_TIMINGS.lock()` reentrantly on the same thread. The spinlock is not reentrant, so the thread spun forever while holding the lock, hanging every other thread that touched the profiler. The fix: hold `GLOBAL_THREAD_TIMINGS` only long enough to upgrade the `Weak` handles (`upgraded_thread_timings()`), and release it before any per-thread buffer is locked, copied, or dropped. A last-reference drop now always runs with the global lock free. As a side benefit, the up-to-16MiB per-thread buffer copies no longer happen under the global lock. ### Diagram ```mermaid sequenceDiagram participant C as Collector thread (get_all_timings) participant G as GLOBAL_THREAD_TIMINGS (spin::Mutex) participant T as Worker thread (exiting) Note over T: holds the only strong Arc<br/>in its THREAD_TIMINGS TLS C->>G: lock() — guard held for entire collection C->>C: Weak::upgrade() (strong: 1 → 2) T->>T: thread exits, TLS destructor drops its Arc (strong: 2 → 1) C->>C: temp Arc dropped at end of iteration (strong: 1 → 0) C->>C: ThreadTimings::drop() runs on collector thread C->>G: lock() again — already held by this thread Note over C,G: spin lock is not reentrant → spins forever,<br/>every other profiler user spins behind it Note over C,T: Fix: upgrade all Weaks under the lock, release it,<br/>then lock/copy/drop per-thread handles — the reentrant<br/>drop can now only ever run with the global lock free ``` Release Notes: - Fixed a deadlock in the performance profiler and re-enabled it (`zed: open performance profiler`)
jolutz
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Aug 8, 2026
…tries#61584) ### Summary PR zed-industries#58942 disabled the performance profiler within Zed because there was a race condition that caused Zed to hang forever due to a deadlock involving the foreground thread. This PR fixes the deadlock and re-enables the performance profiler. The deadlock happened because `ThreadTimings::drop()` locks `GLOBAL_THREAD_TIMINGS`, and that drop could run in places where `GLOBAL_THREAD_TIMINGS` was already locked: the collection paths (`get_all_timings`, `take_all_stats`, `set_trace_enabled(false)`) held the global lock while upgrading and then dropping per-thread `Arc<GuardedTaskTimings>` handles. If a worker thread exited in that window (e.g. GCD reclaiming an idle thread), the collector inherited the last strong reference, and dropping it ran `ThreadTimings::drop` -> `GLOBAL_THREAD_TIMINGS.lock()` reentrantly on the same thread. The spinlock is not reentrant, so the thread spun forever while holding the lock, hanging every other thread that touched the profiler. The fix: hold `GLOBAL_THREAD_TIMINGS` only long enough to upgrade the `Weak` handles (`upgraded_thread_timings()`), and release it before any per-thread buffer is locked, copied, or dropped. A last-reference drop now always runs with the global lock free. As a side benefit, the up-to-16MiB per-thread buffer copies no longer happen under the global lock. ### Diagram ```mermaid sequenceDiagram participant C as Collector thread (get_all_timings) participant G as GLOBAL_THREAD_TIMINGS (spin::Mutex) participant T as Worker thread (exiting) Note over T: holds the only strong Arc<br/>in its THREAD_TIMINGS TLS C->>G: lock() — guard held for entire collection C->>C: Weak::upgrade() (strong: 1 → 2) T->>T: thread exits, TLS destructor drops its Arc (strong: 2 → 1) C->>C: temp Arc dropped at end of iteration (strong: 1 → 0) C->>C: ThreadTimings::drop() runs on collector thread C->>G: lock() again — already held by this thread Note over C,G: spin lock is not reentrant → spins forever,<br/>every other profiler user spins behind it Note over C,T: Fix: upgrade all Weaks under the lock, release it,<br/>then lock/copy/drop per-thread handles — the reentrant<br/>drop can now only ever run with the global lock free ``` Release Notes: - Fixed a deadlock in the performance profiler and re-enabled it (`zed: open performance profiler`)
playdohface
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Aug 29, 2026
