From 90574a9c02f1ed46d9d8fec222fbcf375eb90e9b Mon Sep 17 00:00:00 2001 From: Lukas Bulwahn Date: Fri, 6 Nov 2020 04:40:05 +0100 Subject: printk: remove unneeded dead-store assignment make clang-analyzer on x86_64 defconfig caught my attention with: kernel/printk/printk_ringbuffer.c:885:3: warning: Value stored to 'desc' is never read [clang-analyzer-deadcode.DeadStores] desc = to_desc(desc_ring, head_id); ^ Commit b6cf8b3f3312 ("printk: add lockless ringbuffer") introduced desc_reserve() with this unneeded dead-store assignment. As discussed with John Ogness privately, this is probably just some minor left-over from previous iterations of the ringbuffer implementation. So, simply remove this unneeded dead assignment to make clang-analyzer happy. As compilers will detect this unneeded assignment and optimize this anyway, the resulting object code is identical before and after this change. No functional change. No change to object code. Signed-off-by: Lukas Bulwahn Reviewed-by: Sergey Senozhatsky Reviewed-by: John Ogness Reviewed-by: Nathan Chancellor Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20201106034005.18822-1-lukas.bulwahn@gmail.com --- kernel/printk/printk_ringbuffer.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/kernel/printk/printk_ringbuffer.c b/kernel/printk/printk_ringbuffer.c index 24a960a89aa8..dd43c4cf16fb 100644 --- a/kernel/printk/printk_ringbuffer.c +++ b/kernel/printk/printk_ringbuffer.c @@ -882,8 +882,6 @@ static bool desc_reserve(struct printk_ringbuffer *rb, unsigned long *id_out) head_id = atomic_long_read(&desc_ring->head_id); /* LMM(desc_reserve:A) */ do { - desc = to_desc(desc_ring, head_id); - id = DESC_ID(head_id + 1); id_prev_wrap = DESC_ID_PREV_WRAP(desc_ring, id); -- cgit v1.2.3