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2011-01-13Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits) Documentation/trace/events.txt: Remove obsolete sched_signal_send. writeback: fix global_dirty_limits comment runtime -> real-time ppc: fix comment typo singal -> signal drivers: fix comment typo diable -> disable. m68k: fix comment typo diable -> disable. wireless: comment typo fix diable -> disable. media: comment typo fix diable -> disable. remove doc for obsolete dynamic-printk kernel-parameter remove extraneous 'is' from Documentation/iostats.txt Fix spelling milisec -> ms in snd_ps3 module parameter description Fix spelling mistakes in comments Revert conflicting V4L changes i7core_edac: fix typos in comments mm/rmap.c: fix comment sound, ca0106: Fix assignment to 'channel'. hrtimer: fix a typo in comment init/Kconfig: fix typo anon_inodes: fix wrong function name in comment fix comment typos concerning "consistent" poll: fix a typo in comment ... Fix up trivial conflicts in: - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c) - fs/ext4/ext4.h Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-08Documentation/trace/events.txt: Remove obsolete sched_signal_send.Tao Ma
'sched_signal_send' doesn't exist in the kernel now. Replace it with 'signal_generate' so that the example in events.txt can be executed successfully. I also change some /debug to /sys/kernel/debug which is debugfs' default mount directory now(similar to commit 52ad51e). Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-01-05tools, perf: Documentation for the power events APIJean Pihet
Provides documentation for the following: - the new power trace API, - the old (legacy) power trace API, - the DEPRECATED Kconfig option usage. Signed-off-by: Jean Pihet <j-pihet@ti.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: trenn@suse.de Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: linux-pm@lists.linux-foundation.org LKML-Reference: <1294253342-29056-3-git-send-email-j-pihet@ti.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-22mm: vmscan: tracepoint: account for scanned pages similarly for both ftrace ↵Mel Gorman
and vmstat When correlating ftrace results with /proc/vmstat, I noticed that the reporting scripts value for "pages scanned" differed significantly. Both values were "right" depending on how you look at it. The difference is due to vmstat only counting scanning of the inactive list towards pages scanned. The analysis script for the tracepoint counts active and inactive list yielding a far higher value than vmstat. The resulting scanning/reclaim ratio looks much worse. The tracepoint is ok but this patch updates the reporting script so that the report values for scanned are similar to vmstat. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26tracing, vmscan: add trace events for LRU list shrinkingMel Gorman
There have been numerous reports of stalls that pointed at the problem being somewhere in the VM. There are multiple roots to the problems which means dealing with any of the root problems in isolation is tricky to justify on their own and they would still need integration testing. This patch series puts together two different patch sets which in combination should tackle some of the root causes of latency problems being reported. Patch 1 adds a tracepoint for shrink_inactive_list. For this series, the most important results is being able to calculate the scanning/reclaim ratio as a measure of the amount of work being done by page reclaim. Patch 2 accounts for time spent in congestion_wait. Patches 3-6 were originally developed by Kosaki Motohiro but reworked for this series. It has been noted that lumpy reclaim is far too aggressive and trashes the system somewhat. As SLUB uses high-order allocations, a large cost incurred by lumpy reclaim will be noticeable. It was also reported during transparent hugepage support testing that lumpy reclaim was trashing the system and these patches should mitigate that problem without disabling lumpy reclaim. Patch 7 adds wait_iff_congested() and replaces some callers of congestion_wait(). wait_iff_congested() only sleeps if there is a BDI that is currently congested. Patch 8 notes that any BDI being congested is not necessarily a problem because there could be multiple BDIs of varying speeds and numberous zones. It attempts to track when a zone being reclaimed contains many pages backed by a congested BDI and if so, reclaimers wait on the congestion queue. I ran a number of tests with monitoring on X86, X86-64 and PPC64. Each machine had 3G of RAM and the CPUs were X86: Intel P4 2-core X86-64: AMD Phenom 4-core PPC64: PPC970MP Each used a single disk and the onboard IO controller. Dirty ratio was left at 20. I'm just going to report for X86-64 and PPC64 in a vague attempt to keep this report short. Four kernels were tested each based on v2.6.36-rc4 traceonly-v2r2: Patches 1 and 2 to instrument vmscan reclaims and congestion_wait lowlumpy-v2r3: Patches 1-6 to test if lumpy reclaim is better waitcongest-v2r3: Patches 1-7 to only wait on congestion waitwriteback-v2r4: Patches 1-8 to detect when a zone is congested nocongest-v1r5: Patches 1-3 for testing wait_iff_congestion nodirect-v1r5: Patches 1-10 to disable filesystem writeback for better IO The tests run were as follows kernbench compile-based benchmark. Smoke test performance sysbench OLTP read-only benchmark. Will be re-run in the future as read-write micro-mapped-file-stream This is a micro-benchmark from Johannes Weiner that accesses a large sparse-file through mmap(). It was configured to run in only single-CPU mode but can be indicative of how well page reclaim identifies suitable pages. stress-highalloc Tries to allocate huge pages under heavy load. kernbench, iozone and sysbench did not report any performance regression on any machine. sysbench did pressure the system lightly and there was reclaim activity but there were no difference of major interest between the kernels. X86-64 micro-mapped-file-stream traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4 pgalloc_dma 1639.00 ( 0.00%) 667.00 (-145.73%) 1167.00 ( -40.45%) 578.00 (-183.56%) pgalloc_dma32 2842410.00 ( 0.00%) 2842626.00 ( 0.01%) 2843043.00 ( 0.02%) 2843014.00 ( 0.02%) pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgsteal_dma 729.00 ( 0.00%) 85.00 (-757.65%) 609.00 ( -19.70%) 125.00 (-483.20%) pgsteal_dma32 2338721.00 ( 0.00%) 2447354.00 ( 4.44%) 2429536.00 ( 3.74%) 2436772.00 ( 4.02%) pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_kswapd_dma 1469.00 ( 0.00%) 532.00 (-176.13%) 1078.00 ( -36.27%) 220.00 (-567.73%) pgscan_kswapd_dma32 4597713.00 ( 0.00%) 4503597.00 ( -2.09%) 4295673.00 ( -7.03%) 3891686.00 ( -18.14%) pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_direct_dma 71.00 ( 0.00%) 134.00 ( 47.01%) 243.00 ( 70.78%) 352.00 ( 79.83%) pgscan_direct_dma32 305820.00 ( 0.00%) 280204.00 ( -9.14%) 600518.00 ( 49.07%) 957485.00 ( 68.06%) pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pageoutrun 16296.00 ( 0.00%) 21254.00 ( 23.33%) 18447.00 ( 11.66%) 20067.00 ( 18.79%) allocstall 443.00 ( 0.00%) 273.00 ( -62.27%) 513.00 ( 13.65%) 1568.00 ( 71.75%) These are based on the raw figures taken from /proc/vmstat. It's a rough measure of reclaim activity. Note that allocstall counts are higher because we are entering direct reclaim more often as a result of not sleeping in congestion. In itself, it's not necessarily a bad thing. It's easier to get a view of what happened from the vmscan tracepoint report. FTrace Reclaim Statistics: vmscan traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4 Direct reclaims 443 273 513 1568 Direct reclaim pages scanned 305968 280402 600825 957933 Direct reclaim pages reclaimed 43503 19005 30327 117191 Direct reclaim write file async I/O 0 0 0 0 Direct reclaim write anon async I/O 0 3 4 12 Direct reclaim write file sync I/O 0 0 0 0 Direct reclaim write anon sync I/O 0 0 0 0 Wake kswapd requests 187649 132338 191695 267701 Kswapd wakeups 3 1 4 1 Kswapd pages scanned 4599269 4454162 4296815 3891906 Kswapd pages reclaimed 2295947 2428434 2399818 2319706 Kswapd reclaim write file async I/O 1 0 1 1 Kswapd reclaim write anon async I/O 59 187 41 222 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 4.34 2.52 6.63 2.96 Time kswapd awake (seconds) 11.15 10.25 11.01 10.19 Total pages scanned 4905237 4734564 4897640 4849839 Total pages reclaimed 2339450 2447439 2430145 2436897 %age total pages scanned/reclaimed 47.69% 51.69% 49.62% 50.25% %age total pages scanned/written 0.00% 0.00% 0.00% 0.00% %age file pages scanned/written 0.00% 0.00% 0.00% 0.00% Percentage Time Spent Direct Reclaim 29.23% 19.02% 38.48% 20.25% Percentage Time kswapd Awake 78.58% 78.85% 76.83% 79.86% What is interesting here for nocongest in particular is that while direct reclaim scans more pages, the overall number of pages scanned remains the same and the ratio of pages scanned to pages reclaimed is more or less the same. In other words, while we are sleeping less, reclaim is not doing more work and as direct reclaim and kswapd is awake for less time, it would appear to be doing less work. FTrace Reclaim Statistics: congestion_wait Direct number congest waited 87 196 64 0 Direct time congest waited 4604ms 4732ms 5420ms 0ms Direct full congest waited 72 145 53 0 Direct number conditional waited 0 0 324 1315 Direct time conditional waited 0ms 0ms 0ms 0ms Direct full conditional waited 0 0 0 0 KSwapd number congest waited 20 10 15 7 KSwapd time congest waited 1264ms 536ms 884ms 284ms KSwapd full congest waited 10 4 6 2 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 The vanilla kernel spent 8 seconds asleep in direct reclaim and no time at all asleep with the patches. MMTests Statistics: duration User/Sys Time Running Test (seconds) 10.51 10.73 10.6 11.66 Total Elapsed Time (seconds) 14.19 13.00 14.33 12.76 Overall, the tests completed faster. It is interesting to note that backing off further when a zone is congested and not just a BDI was more efficient overall. PPC64 micro-mapped-file-stream pgalloc_dma 3024660.00 ( 0.00%) 3027185.00 ( 0.08%) 3025845.00 ( 0.04%) 3026281.00 ( 0.05%) pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgsteal_dma 2508073.00 ( 0.00%) 2565351.00 ( 2.23%) 2463577.00 ( -1.81%) 2532263.00 ( 0.96%) pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_kswapd_dma 4601307.00 ( 0.00%) 4128076.00 ( -11.46%) 3912317.00 ( -17.61%) 3377165.00 ( -36.25%) pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pgscan_direct_dma 629825.00 ( 0.00%) 971622.00 ( 35.18%) 1063938.00 ( 40.80%) 1711935.00 ( 63.21%) pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) pageoutrun 27776.00 ( 0.00%) 20458.00 ( -35.77%) 18763.00 ( -48.04%) 18157.00 ( -52.98%) allocstall 977.00 ( 0.00%) 2751.00 ( 64.49%) 2098.00 ( 53.43%) 5136.00 ( 80.98%) Similar trends to x86-64. allocstalls are up but it's not necessarily bad. FTrace Reclaim Statistics: vmscan Direct reclaims 977 2709 2098 5136 Direct reclaim pages scanned 629825 963814 1063938 1711935 Direct reclaim pages reclaimed 75550 242538 150904 387647 Direct reclaim write file async I/O 0 0 0 2 Direct reclaim write anon async I/O 0 10 0 4 Direct reclaim write file sync I/O 0 0 0 0 Direct reclaim write anon sync I/O 0 0 0 0 Wake kswapd requests 392119 1201712 571935 571921 Kswapd wakeups 3 2 3 3 Kswapd pages scanned 4601307 4128076 3912317 3377165 Kswapd pages reclaimed 2432523 2318797 2312673 2144616 Kswapd reclaim write file async I/O 20 1 1 1 Kswapd reclaim write anon async I/O 57 132 11 121 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 6.19 7.30 13.04 10.88 Time kswapd awake (seconds) 21.73 26.51 25.55 23.90 Total pages scanned 5231132 5091890 4976255 5089100 Total pages reclaimed 2508073 2561335 2463577 2532263 %age total pages scanned/reclaimed 47.95% 50.30% 49.51% 49.76% %age total pages scanned/written 0.00% 0.00% 0.00% 0.00% %age file pages scanned/written 0.00% 0.00% 0.00% 0.00% Percentage Time Spent Direct Reclaim 18.89% 20.65% 32.65% 27.65% Percentage Time kswapd Awake 72.39% 80.68% 78.21% 77.40% Again, a similar trend that the congestion_wait changes mean that direct reclaim scans more pages but the overall number of pages scanned while slightly reduced, are very similar. The ratio of scanning/reclaimed remains roughly similar. The downside is that kswapd and direct reclaim was awake longer and for a larger percentage of the overall workload. It's possible there were big differences in the amount of time spent reclaiming slab pages between the different kernels which is plausible considering that the micro tests runs after fsmark and sysbench. Trace Reclaim Statistics: congestion_wait Direct number congest waited 845 1312 104 0 Direct time congest waited 19416ms 26560ms 7544ms 0ms Direct full congest waited 745 1105 72 0 Direct number conditional waited 0 0 1322 2935 Direct time conditional waited 0ms 0ms 12ms 312ms Direct full conditional waited 0 0 0 3 KSwapd number congest waited 39 102 75 63 KSwapd time congest waited 2484ms 6760ms 5756ms 3716ms KSwapd full congest waited 20 48 46 25 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 The vanilla kernel spent 20 seconds asleep in direct reclaim and only 312ms asleep with the patches. The time kswapd spent congest waited was also reduced by a large factor. MMTests Statistics: duration ser/Sys Time