Commit f51bdd2e97098a5cbb3cba7c3a56fa0e9ac3c444
Committed by
Linus Torvalds
Linus Torvalds
1 parent
7e8aa04898
Exists in
master
and in
6 other branches
mm: fix a vmscan warning
I get the below warning: BUG: using smp_processor_id() in preemptible [00000000] code: bash/746 caller is native_sched_clock+0x37/0x6e Pid: 746, comm: bash Tainted: G W 3.0.0+ #254 Call Trace: [<ffffffff813435c6>] debug_smp_processor_id+0xc2/0xdc [<ffffffff8104158d>] native_sched_clock+0x37/0x6e [<ffffffff81116219>] try_to_free_mem_cgroup_pages+0x7d/0x270 [<ffffffff8114f1f8>] mem_cgroup_force_empty+0x24b/0x27a [<ffffffff8114ff21>] ? sys_close+0x38/0x138 [<ffffffff8114ff21>] ? sys_close+0x38/0x138 [<ffffffff8114f257>] mem_cgroup_force_empty_write+0x17/0x19 [<ffffffff810c72fb>] cgroup_file_write+0xa8/0xba [<ffffffff811522d2>] vfs_write+0xb3/0x138 [<ffffffff8115241a>] sys_write+0x4a/0x71 [<ffffffff8114ffd9>] ? sys_close+0xf0/0x138 [<ffffffff8176deab>] system_call_fastpath+0x16/0x1b sched_clock() can't be used with preempt enabled. And we don't need fast approach to get clock here, so let's use ktime API. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Tested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 8 additions and 8 deletions Side-by-side Diff
mm/vmscan.c
| ... | ... | @@ -2283,7 +2283,7 @@ |
| 2283 | 2283 | .mem_cgroup = mem, |
| 2284 | 2284 | .memcg_record = rec, |
| 2285 | 2285 | }; |
| 2286 | - unsigned long start, end; | |
| 2286 | + ktime_t start, end; | |
| 2287 | 2287 | |
| 2288 | 2288 | sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) | |
| 2289 | 2289 | (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK); |
| ... | ... | @@ -2292,7 +2292,7 @@ |
| 2292 | 2292 | sc.may_writepage, |
| 2293 | 2293 | sc.gfp_mask); |
| 2294 | 2294 | |
| 2295 | - start = sched_clock(); | |
| 2295 | + start = ktime_get(); | |
| 2296 | 2296 | /* |
| 2297 | 2297 | * NOTE: Although we can get the priority field, using it |
| 2298 | 2298 | * here is not a good idea, since it limits the pages we can scan. |
| 2299 | 2299 | |
| ... | ... | @@ -2301,10 +2301,10 @@ |
| 2301 | 2301 | * the priority and make it zero. |
| 2302 | 2302 | */ |
| 2303 | 2303 | shrink_zone(0, zone, &sc); |
| 2304 | - end = sched_clock(); | |
| 2304 | + end = ktime_get(); | |
| 2305 | 2305 | |
| 2306 | 2306 | if (rec) |
| 2307 | - rec->elapsed += end - start; | |
| 2307 | + rec->elapsed += ktime_to_ns(ktime_sub(end, start)); | |
| 2308 | 2308 | *scanned = sc.nr_scanned; |
| 2309 | 2309 | |
| 2310 | 2310 | trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed); |
| ... | ... | @@ -2319,7 +2319,7 @@ |
| 2319 | 2319 | { |
| 2320 | 2320 | struct zonelist *zonelist; |
| 2321 | 2321 | unsigned long nr_reclaimed; |
| 2322 | - unsigned long start, end; | |
| 2322 | + ktime_t start, end; | |
| 2323 | 2323 | int nid; |
| 2324 | 2324 | struct scan_control sc = { |
| 2325 | 2325 | .may_writepage = !laptop_mode, |
| ... | ... | @@ -2337,7 +2337,7 @@ |
| 2337 | 2337 | .gfp_mask = sc.gfp_mask, |
| 2338 | 2338 | }; |
| 2339 | 2339 | |
| 2340 | - start = sched_clock(); | |
| 2340 | + start = ktime_get(); | |
| 2341 | 2341 | /* |
| 2342 | 2342 | * Unlike direct reclaim via alloc_pages(), memcg's reclaim doesn't |
| 2343 | 2343 | * take care of from where we get pages. So the node where we start the |
| 2344 | 2344 | |
| ... | ... | @@ -2352,9 +2352,9 @@ |
| 2352 | 2352 | sc.gfp_mask); |
| 2353 | 2353 | |
| 2354 | 2354 | nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink); |
| 2355 | - end = sched_clock(); | |
| 2355 | + end = ktime_get(); | |
| 2356 | 2356 | if (rec) |
| 2357 | - rec->elapsed += end - start; | |
| 2357 | + rec->elapsed += ktime_to_ns(ktime_sub(end, start)); | |
| 2358 | 2358 | |
| 2359 | 2359 | trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed); |
| 2360 | 2360 |