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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:35:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:39:31 +0000
commit85c675d0d09a45a135bddd15d7b385f8758c32fb (patch)
tree76267dbc9b9a130337be3640948fe397b04ac629 /tools/testing/selftests/bpf/trace_helpers.c
parentAdding upstream version 6.6.15. (diff)
downloadlinux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz
linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/trace_helpers.c')
-rw-r--r--tools/testing/selftests/bpf/trace_helpers.c134
1 files changed, 98 insertions, 36 deletions
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c
index f83d9f65c6..4faa898ff7 100644
--- a/tools/testing/selftests/bpf/trace_helpers.c
+++ b/tools/testing/selftests/bpf/trace_helpers.c
@@ -7,6 +7,7 @@
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
+#include <pthread.h>
#include <unistd.h>
#include <linux/perf_event.h>
#include <sys/mman.h>
@@ -14,104 +15,165 @@
#include <linux/limits.h>
#include <libelf.h>
#include <gelf.h>
+#include "bpf/libbpf_internal.h"
#define TRACEFS_PIPE "/sys/kernel/tracing/trace_pipe"
#define DEBUGFS_PIPE "/sys/kernel/debug/tracing/trace_pipe"
-#define MAX_SYMS 400000
-static struct ksym syms[MAX_SYMS];
-static int sym_cnt;
+struct ksyms {
+ struct ksym *syms;
+ size_t sym_cap;
+ size_t sym_cnt;
+};
+
+static struct ksyms *ksyms;
+static pthread_mutex_t ksyms_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static int ksyms__add_symbol(struct ksyms *ksyms, const char *name,
+ unsigned long addr)
+{
+ void *tmp;
+
+ tmp = strdup(name);
+ if (!tmp)
+ return -ENOMEM;
+ ksyms->syms[ksyms->sym_cnt].addr = addr;
+ ksyms->syms[ksyms->sym_cnt].name = tmp;
+ ksyms->sym_cnt++;
+ return 0;
+}
+
+void free_kallsyms_local(struct ksyms *ksyms)
+{
+ unsigned int i;
+
+ if (!ksyms)
+ return;
+
+ if (!ksyms->syms) {
+ free(ksyms);
+ return;
+ }
+
+ for (i = 0; i < ksyms->sym_cnt; i++)
+ free(ksyms->syms[i].name);
+ free(ksyms->syms);
+ free(ksyms);
+}
static int ksym_cmp(const void *p1, const void *p2)
{
return ((struct ksym *)p1)->addr - ((struct ksym *)p2)->addr;
}
-int load_kallsyms_refresh(void)
+struct ksyms *load_kallsyms_local(void)
{
FILE *f;
char func[256], buf[256];
char symbol;
void *addr;
- int i = 0;
-
- sym_cnt = 0;
+ int ret;
+ struct ksyms *ksyms;
f = fopen("/proc/kallsyms", "r");
if (!f)
- return -ENOENT;
+ return NULL;
+
+ ksyms = calloc(1, sizeof(struct ksyms));
+ if (!ksyms) {
+ fclose(f);
+ return NULL;
+ }
while (fgets(buf, sizeof(buf), f)) {
if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
break;
if (!addr)
continue;
- if (i >= MAX_SYMS)
- return -EFBIG;
- syms[i].addr = (long) addr;
- syms[i].name = strdup(func);
- i++;
+ ret = libbpf_ensure_mem((void **) &ksyms->syms, &ksyms->sym_cap,
+ sizeof(struct ksym), ksyms->sym_cnt + 1);
+ if (ret)
+ goto error;
+ ret = ksyms__add_symbol(ksyms, func, (unsigned long)addr);
+ if (ret)
+ goto error;
}
fclose(f);
- sym_cnt = i;
- qsort(syms, sym_cnt, sizeof(struct ksym), ksym_cmp);
- return 0;
+ qsort(ksyms->syms, ksyms->sym_cnt, sizeof(struct ksym), ksym_cmp);
+ return ksyms;
+
+error:
+ fclose(f);
+ free_kallsyms_local(ksyms);
+ return NULL;
}
int load_kallsyms(void)
{
- /*
- * This is called/used from multiplace places,
- * load symbols just once.
- */
- if (sym_cnt)
- return 0;
- return load_kallsyms_refresh();
+ pthread_mutex_lock(&ksyms_mutex);
+ if (!ksyms)
+ ksyms = load_kallsyms_local();
+ pthread_mutex_unlock(&ksyms_mutex);
+ return ksyms ? 0 : 1;
}
-struct ksym *ksym_search(long key)
+struct ksym *ksym_search_local(struct ksyms *ksyms, long key)
{
- int start = 0, end = sym_cnt;
+ int start = 0, end = ksyms->sym_cnt;
int result;
/* kallsyms not loaded. return NULL */
- if (sym_cnt <= 0)
+ if (ksyms->sym_cnt <= 0)
return NULL;
while (start < end) {
size_t mid = start + (end - start) / 2;
- result = key - syms[mid].addr;
+ result = key - ksyms->syms[mid].addr;
if (result < 0)
end = mid;
else if (result > 0)
start = mid + 1;
else
- return &syms[mid];
+ return &ksyms->syms[mid];
}
- if (start >= 1 && syms[start - 1].addr < key &&
- key < syms[start].addr)
+ if (start >= 1 && ksyms->syms[start - 1].addr < key &&
+ key < ksyms->syms[start].addr)
/* valid ksym */
- return &syms[start - 1];
+ return &ksyms->syms[start - 1];
/* out of range. return _stext */
- return &syms[0];
+ return &ksyms->syms[0];
}
-long ksym_get_addr(const char *name)
+struct ksym *ksym_search(long key)
+{
+ if (!ksyms)
+ return NULL;
+ return ksym_search_local(ksyms, key);
+}
+
+long ksym_get_addr_local(struct ksyms *ksyms, const char *name)
{
int i;
- for (i = 0; i < sym_cnt; i++) {
- if (strcmp(syms[i].name, name) == 0)
- return syms[i].addr;
+ for (i = 0; i < ksyms->sym_cnt; i++) {
+ if (strcmp(ksyms->syms[i].name, name) == 0)
+ return ksyms->syms[i].addr;
}
return 0;
}
+long ksym_get_addr(const char *name)
+{
+ if (!ksyms)
+ return 0;
+ return ksym_get_addr_local(ksyms, name);
+}
+
/* open kallsyms and read symbol addresses on the fly. Without caching all symbols,
* this is faster than load + find.
*/