diff options
| author |   Matthew Wilcox <willy@infradead.org> | 2018-10-30 09:45:55 -0400 |
|---|---|---|
| committer | Matthew Wilcox <willy@infradead.org> | 2018-11-05 16:38:08 -0500 |
| commit | 4c0608f4a0e76dfb82d3accd20081f4bf47ed143 (patch) | |
| tree | 54a22dbdebdd23830ea5c9f88c78cdc8567f2fef /lib | |
| parent | nilfs2: Use xa_erase_irq (diff) | |
| download | linux-dev-4c0608f4a0e76dfb82d3accd20081f4bf47ed143.tar.xz linux-dev-4c0608f4a0e76dfb82d3accd20081f4bf47ed143.zip | |
XArray: Regularise xa_reserve
The xa_reserve() function was a little unusual in that it attempted to
be callable for all kinds of locking scenarios. Make it look like the
other APIs with __xa_reserve, xa_reserve_bh and xa_reserve_irq variants.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/test_xarray.c | 6 | ||||
| -rw-r--r-- | lib/xarray.c | 18 |
2 files changed, 13 insertions, 11 deletions
diff --git a/lib/test_xarray.c b/lib/test_xarray.c index 126127658b49..e5294b20b52f 100644 --- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -373,6 +373,12 @@ static noinline void check_reserve(struct xarray *xa) xa_erase_index(xa, 12345678); XA_BUG_ON(xa, !xa_empty(xa)); + /* And so does xa_insert */ + xa_reserve(xa, 12345678, GFP_KERNEL); + XA_BUG_ON(xa, xa_insert(xa, 12345678, xa_mk_value(12345678), 0) != 0); + xa_erase_index(xa, 12345678); + XA_BUG_ON(xa, !xa_empty(xa)); + /* Can iterate through a reserved entry */ xa_store_index(xa, 5, GFP_KERNEL); xa_reserve(xa, 6, GFP_KERNEL); diff --git a/lib/xarray.c b/lib/xarray.c index e7be4e47c6a9..9cab8cfef8a8 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1488,7 +1488,7 @@ void *__xa_cmpxchg(struct xarray *xa, unsigned long index, EXPORT_SYMBOL(__xa_cmpxchg); /** - * xa_reserve() - Reserve this index in the XArray. + * __xa_reserve() - Reserve this index in the XArray. * @xa: XArray. * @index: Index into array. * @gfp: Memory allocation flags. @@ -1496,33 +1496,29 @@ EXPORT_SYMBOL(__xa_cmpxchg); * Ensures there is somewhere to store an entry at @index in the array. * If there is already something stored at @index, this function does * nothing. If there was nothing there, the entry is marked as reserved. - * Loads from @index will continue to see a %NULL pointer until a - * subsequent store to @index. + * Loading from a reserved entry returns a %NULL pointer. * * If you do not use the entry that you have reserved, call xa_release() * or xa_erase() to free any unnecessary memory. * - * Context: Process context. Takes and releases the xa_lock, IRQ or BH safe - * if specified in XArray flags. May sleep if the @gfp flags permit. + * Context: Any context. Expects the xa_lock to be held on entry. May + * release the lock, sleep and reacquire the lock if the @gfp flags permit. * Return: 0 if the reservation succeeded or -ENOMEM if it failed. */ -int xa_reserve(struct xarray *xa, unsigned long index, gfp_t gfp) +int __xa_reserve(struct xarray *xa, unsigned long index, gfp_t gfp) { XA_STATE(xas, xa, index); - unsigned int lock_type = xa_lock_type(xa); void *curr; do { - xas_lock_type(&xas, lock_type); curr = xas_load(&xas); if (!curr) xas_store(&xas, XA_ZERO_ENTRY); - xas_unlock_type(&xas, lock_type); - } while (xas_nomem(&xas, gfp)); + } while (__xas_nomem(&xas, gfp)); return xas_error(&xas); } -EXPORT_SYMBOL(xa_reserve); +EXPORT_SYMBOL(__xa_reserve); #ifdef CONFIG_XARRAY_MULTI static void xas_set_range(struct xa_state *xas, unsigned long first, |