From 777537905744c28b02c283692e7f75f5445c1afa Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Tue, 12 Jan 2010 09:55:10 +0100 Subject: microblaze: Add support from PREEMPT This patch add core PREEMPT support for Microblaze. I tried to trace it via tracers and I was able to see any output. I also added low level debug functions to see if that code is called. Signed-off-by: Michal Simek --- arch/microblaze/kernel/asm-offsets.c | 1 + arch/microblaze/kernel/entry.S | 25 ++++++++++++++++++++++++- 2 files changed, 25 insertions(+), 1 deletion(-) (limited to 'arch/microblaze/kernel') diff --git a/arch/microblaze/kernel/asm-offsets.c b/arch/microblaze/kernel/asm-offsets.c index 7bc7b68f97db..0071260a672c 100644 --- a/arch/microblaze/kernel/asm-offsets.c +++ b/arch/microblaze/kernel/asm-offsets.c @@ -90,6 +90,7 @@ int main(int argc, char *argv[]) DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit)); DEFINE(TI_CPU_CONTEXT, offsetof(struct thread_info, cpu_context)); + DEFINE(TI_PREEMPT_COUNT, offsetof(struct thread_info, preempt_count)); BLANK(); /* struct cpu_context */ diff --git a/arch/microblaze/kernel/entry.S b/arch/microblaze/kernel/entry.S index 3bad4ff49471..1a6729dde49e 100644 --- a/arch/microblaze/kernel/entry.S +++ b/arch/microblaze/kernel/entry.S @@ -853,7 +853,30 @@ no_intr_resched: lwi r1, r1, PT_R1 - PT_SIZE; bri 6f; /* MS: Return to kernel state. */ -2: VM_OFF /* MS: turn off MMU */ +2: +#ifdef CONFIG_PREEMPT + add r11, r0, CURRENT_TASK; + lwi r11, r11, TS_THREAD_INFO; + /* MS: get preempt_count from thread info */ + lwi r5, r11, TI_PREEMPT_COUNT; + bgti r5, restore; + + lwi r5, r11, TI_FLAGS; /* get flags in thread info */ + andi r5, r5, _TIF_NEED_RESCHED; + beqi r5, restore /* if zero jump over */ + +preempt: + /* interrupts are off that's why I am calling preempt_chedule_irq */ + bralid r15, preempt_schedule_irq + nop + add r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */ + lwi r11, r11, TS_THREAD_INFO; /* get thread info */ + lwi r5, r11, TI_FLAGS; /* get flags in thread info */ + andi r5, r5, _TIF_NEED_RESCHED; + bnei r5, preempt /* if non zero jump to resched */ +restore: +#endif + VM_OFF /* MS: turn off MMU */ tophys(r1,r1) lwi r3, r1, PTO + PT_R3; /* MS: restore saved r3, r4 registers */ lwi r4, r1, PTO + PT_R4; -- cgit v1.2.2