From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: bpf@vger.kernel.org
Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org,
vbabka@suse.cz, linux-mm@kvack.org, kernel-team@fb.com
Subject: [PATCH bpf-next] mm: Fix the flipped condition in gfpflags_allow_spinning()
Date: Mon, 10 Mar 2025 13:40:17 +0100 [thread overview]
Message-ID: <20250310124017.187-1-alexei.starovoitov@gmail.com> (raw)
From: Vlastimil Babka <vbabka@suse.cz>
The function gfpflags_allow_spinning() has a bug that makes it return
the opposite result than intended. This could contribute to deadlocks as
usage profilerates, for now it was noticed as a performance regression
due to try_charge_memcg() not refilling memcg stock when it could. Fix
the flipped condition.
Fixes: 97769a53f117 ("mm, bpf: Introduce try_alloc_pages() for opportunistic page allocation")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202503101254.cfd454df-lkp@intel.com
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
include/linux/gfp.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index ceb226c2e25c..c9fa6309c903 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -55,7 +55,7 @@ static inline bool gfpflags_allow_spinning(const gfp_t gfp_flags)
* regular page allocator doesn't fully support this
* allocation mode.
*/
- return !(gfp_flags & __GFP_RECLAIM);
+ return !!(gfp_flags & __GFP_RECLAIM);
}
#ifdef CONFIG_HIGHMEM
--
2.43.5
next reply other threads:[~2025-03-10 12:40 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-10 12:40 Alexei Starovoitov [this message]
2025-03-10 22:30 ` patchwork-bot+netdevbpf
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