Running Test (seconds) 26.58 28.05 26.9 28.47 Total Elapsed Time (seconds) 30.02 32.86 32.67 30.88 With all patches applies, the completion times are very similar. X86-64 STRESS-HIGHALLOC traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Pass 1 82.00 ( 0.00%) 84.00 ( 2.00%) 85.00 ( 3.00%) 85.00 ( 3.00%) Pass 2 90.00 ( 0.00%) 87.00 (-3.00%) 88.00 (-2.00%) 89.00 (-1.00%) At Rest 92.00 ( 0.00%) 90.00 (-2.00%) 90.00 (-2.00%) 91.00 (-1.00%) Success figures across the board are broadly similar. traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Direct reclaims 1045 944 886 887 Direct reclaim pages scanned 135091 119604 109382 101019 Direct reclaim pages reclaimed 88599 47535 47863 46671 Direct reclaim write file async I/O 494 283 465 280 Direct reclaim write anon async I/O 29357 13710 16656 13462 Direct reclaim write file sync I/O 154 2 2 3 Direct reclaim write anon sync I/O 14594 571 509 561 Wake kswapd requests 7491 933 872 892 Kswapd wakeups 814 778 731 780 Kswapd pages scanned 7290822 15341158 11916436 13703442 Kswapd pages reclaimed 3587336 3142496 3094392 3187151 Kswapd reclaim write file async I/O 91975 32317 28022 29628 Kswapd reclaim write anon async I/O 1992022 789307 829745 849769 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 4588.93 2467.16 2495.41 2547.07 Time kswapd awake (seconds) 2497.66 1020.16 1098.06 1176.82 Total pages scanned 7425913 15460762 12025818 13804461 Total pages reclaimed 3675935 3190031 3142255 3233822 %age total pages scanned/reclaimed 49.50% 20.63% 26.13% 23.43% %age total pages scanned/written 28.66% 5.41% 7.28% 6.47% %age file pages scanned/written 1.25% 0.21% 0.24% 0.22% Percentage Time Spent Direct Reclaim 57.33% 42.15% 42.41% 42.99% Percentage Time kswapd Awake 43.56% 27.87% 29.76% 31.25% Scanned/reclaimed ratios again look good with big improvements in efficiency. The Scanned/written ratios also look much improved. With a better scanned/written ration, there is an expectation that IO would be more efficient and indeed, the time spent in direct reclaim is much reduced by the full series and kswapd spends a little less time awake. Overall, indications here are that allocations were happening much faster and this can be seen with a graph of the latency figures as the allocations were taking place http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-hydra-mean.ps FTrace Reclaim Statistics: congestion_wait Direct number congest waited 1333 204 169 4 Direct time congest waited 78896ms 8288ms 7260ms 200ms Direct full congest waited 756 92 69 2 Direct number conditional waited 0 0 26 186 Direct time conditional waited 0ms 0ms 0ms 2504ms Direct full conditional waited 0 0 0 25 KSwapd number congest waited 4 395 227 282 KSwapd time congest waited 384ms 25136ms 10508ms 18380ms KSwapd full congest waited 3 232 98 176 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 KSwapd full conditional waited 318 0 312 9 Overall, the time spent speeping is reduced. kswapd is still hitting congestion_wait() but that is because there are callers remaining where it wasn't clear in advance if they should be changed to wait_iff_congested() or not. Overall the sleep imes are reduced though - from 79ish seconds to about 19. MMTests Statistics: duration User/Sys Time Running Test (seconds) 3415.43 3386.65 3388.39 3377.5 Total Elapsed Time (seconds) 5733.48 3660.33 3689.41 3765.39 With the full series, the time to complete the tests are reduced by 30% PPC64 STRESS-HIGHALLOC traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Pass 1 17.00 ( 0.00%) 34.00 (17.00%) 38.00 (21.00%) 43.00 (26.00%) Pass 2 25.00 ( 0.00%) 37.00 (12.00%) 42.00 (17.00%) 46.00 (21.00%) At Rest 49.00 ( 0.00%) 43.00 (-6.00%) 45.00 (-4.00%) 51.00 ( 2.00%) Success rates there are *way* up particularly considering that the 16MB huge pages on PPC64 mean that it's always much harder to allocate them. FTrace Reclaim Statistics: vmscan stress-highalloc stress-highalloc stress-highalloc stress-highalloc traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4 Direct reclaims 499 505 564 509 Direct reclaim pages scanned 223478 41898 51818 45605 Direct reclaim pages reclaimed 137730 21148 27161 23455 Direct reclaim write file async I/O 399 136 162 136 Direct reclaim write anon async I/O 46977 2865 4686 3998 Direct reclaim write file sync I/O 29 0 1 3 Direct reclaim write anon sync I/O 31023 159 237 239 Wake kswapd requests 420 351 360 326 Kswapd wakeups 185 294 249 277 Kswapd pages scanned 15703488 16392500 17821724 17598737 Kswapd pages reclaimed 5808466 2908858 3139386 3145435 Kswapd reclaim write file async I/O 159938 18400 18717 13473 Kswapd reclaim write anon async I/O 3467554 228957 322799 234278 Kswapd reclaim write file sync I/O 0 0 0 0 Kswapd reclaim write anon sync I/O 0 0 0 0 Time stalled direct reclaim (seconds) 9665.35 1707.81 2374.32 1871.23 Time kswapd awake (seconds) 9401.21 1367.86 1951.75 1328.88 Total pages scanned 15926966 16434398 17873542 17644342 Total pages reclaimed 5946196 2930006 3166547 3168890 %age total pages scanned/reclaimed 37.33% 17.83% 17.72% 17.96% %age total pages scanned/written 23.27% 1.52% 1.94% 1.43% %age file pages scanned/written 1.01% 0.11% 0.11% 0.08% Percentage Time Spent Direct Reclaim 44.55% 35.10% 41.42% 36.91% Percentage Time kswapd Awake 86.71% 43.58% 52.67% 41.14% While the scanning rates are slightly up, the scanned/reclaimed and scanned/written figures are much improved. The time spent in direct reclaim and with kswapd are massively reduced, mostly by the lowlumpy patches. FTrace Reclaim Statistics: congestion_wait Direct number congest waited 725 303 126 3 Direct time congest waited 45524ms 9180ms 5936ms 300ms Direct full congest waited 487 190 52 3 Direct number conditional waited 0 0 200 301 Direct time conditional waited 0ms 0ms 0ms 1904ms Direct full conditional waited 0 0 0 19 KSwapd number congest waited 0 2 23 4 KSwapd time congest waited 0ms 200ms 420ms 404ms KSwapd full congest waited 0 2 2 4 KSwapd number conditional waited 0 0 0 0 KSwapd time conditional waited 0ms 0ms 0ms 0ms KSwapd full conditional waited 0 0 0 0 Not as dramatic a story here but the time spent asleep is reduced and we can still see what wait_iff_congested is going to sleep when necessary. MMTests Statistics: duration User/Sys Time Running Test (seconds) 12028.09 3157.17 3357.79 3199.16 Total Elapsed Time (seconds) 10842.07 3138.72 3705.54 3229.85 The time to complete this test goes way down. With the full series, we are allocating over twice the number of huge pages in 30% of the time and there is a corresponding impact on the allocation latency graph available at. http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-powyah-mean.ps This patch: Add a trace event for shrink_inactive_list() and updates the sample postprocessing script appropriately. It can be used to determine how many pages were reclaimed and for non-lumpy reclaim where exactly the pages were reclaimed from. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09vmscan: tracing: add a postprocessing script for reclaim-related ftrace eventsMel Gorman
