The patch titled mm: fix a vmscan warning has been added to the -mm tree. Its filename is mm-fix-a-vmscan-warning.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: fix a vmscan warning From: Shaohua Li <shaohua.li@xxxxxxxxx> I get below warnning: 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@xxxxxxxxx> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Tested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff -puN mm/vmscan.c~mm-fix-a-vmscan-warning mm/vmscan.c --- a/mm/vmscan.c~mm-fix-a-vmscan-warning +++ a/mm/vmscan.c @@ -2283,7 +2283,7 @@ unsigned long mem_cgroup_shrink_node_zon .mem_cgroup = mem, .memcg_record = rec, }; - unsigned long start, end; + ktime_t start, end; sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) | (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK); @@ -2292,7 +2292,7 @@ unsigned long mem_cgroup_shrink_node_zon sc.may_writepage, sc.gfp_mask); - start = sched_clock(); + start = ktime_get(); /* * NOTE: Although we can get the priority field, using it * here is not a good idea, since it limits the pages we can scan. @@ -2301,10 +2301,10 @@ unsigned long mem_cgroup_shrink_node_zon * the priority and make it zero. */ shrink_zone(0, zone, &sc); - end = sched_clock(); + end = ktime_get(); if (rec) - rec->elapsed += end - start; + rec->elapsed += ktime_to_ns(ktime_sub(end, start)); *scanned = sc.nr_scanned; trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed); @@ -2319,7 +2319,7 @@ unsigned long try_to_free_mem_cgroup_pag { struct zonelist *zonelist; unsigned long nr_reclaimed; - unsigned long start, end; + ktime_t start, end; int nid; struct scan_control sc = { .may_writepage = !laptop_mode, @@ -2337,7 +2337,7 @@ unsigned long try_to_free_mem_cgroup_pag .gfp_mask = sc.gfp_mask, }; - start = sched_clock(); + start = ktime_get(); /* * Unlike direct reclaim via alloc_pages(), memcg's reclaim doesn't * take care of from where we get pages. So the node where we start the @@ -2352,9 +2352,9 @@ unsigned long try_to_free_mem_cgroup_pag sc.gfp_mask); nr_reclaimed = do_try_to_free_pages(zonelist, &sc, &shrink); - end = sched_clock(); + end = ktime_get(); if (rec) - rec->elapsed += end - start; + rec->elapsed += ktime_to_ns(ktime_sub(end, start)); trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed); _ Patches currently in -mm which might be from shaohua.li@xxxxxxxxx are mm-fix-a-vmscan-warning.patch linux-next.patch vmscan-add-block-plug-for-page-reclaim.patch intel_idle-fix-api-misuse.patch intel_idle-disable-auto_demotion-for-hotplugged-cpus.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html