diff options
| author | Christian Cunningham <cc@localhost> | 2022-03-25 23:59:05 -0700 |
|---|---|---|
| committer | Christian Cunningham <cc@localhost> | 2022-03-25 23:59:05 -0700 |
| commit | 32ef93110fc993f24540bdcff6c3d88c47cd64c1 (patch) | |
| tree | 0ac9b4fa0258b0f3c9f2506b5f42a19fffa0629e /kernel/exceptions | |
| parent | e733d37ee2aee3a5f3850ab336d588f814bb134c (diff) | |
Don't schedule if you don't have to
Diffstat (limited to 'kernel/exceptions')
| -rw-r--r-- | kernel/exceptions/svc.S | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/kernel/exceptions/svc.S b/kernel/exceptions/svc.S index 75a0cf1..452831a 100644 --- a/kernel/exceptions/svc.S +++ b/kernel/exceptions/svc.S @@ -72,9 +72,11 @@ svc_000005: // Release Lock sev // Awake any threads waiting for this lock bl sched_mutex_resurrect + cmp r0, #0 + beq 1f ldmfd sp!, {r0-r12,lr} b schedule - b svc_exit +1: b svc_exit svc_000006: // Semaphore decrease ldr r0, [sp, #0] // struct Semaphore* s 1: clrex @@ -106,9 +108,11 @@ svc_000007: // Semaphore increase bne svc_exit mov r1, #1 bl sched_semaphore_resurrect + cmp r0, #0 + beq 1f ldmfd sp!, {r0-r12,lr} b schedule - b svc_exit +1: b svc_exit svc_000008: // Semaphore add # ldr r0, [sp, #0] // struct Semaphore* s ldr r3, [sp, #1] // unsigned long # times to increase @@ -121,9 +125,11 @@ svc_000008: // Semaphore add # dmb mov r1, r3 bl sched_semaphore_resurrect + cmp r0, #0 + beq 1f ldmfd sp!, {r0-r12,lr} b schedule - b svc_exit +1: b svc_exit svc_000009: // SYS_TIME_2 mrc p15, 0, r0, c9, c13, 0 str r0, [sp, #0] |