percpu: improve percpu_alloc_percpu event trace

Add call_site, bytes_alloc and gfp_flags fields to the output of the
percpu_alloc_percpu ftrace event:

mkdir-4393  [001]   169.334788: percpu_alloc_percpu:
 call_site=mem_cgroup_css_alloc+0xa6 reserved=0 is_atomic=0 size=2408 align=8
  base_addr=0xffffc7117fc00000 off=402176 ptr=0x3dc867a62300 bytes_alloc=14448
   gfp_flags=GFP_KERNEL_ACCOUNT

This is required to track memcg-accounted percpu allocations.

Link: https://lkml.kernel.org/r/a07be858-c8a3-7851-9086-e3262cbcf707@openvz.org
Signed-off-by: Vasily Averin <vvs@openvz.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/trace/events/percpu.h b/include/trace/events/percpu.h
index df112a6..e989cef 100644 (file)
--- a/include/trace/events/percpu.h
+++ b/include/trace/events/percpu.h
@@ -6,15 +6,20 @@
 #define _TRACE_PERCPU_H
 
 #include <linux/tracepoint.h>
+#include <trace/events/mmflags.h>
 
 TRACE_EVENT(percpu_alloc_percpu,
 
-       TP_PROTO(bool reserved, bool is_atomic, size_t size,
-                size_t align, void *base_addr, int off, void __percpu *ptr),
+       TP_PROTO(unsigned long call_site,
+                bool reserved, bool is_atomic, size_t size,
+                size_t align, void *base_addr, int off,
+                void __percpu *ptr, size_t bytes_alloc, gfp_t gfp_flags),
 
-       TP_ARGS(reserved, is_atomic, size, align, base_addr, off, ptr),
+       TP_ARGS(call_site, reserved, is_atomic, size, align, base_addr, off,
+               ptr, bytes_alloc, gfp_flags),
 
        TP_STRUCT__entry(
+               __field(        unsigned long,          call_site       )
                __field(        bool,                   reserved        )
                __field(        bool,                   is_atomic       )
                __field(        size_t,                 size            )
@@ -22,9 +27,11 @@ TRACE_EVENT(percpu_alloc_percpu,
                __field(        void *,                 base_addr       )
                __field(        int,                    off             )
                __field(        void __percpu *,        ptr             )
+               __field(        size_t,                 bytes_alloc     )
+               __field(        gfp_t,                  gfp_flags       )
        ),
-
        TP_fast_assign(
+               __entry->call_site      = call_site;
                __entry->reserved       = reserved;
                __entry->is_atomic      = is_atomic;
                __entry->size           = size;
@@ -32,12 +39,16 @@ TRACE_EVENT(percpu_alloc_percpu,
                __entry->base_addr      = base_addr;
                __entry->off            = off;
                __entry->ptr            = ptr;
+               __entry->bytes_alloc    = bytes_alloc;
+               __entry->gfp_flags      = gfp_flags;
        ),
 
-       TP_printk("reserved=%d is_atomic=%d size=%zu align=%zu base_addr=%p off=%d ptr=%p",
+       TP_printk("call_site=%pS reserved=%d is_atomic=%d size=%zu align=%zu base_addr=%p off=%d ptr=%p bytes_alloc=%zu gfp_flags=%s",
+                 (void *)__entry->call_site,
                  __entry->reserved, __entry->is_atomic,
                  __entry->size, __entry->align,
-                 __entry->base_addr, __entry->off, __entry->ptr)
+                 __entry->base_addr, __entry->off, __entry->ptr,
+                 __entry->bytes_alloc, show_gfp_flags(__entry->gfp_flags))
 );
 
 TRACE_EVENT(percpu_free_percpu,

diff --git a/mm/percpu-internal.h b/mm/percpu-internal.h
index 411d159..70b1ea2 100644 (file)
--- a/mm/percpu-internal.h
+++ b/mm/percpu-internal.h
@@ -113,7 +113,6 @@ static inline int pcpu_chunk_map_bits(struct pcpu_chunk *chunk)
        return pcpu_nr_pages_to_map_bits(chunk->nr_pages);
 }
 
-#ifdef CONFIG_MEMCG_KMEM
 /**
  * pcpu_obj_full_size - helper to calculate size of each accounted object
  * @size: size of area to allocate in bytes
@@ -123,13 +122,14 @@ static inline int pcpu_chunk_map_bits(struct pcpu_chunk *chunk)
  */
 static inline size_t pcpu_obj_full_size(size_t size)
 {
-       size_t extra_size;
+       size_t extra_size = 0;
 
-       extra_size = size / PCPU_MIN_ALLOC_SIZE * sizeof(struct obj_cgroup *);
+#ifdef CONFIG_MEMCG_KMEM
+       extra_size += size / PCPU_MIN_ALLOC_SIZE * sizeof(struct obj_cgroup *);
+#endif
 
        return size * num_possible_cpus() + extra_size;
 }
-#endif /* CONFIG_MEMCG_KMEM */
 
 #ifdef CONFIG_PERCPU_STATS
 

diff --git a/mm/percpu.c b/mm/percpu.c
index ea28db2..3633eee 100644 (file)
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1884,8 +1884,9 @@ area_found:
        ptr = __addr_to_pcpu_ptr(chunk->base_addr + off);
        kmemleak_alloc_percpu(ptr, size, gfp);
 
-       trace_percpu_alloc_percpu(reserved, is_atomic, size, align,
-                       chunk->base_addr, off, ptr);
+       trace_percpu_alloc_percpu(_RET_IP_, reserved, is_atomic, size, align,
+                                 chunk->base_addr, off, ptr,
+                                 pcpu_obj_full_size(size), gfp);
 
        pcpu_memcg_post_alloc_hook(objcg, chunk, off, size);