Add a simple post-processing script for the reclaim-related trace events. It can be used to give an indication of how much traffic there is on the LRU lists and how severe latencies due to reclaim are. Example output looks like the following Reclaim latencies expressed as order-latency_in_ms uname-3942 9-200.179000000004 9-98.7900000000373 9-99.8330000001006 kswapd0-311 0-662.097999999998 0-2.79700000002049 \ 0-149.100000000035 0-3295.73600000003 0-9806.31799999997 0-35528.833 \ 0-10043.197 0-129740.979 0-3.50500000000466 0-3.54899999999907 \ 0-9297.78999999992 0-3.48499999998603 0-3596.97999999998 0-3.92799999995623 \ 0-3.35000000009313 0-16729.017 0-3.57799999997951 0-47435.0630000001 \ 0-3.7819999998901 0-5864.06999999995 0-18635.334 0-10541.289 9-186011.565 \ 9-3680.86300000001 9-1379.06499999994 9-958571.115 9-66215.474 \ 9-6721.14699999988 9-1962.15299999993 9-1094806.125 9-2267.83199999994 \ 9-47120.9029999999 9-427653.886 9-2.6359999999404 9-632.148999999976 \ 9-476.753000000026 9-495.577000000048 9-8.45900000003166 9-6.6820000000298 \ 9-1.30500000016764 9-251.746000000043 9-383.905000000028 9-80.1419999999925 \ 9-281.160000000149 9-14.8780000000261 9-381.45299999998 9-512.07799999998 \ 9-49.5519999999087 9-167.439000000013 9-183.820999999996 9-239.527999999933 \ 9-19.9479999998584 9-148.747999999905 9-164.583000000101 9-16.9480000000913 \ 9-192.376000000164 9-64.1010000000242 9-1.40800000005402 9-3.60800000000745 \ 9-17.1359999999404 9-4.69500000006519 9-2.06400000001304 9-1582488.554 \ 9-6244.19499999983 9-348153.812 9-2.0999999998603 9-0.987999999895692 \ 0-32218.473 0-1.6140000000596 0-1.28100000019185 0-1.41300000017509 \ 0-1.32299999985844 0-602.584000000032 0-1.34400000004098 0-1.6929999999702 \ 1-22101.8190000001 9-174876.724 9-16.2420000000857 9-175.165999999736 \ 9-15.8589999997057 9-0.604999999981374 9-3061.09000000032 9-479.277000000235 \ 9-1.54499999992549 9-771.985000000335 9-4.88700000010431 9-15.0649999999441 \ 9-0.879999999888241 9-252.01500000013 9-1381.03600000031 9-545.689999999944 \ 9-3438.0129999998 9-3343.70099999988 bench-stresshig-3942 9-7063.33900000004 9-129960.482 9-2062.27500000002 \ 9-3845.59399999992 9-171.82799999998 9-16493.821 9-7615.23900000006 \ 9-10217.848 9-983.138000000035 9-2698.39999999991 9-4016.1540000001 \ 9-5522.37700000009 9-21630.429 \ 9-15061.048 9-10327.953 9-542.69700000016 9-317.652000000002 \ 9-8554.71699999995 9-1786.61599999992 9-1899.31499999994 9-2093.41899999999 \ 9-4992.62400000007 9-942.648999999976 9-1923.98300000001 9-3.7980000001844 \ 9-5.99899999983609 9-0.912000000011176 9-1603.67700000014 9-1.98300000000745 \ 9-3.96500000008382 9-0.902999999932945 9-2802.72199999983 9-1078.24799999991 \ 9-2155.82900000014 9-10.058999999892 9-1984.723 9-1687.97999999998 \ 9-1136.05300000007 9-3183.61699999985 9-458.731000000145 9-6.48600000003353 \ 9-1013.25200000009 9-8415.22799999989 9-10065.584 9-2076.79600000009 \ 9-3792.65699999989 9-71.2010000001173 9-2560.96999999997 9-2260.68400000012 \ 9-2862.65799999982 9-1255.81500000018 9-15.7440000001807 9-4.33499999996275 \ 9-1446.63800000004 9-238.635000000009 9-60.1790000000037 9-4.38800000003539 \ 9-639.567000000039 9-306.698000000091 9-31.4070000001229 9-74.997999999905 \ 9-632.725999999791 9-1625.93200000003 9-931.266000000061 9-98.7749999999069 \ 9-984.606999999844 9-225.638999999966 9-421.316000000108 9-653.744999999879 \ 9-572.804000000004 9-769.158999999985 9-603.918000000063 9-4.28499999991618 \ 9-626.21399999992 9-1721.25 9-0.854999999981374 9-572.39599999995 \ 9-681.881999999983 9-1345.12599999993 9-363.666999999899 9-3823.31099999999 \ 9-2991.28200000012 9-4.27099999994971 9-309.76500000013 9-3068.35700000008 \ 9-788.25 9-3515.73999999999 9-2065.96100000013 9-286.719999999972 \ 9-316.076000000117 9-344.151000000071 9-2.51000000000931 9-306.688000000082 \ 9-1515.00099999993 9-336.528999999864 9-793.491999999853 9-457.348999999929 \ 9-13620.155 9-119.933999999892 9-35.0670000000391 9-918.266999999993 \ 9-828.569000000134 9-4863.81099999999 9-105.222000000067 9-894.23900000006 \ 9-110.964999999851 9-0.662999999942258 9-12753.3150000002 9-12.6129999998957 \ 9-13368.0899999999 9-12.4199999999255 9-1.00300000002608 9-1.41100000008009 \ 9-10300.5290000001 9-16.502000000095 9-30.7949999999255 9-6283.0140000002 \ 9-4320.53799999994 9-6826.27300000004 9-3.07299999985844 9-1497.26799999992 \ 9-13.4040000000969 9-3.12999999988824 9-3.86100000003353 9-11.3539999998175 \ 9-0.10799999977462 9-21.780999999959 9-209.695999999996 9-299.647000000114 \ 9-6.01699999999255 9-20.8349999999627 9-22.5470000000205 9-5470.16800000006 \ 9-7.60499999998137 9-0.821000000229105 9-1.56600000010803 9-14.1669999998994 \ 9-0.209000000031665 9-1.82300000009127 9-1.70000000018626 9-19.9429999999702 \ 9-124.266999999993 9-0.0389999998733401 9-6.71400000015274 9-16.7710000001825 \ 9-31.0409999999683 9-0.516999999992549 9-115.888000000035 9-5.19900000002235 \ 9-222.389999999898 9-11.2739999999758 9-80.9050000000279 9-8.14500000001863 \ 9-4.44599999999627 9-0.218999999808148 9-0.715000000083819 9-0.233000000007451 \ 9-48.2630000000354 9-248.560999999987 9-374.96800000011 9-644.179000000004 \ 9-0.835999999893829 9-79.0060000000522 9-128.447999999858 9-0.692000000039116 \ 9-5.26500000013039 9-128.449000000022 9-2.04799999995157 9-12.0990000001621 \ 9-8.39899999997579 9-10.3860000001732 9-11.9310000000987 9-53.4450000000652 \ 9-0.46999999997206 9-2.96299999998882 9-17.9699999999721 9-0.776000000070781 \ 9-25.2919999998994 9-33.1110000000335 9-0.434000000124797 9-0.641000000061467 \ 9-0.505000000121072 9-1.12800000002608 9-149.222000000067 9-1.17599999997765 \ 9-3247.33100000001 9-10.7439999999478 9-153.523000000045 9-1.38300000014715 \ 9-794.762000000104 9-3.36199999996461 9-128.765999999829 9-181.543999999994 \ 9-78149.8229999999 9-176.496999999974 9-89.9940000001807 9-9.12700000009499 \ 9-250.827000000048 9-0.224999999860302 9-0.388999999966472 9-1.16700000036508 \ 9-32.1740000001155 9-12.6800000001676 9-0.0720000001601875 9-0.274999999906868 \ 9-0.724000000394881 9-266.866000000387 9-45.5709999999963 9-4.54399999976158 \ 9-8.27199999988079 9-4.38099999958649 9-0.512000000104308 9-0.0640000002458692 \ 9-5.20000000018626 9-0.0839999997988343 9-12.816000000108 9-0.503000000026077 \ 9-0.507999999914318 9-6.23999999975786 