[PATCH] mm/page_alloc: Revert pahole zero-sized workaround
From: Mel Gorman <hidden>
Date: 2021-07-05 09:51:23
Subsystem:
library code, memory management, memory management - page allocator, the rest · Maintainers:
Andrew Morton, Vlastimil Babka, Linus Torvalds
Commit dbbee9d5cd83 ("mm/page_alloc: convert per-cpu list protection to
local_lock") folded in a workaround patch for pahole that was unable to
deal with zero-sized percpu structures. A superior workaround is achieved
with commit a0b8200d06ad ("kbuild: skip per-CPU BTF generation for pahole
v1.18-v1.21"). This patch reverts the dummy field and the pahole version
check.
Fixes: dbbee9d5cd83 ("mm/page_alloc: convert per-cpu list protection to local_lock")
Signed-off-by: Mel Gorman <redacted>
---
lib/Kconfig.debug | 3 ---
mm/page_alloc.c | 11 -----------
2 files changed, 14 deletions(-)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 8acc01d7d816..5cf2585b78a1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug@@ -313,9 +313,6 @@ config DEBUG_INFO_BTF config PAHOLE_HAS_SPLIT_BTF def_bool $(success, test `$(PAHOLE) --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'` -ge "119") -config PAHOLE_HAS_ZEROSIZE_PERCPU_SUPPORT - def_bool $(success, test `$(PAHOLE) --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'` -ge "122") - config DEBUG_INFO_BTF_MODULES def_bool y depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d6e94cc8066c..3b97e17806be 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c@@ -124,17 +124,6 @@ static DEFINE_MUTEX(pcp_batch_high_lock); struct pagesets { local_lock_t lock; -#if defined(CONFIG_DEBUG_INFO_BTF) && \ - !defined(CONFIG_DEBUG_LOCK_ALLOC) && \ - !defined(CONFIG_PAHOLE_HAS_ZEROSIZE_PERCPU_SUPPORT) - /* - * pahole 1.21 and earlier gets confused by zero-sized per-CPU - * variables and produces invalid BTF. Ensure that - * sizeof(struct pagesets) != 0 for older versions of pahole. - */ - char __pahole_hack; - #warning "pahole too old to support zero-sized struct pagesets" -#endif }; static DEFINE_PER_CPU(struct pagesets, pagesets) = { .lock = INIT_LOCAL_LOCK(lock),