[PATCH] ida: Remove simple_ida_lock
From: Matthew Wilcox
Date: Sat Mar 31 2018 - 08:53:44 EST
From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
Improve the scalability of the IDA by using the per-IDA xa_lock rather
than the global simple_ida_lock. IDAs are not typically used in
performance-sensitive locations, but since we have this lock anyway,
we can use it. It is also a step towards converting the IDA from the
radix tree to the XArray.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
lib/idr.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/lib/idr.c b/lib/idr.c
index b2f7ab31ce55..e80da084117c 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -7,7 +7,6 @@
#include <linux/xarray.h>
DEFINE_PER_CPU(struct ida_bitmap *, ida_bitmap);
-static DEFINE_SPINLOCK(simple_ida_lock);
/**
* idr_alloc_u32() - Allocate an ID.
@@ -572,7 +571,7 @@ int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
if (!ida_pre_get(ida, gfp_mask))
return -ENOMEM;
- spin_lock_irqsave(&simple_ida_lock, flags);
+ xa_lock_irqsave(&ida->ida_rt, flags);
ret = ida_get_new_above(ida, start, &id);
if (!ret) {
if (id > max) {
@@ -582,7 +581,7 @@ int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
ret = id;
}
}
- spin_unlock_irqrestore(&simple_ida_lock, flags);
+ xa_unlock_irqrestore(&ida->ida_rt, flags);
if (unlikely(ret == -EAGAIN))
goto again;
@@ -606,8 +605,8 @@ void ida_simple_remove(struct ida *ida, unsigned int id)
unsigned long flags;
BUG_ON((int)id < 0);
- spin_lock_irqsave(&simple_ida_lock, flags);
+ xa_lock_irqsave(&ida->ida_rt, flags);
ida_remove(ida, id);
- spin_unlock_irqrestore(&simple_ida_lock, flags);
+ xa_unlock_irqrestore(&ida->ida_rt, flags);
}
EXPORT_SYMBOL(ida_simple_remove);
--
2.16.2