9-3.35100000025705 9-18.8530000001192 \ 9-25.2220000000671 9-68.2309999996796 9-98.9939999999478 9-0.441000000108033 \ 9-4.24599999981001 9-261.702000000048 9-3.01599999982864 9-0.0749999997206032 \ 9-0.0370000000111759 9-4.375 9-3.21800000034273 9-11.3960000001825 \ 9-0.0540000000037253 9-0.286000000312924 9-0.865999999921769 \ 9-0.294999999925494 9-6.45999999996275 9-4.31099999975413 9-128.248999999836 \ 9-0.282999999821186 9-102.155000000261 9-0.0860000001266599 \ 9-0.0540000000037253 9-0.935000000055879 9-0.0670000002719462 \ 9-5.8640000000596 9-19.9860000000335 9-4.18699999991804 9-0.566000000108033 \ 9-2.55099999997765 9-0.702000000048429 9-131.653999999631 9-0.638999999966472 \ 9-14.3229999998584 9-183.398000000045 9-178.095999999903 9-3.22899999981746 \ 9-7.31399999978021 9-22.2400000002235 9-11.7979999999516 9-108.10599999968 \ 9-99.0159999998286 9-102.640999999829 9-38.414000000339 Process Direct Wokeup Pages Pages Pages details Rclms Kswapd Scanned Sync-IO ASync-IO cc1-30800 0 1 0 0 0 wakeup-0=1 cc1-24260 0 1 0 0 0 wakeup-0=1 cc1-24152 0 12 0 0 0 wakeup-0=12 cc1-8139 0 1 0 0 0 wakeup-0=1 cc1-4390 0 1 0 0 0 wakeup-0=1 cc1-4648 0 7 0 0 0 wakeup-0=7 cc1-4552 0 3 0 0 0 wakeup-0=3 dd-4550 0 31 0 0 0 wakeup-0=31 date-4898 0 1 0 0 0 wakeup-0=1 cc1-6549 0 7 0 0 0 wakeup-0=7 as-22202 0 17 0 0 0 wakeup-0=17 cc1-6495 0 9 0 0 0 wakeup-0=9 cc1-8299 0 1 0 0 0 wakeup-0=1 cc1-6009 0 1 0 0 0 wakeup-0=1 cc1-2574 0 2 0 0 0 wakeup-0=2 cc1-30568 0 1 0 0 0 wakeup-0=1 cc1-2679 0 6 0 0 0 wakeup-0=6 sh-13747 0 12 0 0 0 wakeup-0=12 cc1-22193 0 18 0 0 0 wakeup-0=18 cc1-30725 0 2 0 0 0 wakeup-0=2 as-4392 0 2 0 0 0 wakeup-0=2 cc1-28180 0 14 0 0 0 wakeup-0=14 cc1-13697 0 2 0 0 0 wakeup-0=2 cc1-22207 0 8 0 0 0 wakeup-0=8 cc1-15270 0 179 0 0 0 wakeup-0=179 cc1-22011 0 82 0 0 0 wakeup-0=82 cp-14682 0 1 0 0 0 wakeup-0=1 as-11926 0 2 0 0 0 wakeup-0=2 cc1-6016 0 5 0 0 0 wakeup-0=5 make-18554 0 13 0 0 0 wakeup-0=13 cc1-8292 0 12 0 0 0 wakeup-0=12 make-24381 0 1 0 0 0 wakeup-1=1 date-18681 0 33 0 0 0 wakeup-0=33 cc1-32276 0 1 0 0 0 wakeup-0=1 timestamp-outpu-2809 0 253 0 0 0 wakeup-0=240 wakeup-1=13 date-18624 0 7 0 0 0 wakeup-0=7 cc1-30960 0 9 0 0 0 wakeup-0=9 cc1-4014 0 1 0 0 0 wakeup-0=1 cc1-30706 0 22 0 0 0 wakeup-0=22 uname-3942 4 1 306 0 17 direct-9=4 wakeup-9=1 cc1-28207 0 1 0 0 0 wakeup-0=1 cc1-30563 0 9 0 0 0 wakeup-0=9 cc1-22214 0 10 0 0 0 wakeup-0=10 cc1-28221 0 11 0 0 0 wakeup-0=11 cc1-28123 0 6 0 0 0 wakeup-0=6 kswapd0-311 0 7 357302 0 34233 wakeup-0=7 cc1-5988 0 7 0 0 0 wakeup-0=7 as-30734 0 161 0 0 0 wakeup-0=161 cc1-22004 0 45 0 0 0 wakeup-0=45 date-4590 0 4 0 0 0 wakeup-0=4 cc1-15279 0 213 0 0 0 wakeup-0=213 date-30735 0 1 0 0 0 wakeup-0=1 cc1-30583 0 4 0 0 0 wakeup-0=4 cc1-32324 0 2 0 0 0 wakeup-0=2 cc1-23933 0 3 0 0 0 wakeup-0=3 cc1-22001 0 36 0 0 0 wakeup-0=36 bench-stresshig-3942 287 287 80186 6295 12196 direct-9=287 wakeup-9=287 cc1-28170 0 7 0 0 0 wakeup-0=7 date-7932 0 92 0 0 0 wakeup-0=92 cc1-22222 0 6 0 0 0 wakeup-0=6 cc1-32334 0 16 0 0 0 wakeup-0=16 cc1-2690 0 6 0 0 0 wakeup-0=6 cc1-30733 0 9 0 0 0 wakeup-0=9 cc1-32298 0 2 0 0 0 wakeup-0=2 cc1-13743 0 18 0 0 0 wakeup-0=18 cc1-22186 0 4 0 0 0 wakeup-0=4 cc1-28214 0 11 0 0 0 wakeup-0=11 cc1-13735 0 1 0 0 0 wakeup-0=1 updatedb-8173 0 18 0 0 0 wakeup-0=18 cc1-13750 0 3 0 0 0 wakeup-0=3 cat-2808 0 2 0 0 0 wakeup-0=2 cc1-15277 0 169 0 0 0 wakeup-0=169 date-18317 0 1 0 0 0 wakeup-0=1 cc1-15274 0 197 0 0 0 wakeup-0=197 cc1-30732 0 1 0 0 0 wakeup-0=1 Kswapd Kswapd Order Pages Pages Pages Instance Wakeups Re-wakeup Scanned Sync-IO ASync-IO kswapd0-311 91 24 357302 0 34233 wake-0=31 wake-1=1 wake-9=59 rewake-0=10 rewake-1=1 rewake-9=13 Summary Direct reclaims: 291 Direct reclaim pages scanned: 437794 Direct reclaim write sync I/O: 6295 Direct reclaim write async I/O: 46446 Wake kswapd requests: 2152 Time stalled direct reclaim: 519.163009000002 ms Kswapd wakeups: 91 Kswapd pages scanned: 357302 Kswapd reclaim write sync I/O: 0 Kswapd reclaim write async I/O: 34233 Time kswapd awake: 5282.749757 ms Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Larry Woodman <lwoodman@redhat.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michael Rubin <mrubin@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-21tracing/documentation: Document dynamic ftracer internalsMike Frysinger
Add more details to the dynamic function tracing design implementation. Signed-off-by: Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1279610015-10250-1-git-send-email-vapier@gentoo.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-07-05tracing/kprobes: Support "string" typeMasami Hiramatsu
Support string type tracing and printing in kprobe-tracer. This allows user to trace string data in kernel including __user data. Note that sometimes __user data may not be accessed if it is paged-out (sorry, but kprobes operation should be done in atomic, we can not wait for page-in). Commiter note: Fixed up conflicts with b7e2ece. Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20100519195724.2885.18788.stgit@localhost6.localdomain6> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-06-09tracing: Remove kmemtrace ftrace pluginLi Zefan
We have been resisting new ftrace plugins and removing existing ones, and kmemtrace has been superseded by kmem trace events and perf-kmem, so we remove it. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> [ remove kmemtrace from the makefile, handle slob too ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-05-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits) vlynq: make whole Kconfig-menu dependant on architecture add descriptive comment for TIF_MEMDIE task flag declaration. EEPROM: max6875: Header file cleanup EEPROM: 93cx6: Header file cleanup EEPROM: Header file cleanup agp: use NULL instead of 0 when pointer is needed rtc-v3020: make bitfield unsigned PCI: make bitfield unsigned jbd2: use NULL instead of 0 when pointer is needed cciss: fix shadows sparse warning doc: inode uses a mutex instead of a semaphore. uml: i386: Avoid redefinition of NR_syscalls fix "seperate" typos in comments cocbalt_lcdfb: correct sections doc: Change urls for sparse Powerpc: wii: Fix typo in comment i2o: cleanup some exit paths Documentation/: it's -> its where appropriate UML: Fix compiler warning due to missing task_struct declaration UML: add kernel.h include to signal.c ...
