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Diffstat (limited to 'Documentation/cputopology.txt')
| -rw-r--r-- | Documentation/cputopology.txt | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt index 12b1b25b4da9..f722f227a73b 100644 --- a/Documentation/cputopology.txt +++ b/Documentation/cputopology.txt @@ -20,48 +20,70 @@ to /proc/cpuinfo output of some architectures: identifier (rather than the kernel's). The actual value is architecture and platform dependent. -4) /sys/devices/system/cpu/cpuX/topology/thread_siblings: +4) /sys/devices/system/cpu/cpuX/topology/drawer_id: + + the drawer ID of cpuX. Typically it is the hardware platform's + identifier (rather than the kernel's). The actual value is + architecture and platform dependent. + +5) /sys/devices/system/cpu/cpuX/topology/thread_siblings: internal kernel map of cpuX's hardware threads within the same core as cpuX. -5) /sys/devices/system/cpu/cpuX/topology/thread_siblings_list: +6) /sys/devices/system/cpu/cpuX/topology/thread_siblings_list: human-readable list of cpuX's hardware threads within the same core as cpuX. -6) /sys/devices/system/cpu/cpuX/topology/core_siblings: +7) /sys/devices/system/cpu/cpuX/topology/core_siblings: internal kernel map of cpuX's hardware threads within the same physical_package_id. -7) /sys/devices/system/cpu/cpuX/topology/core_siblings_list: +8) /sys/devices/system/cpu/cpuX/topology/core_siblings_list: human-readable list of cpuX's hardware threads within the same physical_package_id. -8) /sys/devices/system/cpu/cpuX/topology/book_siblings: +9) /sys/devices/system/cpu/cpuX/topology/book_siblings: internal kernel map of cpuX's hardware threads within the same book_id. -9) /sys/devices/system/cpu/cpuX/topology/book_siblings_list: +10) /sys/devices/system/cpu/cpuX/topology/book_siblings_list: human-readable list of cpuX's hardware threads within the same book_id. +11) /sys/devices/system/cpu/cpuX/topology/drawer_siblings: + + internal kernel map of cpuX's hardware threads within the same + drawer_id. + +12) /sys/devices/system/cpu/cpuX/topology/drawer_siblings_list: + + human-readable list of cpuX's hardware threads within the same + drawer_id. + To implement it in an architecture-neutral way, a new source file, -drivers/base/topology.c, is to export the 6 or 9 attributes. The three book -related sysfs files will only be created if CONFIG_SCHED_BOOK is selected. +drivers/base/topology.c, is to export the 6 to 12 attributes. The book +and drawer related sysfs files will only be created if CONFIG_SCHED_BOOK +and CONFIG_SCHED_DRAWER are selected. + +CONFIG_SCHED_BOOK and CONFIG_DRAWER are currently only used on s390, where +they reflect the cpu and cache hierarchy. For an architecture to support this feature, it must define some of these macros in include/asm-XXX/topology.h: #define topology_physical_package_id(cpu) #define topology_core_id(cpu) #define topology_book_id(cpu) +#define topology_drawer_id(cpu) #define topology_sibling_cpumask(cpu) #define topology_core_cpumask(cpu) #define topology_book_cpumask(cpu) +#define topology_drawer_cpumask(cpu) The type of **_id macros is int. The type of **_cpumask macros is (const) struct cpumask *. The latter @@ -78,6 +100,8 @@ not defined by include/asm-XXX/topology.h: For architectures that don't support books (CONFIG_SCHED_BOOK) there are no default definitions for topology_book_id() and topology_book_cpumask(). +For architectures that don't support drawes (CONFIG_SCHED_DRAWER) there are +no default definitions for topology_drawer_id() and topology_drawer_cpumask(). Additionally, CPU topology information is provided under /sys/devices/system/cpu and includes these files. The internal |