From f51bdd2e97098a5cbb3cba7c3a56fa0e9ac3c444 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Thu, 25 Aug 2011 15:59:10 -0700 Subject: 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: [] debug_smp_processor_id+0xc2/0xdc [] native_sched_clock+0x37/0x6e [] try_to_free_mem_cgroup_pages+0x7d/0x270 [] mem_cgroup_force_empty+0x24b/0x27a [] ? sys_close+0x38/0x138 [] ? sys_close+0x38/0x138 [] mem_cgroup_force_empty_write+0x17/0x19 [] cgroup_file_write+0xa8/0xba [] vfs_write+0xb3/0x138 [] sys_write+0x4a/0x71 [] ? sys_close+0xf0/0x138 [] 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 Acked-by: KAMEZAWA Hiroyuki Tested-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'mm') diff --git a/mm/vmscan.c b/mm/vmscan.c index 7ef69124fa3e..22631e0994b3 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2283,7 +2283,7 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem, .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_zone(struct mem_cgroup *mem, 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_zone(struct mem_cgroup *mem, * 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_pages(struct mem_cgroup *mem_cont, { 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_pages(struct mem_cgroup *mem_cont, .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_pages(struct mem_cgroup *mem_cont, 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); -- cgit v1.2.3-59-g8ed1b