lkml.org 
[lkml]   [2015]   [May]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 6/7 V2] workqueue: reuse wq_update_unbound_numa_attrs_buf as temporary attrs
Date
tmp_attrs is just temporary attrs, we can use wq_update_unbound_numa_attrs_buf
for it like wq_update_unbound_numa();

This change also avoids frequently alloc/free the tmp_attrs when
the low level cpumask is being updated.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
kernel/workqueue.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 61f8ace..6426d6e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -295,7 +295,7 @@ module_param_named(power_efficient, wq_power_efficient, bool, 0444);

static bool wq_numa_enabled; /* unbound NUMA affinity enabled */

-/* buf for wq_update_unbound_numa_attrs(), protected by CPU hotplug exclusion */
+/* PL: buf for apply_wqattrs_prepare() and wq_update_unbound_numa() */
static struct workqueue_attrs *wq_update_unbound_numa_attrs_buf;

static DEFINE_MUTEX(wq_pool_mutex); /* protects pools and workqueues list */
@@ -3561,11 +3561,16 @@ apply_wqattrs_prepare(struct workqueue_struct *wq,
GFP_KERNEL);

new_attrs = alloc_workqueue_attrs(GFP_KERNEL);
- tmp_attrs = alloc_workqueue_attrs(GFP_KERNEL);
- if (!ctx || !new_attrs || !tmp_attrs)
+ if (!ctx || !new_attrs)
goto out_free;

/*
+ * We don't need to alloc/free temporary attrs. Let's use a
+ * preallocated one. The following buf is protected by wq_pool_mutex.
+ */
+ tmp_attrs = wq_update_unbound_numa_attrs_buf;
+
+ /*
* Calculate the attrs of the default pwq.
* If the user configured cpumask doesn't overlap with the
* wq_unbound_cpumask, we fallback to the wq_unbound_cpumask.
@@ -3615,11 +3620,9 @@ apply_wqattrs_prepare(struct workqueue_struct *wq,
ctx->attrs = new_attrs;

ctx->wq = wq;
- free_workqueue_attrs(tmp_attrs);
return ctx;

out_free:
- free_workqueue_attrs(tmp_attrs);
free_workqueue_attrs(new_attrs);
apply_wqattrs_cleanup(ctx);
return NULL;
@@ -3741,7 +3744,7 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
/*
* We don't wanna alloc/free wq_attrs for each wq for each CPU.
* Let's use a preallocated one. The following buf is protected by
- * CPU hotplug exclusion.
+ * wq_pool_mutex.
*/
target_attrs = wq_update_unbound_numa_attrs_buf;
cpumask = target_attrs->cpumask;
--
2.1.0


\
 
 \ /
  Last update: 2015-05-12 14:41    [W:0.131 / U:0.944 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site