From 543e2d61e6047208d647cf3fd3499bead3bcc23e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Amaury=20S=C3=A9chet?= Date: Thu, 2 Mar 2023 23:32:42 +0000 Subject: [PATCH] Simplify the logic in ph_insert Also fixes what looks like an off by one error in the lazy aux list merge part of the code that previously never touched the last node in the aux list. --- include/jemalloc/internal/ph.h | 59 +++++++++++++++++----------------- 1 file changed, 30 insertions(+), 29 deletions(-) diff --git a/include/jemalloc/internal/ph.h b/include/jemalloc/internal/ph.h index 5f091c5f..8ceadb90 100644 --- a/include/jemalloc/internal/ph.h +++ b/include/jemalloc/internal/ph.h @@ -318,36 +318,37 @@ ph_insert(ph_t *ph, void *phn, size_t offset, ph_cmp_t cmp) { */ if (ph->root == NULL) { ph->root = phn; - } else { - /* - * As a special case, check to see if we can replace the root. - * This is practically common in some important cases, and lets - * us defer some insertions (hopefully, until the point where - * some of the items in the aux list have been removed, savings - * us from linking them at all). - */ - if (cmp(phn, ph->root) < 0) { - phn_lchild_set(phn, ph->root, offset); - phn_prev_set(ph->root, phn, offset); - ph->root = phn; - ph->auxcount = 0; - return; - } - ph->auxcount++; - phn_next_set(phn, phn_next_get(ph->root, offset), offset); - if (phn_next_get(ph->root, offset) != NULL) { - phn_prev_set(phn_next_get(ph->root, offset), phn, - offset); - } - phn_prev_set(phn, ph->root, offset); - phn_next_set(ph->root, phn, offset); + return; } - if (ph->auxcount > 1) { - unsigned nmerges = ffs_zu(ph->auxcount - 1); - bool done = false; - for (unsigned i = 0; i < nmerges && !done; i++) { - done = ph_try_aux_merge_pair(ph, offset, cmp); - } + + /* + * As a special case, check to see if we can replace the root. + * This is practically common in some important cases, and lets + * us defer some insertions (hopefully, until the point where + * some of the items in the aux list have been removed, savings + * us from linking them at all). + */ + if (cmp(phn, ph->root) < 0) { + phn_lchild_set(phn, ph->root, offset); + phn_prev_set(ph->root, phn, offset); + ph->root = phn; + ph->auxcount = 0; + return; + } + + phn_next_set(phn, phn_next_get(ph->root, offset), offset); + if (phn_next_get(ph->root, offset) != NULL) { + phn_prev_set(phn_next_get(ph->root, offset), phn, + offset); + } + phn_prev_set(phn, ph->root, offset); + phn_next_set(ph->root, phn, offset); + + ph->auxcount++; + unsigned nmerges = ffs_zu(ph->auxcount); + bool done = false; + for (unsigned i = 0; i < nmerges && !done; i++) { + done = ph_try_aux_merge_pair(ph, offset, cmp); } }