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| author | Peter Zijlstra <peterz@infradead.org> | 2021-08-15 23:28:47 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2021-08-17 19:04:54 +0200 |
| commit | 843dac28f90ef80535b0aee0b78446f1770c8611 (patch) | |
| tree | b1fe1a179f1477b5bacabf85e4a5f20f2a7a2398 /kernel/locking | |
| parent | 23d599eb2377404100d0d1508e12b0a2c40b49b1 (diff) | |
| download | linux-843dac28f90ef80535b0aee0b78446f1770c8611.tar.gz | |
locking/ww_mutex: Abstract out waiter enqueueing
The upcoming rtmutex based ww_mutex needs a different handling for
enqueueing a waiter. Split it out into a helper function.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211304.566318143@linutronix.de
Diffstat (limited to 'kernel/locking')
| -rw-r--r-- | kernel/locking/ww_mutex.h | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h index 1cd178c0c5c25..f5aaf2f19370e 100644 --- a/kernel/locking/ww_mutex.h +++ b/kernel/locking/ww_mutex.h @@ -44,6 +44,15 @@ __ww_waiter_last(struct mutex *lock) return w; } +static inline void +__ww_waiter_add(struct mutex *lock, struct mutex_waiter *waiter, struct mutex_waiter *pos) +{ + struct list_head *p = &lock->wait_list; + if (pos) + p = &pos->list; + __mutex_add_waiter(lock, waiter, p); +} + /* * Wait-Die: * The newer transactions are killed when: @@ -337,12 +346,11 @@ __ww_mutex_add_waiter(struct mutex_waiter *waiter, struct mutex *lock, struct ww_acquire_ctx *ww_ctx) { - struct mutex_waiter *cur; - struct list_head *pos; + struct mutex_waiter *cur, *pos = NULL; bool is_wait_die; if (!ww_ctx) { - __mutex_add_waiter(lock, waiter, &lock->wait_list); + __ww_waiter_add(lock, waiter, NULL); return 0; } @@ -355,7 +363,6 @@ __ww_mutex_add_waiter(struct mutex_waiter *waiter, * never die here, but they are sorted in stamp order and * may wound the lock holder. */ - pos = &lock->wait_list; for (cur = __ww_waiter_last(lock); cur; cur = __ww_waiter_prev(lock, cur)) { @@ -378,13 +385,13 @@ __ww_mutex_add_waiter(struct mutex_waiter *waiter, break; } - pos = &cur->list; + pos = cur; /* Wait-Die: ensure younger waiters die. */ __ww_mutex_die(lock, cur, ww_ctx); } - __mutex_add_waiter(lock, waiter, pos); + __ww_waiter_add(lock, waiter, pos); /* * Wound-Wait: if we're blocking on a mutex owned by a younger context, |