On 8 September 2016 at 04:57, Fenghua Yu <fenghua...@intel.com> wrote:
> diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
> index fcd0642..b25940a 100644
> --- a/arch/x86/kernel/cpu/intel_rdt.c
> +++ b/arch/x86/kernel/cpu/intel_rdt.c
> @@ -21,17 +21,94 @@
> */
> #include <linux/slab.h>
> #include <linux/err.h>
> +#include <asm/intel_rdt.h>
> +
> +/*
> + * cctable maintains 1:1 mapping between CLOSid and cache bitmask.
> + */
> +static struct clos_cbm_table *cctable;
> +/*
> + * closid availability bit map.
> + */
> +unsigned long *closmap;
> +static DEFINE_MUTEX(rdtgroup_mutex);
> +
> +static inline void closid_get(u32 closid)
> +{
> + struct clos_cbm_table *cct = &cctable[closid];
> +
> + lockdep_assert_held(&rdtgroup_mutex);
> +
> + cct->clos_refcnt++;
> +}
> +
> +static int closid_alloc(u32 *closid)
> +{
> + u32 maxid;
> + u32 id;
> +
> + lockdep_assert_held(&rdtgroup_mutex);
> +
> + maxid = boot_cpu_data.x86_cache_max_closid;
> + id = find_first_zero_bit(closmap, maxid);
> + if (id == maxid)
> + return -ENOSPC;
> +
> + set_bit(id, closmap);
> + closid_get(id);
> + *closid = id;
> +
> + return 0;
> +}
> +
> +static inline void closid_free(u32 closid)
> +{
> + clear_bit(closid, closmap);
> + cctable[closid].cbm = 0;
> +}
> +
> +static void closid_put(u32 closid)
> +{
> + struct clos_cbm_table *cct = &cctable[closid];
> +
> + lockdep_assert_held(&rdtgroup_mutex);
> + if (WARN_ON(!cct->clos_refcnt))
> + return;
> +
> + if (!--cct->clos_refcnt)
> + closid_free(closid);
> +}
>
I would suggest a small change in the function names here. I think
the names closid_free and closid_put should be swapped. As I
understand, under the current naming scheme, the opposite of
closid_alloc() is closid_put() and the opposite of closid_get() is
closid_free(). This is not the normal way these names are paired.
Typically, alloc and free go as a pair and get and put go as a pair.
--
Nilay