…tries#61584) ### Summary PR zed-industries#58942 disabled the performance profiler within Zed because there was a race condition that caused Zed to hang forever due to a deadlock involving the foreground thread. This PR fixes the deadlock and re-enables the performance profiler. The deadlock happened because `ThreadTimings::drop()` locks `GLOBAL_THREAD_TIMINGS`, and that drop could run in places where `GLOBAL_THREAD_TIMINGS` was already locked: the collection paths (`get_all_timings`, `take_all_stats`, `set_trace_enabled(false)`) held the global lock while upgrading and then dropping per-thread `Arc<GuardedTaskTimings>` handles. If a worker thread exited in that window (e.g. GCD reclaiming an idle thread), the collector inherited the last strong reference, and dropping it ran `ThreadTimings::drop` -> `GLOBAL_THREAD_TIMINGS.lock()` reentrantly on the same thread. The spinlock is not reentrant, so the thread spun forever while holding the lock, hanging every other thread that touched the profiler. The fix: hold `GLOBAL_THREAD_TIMINGS` only long enough to upgrade the `Weak` handles (`upgraded_thread_timings()`), and release it before any per-thread buffer is locked, copied, or dropped. A last-reference drop now always runs with the global lock free. As a side benefit, the up-to-16MiB per-thread buffer copies no longer happen under the global lock. ### Diagram ```mermaid sequenceDiagram participant C as Collector thread (get_all_timings) participant G as GLOBAL_THREAD_TIMINGS (spin::Mutex) participant T as Worker thread (exiting) Note over T: holds the only strong Arc<br/>in its THREAD_TIMINGS TLS C->>G: lock() — guard held for entire collection C->>C: Weak::upgrade() (strong: 1 → 2) T->>T: thread exits, TLS destructor drops its Arc (strong: 2 → 1) C->>C: temp Arc dropped at end of iteration (strong: 1 → 0) C->>C: ThreadTimings::drop() runs on collector thread C->>G: lock() again — already held by this thread Note over C,G: spin lock is not reentrant → spins forever,<br/>every other profiler user spins behind it Note over C,T: Fix: upgrade all Weaks under the lock, release it,<br/>then lock/copy/drop per-thread handles — the reentrant<br/>drop can now only ever run with the global lock free ``` Release Notes: - Fixed a deadlock in the performance profiler and re-enabled it (`zed: open performance profiler`)
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Summary
PR #58942 disabled the performance profiler within Zed because there was a race condition that caused Zed to hang forever due to a deadlock involving the foreground thread. This PR fixes the deadlock and re-enables the performance profiler.
The deadlock happened because
ThreadTimings::drop()locksGLOBAL_THREAD_TIMINGS, and that drop could run in places whereGLOBAL_THREAD_TIMINGSwas already locked: the collection paths (get_all_timings,take_all_stats,set_trace_enabled(false)) held the global lock while upgrading and then dropping per-threadArc<GuardedTaskTimings>handles. If a worker thread exited in that window (e.g. GCD reclaiming an idle thread), the collector inherited the last strong reference, and dropping it ranThreadTimings::drop->GLOBAL_THREAD_TIMINGS.lock()reentrantly on the same thread. The spinlock is not reentrant, so the thread spun forever while holding the lock, hanging every other thread that touched the profiler.The fix: hold
GLOBAL_THREAD_TIMINGSonly long enough to upgrade theWeakhandles (upgraded_thread_timings()), and release it before any per-thread buffer is locked, copied, or dropped. A last-reference drop now always runs with the global lock free. As a side benefit, the up-to-16MiB per-thread buffer copies no longer happen under the global lock.Diagram
sequenceDiagram participant C as Collector thread (get_all_timings) participant G as GLOBAL_THREAD_TIMINGS (spin::Mutex) participant T as Worker thread (exiting) Note over T: holds the only strong Arc<br/>in its THREAD_TIMINGS TLS C->>G: lock() — guard held for entire collection C->>C: Weak::upgrade() (strong: 1 → 2) T->>T: thread exits, TLS destructor drops its Arc (strong: 2 → 1) C->>C: temp Arc dropped at end of iteration (strong: 1 → 0) C->>C: ThreadTimings::drop() runs on collector thread C->>G: lock() again — already held by this thread Note over C,G: spin lock is not reentrant → spins forever,<br/>every other profiler user spins behind it Note over C,T: Fix: upgrade all Weaks under the lock, release it,<br/>then lock/copy/drop per-thread handles — the reentrant<br/>drop can now only ever run with the global lock freeRelease Notes:
zed: open performance profiler)