Update comments regarding the power of 2 constraint on sub-buffer sizes

[lttng-tools.git] / src / bin / lttng-sessiond / lttng-ust-abi.h

diff --git a/src/bin/lttng-sessiond/lttng-ust-abi.h b/src/bin/lttng-sessiond/lttng-ust-abi.h
index a3298caa2778435ca34cdec4ab508e940694346b..27771e25da55d29ecca9b4a272f16212db8d54d4 100644 (file)
--- a/src/bin/lttng-sessiond/lttng-ust-abi.h
+++ b/src/bin/lttng-sessiond/lttng-ust-abi.h
@@ -140,8 +140,15 @@ enum lttng_ust_context_type {
        LTTNG_UST_CONTEXT_PTHREAD_ID            = 2,
        LTTNG_UST_CONTEXT_PROCNAME              = 3,
        LTTNG_UST_CONTEXT_IP                    = 4,
+       LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER   = 5,
 };
 
+struct lttng_ust_perf_counter_ctx {
+       uint32_t type;
+       uint64_t config;
+       char name[LTTNG_UST_SYM_NAME_LEN];
+} LTTNG_PACKED;
+
 #define LTTNG_UST_CONTEXT_PADDING1     16
 #define LTTNG_UST_CONTEXT_PADDING2     (LTTNG_UST_SYM_NAME_LEN + 32)
 struct lttng_ust_context {
@@ -149,6 +156,7 @@ struct lttng_ust_context {
        char padding[LTTNG_UST_CONTEXT_PADDING1];
 
        union {
+               struct lttng_ust_perf_counter_ctx perf_counter;
                char padding[LTTNG_UST_CONTEXT_PADDING2];
        } u;
 } LTTNG_PACKED;
@@ -158,7 +166,7 @@ struct lttng_ust_context {
  */
 #define LTTNG_UST_CHANNEL_ATTR_PADDING (LTTNG_UST_SYM_NAME_LEN + 32)
 struct lttng_ust_channel_attr {
-       uint64_t subbuf_size;                   /* bytes */
+       uint64_t subbuf_size;                   /* bytes, power of 2 */
        uint64_t num_subbuf;                    /* power of 2 */
        int overwrite;                          /* 1: overwrite, 0: discard */
        unsigned int switch_timer_interval;     /* usec */