From 2328af0c9ce89d3ec121ba832c4e6faeff9e70ac Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Sun, 17 Feb 2013 12:51:42 +0200 Subject: [PATCH] ARC: [SMP] Enable icache coherency icaches are not snooped hence not cohrent in SMP setups which means kernel has to do cross core calls to ensure the same. The leaf routine __ic_line_inv_vaddr() now does cross core calls. __sync_icache_dcache() is affected due to this: * local dcache line flushed ahead of remote icache inv requests * can't disable interrupts anymore, since __ic_line_inv_vaddr()->on_each_cpu() can deadlock. | WARNING: CPU: 0 PID: 1 at kernel/smp.c:374 | smp_call_function_many+0x25a/0x2c4() | | init_kprobes+0x90/0xc8 | register_kprobe+0x1d6/0x510 | __sync_icache_dcache+0x28/0x80 | | DISABLE IRQ | | __ic_line_inv_vaddr | on_each_cpu | smp_call_function_many+0x25a/0x2c4 --> WARN | __ic_line_inv_vaddr_local | __dc_line_op * TODO: Needs to use mask of relevant CPUs to avoid broadcasting Signed-off-by: Noam Camus Signed-off-by: Vineet Gupta --- arch/arc/mm/cache_arc700.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/arch/arc/mm/cache_arc700.c b/arch/arc/mm/cache_arc700.c index 1f676c4..353b202 100644 --- a/arch/arc/mm/cache_arc700.c +++ b/arch/arc/mm/cache_arc700.c @@ -389,7 +389,7 @@ static inline void __dc_line_op(unsigned long paddr, unsigned long vaddr, /*********************************************************** * Machine specific helper for per line I-Cache invalidate. */ -static void __ic_line_inv_vaddr(unsigned long paddr, unsigned long vaddr, +static void __ic_line_inv_vaddr_local(unsigned long paddr, unsigned long vaddr, unsigned long sz) { unsigned long flags; @@ -405,6 +405,23 @@ static inline void __ic_entire_inv(void) read_aux_reg(ARC_REG_IC_CTRL); /* blocks */ } +struct ic_line_inv_vaddr_ipi { + unsigned long paddr, vaddr; + int sz; +}; + +static void __ic_line_inv_vaddr_helper(void *info) +{ + struct ic_line_inv_vaddr_ipi *ic_inv = (struct ic_line_inv_vaddr_ipi*) info; + __ic_line_inv_vaddr_local(ic_inv->paddr, ic_inv->vaddr, ic_inv->sz); +} + +static void __ic_line_inv_vaddr(unsigned long paddr, unsigned long vaddr, + unsigned long sz) +{ + struct ic_line_inv_vaddr_ipi ic_inv = { paddr, vaddr , sz}; + on_each_cpu(__ic_line_inv_vaddr_helper, &ic_inv, 1); +} #else #define __ic_entire_inv() @@ -553,12 +570,8 @@ void flush_icache_range(unsigned long kstart, unsigned long kend) */ void __sync_icache_dcache(unsigned long paddr, unsigned long vaddr, int len) { - unsigned long flags; - - local_irq_save(flags); - __ic_line_inv_vaddr(paddr, vaddr, len); __dc_line_op(paddr, vaddr, len, OP_FLUSH_N_INV); - local_irq_restore(flags); + __ic_line_inv_vaddr(paddr, vaddr, len); } /* wrapper to compile time eliminate alignment checks in flush loop */ -- 2.7.4