summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLukas Bulwahn <lukas.bulwahn@gmail.com>2020-12-15 04:12:18 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-15 21:13:45 +0100
commit2b47a24cee0eedbb9b106ef3e992db0ddf48f740 (patch)
treefd64486e3bf2af0476feaf237eb1513b34e4b315
parentmm: don't wake kswapd prematurely when watermark boosting is disabled (diff)
downloadlinux-2b47a24cee0eedbb9b106ef3e992db0ddf48f740.tar.xz
linux-2b47a24cee0eedbb9b106ef3e992db0ddf48f740.zip
mm/vmscan: drop unneeded assignment in kswapd()
The refactoring to kswapd() in commit e716f2eb24de ("mm, vmscan: prevent kswapd sleeping prematurely due to mismatched classzone_idx") turned an assignment to reclaim_order into a dead store, as in all further paths, reclaim_order will be assigned again before it is used. make clang-analyzer on x86_64 tinyconfig caught my attention with: mm/vmscan.c: warning: Although the value stored to 'reclaim_order' is used in the enclosing expression, the value is never actually read from 'reclaim_order' [clang-analyzer-deadcode.DeadStores] Compilers will detect this unneeded assignment and optimize this anyway. So, the resulting binary is identical before and after this change. Simplify the code and remove unneeded assignment to make clang-analyzer happy. No functional change. No change in binary code. Link: https://lkml.kernel.org/r/20201004125827.17679-1-lukas.bulwahn@gmail.com Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--mm/vmscan.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 0ec6321e9887..e71b563cda7b 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3895,7 +3895,7 @@ kswapd_try_sleep:
highest_zoneidx);
/* Read the new order and highest_zoneidx */
- alloc_order = reclaim_order = READ_ONCE(pgdat->kswapd_order);
+ alloc_order = READ_ONCE(pgdat->kswapd_order);
highest_zoneidx = kswapd_highest_zoneidx(pgdat,
highest_zoneidx);
WRITE_ONCE(pgdat->kswapd_order, 0);