[PATCH v6 03/17] sched/topology: Split out SD_* flags declaration to its own file

Valentin Schneider
2020-08-17T11:30:28Z

To associate the SD flags with some metadata, we need some more structure
in the way they are declared.

Rather than shove that in a free-standing macro list, move the declaration
in a separate file that can be re-imported with different SD_FLAG
definitions. This is inspired by what is done with the syscall
table (see uapi/asm/unistd.h and sys_call_table).

The value assigned to a given SD flag now depends on the order it appears
in sd_flags.h. No change in functionality.

Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
---
include/linux/sched/sd_flags.h | 35 ++++++++++++++++++++++++++++++++++
include/linux/sched/topology.h | 26 ++++++++++++-------------
2 files changed, 48 insertions(+), 13 deletions(-)
create mode 100644 include/linux/sched/sd_flags.h

diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h
new file mode 100644
index 000000000000..5a74751a1a83
--- /dev/null
+++ b/include/linux/sched/sd_flags.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * sched-domains (multiprocessor balancing) flag declarations.
+ */
+
+#ifndef SD_FLAG
+#error "Incorrect import of SD flags definitions"
+#endif
+
+/* Balance when about to become idle */
+SD_FLAG(SD_BALANCE_NEWIDLE)
+/* Balance on exec */
+SD_FLAG(SD_BALANCE_EXEC)
+/* Balance on fork, clone */
+SD_FLAG(SD_BALANCE_FORK)
+/* Balance on wakeup */
+SD_FLAG(SD_BALANCE_WAKE)
+/* Wake task to waking CPU */
+SD_FLAG(SD_WAKE_AFFINE)
+/* Domain members have different CPU capacities */
+SD_FLAG(SD_ASYM_CPUCAPACITY)
+/* Domain members share CPU capacity */
+SD_FLAG(SD_SHARE_CPUCAPACITY)
+/* Domain members share CPU pkg resources */
+SD_FLAG(SD_SHARE_PKG_RESOURCES)
+/* Only a single load balancing instance */
+SD_FLAG(SD_SERIALIZE)
+/* Place busy groups earlier in the domain */
+SD_FLAG(SD_ASYM_PACKING)
+/* Prefer to place tasks in a sibling domain */
+SD_FLAG(SD_PREFER_SIBLING)
+/* sched_domains of this level overlap */
+SD_FLAG(SD_OVERLAP)
+/* cross-node balancing */
+SD_FLAG(SD_NUMA)
diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h
index 6ec7d7c1d1e3..3e41c0401b5f 100644
--- a/include/linux/sched/topology.h
+++ b/include/linux/sched/topology.h
@@ -11,19 +11,19 @@
*/
#ifdef CONFIG_SMP

-#define SD_BALANCE_NEWIDLE 0x0001 /* Balance when about to become idle */
-#define SD_BALANCE_EXEC 0x0002 /* Balance on exec */
-#define SD_BALANCE_FORK 0x0004 /* Balance on fork, clone */
-#define SD_BALANCE_WAKE 0x0008 /* Balance on wakeup */
-#define SD_WAKE_AFFINE 0x0010 /* Wake task to waking CPU */
-#define SD_ASYM_CPUCAPACITY 0x0020 /* Domain members have different CPU capacities */
-#define SD_SHARE_CPUCAPACITY 0x0040 /* Domain members share CPU capacity */
-#define SD_SHARE_PKG_RESOURCES 0x0080 /* Domain members share CPU pkg resources */
-#define SD_SERIALIZE 0x0100 /* Only a single load balancing instance */
-#define SD_ASYM_PACKING 0x0200 /* Place busy groups earlier in the domain */
-#define SD_PREFER_SIBLING 0x0400 /* Prefer to place tasks in a sibling domain */
-#define SD_OVERLAP 0x0800 /* sched_domains of this level overlap */
-#define SD_NUMA 0x1000 /* cross-node balancing */
+/* Generate SD flag indexes */
+#define SD_FLAG(name) __##name,
+enum {
+ #include <linux/sched/sd_flags.h>
+ __SD_FLAG_CNT,
+};
+#undef SD_FLAG
+/* Generate SD flag bits */
+#define SD_FLAG(name) name = 1 << __##name,
+enum {
+ #include <linux/sched/sd_flags.h>
+};
+#undef SD_FLAG

#ifdef CONFIG_SCHED_SMT
static inline int cpu_smt_flags(void)
--
2.27.0