summaryrefslogtreecommitdiff
path: root/include/linux/sched.h
diff options
context:
space:
mode:
authorIulia Manda <iulia.manda21@gmail.com>2014-10-31 02:13:31 +0200
committerIngo Molnar <mingo@kernel.org>2014-11-04 07:17:57 +0100
commit44dba3d5d6a10685fb15bd1954e62016334825e0 (patch)
tree6a0c9b0c34225a78263212037c69c87e97905211 /include/linux/sched.h
parentcad3bb32e181c286c46ec12b2deb1f26a6f9835d (diff)
sched: Refactor task_struct to use numa_faults instead of numa_* pointers
This patch simplifies task_struct by removing the four numa_* pointers in the same array and replacing them with the array pointer. By doing this, on x86_64, the size of task_struct is reduced by 3 ulong pointers (24 bytes on x86_64). A new parameter is added to the task_faults_idx function so that it can return an index to the correct offset, corresponding with the old precalculated pointers. All of the code in sched/ that depended on task_faults_idx and numa_* was changed in order to match the new logic. Signed-off-by: Iulia Manda <iulia.manda21@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: mgorman@suse.de Cc: dave@stgolabs.net Cc: riel@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20141031001331.GA30662@winterfell Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/sched.h')
-rw-r--r--include/linux/sched.h31
1 files changed, 13 insertions, 18 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4400ddc2fe73..bd7c14ba86c4 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1597,28 +1597,23 @@ struct task_struct {
struct numa_group *numa_group;
/*
- * Exponential decaying average of faults on a per-node basis.
- * Scheduling placement decisions are made based on the these counts.
- * The values remain static for the duration of a PTE scan
+ * numa_faults is an array split into four regions:
+ * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
+ * in this precise order.
+ *
+ * faults_memory: Exponential decaying average of faults on a per-node
+ * basis. Scheduling placement decisions are made based on these
+ * counts. The values remain static for the duration of a PTE scan.
+ * faults_cpu: Track the nodes the process was running on when a NUMA
+ * hinting fault was incurred.
+ * faults_memory_buffer and faults_cpu_buffer: Record faults per node
+ * during the current scan window. When the scan completes, the counts
+ * in faults_memory and faults_cpu decay and these values are copied.
*/
- unsigned long *numa_faults_memory;
+ unsigned long *numa_faults;
unsigned long total_numa_faults;
/*
- * numa_faults_buffer records faults per node during the current
- * scan window. When the scan completes, the counts in
- * numa_faults_memory decay and these values are copied.
- */
- unsigned long *numa_faults_buffer_memory;
-
- /*
- * Track the nodes the process was running on when a NUMA hinting
- * fault was incurred.
- */
- unsigned long *numa_faults_cpu;
- unsigned long *numa_faults_buffer_cpu;
-
- /*
* numa_faults_locality tracks if faults recorded during the last
* scan window were remote/local. The task scan period is adapted
* based on the locality of the faults with different weights