Fix: poll compat layer reallocation new size

[lttng-tools.git] / src / common / compat / compat-epoll.c

diff --git a/src/common/compat/compat-epoll.c b/src/common/compat/compat-epoll.c
index f014a0d783d434f57fc95a5c17e126f62946e74e..903a9f8256eeafad9e678f565ba6c1b60f0e9c2a 100644 (file)
--- a/src/common/compat/compat-epoll.c
+++ b/src/common/compat/compat-epoll.c
@@ -27,6 +27,8 @@
 
 #include <common/error.h>
 #include <common/defaults.h>
+#include <common/macros.h>
+#include <common/utils.h>
 
 #include "poll.h"
 
@@ -201,11 +203,15 @@ int compat_epoll_wait(struct lttng_poll_event *events, int timeout)
         */
        if (events->nb_fd > events->alloc_size) {
                /* Expand if the nb_fd is higher than the actual size. */
-               new_size = events->alloc_size << 1UL;
+               new_size = max_t(uint32_t,
+                               1U << utils_get_count_order_u32(events->nb_fd),
+                               events->alloc_size << 1UL);
        } else if ((events->nb_fd << 1UL) <= events->alloc_size &&
                        events->nb_fd >= events->init_size) {
                /* Shrink if nb_fd multiplied by two is <= than the actual size. */
-               new_size = events->alloc_size >> 1UL;
+               new_size = max_t(uint32_t,
+                               utils_get_count_order_u32(events->nb_fd) >> 1U,
+                               events->alloc_size >> 1U);
        } else {
                /* Indicate that we don't want to resize. */
                new_size = 0;