[Crash-utility] Re: [RFC PATCH 1/2] add cpu_to_nid function

Add cpu_to_nid function which we can use to get the NUMA node id by the cpu id. Signed-off-by: Huang Shijie <huangsj(a)hygon.cn&gt; --- defs.h | 2 ++ kernel.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ main.c | 1 + 3 files changed, 49 insertions(+) diff --git a/defs.h b/defs.h index a4f70b7..98a149b 100644 --- a/defs.h +++ b/defs.h @@ -6040,6 +6040,8 @@ ulong do_maple_tree(ulong, int, struct list_pair *); void help_init(void); void cmd_usage(char *, int); void display_version(void); +int cpu_to_nid(int cpu); +void numa_init(void); void display_help_screen(char *); #ifdef ARM #define dump_machdep_table(X) arm_dump_machdep_table(X) diff --git a/kernel.c b/kernel.c index eb9754c..15254a4 100644 --- a/kernel.c +++ b/kernel.c @@ -12207,3 +12207,49 @@ out: pc->error_fp = error_fp_save; } #endif + +static int *cpu_to_nid_map; + +int +cpu_to_nid(int cpu) +{ + if (!cpu_to_nid_map || cpu < 0 || cpu >= kt->cpus) + return -1; + if (vt->numnodes == 1) + return 0; + return cpu_to_nid_map[cpu]; +} + +static void +cpu_to_nid_init(void) +{ + int i, j; + int fd; + char buf[64]; + + cpu_to_nid_map = malloc(kt->cpus * sizeof(int)); + if (vt->numnodes == 1) + return; + + memset(cpu_to_nid_map, -1, kt->cpus * sizeof(int)); + + for (i = 0; i < kt->cpus; i++) { + for (j = 0; j < vt->numnodes; j++) { + memset(buf, 0, sizeof(buf)); + sprintf(buf, "/sys/devices/system/cpu/cpu%d/node%d", i, j);

+ + fd = open(buf, O_RDONLY); + if (fd > 0) { + cpu_to_nid_map[i] = j; + close(fd); + break; + } + } + } +} + +void +numa_init(void) +{ + cpu_to_nid_init(); +} diff --git a/main.c b/main.c index d5f8486..a8c77f8 100644 --- a/main.c +++ b/main.c @@ -793,6 +793,7 @@ main_loop(void) kernel_init(); machdep_init(POST_GDB); vm_init(); + numa_init(); machdep_init(POST_VM); module_init(); help_init(); -- 2.53.0