Em Sat, Jun 27, 2015 at 05:08:20PM +0800, Hou Pengyang escreveu: > There is something about MAP_HUGETLB. > In this patch, we check if a mmap area is hugetlbfs area by MAP_HUGETLB, > a bit in MMAP2 event. > However, if mmap area is hugetlb related, MAP_HUGETLB does not always > appear. Because, there are two ways generating MMAP2 event. > 1) when a new vm_area_struct is created, its info would be exported > as a MMAP2 event. > 2) perf reads /proc/pid/maps for generating MMAP2 event. > MAP_HUGETLB appears if MMAP2 event is generated on situation 1), > while not on situation 2). > This is because on situation 2), perf reads /proc/pid/maps, which > contains only PROT_READ/WRITE/EXEC, MAP_SHARED/MAP_PRIVATE, while more > details appear in /proc/pid/smaps, such as MAP_HUGETLB.
Humm: [root@zoo ~]# wc -l /proc/`pidof firefox`/maps 934 /proc/4551/maps [root@zoo ~]# wc -l /proc/`pidof firefox`/smaps 14944 /proc/4551/smaps [root@zoo ~]# > So I wonder if there is a need to read /proc/pid/smaps instead of > /proc/pid/maps to generate MMAP2 event. Or we should solve the problem by > another way? Doing some research now... - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
