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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: 2FB001C0019 X-Rspamd-Server: rspam01 X-Stat-Signature: s1ojkrtmj3fy73bwuogtsgz93f5muzig X-HE-Tag: 1722236263-480545 X-HE-Meta: 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 qSLD1kGx S9SAvNNe/MHYod4SZ49WtTG5E0tyusA4hbQePN2FiCSkB2SzOxFQm5IKOYG7bQqcjrS9l2/Bjcm4heMQy7lrZggf67o87H7slERF1vGXzVNHY/ANxlv3vzC+aScn1N4+kby2qSgu2DBz7c3iXPUL8SYNlXl/20P7P267/zmYyIoFwRWcgiy7J92nrFhKcEYzLYr/LK/YjfqsGfmMfdK1Fnw2ibXjC7YtrFEti9Qs3f7f9d/YQnjKywzK3Tw== 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 7/28/24 18:13, Mike Rapoport wrote: > On Fri, Jul 26, 2024 at 04:10:23PM +0900, Leesoo Ahn wrote: >> sparse_buffer_fini(..) takes the following actions even though the value of >> sparsemap_buf is NULL, >> 1. calculate size of sparsemap buffer (which is meaningless). >> 2. set sparsemap_buf variable to NULL (although it is already NULL). >> >> These steps are unnecessary if the variable, sparsemap_buf is NULL. >> >> Refactor the function to return right away if the variable is NULL. >> Hence, it doesn't need to take further actions. > > sparse_buffer_fini() is called a few times on init so saving a jump (if at > all) does not worth the churn. Agreed, this is not worth the churn given there could be just a single call instance for sparse_buffer_fini(), either in normal or error path in sparse_init_nid(). > >> Signed-off-by: Leesoo Ahn >> --- >> mm/sparse.c | 8 ++++++-- >> 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/mm/sparse.c b/mm/sparse.c >> index e4b830091d13..091e4bc2f72c 100644 >> --- a/mm/sparse.c >> +++ b/mm/sparse.c >> @@ -469,9 +469,13 @@ static void __init sparse_buffer_init(unsigned long size, int nid) >> >> static void __init sparse_buffer_fini(void) >> { >> - unsigned long size = sparsemap_buf_end - sparsemap_buf; >> + unsigned long size; >> >> - if (sparsemap_buf && size > 0) >> + if (!sparsemap_buf) >> + return; >> + >> + size = sparsemap_buf_end - sparsemap_buf; >> + if (size > 0) >> sparse_buffer_free(size); >> sparsemap_buf = NULL; >> } >> -- >> 2.34.1 >> >> >