Fix: integer endianness metadata generation

[lttng-modules.git] / lttng-events.c

diff --git a/lttng-events.c b/lttng-events.c
index f4337397c1e83ab4dcd788e7d9ae43de48f82272..f9a19190ffc03be47ab8f8196a49f180c1b8dbc0 100644 (file)
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -50,6 +50,7 @@
 #include "lttng-events.h"
 #include "lttng-tracer.h"
 #include "lttng-abi-old.h"
+#include "lttng-endian.h"
 #include "wrapper/vzalloc.h"
 
 #define METADATA_CACHE_DEFAULT_SIZE 4096
@@ -329,8 +330,23 @@ int lttng_event_enable(struct lttng_event *event)
                ret = -EEXIST;
                goto end;
        }
-       ACCESS_ONCE(event->enabled) = 1;
-       lttng_session_sync_enablers(event->chan->session);
+       switch (event->instrumentation) {
+       case LTTNG_KERNEL_TRACEPOINT:
+       case LTTNG_KERNEL_SYSCALL:
+               ret = -EINVAL;
+               break;
+       case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_NOOP:
+               ACCESS_ONCE(event->enabled) = 1;
+               break;
+       case LTTNG_KERNEL_KRETPROBE:
+               ret = lttng_kretprobes_event_enable_state(event, 1);
+               break;
+       default:
+               WARN_ON_ONCE(1);
+               ret = -EINVAL;
+       }
 end:
        mutex_unlock(&sessions_mutex);
        return ret;
@@ -349,8 +365,23 @@ int lttng_event_disable(struct lttng_event *event)
                ret = -EEXIST;
                goto end;
        }
-       ACCESS_ONCE(event->enabled) = 0;
-       lttng_session_sync_enablers(event->chan->session);
+       switch (event->instrumentation) {
+       case LTTNG_KERNEL_TRACEPOINT:
+       case LTTNG_KERNEL_SYSCALL:
+               ret = -EINVAL;
+               break;
+       case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_NOOP:
+               ACCESS_ONCE(event->enabled) = 0;
+               break;
+       case LTTNG_KERNEL_KRETPROBE:
+               ret = lttng_kretprobes_event_enable_state(event, 0);
+               break;
+       default:
+               WARN_ON_ONCE(1);
+               ret = -EINVAL;
+       }
 end:
        mutex_unlock(&sessions_mutex);
        return ret;
@@ -538,7 +569,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                smp_wmb();
                break;
        case LTTNG_KERNEL_KPROBE:
-               event->enabled = 1;
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
                event->registered = 1;
                /*
                 * Populate lttng_event structure before event
@@ -562,7 +597,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                struct lttng_event *event_return;
 
                /* kretprobe defines 2 events */
-               event->enabled = 1;
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
                event->registered = 1;
                event_return =
                        kmem_cache_zalloc(event_cache, GFP_KERNEL);
@@ -573,7 +612,7 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                event_return->chan = chan;
                event_return->filter = filter;
                event_return->id = chan->free_event_id++;
-               event_return->enabled = 1;
+               event_return->enabled = 0;
                event_return->registered = 1;
                event_return->instrumentation = itype;
                /*
@@ -608,7 +647,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                break;
        }
        case LTTNG_KERNEL_FUNCTION:
-               event->enabled = 1;
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
                event->registered = 1;
                /*
                 * Populate lttng_event structure before event
@@ -626,7 +669,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                break;
        case LTTNG_KERNEL_NOOP:
        case LTTNG_KERNEL_SYSCALL:
-               event->enabled = 1;
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
                event->registered = 0;
                event->desc = event_desc;
                if (!event->desc) {
@@ -997,17 +1044,22 @@ int lttng_session_list_tracker_pids(struct lttng_session *session)
                ret = PTR_ERR(tracker_pids_list_file);
                goto file_error;
        }
+       if (atomic_long_add_unless(&session->file->f_count,
+               1, INT_MAX) == INT_MAX) {
+               goto refcount_error;
+       }
        ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
        if (ret < 0)
                goto open_error;
        m = tracker_pids_list_file->private_data;
        m->private = session;
        fd_install(file_fd, tracker_pids_list_file);
-       atomic_long_inc(&session->file->f_count);
 
        return file_fd;
 
 open_error:
+       atomic_long_dec(&session->file->f_count);
+refcount_error:
        fput(tracker_pids_list_file);
 file_error:
        put_unused_fd(file_fd);
@@ -1585,7 +1637,7 @@ int _lttng_field_statedump(struct lttng_session *session,
                                        ? "UTF8"
                                        : "ASCII",
                        field->type.u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if __BYTE_ORDER == __BIG_ENDIAN
                        field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
 #else
                        field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
@@ -1614,7 +1666,7 @@ int _lttng_field_statedump(struct lttng_session *session,
                                        ? "UTF8"
                                        : "ASCII",
                        elem_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if __BYTE_ORDER == __BIG_ENDIAN
                        elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
 #else
                        elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
@@ -1640,7 +1692,7 @@ int _lttng_field_statedump(struct lttng_session *session,
                                        ? "UTF8"
                                        : "ASCII"),
                        length_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if __BYTE_ORDER == __BIG_ENDIAN
                        length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
 #else
                        length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
@@ -1660,7 +1712,7 @@ int _lttng_field_statedump(struct lttng_session *session,
                                        ? "UTF8"
                                        : "ASCII"),
                        elem_type->u.basic.integer.base,
-#ifdef __BIG_ENDIAN
+#if __BYTE_ORDER == __BIG_ENDIAN
                        elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
 #else
                        elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
@@ -1909,11 +1961,14 @@ int _lttng_event_header_declare(struct lttng_session *session)
  * taken at start of trace.
  * Yes, this is only an approximation. Yes, we can (and will) do better
  * in future versions.
+ * Return 0 if offset is negative. It may happen if the system sets
+ * the REALTIME clock to 0 after boot.
  */
 static
 uint64_t measure_clock_offset(void)
 {
-       uint64_t offset, monotonic[2], realtime;
+       uint64_t monotonic_avg, monotonic[2], realtime;
+       int64_t offset;
        struct timespec rts = { 0, 0 };
        unsigned long flags;
 
@@ -1924,10 +1979,12 @@ uint64_t measure_clock_offset(void)
        monotonic[1] = trace_clock_read64();
        local_irq_restore(flags);
 
-       offset = (monotonic[0] + monotonic[1]) >> 1;
+       monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
        realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC;
        realtime += rts.tv_nsec;
-       offset = realtime - offset;
+       offset = (int64_t) realtime - monotonic_avg;
+       if (offset < 0)
+               return 0;
        return offset;
 }
 
@@ -1985,7 +2042,7 @@ int _lttng_session_metadata_statedump(struct lttng_session *session)
                CTF_SPEC_MAJOR,
                CTF_SPEC_MINOR,
                uuid_s,
-#ifdef __BIG_ENDIAN
+#if __BYTE_ORDER == __BIG_ENDIAN
                "be"
 #else
                "le"
@@ -2139,6 +2196,9 @@ static int __init lttng_events_init(void)
        if (ret)
                return ret;
        ret = wrapper_get_pfnblock_flags_mask_init();
+       if (ret)
+               return ret;
+       ret = wrapper_get_pageblock_flags_mask_init();
        if (ret)
                return ret;
        ret = lttng_context_init();