Where XHLOCK_{SOFT,HARD} are save/restore points in the xhlocks[] to ensure the temporal IRQ events don't interact with task state, the XHLOCK_PROC is a fundament different beast that just happens to share the interface. The purpose of XHLOCK_PROC is to annotate independent execution inside one task. For example workqueues, each work should appear to run in its own 'pristine' 'task'. Remove XHLOCK_PROC in favour of its own interface to avoid confusion.
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| @@ -2094,8 +2094,8 @@ __acquires(&pool->lock) · 2093 unmodified lines | ||
| 2094 | 2094 | lock_map_acquire(&pwq->wq->lockdep_map); |
| 2095 | 2095 | lock_map_acquire(&lockdep_map); |
| 2096 | 2096 | /* |
| 2097 | − * Strictly speaking we should do start(PROC) without holding any | |
| 2098 | − * locks, that is, before these two lock_map_acquire()'s. | |
| 2097 | + * Strictly speaking we should mark the invariant state without holding | |
| 2098 | + * any locks, that is, before these two lock_map_acquire()'s. | |
| 2099 | 2099 | * |
| 2100 | 2100 | * However, that would result in: |
| 2101 | 2101 | * |
| @@ -2107,14 +2107,14 @@ __acquires(&pool->lock) · 5 unmodified lines | ||
| 2107 | 2107 | * Which would create W1->C->W1 dependencies, even though there is no |
| 2108 | 2108 | * actual deadlock possible. There are two solutions, using a |
| 2109 | 2109 | * read-recursive acquire on the work(queue) 'locks', but this will then |
| 2110 | − * hit the lockdep limitation on recursive locks, or simly discard | |
| 2110 | + * hit the lockdep limitation on recursive locks, or simply discard | |
| 2111 | 2111 | * these locks. |
| 2112 | 2112 | * |
| 2113 | 2113 | * AFAICT there is no possible deadlock scenario between the |
| 2114 | 2114 | * flush_work() and complete() primitives (except for single-threaded |
| 2115 | 2115 | * workqueues), so hiding them isn't a problem. |
| 2116 | 2116 | */ |
| 2117 | − crossrelease_hist_start(XHLOCK_PROC, true); | |
| 2117 | + lockdep_invariant_state(true); | |
| 2118 | 2118 | trace_workqueue_execute_start(work); |
| 2119 | 2119 | worker->current_func(work); |
| 2120 | 2120 | /* |
| @@ -2122,7 +2122,6 @@ __acquires(&pool->lock) · 1 unmodified line | ||
| 2122 | 2122 | * point will only record its address. |
| 2123 | 2123 | */ |
| 2124 | 2124 | trace_workqueue_execute_end(work); |
| 2125 | − crossrelease_hist_end(XHLOCK_PROC); | |
| 2126 | 2125 | lock_map_release(&lockdep_map); |
| 2127 | 2126 | lock_map_release(&pwq->wq->lockdep_map); |
| 2128 | 2127 | |