diff options
Diffstat (limited to 'arch/arc/kernel/ctx_sw.c')
| -rw-r--r-- | arch/arc/kernel/ctx_sw.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/arch/arc/kernel/ctx_sw.c b/arch/arc/kernel/ctx_sw.c index 60844dac613..c14a5bea0c7 100644 --- a/arch/arc/kernel/ctx_sw.c +++ b/arch/arc/kernel/ctx_sw.c @@ -17,16 +17,14 @@ #include <asm/asm-offsets.h> #include <linux/sched.h> +#define KSP_WORD_OFF ((TASK_THREAD + THREAD_KSP) / 4) + struct task_struct *__sched __switch_to(struct task_struct *prev_task, struct task_struct *next_task) { unsigned int tmp; unsigned int prev = (unsigned int)prev_task; unsigned int next = (unsigned int)next_task; - int num_words_to_skip = 1; -#ifdef CONFIG_ARC_CURR_IN_REG - num_words_to_skip++; -#endif __asm__ __volatile__( /* FP/BLINK save generated by gcc (standard function prologue */ @@ -44,11 +42,21 @@ __switch_to(struct task_struct *prev_task, struct task_struct *next_task) "st.a r24, [sp, -4] \n\t" #ifndef CONFIG_ARC_CURR_IN_REG "st.a r25, [sp, -4] \n\t" +#else + "sub sp, sp, 4 \n\t" /* usual r25 placeholder */ #endif - "sub sp, sp, %4 \n\t" /* create gutter at top */ /* set ksp of outgoing task in tsk->thread.ksp */ +#if KSP_WORD_OFF <= 255 "st.as sp, [%3, %1] \n\t" +#else + /* + * Workaround for NR_CPUS=4k + * %1 is bigger than 255 (S9 offset for st.as) + */ + "add2 r24, %3, %1 \n\t" + "st sp, [r24] \n\t" +#endif "sync \n\t" @@ -76,10 +84,10 @@ __switch_to(struct task_struct *prev_task, struct task_struct *next_task) /* start loading it's CALLEE reg file */ - "add sp, sp, %4 \n\t" /* skip gutter at top */ - #ifndef CONFIG_ARC_CURR_IN_REG "ld.ab r25, [sp, 4] \n\t" +#else + "add sp, sp, 4 \n\t" #endif "ld.ab r24, [sp, 4] \n\t" "ld.ab r23, [sp, 4] \n\t" @@ -100,8 +108,7 @@ __switch_to(struct task_struct *prev_task, struct task_struct *next_task) /* FP/BLINK restore generated by gcc (standard func epilogue */ : "=r"(tmp) - : "n"((TASK_THREAD + THREAD_KSP) / 4), "r"(next), "r"(prev), - "n"(num_words_to_skip * 4) + : "n"(KSP_WORD_OFF), "r"(next), "r"(prev) : "blink" ); |