2010-05-18Merge branch 'tracing-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Fix "integer as NULL pointer" warning. tracing: Fix tracepoint.h DECLARE_TRACE() to allow more than one header tracing: Make the documentation clear on trace_event boot option ring-buffer: Wrap open-coded WARN_ONCE tracing: Convert nop macros to static inlines tracing: Fix sleep time function profiling tracing: Show sample std dev in function profiling tracing: Add documentation for trace commands mod, traceon/traceoff ring-buffer: Make benchmark handle missed events ring-buffer: Make non-consuming read less expensive with lots of cpus. tracing: Add graph output support for irqsoff tracer tracing: Have graph flags passed in to ouput functions tracing: Add ftrace events for graph tracer tracing: Dump either the oops's cpu source or all cpus buffers tracing: Fix uninitialized variable of tracing/trace output
2010-05-04tracing: Make the documentation clear on trace_event boot optionLi Zefan
Make it clear that event-list is a comma separated list of events. Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4B2F154C.2060503@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-27tracing: Add documentation for trace commands mod, traceon/traceoffChase Douglas
The mod command went in as commit 64e7c440618998fd69eee6ab490b042d12248021 The traceon/traceoff commands went in as commit 23b4ff3aa479c9e3bb23cb6b2d0a97878399784a Signed-off-by: Chase Douglas <chase.douglas@canonical.com> LKML-Reference: <1272045759-32018-1-git-send-email-chase.douglas@canonical.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-21tracing: Dump either the oops's cpu source or all cpus buffersFrederic Weisbecker
The ftrace_dump_on_oops kernel parameter, sysctl and sysrq let one dump every cpu buffers when an oops or panic happens. It's nice when you have few cpus but it may take ages if have many, plus you miss the real origin of the problem in all the cpu traces. Sometimes, all you need is to dump the cpu buffer that triggered the opps, most of the time it is our main interest. This patch modifies ftrace_dump_on_oops to handle this choice. The ftrace_dump_on_oops kernel parameter, when it comes alone, has the same behaviour than before. But ftrace_dump_on_oops=orig_cpu will only dump the buffer of the cpu that oops'ed. Similarly, sysctl kernel.ftrace_dump_on_oops=1 and echo 1 > /proc/sys/kernel/ftrace_dump_on_oops keep their previous behaviour. But setting 2 jumps into cpu origin dump mode. v2: Fix double setup v3: Fix spelling issues reported by Randy Dunlap v4: Also update __ftrace_dump in the selftests Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
2010-04-14tracing/kprobes: Support basic types on dynamic eventsMasami Hiramatsu
Support basic types of integer (u8, u16, u32, u64, s8, s16, s32, s64) in kprobe tracer. With this patch, users can specify above basic types on each arguments after ':'. If omitted, the argument type is set as unsigned long (u32 or u64, arch-dependent). e.g. echo 'p account_system_time+0 hardirq_offset=%si:s32' > kprobe_events adds a probe recording hardirq_offset in signed-32bits value on the entry of account_system_time. Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20100412171708.3790.18599.stgit@localhost6.localdomain6> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-03-16Fix typos in commentsThomas Weber
[Ss]ytem => [Ss]ystem udpate => update paramters => parameters orginal => original Signed-off-by: Thomas Weber <swirl@gmx.li> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-08Merge branch 'for-next' into for-linusJiri Kosina
Conflicts: Documentation/filesystems/proc.txt arch/arm/mach-u300/include/mach/debug-macro.S drivers/net/qlge/qlge_ethtool.c drivers/net/qlge/qlge_main.c drivers/net/typhoon.c
2010-02-28Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (172 commits) perf_event, amd: Fix spinlock initialization perf_event: Fix preempt warning in perf_clock() perf tools: Flush maps on COMM events perf_events, x86: Split PMU definitions into separate files perf annotate: Handle samples not at objdump output addr boundaries perf_events, x86: Remove superflous MSR writes perf_events: Simplify code by removing cpu argument to hw_perf_group_sched_in() perf_events, x86: AMD event scheduling perf_events: Add new start/stop PMU callbacks perf_events: Report the MMAP pgoff value in bytes perf annotate: Defer allocating sym_priv->hist array perf symbols: Improve debugging information about symtab origins perf top: Use a macro instead of a constant variable perf symbols: Check the right return variable perf/scripts: Tag syscall_name helper as not yet available perf/scripts: Add perf-trace-python Documentation perf/scripts: Remove unnecessary PyTuple resizes perf/scripts: Add syscall tracing scripts perf/scripts: Add Python scripting engine perf/scripts: Remove check-perf-trace from listed scripts ... Fix trivial conflict in tools/perf/util/probe-event.c
2010-02-27Merge branch 'tracing/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core
2010-02-17tracing: Unify arch_syscall_addr() implementationsMike Frysinger
Most implementations of arch_syscall_addr() are the same, so create a default version in common code and move the one piece that differs (the syscall table) to asm/syscall.h. New arch ports don't have to waste time copying & pasting this simple function. The s390/sparc versions need to be different, so document why. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1264498803-17278-1-git-send-email-vapier@gentoo.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-02-09tree-wide: Assorted spelling fixesDaniel Mack
In particular, several occurances of funny versions of 'success', 'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address', 'beginning', 'desirable', 'separate' and 'necessary' are fixed. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Joe Perches <joe@perches.com> Cc: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-01-26tracing/documentation: Cover new frame pointer semanticsMike Frysinger
Update the graph tracer examples to cover the new frame pointer semantics (in terms of passing it along). Move the HAVE_FUNCTION_GRAPH_FP_TEST docs out of the Kconfig, into the right place, and expand on the details. Signed-off-by: Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1264165967-18938-1-git-send-email-vapier@gentoo.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-01-26tracing/documentation: Fix a typo in ftrace.txtYang Hongyang
'ftrace' is no longer the name of the function tracer, to activate the function trace 'echo function > current_tracer' is to be used instead of 'echo ftrace > current_tracer'. Update the documentation to reflect the current implementation. Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com> LKML-Reference: <4B5D0BA8.20106@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-01-20kprobetrace, doc: Add the explanation to remove probe pointsMotohiro KOSAKI
