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[2003:d8:2f1f:3600:dc8:26ee:9aa9:fdc7]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4562e8018a4sm48479605e9.9.2025.07.17.04.44.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 17 Jul 2025 04:44:13 -0700 (PDT) Message-ID: <2fdacd57-2314-47c7-9eeb-6928221ce516@redhat.com> Date: Thu, 17 Jul 2025 13:44:12 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] selftests/mm: refactor common code and improve test skipping in guard_region To: wang lian , akpm@linux-foundation.org, broonie@kernel.org, lorenzo.stoakes@oracle.com, sj@kernel.org, ziy@nvidia.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: brauner@kernel.org, gkwang@linx-info.com, jannh@google.com, Liam.Howlett@oracle.com, ludovico.zy.wu@gmail.com, p1ucky0923@gmail.com, richard.weiyang@gmail.com, ryncsn@gmail.com, shuah@kernel.org, vbabka@suse.cz, zijing.zhang@proton.me References: <20250717112407.13507-1-lianux.mm@gmail.com> <20250717112407.13507-2-lianux.mm@gmail.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: djxrytwz9sqaehrs56545tp6tfw4uciy X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: EC74980008 X-Rspam-User: X-HE-Tag: 1752752660-948307 X-HE-Meta: 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 NvuxuOhN 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 17.07.25 13:24, wang lian wrote: > Move the generic `FORCE_READ` macro from `guard-regions.c` to the shared > `vm_util.h` header to promote code reuse. > > In `guard-regions.c`, replace `ksft_exit_skip()` with the `SKIP()` macro > to ensure only the current test is skipped on permission failure, instead > of terminating the entire test binary. > > Signed-off-by: wang lian > Reviewed-by: Lorenzo Stoakes > --- > tools/testing/selftests/mm/guard-regions.c | 9 +-------- > tools/testing/selftests/mm/vm_util.h | 7 +++++++ > 2 files changed, 8 insertions(+), 8 deletions(-) > > diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c > index 93af3d3760f9..b0d42eb04e3a 100644 > --- a/tools/testing/selftests/mm/guard-regions.c > +++ b/tools/testing/selftests/mm/guard-regions.c > @@ -35,13 +35,6 @@ > static volatile sig_atomic_t signal_jump_set; > static sigjmp_buf signal_jmp_buf; > > -/* > - * Ignore the checkpatch warning, we must read from x but don't want to do > - * anything with it in order to trigger a read page fault. We therefore must use > - * volatile to stop the compiler from optimising this away. > - */ > -#define FORCE_READ(x) (*(volatile typeof(x) *)x) > - > /* > * How is the test backing the mapping being tested? > */ > @@ -582,7 +575,7 @@ TEST_F(guard_regions, process_madvise) > > /* OK we don't have permission to do this, skip. */ > if (count == -1 && errno == EPERM) > - ksft_exit_skip("No process_madvise() permissions, try running as root.\n"); > + SKIP(return, "No process_madvise() permissions, try running as root.\n"); > > /* Returns the number of bytes advised. */ > ASSERT_EQ(count, 6 * page_size); > diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h > index 2b154c287591..c20298ae98ea 100644 > --- a/tools/testing/selftests/mm/vm_util.h > +++ b/tools/testing/selftests/mm/vm_util.h > @@ -18,6 +18,13 @@ > #define PM_SWAP BIT_ULL(62) > #define PM_PRESENT BIT_ULL(63) > > +/* > + * Ignore the checkpatch warning, we must read from x but don't want to do > + * anything with it in order to trigger a read page fault. We therefore must use > + * volatile to stop the compiler from optimising this away. > + */ > +#define FORCE_READ(x) (*(volatile typeof(x) *)x) > + > extern unsigned int __page_size; > extern unsigned int __page_shift; > The FORCE_READ() stuff belongs into patch #2. -- Cheers, David / dhildenb