Linux Kernel Markers
The marker activation functions sits in kernel/marker.c. A hash table is used
to keep track of the registered probes and armed markers, so the markers
within a newly loaded module that should be active can be activated at module
load time.
marker_query has been removed. marker_get_first, marker_get_next and
marker_release should be used as iterators on the markers.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Mason <mmlnx@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/module.c b/kernel/module.c
index 7734595..3202c99 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1673,6 +1673,8 @@
unsigned int unusedcrcindex;
unsigned int unusedgplindex;
unsigned int unusedgplcrcindex;
+ unsigned int markersindex;
+ unsigned int markersstringsindex;
struct module *mod;
long err = 0;
void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
@@ -1939,6 +1941,9 @@
add_taint_module(mod, TAINT_FORCED_MODULE);
}
#endif
+ markersindex = find_sec(hdr, sechdrs, secstrings, "__markers");
+ markersstringsindex = find_sec(hdr, sechdrs, secstrings,
+ "__markers_strings");
/* Now do relocations. */
for (i = 1; i < hdr->e_shnum; i++) {
@@ -1961,6 +1966,11 @@
if (err < 0)
goto cleanup;
}
+#ifdef CONFIG_MARKERS
+ mod->markers = (void *)sechdrs[markersindex].sh_addr;
+ mod->num_markers =
+ sechdrs[markersindex].sh_size / sizeof(*mod->markers);
+#endif
/* Find duplicate symbols */
err = verify_export_symbols(mod);
@@ -1979,6 +1989,11 @@
add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);
+#ifdef CONFIG_MARKERS
+ if (!mod->taints)
+ marker_update_probe_range(mod->markers,
+ mod->markers + mod->num_markers, NULL, NULL);
+#endif
err = module_finalize(hdr, sechdrs, mod);
if (err < 0)
goto cleanup;
@@ -2570,3 +2585,18 @@
void struct_module(struct module *mod) { return; }
EXPORT_SYMBOL(struct_module);
#endif
+
+#ifdef CONFIG_MARKERS
+void module_update_markers(struct module *probe_module, int *refcount)
+{
+ struct module *mod;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry(mod, &modules, list)
+ if (!mod->taints)
+ marker_update_probe_range(mod->markers,
+ mod->markers + mod->num_markers,
+ probe_module, refcount);
+ mutex_unlock(&module_mutex);
+}
+#endif