[Crash-utility] [PATCH] improve the performance of kmem -s [address]

Hello Dave, These two patches are used to improve the performance of "kmem -s [address]". Current code need to search all kmem_caches twice. It is a waste of time. With my patch, the address is sent to "dump_kmem_cache" function to make the second search be restricted to the kmem_cache found in the first search. It means the second search is neglected. I have implemented the improvement for three types of kmem_cache. The search for "slub" does not waste that much time as its peers, so I did not modify the code related to "slub". Additionally, I only get the environment to test my first patch, so the second patch has not been tested. Here is the statistic of my test on RHEL6.2 x86_64, the vmcore used for testing has about 150000 kmem_caches commands in file: 1. only 'quit' origin code : about 36s with patch : about 36s 2. 1 time of searching the 100000th kmem_cache origin code : about 59s with patch : about 39s 3. 100 times of searching the 100000th kmem_cache origin code : about 38min30s with patch : about 5min p.s. If I create a kmem_cache called "list", a little confusion may happen when using "kmem -s list". I am wondering is it necessary to introduce an another option replacing list to avoid such collision. -- -- Regards Qiao Nuohan