Re: [Crash-utility] [PATCH] Fix for "bpf -m|-M" options to appropriately display MEMLOCK and UID

Kernel commit <80ee81e0403c> ("bpf: Eliminate rlimit-based memory accounting infra for bpf maps") removed the struct bpf_map_memory member from struct bpf_map. Without the patch, "bpf -m|-M" options will print the following errors: crash> bpf -m 1 ID BPF_MAP BPF_MAP_TYPE MAP_FLAGS 1 ffff96ba41804400 ARRAY 00000000 KEY_SIZE: 4 VALUE_SIZE: 8 MAX_ENTRIES: 64 MEMLOCK: (unknown) ^^^^^^^ NAME: "dist" UID: (unknown) ^^^^^^^ Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com&gt; --- bpf.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 64 insertions(+), 3 deletions(-) diff --git a/bpf.c b/bpf.c index cb6b0ed385f9..d45e9ab9311b 100644 --- a/bpf.c +++ b/bpf.c @@ -15,6 +15,7 @@ */ #include "defs.h" +#include <stdbool.h> struct bpf_info { ulong status; @@ -63,6 +64,66 @@ static int do_old_idr(int, ulong, struct list_pair *); #define PROG_VERBOSE (0x40) #define MAP_VERBOSE (0x80) +static bool map_is_per_cpu(ulong type)

+{ + /* + * See the definition of bpf_map_type: + * include/uapi/linux/bpf.h + */ + #define BPF_MAP_TYPE_PERCPU_HASH (5UL) + #define BPF_MAP_TYPE_PERCPU_ARRAY (6UL) + #define BPF_MAP_TYPE_LRU_PERCPU_HASH (10UL) + #define BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE (21UL)

+ + return type == BPF_MAP_TYPE_PERCPU_HASH || + type == BPF_MAP_TYPE_PERCPU_ARRAY || + type == BPF_MAP_TYPE_LRU_PERCPU_HASH || + type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE; +} + +static bool map_is_fd_map(ulong type) +{ + /* + * See the definition of bpf_map_type: + * include/uapi/linux/bpf.h + */ + #define BPF_MAP_TYPE_PROG_ARRAY (3UL) + #define BPF_MAP_TYPE_PERF_EVENT_ARRAY (4UL) + #define BPF_MAP_TYPE_CGROUP_ARRAY (8UL) + #define BPF_MAP_TYPE_ARRAY_OF_MAPS (12UL) + #define BPF_MAP_TYPE_HASH_OF_MAPS (13UL)

+ + return type == BPF_MAP_TYPE_PROG_ARRAY || + type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || + type == BPF_MAP_TYPE_CGROUP_ARRAY || + type == BPF_MAP_TYPE_ARRAY_OF_MAPS || + type == BPF_MAP_TYPE_HASH_OF_MAPS; + +} + +static ulong bpf_map_memory_size(ulong map_type, ulong vsize, ulong ksize, ulong esize)

+{ + ulong memsize,valsize; + int cpus = 0; + + valsize = vsize; + + if (map_is_fd_map(map_type)) + valsize = sizeof(ulong);

+ + if (map_is_per_cpu(map_type)) { + cpus = get_cpus_possible(); + if (!cpus) + error(WARNING, "cpu_possible_map does not exist, pissible cpus: %d\n", cpus);

+ + valsize = roundup(vsize, 8) * cpus; + } + + memsize = roundup((ksize + valsize), 8); + + return roundup((esize * memsize), PAGESIZE()); +} + void cmd_bpf(void) { @@ -332,7 +393,7 @@ do_bpf(ulong flags, ulong prog_id, ulong map_id, int radix) { struct bpf_info *bpf; int i, c, found, entries, type; - uint uid, map_pages, key_size, value_size, max_entries; + uint uid, map_pages, key_size = 0, value_size = 0, max_entries = 0; ulong bpf_prog_aux, bpf_func, end_func, addr, insnsi, user; ulong do_progs, do_maps; ulonglong load_time; @@ -603,7 +664,7 @@ do_map_only: map_pages = UINT(bpf->bpf_map_buf + OFFSET(bpf_map_pages)); fprintf(fp, "%d\n", map_pages * PAGESIZE()); } else - fprintf(fp, "(unknown)\n"); + fprintf(fp, "%ld\n", bpf_map_memory_size(type, value_size, key_size, max_entries));

fprintf(fp, " NAME: "); if (VALID_MEMBER(bpf_map_name)) { @@ -632,7 +693,7 @@ do_map_only: else fprintf(fp, "(unknown)\n"); } else - fprintf(fp, "(unknown)\n"); + fprintf(fp, "(unused)\n"); } if (flags & DUMP_STRUCT) { -- 2.20.1