[Crash-utility] [PATCH v2] 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, the "bpf -m|-M" options
will print "(unknown)" for MEMLOCK and UID:
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>
Signed-off-by: Kazuhito Hagio <k-hagio-ab(a)nec.com>
---
bpf.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 66 insertions(+), 4 deletions(-)
diff --git a/bpf.c b/bpf.c
index cb6b0ed385f9..466b244e0c3a 100644
--- a/bpf.c
+++ b/bpf.c
@@ -63,6 +63,64 @@ static int do_old_idr(int, ulong, struct list_pair *);
#define PROG_VERBOSE (0x40)
#define MAP_VERBOSE (0x80)
+static int map_is_per_cpu(int 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 int map_is_fd_map(int 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(int map_type, uint value_size,
+ uint key_size, uint max_entries)
+{
+ ulong size;
+ uint valsize;
+ int cpus = 0;
+
+ if (map_is_per_cpu(map_type)) {
+ cpus = get_cpus_possible();
+ if (!cpus) {
+ error(WARNING, "cpu_possible_map does not exist, possible cpus: %d\n",
cpus);
+ return 0;
+ }
+
+ valsize = roundup(value_size, 8) * cpus;
+ } else if (map_is_fd_map(map_type))
+ valsize = sizeof(uint);
+ else
+ valsize = value_size;
+
+ size = roundup((key_size + valsize), 8);
+
+ return roundup((max_entries * size), PAGESIZE());
+}
+
void
cmd_bpf(void)
{
@@ -332,7 +390,7 @@ 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;
@@ -572,6 +630,8 @@ do_map_only:
fprintf(fp, "\n");
if (flags & (MAP_ID|MAP_VERBOSE)) {
+ ulong msize = 0;
+
fprintf(fp, " KEY_SIZE: ");
if (VALID_MEMBER(bpf_map_key_size)) {
key_size = UINT(bpf->bpf_map_buf + OFFSET(bpf_map_key_size));
@@ -602,8 +662,10 @@ do_map_only:
} else if (VALID_MEMBER(bpf_map_pages)) {
map_pages = UINT(bpf->bpf_map_buf + OFFSET(bpf_map_pages));
fprintf(fp, "%d\n", map_pages * PAGESIZE());
- } else
- fprintf(fp, "(unknown)\n");
+ } else if ((msize = bpf_map_memory_size(type, value_size, key_size, max_entries)))
+ fprintf(fp, "%ld\n", msize);
+ else
+ fprintf(fp, "(unknown)");
fprintf(fp, " NAME: ");
if (VALID_MEMBER(bpf_map_name)) {
@@ -632,7 +694,7 @@ do_map_only:
else
fprintf(fp, "(unknown)\n");
} else
- fprintf(fp, "(unknown)\n");
+ fprintf(fp, "(unused)\n");
}
if (flags & DUMP_STRUCT) {
--
2.30.2