UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

ARM: bL_switcher: Add query interface to discover CPU affinities 

When the switcher is active, there is no straightforward way to
figure out which logical CPU a given physical CPU maps to.

This patch provides a function
bL_switcher_get_logical_index(mpidr), which is analogous to
get_logical_index().

This function returns the logical CPU on which the specified
physical CPU is grouped (or -EINVAL if unknown).
If the switcher is inactive or not present, -EUNATCH is returned instead.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
This commit is contained in:
Dave Martin 2013-02-13 16:20:44 +00:00 committed by Nicolas Pitre
parent 29064b8846
commit d08e2e0904
2 changed files with 22 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/arm/common/bL_switcher.c
View File

@ -532,6 +532,26 @@ static int bL_switcher_halve_cpus(void)
return 0;
}
/* Determine the logical CPU a given physical CPU is grouped on. */
int bL_switcher_get_logical_index(u32 mpidr)
{
int cpu;
if (!bL_switcher_active)
return -EUNATCH;
mpidr &= MPIDR_HWID_BITMASK;
for_each_online_cpu(cpu) {
int pairing = bL_switcher_cpu_pairing[cpu];
if (pairing == -1)
continue;
if ((mpidr == cpu_logical_map(cpu)) ||
(mpidr == cpu_logical_map(pairing)))
return cpu;
}
return -EINVAL;
}
static void bL_switcher_trace_trigger_cpu(void *__always_unused info)
{
trace_cpu_migrate_current(get_ns(), read_mpidr());

2
arch/arm/include/asm/bL_switcher.h
View File

@ -55,6 +55,7 @@ bool bL_switcher_get_enabled(void);
void bL_switcher_put_enabled(void);
int bL_switcher_trace_trigger(void);
int bL_switcher_get_logical_index(u32 mpidr);
#else
static inline int bL_switcher_register_notifier(struct notifier_block *nb)
@ -70,6 +71,7 @@ static inline int bL_switcher_unregister_notifier(struct notifier_block *nb)
static inline bool bL_switcher_get_enabled(void) { return false; }
static inline void bL_switcher_put_enabled(void) { }
static inline int bL_switcher_trace_trigger(void) { return 0; }
static inline int bL_switcher_get_logical_index(u32 mpidr) { return -EUNATCH; }
#endif /* CONFIG_BL_SWITCHER */
#endif