The following commit has been merged into the perf/core branch of tip: Commit-ID: c554aa9ca976480839af342204e05bb4ce8367d5 Gitweb: https://git.kernel.org/tip/c554aa9ca976480839af342204e05bb4ce8367d5 Author: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> AuthorDate: Fri, 01 Nov 2024 22:13:33 +01:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Mon, 11 Nov 2024 11:49:48 +01:00 uprobes: Re-order struct uprobe_task to save some space On x86_64, with allmodconfig, struct uprobe_task is 72 bytes long, with a hole and some padding. /* size: 72, cachelines: 2, members: 7 */ /* sum members: 64, holes: 1, sum holes: 4 */ /* padding: 4 */ /* forced alignments: 1, forced holes: 1, sum forced holes: 4 */ /* last cacheline: 8 bytes */ Reorder the structure to fill the hole and avoid the padding. This way, the whole structure fits in a single cacheline and some memory is saved when it is allocated. /* size: 64, cachelines: 1, members: 7 */ /* forced alignments: 1 */ Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: "Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx> Link: https://lore.kernel.org/r/a9f541d0cedf421f765c77a1fb93d6a979778a88.1730495562.git.christophe.jaillet@xxxxxxxxxx --- include/linux/uprobes.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 7a051b5..e0a4c20 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -121,6 +121,9 @@ struct hprobe { struct uprobe_task { enum uprobe_task_state state; + unsigned int depth; + struct return_instance *return_instances; + union { struct { struct arch_uprobe_task autask; @@ -138,9 +141,6 @@ struct uprobe_task { unsigned long xol_vaddr; struct arch_uprobe *auprobe; - - struct return_instance *return_instances; - unsigned int depth; }; struct return_consumer {