[tip: sched/core] psi: Pressure states are unlikely

2021-03-06 Thread tip-bot2 for Johannes Weiner 
The following commit has been merged into the sched/core branch of tip:

Commit-ID: fddc8bab531e217806b84906681324377d741c6c
Gitweb:
https://git.kernel.org/tip/fddc8bab531e217806b84906681324377d741c6c
Author:Johannes Weiner 
AuthorDate:Wed, 03 Mar 2021 11:46:58 +08:00
Committer: Ingo Molnar 
CommitterDate: Sat, 06 Mar 2021 12:40:23 +01:00

psi: Pressure states are unlikely

Move the unlikely branches out of line. This eliminates undesirable
jumps during wakeup and sleeps for workloads that aren't under any
sort of resource pressure.

Signed-off-by: Johannes Weiner 
Signed-off-by: Chengming Zhou 
Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Ingo Molnar 
Link: 
https://lkml.kernel.org/r/20210303034659.91735-4-zhouchengm...@bytedance.com
---
 kernel/sched/psi.c | 14 +++---
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 0fe6ff6..3907a6b 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -219,17 +219,17 @@ static bool test_state(unsigned int *tasks, enum 
psi_states state)
 {
switch (state) {
case PSI_IO_SOME:
-   return tasks[NR_IOWAIT];
+   return unlikely(tasks[NR_IOWAIT]);
case PSI_IO_FULL:
-   return tasks[NR_IOWAIT] && !tasks[NR_RUNNING];
+   return unlikely(tasks[NR_IOWAIT] && !tasks[NR_RUNNING]);
case PSI_MEM_SOME:
-   return tasks[NR_MEMSTALL];
+   return unlikely(tasks[NR_MEMSTALL]);
case PSI_MEM_FULL:
-   return tasks[NR_MEMSTALL] && !tasks[NR_RUNNING];
+   return unlikely(tasks[NR_MEMSTALL] && !tasks[NR_RUNNING]);
case PSI_CPU_SOME:
-   return tasks[NR_RUNNING] > tasks[NR_ONCPU];
+   return unlikely(tasks[NR_RUNNING] > tasks[NR_ONCPU]);
case PSI_CPU_FULL:
-   return tasks[NR_RUNNING] && !tasks[NR_ONCPU];
+   return unlikely(tasks[NR_RUNNING] && !tasks[NR_ONCPU]);
case PSI_NONIDLE:
return tasks[NR_IOWAIT] || tasks[NR_MEMSTALL] ||
tasks[NR_RUNNING];
@@ -729,7 +729,7 @@ static void psi_group_change(struct psi_group *group, int 
cpu,
 * task in a cgroup is in_memstall, the corresponding groupc
 * on that cpu is in PSI_MEM_FULL state.
 */
-   if (groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall)
+   if (unlikely(groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall))
state_mask |= (1 << PSI_MEM_FULL);
 
groupc->state_mask = state_mask;

[tip: sched/core] psi: Pressure states are unlikely

2021-03-04 Thread tip-bot2 for Johannes Weiner 
The following commit has been merged into the sched/core branch of tip:

Commit-ID: 24f3cb558f59debe0e9159459bb9627b51b47c17
Gitweb:
https://git.kernel.org/tip/24f3cb558f59debe0e9159459bb9627b51b47c17
Author:Johannes Weiner 
AuthorDate:Wed, 03 Mar 2021 11:46:58 +08:00
Committer: Peter Zijlstra 
CommitterDate: Thu, 04 Mar 2021 09:56:02 +01:00

psi: Pressure states are unlikely

Move the unlikely branches out of line. This eliminates undesirable
jumps during wakeup and sleeps for workloads that aren't under any
sort of resource pressure.

Signed-off-by: Johannes Weiner 
Signed-off-by: Chengming Zhou 
Signed-off-by: Peter Zijlstra (Intel) 
Link: 
https://lkml.kernel.org/r/20210303034659.91735-4-zhouchengm...@bytedance.com
---
 kernel/sched/psi.c | 14 +++---
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 0fe6ff6..3907a6b 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -219,17 +219,17 @@ static bool test_state(unsigned int *tasks, enum 
psi_states state)
 {
switch (state) {
case PSI_IO_SOME:
-   return tasks[NR_IOWAIT];
+   return unlikely(tasks[NR_IOWAIT]);
case PSI_IO_FULL:
-   return tasks[NR_IOWAIT] && !tasks[NR_RUNNING];
+   return unlikely(tasks[NR_IOWAIT] && !tasks[NR_RUNNING]);
case PSI_MEM_SOME:
-   return tasks[NR_MEMSTALL];
+   return unlikely(tasks[NR_MEMSTALL]);
case PSI_MEM_FULL:
-   return tasks[NR_MEMSTALL] && !tasks[NR_RUNNING];
+   return unlikely(tasks[NR_MEMSTALL] && !tasks[NR_RUNNING]);
case PSI_CPU_SOME:
-   return tasks[NR_RUNNING] > tasks[NR_ONCPU];
+   return unlikely(tasks[NR_RUNNING] > tasks[NR_ONCPU]);
case PSI_CPU_FULL:
-   return tasks[NR_RUNNING] && !tasks[NR_ONCPU];
+   return unlikely(tasks[NR_RUNNING] && !tasks[NR_ONCPU]);
case PSI_NONIDLE:
return tasks[NR_IOWAIT] || tasks[NR_MEMSTALL] ||
tasks[NR_RUNNING];
@@ -729,7 +729,7 @@ static void psi_group_change(struct psi_group *group, int 
cpu,
 * task in a cgroup is in_memstall, the corresponding groupc
 * on that cpu is in PSI_MEM_FULL state.
 */
-   if (groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall)
+   if (unlikely(groupc->tasks[NR_ONCPU] && cpu_curr(cpu)->in_memstall))
state_mask |= (1 << PSI_MEM_FULL);
 
groupc->state_mask = state_mask;