alloc_contig_range is the core worker function for CMA allocation so it has every information to be able to understand allocation latency. For example, how many pages are migrated, how many time unmap was needed to migrate pages, how many times it encountered errors by some reasons. This patch adds such statistics in the alloc_contig_range and return it to user so user can use those information to analyize latency. The cma_alloc is first user for the statistics, which export the statistics as new trace event(i.e., cma_alloc_info). It was really usefuli to optimize cma allocation work. Bug: 192475091 Signed-off-by: Minchan Kim <minchan@google.com> Change-Id: I7be43cc89d11078e2a324d2d06aada6d8e9e1cc9
1.8 KiB
1.8 KiB