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From: Ye Liu In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 2D53D1C0007 X-Stat-Signature: m77si3quwrn3wkokoiqhnyudgsbqffix X-Rspam-User: X-HE-Tag: 1755221906-71885 X-HE-Meta: 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 MJ0/5cYC jltmUoyOIClYm+ORXH3oxwKcR8ik0GwlUsQ1lW7wWwDyLhSpeNU9bM+KJ8t5Wi/DYxMw9NdGjH5c8lAlK2ho2VvSxELvTWBhRfKeWkpxrQ++MWvreiACbg825JptPqkcHSPpL6MJAJvYpsCpMjATjlV0KlGpxIiuq9OaPbmujscd2amOswpY3q+TIransAfwBlOJs8gSjrVd8WCd7NpX+gDrkxzOB+j+92fEp00z4TuoJW5gEKXpc+T7n2WBCFCdsrwtGWGNeQ3+jxLg= 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: 在 2025/8/14 22:47, Zi Yan 写道: > On 14 Aug 2025, at 5:00, Ye Liu wrote: > >> From: Ye Liu >> >> Use max() macro to simplify the calculation of maximum lowmem_reserve >> value in calculate_totalreserve_pages(), instead of open-coding the >> comparison. The functionality remains identical. >> >> Signed-off-by: Ye Liu >> --- >> mm/page_alloc.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 64872214bc7d..8a55a4951d19 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -6236,8 +6236,7 @@ static void calculate_totalreserve_pages(void) >> >> /* Find valid and maximum lowmem_reserve in the zone */ >> for (j = i; j < MAX_NR_ZONES; j++) { >> - if (zone->lowmem_reserve[j] > max) >> - max = zone->lowmem_reserve[j]; >> + max = max(max, zone->lowmem_reserve[j]); >> } > > There is a “if (max > managed_pages)” below. Maybe convert that as well? I should use min() here, but I noticed the two variables have different types: one is 'long' and the other is 'unsigned long'. So, I should use min_t(). But then again, why is lowmem_reserve of type 'long'? It should be a non-negative number, right? Is it possible to change the type of lowmem_reserve to 'unsigned long' and change all uses of it at the same time? Is it necessary? > > Feel free to add Acked-by: Zi Yan . > > Best Regards, > Yan, Zi -- Thanks, Ye Liu