Latest kprobetrace can remove probe points selectively, thus the documentation should be updated too. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20100119023512.31880.35535.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-20kprobetrace, doc: Shell needs single quote to use $ characterMotohiro KOSAKI
Shell interprets $val as shell variable, thus we need quote if we use the echo command. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20100119023505.31880.17367.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13tracing/kprobe: Drop function argument access syntaxMasami Hiramatsu
Drop function argument access syntax, because the function arguments depend on not only architecture but also compile-options and function API. And now, we have perf-probe for finding register/memory assigned to each argument. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Neuling <mikey@neuling.org> Cc: linuxppc-dev@ozlabs.org LKML-Reference: <20100105224648.19431.52309.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13tracing/kprobe: Update example output in documentationMasami Hiramatsu
Update example output in documentation according to current implementation. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20100105224641.19431.34967.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-11Documentation: update ring-buffer-design.txtRandy Dunlap
Fix typos, grammos, spellos, hyphenation. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-31Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Fix sign fields in ftrace_define_fields_##call() tracing/syscalls: Fix typo in SYSCALL_DEFINE0 tracing/kprobe: Show sign of fields in trace_kprobe format files ksym_tracer: Remove trace_stat ksym_tracer: Fix race when incrementing count ksym_tracer: Fix to allow writing newline to ksym_trace_filter ksym_tracer: Fix to make the tracer work tracing: Kconfig spelling fixes and cleanups tracing: Fix setting tracer specific options Documentation: Update ftrace-design.txt Documentation: Update tracepoint-analysis.txt Documentation: Update mmiotrace.txt
2009-12-22mm tracing: cleanup Documentation/trace/events-kmem.txtRandy Dunlap
Clean up typos/grammos/spellos in events-kmem.txt. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-20Documentation: Update ftrace-design.txtRandy Dunlap
Correct grammos. Spell out words. Add missing words. Consistent use of "mcount()" function name. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <4B2C0D78.6060707@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-20Documentation: Update tracepoint-analysis.txtRandy Dunlap
Fix grammar, spelling, punctuation, hyphenation, section numbering. Tell what PCL means. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <4B2C0D70.4030707@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-20Documentation: Update mmiotrace.txtRandy Dunlap
Fix typos, spellos, hyphenation, line lengths. BTW: are there some userspace tools? There is a reference to some at the wiki page, but there are no tools listed there. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Pekka Paalanen <pq@iki.fi> LKML-Reference: <4B2C0D68.6080401@oracle.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-17Merge branch 'perf/core' into perf/probesIngo Molnar
Resolved merge conflict in tools/perf/Makefile Merge reason: we want to queue up a dependent patch. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-04tracing/kprobes: Rename Kprobe-tracer to kprobe-eventMasami Hiramatsu
Rename Kprobes-based event tracer to kprobes-based tracing event (kprobe-event), since it is not a tracer but an extensible tracing event interface. This also changes CONFIG_KPROBE_TRACER to CONFIG_KPROBE_EVENT and sets it y by default. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Frank Ch. Eigler <fche@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> LKML-Reference: <20091104001247.3454.14131.stgit@harusame> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-04Merge commit 'v2.6.32-rc6' into perf/coreIngo Molnar
Conflicts: tools/perf/Makefile Merge reason: Resolve the conflict, merge to upstream and merge in perf fixes so we can add a dependent patch. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-24tracing: Fix comment typo and documentation exampleJiri Olsa
Trivial patch to fix a documentation example and to fix a comment. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091023233646.871719877@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-23Merge branch 'perf/core' into perf/probesIngo Molnar
Conflicts: tools/perf/Makefile Merge reason: - fix the conflict - pick up the pr_*() infrastructure to queue up dependent patch Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14tracing: Document HAVE_SYSCALL_TRACEPOINTS needsFrederic Weisbecker
Document the arch needed requirements to get the support for syscalls tracing. v2: HAVE_FTRACE_SYSCALLS have been changed to HAVE_SYSCALL_TRACEPOINTS recently. Update this config name in the documentation then. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org>
2009-10-12tracing/kprobes: Make special variable names more self-explainableMasami Hiramatsu
Rename special variables to more self-explainable names as below: - $rv to $retval - $sa to $stack - $aN to $argN - $sN to $stackN Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Frank Ch. Eigler <fche@redhat.com> LKML-Reference: <20091007222759.1684.3319.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-10-12tracing/kprobes: Remove '$ra' special variableMasami Hiramatsu
Remove '$ra' (return address) because it is already shown at the head of each entry. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Frank Ch. Eigler <fche@redhat.com> LKML-Reference: <20091007222748.1684.12711.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-10-12tracing/kprobes: Add $ prefix to special variablesMasami Hiramatsu
Add $ prefix to the special variables(e.g. sa, rv) of kprobe-tracer. This resolves consistency issues between kprobe_events and perf-kprobe. The main goal is to avoid conflicts between local variable names of probed functions, used by perf probe, and special variables used in the kprobe event creation interface (stack values, etc...) and also available from perf probe. ie: we don't want rv (return value) to conflict with a local variable named rv in a probed function. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Frank Ch. Eigler <fche@redhat.com> LKML-Reference: <20091007222740.1684.91170.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-23Merge commit 'linus/master' into tracing/kprobesFrederic Weisbecker
Conflicts: kernel/trace/Makefile kernel/trace/trace.h kernel/trace/trace_event_types.h kernel/trace/trace_export.c Merge reason: Sync with latest significant tracing core changes.
