Re: [PATCH v8 04/16] sched/core: uclamp: Add system default clamps
From: Peter Zijlstra <peterz@infradead.org>
Date: 2019-05-08 19:07:46
Also in:
linux-pm, lkml
From: Peter Zijlstra <peterz@infradead.org>
Date: 2019-05-08 19:07:46
Also in:
linux-pm, lkml
On Tue, Apr 02, 2019 at 11:41:40AM +0100, Patrick Bellasi wrote:
+static inline struct uclamp_se
+uclamp_eff_get(struct task_struct *p, unsigned int clamp_id)
+{
+ struct uclamp_se uc_req = p->uclamp_req[clamp_id];
+ struct uclamp_se uc_max = uclamp_default[clamp_id];
+
+ /* System default restrictions always apply */
+ if (unlikely(uc_req.value > uc_max.value))
+ return uc_max;
+
+ return uc_req;
+}
+
+static inline unsigned int
+uclamp_eff_bucket_id(struct task_struct *p, unsigned int clamp_id)
+{
+ struct uclamp_se uc_eff;
+
+ /* Task currently refcounted: use back-annotated (effective) bucket */
+ if (p->uclamp[clamp_id].active)
+ return p->uclamp[clamp_id].bucket_id;
+
+ uc_eff = uclamp_eff_get(p, clamp_id);
+
+ return uc_eff.bucket_id;
+}
+
+unsigned int uclamp_eff_value(struct task_struct *p, unsigned int clamp_id)
+{
+ struct uclamp_se uc_eff;
+
+ /* Task currently refcounted: use back-annotated (effective) value */
+ if (p->uclamp[clamp_id].active)
+ return p->uclamp[clamp_id].value;
+
+ uc_eff = uclamp_eff_get(p, clamp_id);
+
+ return uc_eff.value;
+}This is 'wrong' because: uclamp_eff_value(p,id) := uclamp_eff(p,id).value Which seems to suggest the uclamp_eff_*() functions want another name. Also, suppose the above would be true; does GCC really generate better code for the LHS compared to the RHS?