[MIPS] Fix deadlock on MP with cache aliases.

A proper fix would involve introducing the notion of shared caches but
at this stage of 2.6.17 that's going to be too intrusive and not needed
for current hardware; aside I think some discussion will be needed.

So for now on the affected SMP configurations which happen to suffer from
cache aliases we make use of the fact that a single cache will be shared
by all processors.  This solves the deadlock issue and will improve
performance by getting rid of the smp_call_function overhead.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Ralf Baechle 2006-05-12 13:20:06 +01:00
parent 78665aaa96
commit 7f3f1d01a9
1 changed files with 30 additions and 9 deletions

View File

@ -29,6 +29,27 @@
#include <asm/war.h>
#include <asm/cacheflush.h> /* for run_uncached() */
/*
* Special Variant of smp_call_function for use by cache functions:
*
* o No return value
* o collapses to normal function call on UP kernels
* o collapses to normal function call on systems with a single shared
* primary cache.
*/
static inline void r4k_on_each_cpu(void (*func) (void *info), void *info,
int retry, int wait)
{
preempt_disable();
#if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
smp_call_function(func, info, retry, wait);
#endif
func(info);
preempt_enable();
}
/*
* Must die.
*/
@ -299,7 +320,7 @@ static void r4k_flush_cache_all(void)
if (!cpu_has_dc_aliases)
return;
on_each_cpu(local_r4k_flush_cache_all, NULL, 1, 1);
r4k_on_each_cpu(local_r4k_flush_cache_all, NULL, 1, 1);
}
static inline void local_r4k___flush_cache_all(void * args)
@ -320,7 +341,7 @@ static inline void local_r4k___flush_cache_all(void * args)
static void r4k___flush_cache_all(void)
{
on_each_cpu(local_r4k___flush_cache_all, NULL, 1, 1);
r4k_on_each_cpu(local_r4k___flush_cache_all, NULL, 1, 1);
}
static inline void local_r4k_flush_cache_range(void * args)
@ -341,7 +362,7 @@ static inline void local_r4k_flush_cache_range(void * args)
static void r4k_flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
on_each_cpu(local_r4k_flush_cache_range, vma, 1, 1);
r4k_on_each_cpu(local_r4k_flush_cache_range, vma, 1, 1);
}
static inline void local_r4k_flush_cache_mm(void * args)
@ -370,7 +391,7 @@ static void r4k_flush_cache_mm(struct mm_struct *mm)
if (!cpu_has_dc_aliases)
return;
on_each_cpu(local_r4k_flush_cache_mm, mm, 1, 1);
r4k_on_each_cpu(local_r4k_flush_cache_mm, mm, 1, 1);
}
struct flush_cache_page_args {
@ -461,7 +482,7 @@ static void r4k_flush_cache_page(struct vm_area_struct *vma,
args.addr = addr;
args.pfn = pfn;
on_each_cpu(local_r4k_flush_cache_page, &args, 1, 1);
r4k_on_each_cpu(local_r4k_flush_cache_page, &args, 1, 1);
}
static inline void local_r4k_flush_data_cache_page(void * addr)
@ -471,7 +492,7 @@ static inline void local_r4k_flush_data_cache_page(void * addr)
static void r4k_flush_data_cache_page(unsigned long addr)
{
on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr, 1, 1);
r4k_on_each_cpu(local_r4k_flush_data_cache_page, (void *) addr, 1, 1);
}
struct flush_icache_range_args {
@ -514,7 +535,7 @@ static void r4k_flush_icache_range(unsigned long start, unsigned long end)
args.start = start;
args.end = end;
on_each_cpu(local_r4k_flush_icache_range, &args, 1, 1);
r4k_on_each_cpu(local_r4k_flush_icache_range, &args, 1, 1);
instruction_hazard();
}
@ -590,7 +611,7 @@ static void r4k_flush_icache_page(struct vm_area_struct *vma,
args.vma = vma;
args.page = page;
on_each_cpu(local_r4k_flush_icache_page, &args, 1, 1);
r4k_on_each_cpu(local_r4k_flush_icache_page, &args, 1, 1);
}
@ -689,7 +710,7 @@ static void local_r4k_flush_cache_sigtramp(void * arg)
static void r4k_flush_cache_sigtramp(unsigned long addr)
{
on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr, 1, 1);
r4k_on_each_cpu(local_r4k_flush_cache_sigtramp, (void *) addr, 1, 1);
}
static void r4k_flush_icache_all(void)