2009-09-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits) trivial: fix typo in aic7xxx comment trivial: fix comment typo in drivers/ata/pata_hpt37x.c trivial: typo in kernel-parameters.txt trivial: fix typo in tracing documentation trivial: add __init/__exit macros in drivers/gpio/bt8xxgpio.c trivial: add __init macro/ fix of __exit macro location in ipmi_poweroff.c trivial: remove unnecessary semicolons trivial: Fix duplicated word "options" in comment trivial: kbuild: remove extraneous blank line after declaration of usage() trivial: improve help text for mm debug config options trivial: doc: hpfall: accept disk device to unload as argument trivial: doc: hpfall: reduce risk that hpfall can do harm trivial: SubmittingPatches: Fix reference to renumbered step trivial: fix typos "man[ae]g?ment" -> "management" trivial: media/video/cx88: add __init/__exit macros to cx88 drivers trivial: fix typo in CONFIG_DEBUG_FS in gcov doc trivial: fix missing printk space in amd_k7_smp_check trivial: fix typo s/ketymap/keymap/ in comment trivial: fix typo "to to" in multiple files trivial: fix typos in comments s/DGBU/DBGU/ ...
2009-09-22tracing, documentation: Add a document on the kmem tracepointsMel Gorman
Knowing tracepoints exist is not quite the same as knowing what they should be used for. This patch adds a document giving a basic description of the kmem tracepoints and why they might be useful to a performance analyst. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22tracing, documentation: add a document describing how to do some performance ↵Mel Gorman
analysis with tracepoints The documentation for ftrace, events and tracepoints is pretty extensive. Similarly, the perf PCL tools help files --help are there and the code simple enough to figure out what much of the switches mean. However, pulling the discrete bits and pieces together and translating that into "how do I solve a problem" requires a fair amount of imagination. This patch adds a simple document intended to get someone started on the Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22tracing, page-allocator: add a postprocessing script for ↵Mel Gorman
page-allocator-related ftrace events This patch adds a simple post-processing script for the page-allocator-related trace events. It can be used to give an indication of who the most allocator-intensive processes are and how often the zone lock was taken during the tracing period. Example output looks like Process Pages Pages Pages Pages PCPU PCPU PCPU Fragment Fragment MigType Fragment Fragment Unknown details allocd allocd freed freed pages drains refills Fallback Causing Changed Severe Moderate under lock direct pagevec drain swapper-0 0 0 2 0 0 0 0 0 0 0 0 0 0 Xorg-3770 10603 5952 3685 6978 5996 194 192 0 0 0 0 0 0 modprobe-21397 51 0 0 86 31 1 0 0 0 0 0 0 0 xchat-5370 228 93 0 0 0 0 3 0 0 0 0 0 0 awesome-4317 32 32 0 0 0 0 32 0 0 0 0 0 0 thinkfan-3863 2 0 1 1 0 0 0 0 0 0 0 0 0 hald-addon-stor-3935 2 0 0 0 0 0 0 0 0 0 0 0 0 akregator-4506 1 1 0 0 0 0 1 0 0 0 0 0 0 xmms-14888 0 0 1 0 0 0 0 0 0 0 0 0 0 khelper-12 1 0 0 0 0 0 0 0 0 0 0 0 0 Optionally, the output can include information on the parent or aggregate based on process name instead of aggregating based on each pid. Example output including parent information and stripped out the PID looks something like; Process Pages Pages Pages Pages PCPU PCPU PCPU Fragment Fragment MigType Fragment Fragment Unknown details allocd allocd freed freed pages drains refills Fallback Causing Changed Severe Moderate under lock direct pagevec drain gdm-3756 :: Xorg-3770 3796 2976 99 3813 3224 104 98 0 0 0 0 0 0 init-1 :: hald-3892 1 0 0 0 0 0 0 0 0 0 0 0 0 git-21447 :: editor-21448 4 0 4 0 0 0 0 0 0 0 0 0 0 This says that Xorg allocated 3796 pages and it's parent process is gdm with a PID of 3756; The postprocessor parses the text output of tracing. While there is a binary format, the expectation is that the binary output can be readily translated into text and post-processed offline. Obviously if the text format changes, the parser will break but the regular expression parser is fairly rudimentary so should be readily adjustable. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Reviewed-by: Ingo Molnar <mingo@elte.hu> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Li Ming Chun <macli@brc.ubc.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-21trivial: fix typo in tracing documentationMichal Sojka
Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21trivial: fix typos "man[ae]g?ment" -> "management"Uwe Kleine-Koenig
Signed-off-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-19tracing, perf: Convert the power tracer into an event tracerArjan van de Ven
This patch converts the existing power tracer into an event tracer, so that power events (C states and frequency changes) can be tracked via "perf". This also removes the perl script that was used to demo the tracer; its functionality is being replaced entirely with timechart. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20090912130542.6d314860@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>