[PATCH 2/2] sched_ext: scx_qmap: Read SCX_RESCUE_DISABLE through the enum lookup tables

[Tejun Heo]

788b494fab1c ("sched_ext: scx_qmap: Drop the compat code") left one compat
lookup behind: the -B 0 case reads SCX_RESCUE_DISABLE with
__COMPAT_ENUM_OR_ZERO(). Userspace can read SCX_RESCUE_DISABLE only from BTF
as it is in the kernel-internal enum scx_consts. The enum lookup tables
already read their entries from BTF for every scheduler at open time.

Add SCX_RESCUE_DISABLE to the lookup tables and read it from the skeleton's
rodata. No behavior change.

Suggested-by: Andrea Righi <arighi@xxxxxxxxxx>
Link: https://lore.kernel.org/all/ataTuzRFTRm_pax6@gpd4/
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
 tools/sched_ext/include/scx/enums.autogen.bpf.h | 3 +++
 tools/sched_ext/include/scx/enums.autogen.h     | 1 +
 tools/sched_ext/scx_qmap.c                      | 2 +-
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/sched_ext/include/scx/enums.autogen.bpf.h b/tools/sched_ext/include/scx/enums.autogen.bpf.h
index 405a3e6b8f33..d0c37018659e 100644
--- a/tools/sched_ext/include/scx/enums.autogen.bpf.h
+++ b/tools/sched_ext/include/scx/enums.autogen.bpf.h
@@ -13,6 +13,9 @@ const volatile u64 __SCX_SLICE_DFL __weak;
 const volatile u64 __SCX_SLICE_INF __weak;
 #define SCX_SLICE_INF __SCX_SLICE_INF
 
+const volatile u64 __SCX_RESCUE_DISABLE __weak;
+#define SCX_RESCUE_DISABLE __SCX_RESCUE_DISABLE
+
 const volatile u64 __SCX_RQ_ONLINE __weak;
 #define SCX_RQ_ONLINE __SCX_RQ_ONLINE
 
diff --git a/tools/sched_ext/include/scx/enums.autogen.h b/tools/sched_ext/include/scx/enums.autogen.h
index 7ec2e5e41cb2..c4a7260f0983 100644
--- a/tools/sched_ext/include/scx/enums.autogen.h
+++ b/tools/sched_ext/include/scx/enums.autogen.h
@@ -9,6 +9,7 @@
 	SCX_ENUM_SET(skel, scx_public_consts, SCX_OPS_NAME_LEN); \
 	SCX_ENUM_SET(skel, scx_public_consts, SCX_SLICE_DFL); \
 	SCX_ENUM_SET(skel, scx_public_consts, SCX_SLICE_INF); \
+	SCX_ENUM_SET(skel, scx_consts, SCX_RESCUE_DISABLE); \
 	SCX_ENUM_SET(skel, scx_rq_flags, SCX_RQ_ONLINE); \
 	SCX_ENUM_SET(skel, scx_rq_flags, SCX_RQ_CAN_STOP_TICK); \
 	SCX_ENUM_SET(skel, scx_rq_flags, SCX_RQ_BAL_PENDING); \
diff --git a/tools/sched_ext/scx_qmap.c b/tools/sched_ext/scx_qmap.c
index 9b1cbe187ebd..fe2f206f5c8a 100644
--- a/tools/sched_ext/scx_qmap.c
+++ b/tools/sched_ext/scx_qmap.c
@@ -427,7 +427,7 @@ int main(int argc, char **argv)
 			u32 ppt = strtoul(optarg, NULL, 0);
 
 			if (!ppt)
-				ppt = __COMPAT_ENUM_OR_ZERO("scx_consts", "SCX_RESCUE_DISABLE");
+				ppt = skel->rodata->__SCX_RESCUE_DISABLE;
 			skel->struct_ops.qmap_ops->rescue_bandwidth_ppt = ppt;
 			break;
 		}
-- 
2.56.0