[PATCH net-next 5/9] samples/bpf: move ksym_search() into library

Alexei Starovoitov
2016-03-07T02:00:46Z

move ksym search from offwaketime into library to be reused
in other tests

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
samples/bpf/bpf_load.c | 62 ++++++++++++++++++++++++++++++++++++++
samples/bpf/bpf_load.h | 6 ++++
samples/bpf/offwaketime_user.c | 67 +-----------------------------------------
3 files changed, 69 insertions(+), 66 deletions(-)

diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index 816bca5760a0..d16864293c00 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -346,3 +346,65 @@ void read_trace_pipe(void)
}
}
}
+
+#define MAX_SYMS 300000
+static struct ksym syms[MAX_SYMS];
+static int sym_cnt;
+
+static int ksym_cmp(const void *p1, const void *p2)
+{
+ return ((struct ksym *)p1)->addr - ((struct ksym *)p2)->addr;
+}
+
+int load_kallsyms(void)
+{
+ FILE *f = fopen("/proc/kallsyms", "r");
+ char func[256], buf[256];
+ char symbol;
+ void *addr;
+ int i = 0;
+
+ if (!f)
+ return -ENOENT;
+
+ while (!feof(f)) {
+ if (!fgets(buf, sizeof(buf), f))
+ break;
+ if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
+ break;
+ if (!addr)
+ continue;
+ syms[i].addr = (long) addr;
+ syms[i].name = strdup(func);
+ i++;
+ }
+ sym_cnt = i;
+ qsort(syms, sym_cnt, sizeof(struct ksym), ksym_cmp);
+ return 0;
+}
+
+struct ksym *ksym_search(long key)
+{
+ int start = 0, end = sym_cnt;
+ int result;
+
+ while (start < end) {
+ size_t mid = start + (end - start) / 2;
+
+ result = key - syms[mid].addr;
+ if (result < 0)
+ end = mid;
+ else if (result > 0)
+ start = mid + 1;
+ else
+ return &syms[mid];
+ }
+
+ if (start >= 1 && syms[start - 1].addr < key &&
+ key < syms[start].addr)
+ /* valid ksym */
+ return &syms[start - 1];
+
+ /* out of range. return _stext */
+ return &syms[0];
+}
diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index cbd7c2b532b9..dfa57fe65c8e 100644
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -23,5 +23,11 @@ extern int event_fd[MAX_PROGS];
int load_bpf_file(char *path);

void read_trace_pipe(void);
+struct ksym {
+ long addr;
+ char *name;
+};

+int load_kallsyms(void);
+struct ksym *ksym_search(long key);
#endif
diff --git a/samples/bpf/offwaketime_user.c b/samples/bpf/offwaketime_user.c
index 17cf3024e22c..6f002a9c24fa 100644
--- a/samples/bpf/offwaketime_user.c
+++ b/samples/bpf/offwaketime_user.c
@@ -18,80 +18,15 @@
#include "libbpf.h"
#include "bpf_load.h"

-#define MAX_SYMS 300000
#define PRINT_RAW_ADDR 0

-static struct ksym {
- long addr;
- char *name;
-} syms[MAX_SYMS];
-static int sym_cnt;
-
-static int ksym_cmp(const void *p1, const void *p2)
-{
- return ((struct ksym *)p1)->addr - ((struct ksym *)p2)->addr;
-}
-
-static int load_kallsyms(void)
-{
- FILE *f = fopen("/proc/kallsyms", "r");
- char func[256], buf[256];
- char symbol;
- void *addr;
- int i = 0;
-
- if (!f)
- return -ENOENT;
-
- while (!feof(f)) {
- if (!fgets(buf, sizeof(buf), f))
- break;
- if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
- break;
- if (!addr)
- continue;
- syms[i].addr = (long) addr;
- syms[i].name = strdup(func);
- i++;
- }
- sym_cnt = i;
- qsort(syms, sym_cnt, sizeof(struct ksym), ksym_cmp);
- return 0;
-}
-
-static void *search(long key)
-{
- int start = 0, end = sym_cnt;
- int result;
-
- while (start < end) {
- size_t mid = start + (end - start) / 2;
-
- result = key - syms[mid].addr;
- if (result < 0)
- end = mid;
- else if (result > 0)
- start = mid + 1;
- else
- return &syms[mid];
- }
-
- if (start >= 1 && syms[start - 1].addr < key &&
- key < syms[start].addr)
- /* valid ksym */
- return &syms[start - 1];
-
- /* out of range. return _stext */
- return &syms[0];
-}
-
static void print_ksym(__u64 addr)
{
struct ksym *sym;

if (!addr)
return;
- sym = search(addr);
+ sym = ksym_search(addr);
if (PRINT_RAW_ADDR)
printf("%s/%llx;", sym->name, addr);
else
--
2.6.5