| 1 | package sessioncatalog |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "path/filepath" |
| 6 | "time" |
| 7 | ) |
| 8 | |
| 9 | // RequestIndexSession coalesces an authoritative session write by path. A full |
| 10 | // queue journals a root invalidation before returning; notification consumers |
| 11 | // must use TryRequestIndexSession and coalesce overflow at their own boundary. |
| 12 | func (c *Catalog) RequestIndexSession(target DirectoryTarget, path string) bool { |
| 13 | if c == nil || cleanCatalogAccessPath(path) == "" { |
| 14 | return false |
| 15 | } |
| 16 | if c.TryRequestIndexSession(target, path) { |
| 17 | return true |
| 18 | } |
| 19 | if target.Path == "" { |
| 20 | target.Path = filepath.Dir(cleanCatalogAccessPath(path)) |
| 21 | } |
| 22 | // Losing a wake-up must not lose the authoritative write. The root |
| 23 | // queue coalesces overflow and retains it until reconciliation. |
| 24 | c.RequestReconcile(target) |
| 25 | return false |
| 26 | } |
| 27 | |
| 28 | // TryRequestIndexSession never waits for filesystem or database work. On false |
| 29 | // the caller owns the root invalidation, including retrying failed journal |
| 30 | // admission. This lets filesystem consumers drain bursts without doing one |
| 31 | // synchronous journal transaction for every overflowing file notification. |
| 32 | func (c *Catalog) TryRequestIndexSession(target DirectoryTarget, path string) bool { |
| 33 | if c == nil { |
| 34 | return false |
| 35 | } |
| 36 | path = cleanCatalogAccessPath(path) |
| 37 | if path == "" { |
| 38 | return false |
| 39 | } |
| 40 | target.Path = cleanCatalogAccessPath(target.Path) |
| 41 | if target.Path == "" { |
| 42 | target.Path = filepath.Dir(path) |
| 43 | } |
| 44 | key := queuePathKey(path) |
| 45 | request := sessionPathRequest{target: target, path: path, queueKey: key, sequence: c.mutationSeq.Add(1)} |
| 46 | c.pathQueueMu.Lock() |
| 47 | if _, loaded := c.pathQueued.Load(key); loaded { |
| 48 | c.pathQueued.Store(key, request) |
| 49 | c.pathQueueMu.Unlock() |
| 50 | return true |
| 51 | } |
| 52 | c.pathQueued.Store(key, request) |
| 53 | select { |
| 54 | case c.pathCh <- request: |
| 55 | c.pathQueueMu.Unlock() |
| 56 | return true |
| 57 | case <-c.stop: |
| 58 | c.pathQueued.Delete(key) |
| 59 | c.pathQueueMu.Unlock() |
| 60 | return false |
| 61 | default: |
| 62 | c.pathQueued.Delete(key) |
| 63 | c.pathQueueMu.Unlock() |
| 64 | return false |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | func (c *Catalog) sessionPathLoop() { |
| 69 | defer c.workers.Done() |
| 70 | for { |
| 71 | select { |
| 72 | case token := <-c.pathCh: |
| 73 | c.pathQueueMu.Lock() |
| 74 | queued, ok := c.pathQueued.LoadAndDelete(token.queueKey) |
| 75 | c.pathQueueMu.Unlock() |
| 76 | if !ok { |
| 77 | continue |
| 78 | } |
| 79 | request := queued.(sessionPathRequest) |
| 80 | ctx, cancel := context.WithTimeout(c.workerCtx, 30*time.Second) |
| 81 | _ = c.indexSessionPath(ctx, request.target, request.path, request.sequence) |
| 82 | cancel() |
| 83 | case <-c.stop: |
| 84 | return |
| 85 | } |
| 86 | } |
| 87 | } |
| 88 |