On 5/15/19 1:55 PM, Konstantin Khlebnikov wrote:
> Socket buffers always were dark-matter that lives by its own rules.
Is the information even exported somewhere e.g. in sysfs or via netlink yet?
> This patch adds line NetBuffers that exposes most common kinds of them.
Did you encounter a situation where the number was significant and this
would help finding out why memory is occupied?
> TCP and UDP are most important species.
> SCTP is added as example of modular protocol.
> UNIX have no memory counter for now, should be easy to add.
>
> Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Right now it's a sum of a few values, which should be fine wrt
/proc/meminfo overhead. But I guess netdev guys should have a say in
this. Also you should update the corresponding Documentation/ file.
Thanks,
Vlastimil
> ---
> fs/proc/meminfo.c | 5 ++++-
> include/linux/mm.h | 6 ++++++
> mm/page_alloc.c | 3 ++-
> net/core/sock.c | 20 ++++++++++++++++++++
> net/sctp/socket.c | 2 +-
> 5 files changed, 33 insertions(+), 3 deletions(-)
>
> diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
> index 7bc14716fc5d..0ee2300a916d 100644
> --- a/fs/proc/meminfo.c
> +++ b/fs/proc/meminfo.c
> @@ -41,6 +41,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
> unsigned long sreclaimable, sunreclaim, misc_reclaimable;
> unsigned long kernel_stack_kb, page_tables, percpu_pages;
> unsigned long anon_pages, file_pages, swap_cached;
> + unsigned long net_buffers;
> long kernel_misc;
> int lru;
>
> @@ -66,12 +67,13 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
> kernel_stack_kb = global_zone_page_state(NR_KERNEL_STACK_KB);
> page_tables = global_zone_page_state(NR_PAGETABLE);
> percpu_pages = pcpu_nr_pages();
> + net_buffers = total_netbuffer_pages();
>
> /* all other kinds of kernel memory allocations */
> kernel_misc = i.totalram - i.freeram - anon_pages - file_pages
> - sreclaimable - sunreclaim - misc_reclaimable
> - (kernel_stack_kb >> (PAGE_SHIFT - 10))
> - - page_tables - percpu_pages;
> + - page_tables - percpu_pages - net_buffers;
> if (kernel_misc < 0)
> kernel_misc = 0;
>
> @@ -137,6 +139,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
> show_val_kb(m, "VmallocUsed: ", 0ul);
> show_val_kb(m, "VmallocChunk: ", 0ul);
> show_val_kb(m, "Percpu: ", percpu_pages);
> + show_val_kb(m, "NetBuffers: ", net_buffers);
> show_val_kb(m, "KernelMisc: ", kernel_misc);
>
> #ifdef CONFIG_MEMORY_FAILURE
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 0e8834ac32b7..d0a58355bfb7 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -2254,6 +2254,12 @@ extern void si_meminfo_node(struct sysinfo *val, int nid);
> extern unsigned long arch_reserved_kernel_pages(void);
> #endif
>
> +#ifdef CONFIG_NET
> +extern unsigned long total_netbuffer_pages(void);
> +#else
> +static inline unsigned long total_netbuffer_pages(void) { return 0; }
> +#endif
> +
> extern __printf(3, 4)
> void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 3b13d3914176..fcdd7c6e72b9 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -5166,7 +5166,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
> " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
> " unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n"
> " slab_reclaimable:%lu slab_unreclaimable:%lu\n"
> - " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
> + " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu net_buffers:%lu\n"
> " free:%lu free_pcp:%lu free_cma:%lu\n",
> global_node_page_state(NR_ACTIVE_ANON),
> global_node_page_state(NR_INACTIVE_ANON),
> @@ -5184,6 +5184,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
> global_node_page_state(NR_SHMEM),
> global_zone_page_state(NR_PAGETABLE),
> global_zone_page_state(NR_BOUNCE),
> + total_netbuffer_pages(),
> global_zone_page_state(NR_FREE_PAGES),
> free_pcp,
> global_zone_page_state(NR_FREE_CMA_PAGES));
> diff --git a/net/core/sock.c b/net/core/sock.c
> index 75b1c950b49f..dfca4e024b74 100644
> --- a/net/core/sock.c
> +++ b/net/core/sock.c
> @@ -142,6 +142,7 @@
> #include <trace/events/sock.h>
>
> #include <net/tcp.h>
> +#include <net/udp.h>
> #include <net/busy_poll.h>
>
> static DEFINE_MUTEX(proto_list_mutex);
> @@ -3573,3 +3574,22 @@ bool sk_busy_loop_end(void *p, unsigned long start_time)
> }
> EXPORT_SYMBOL(sk_busy_loop_end);
> #endif /* CONFIG_NET_RX_BUSY_POLL */
> +
> +#if IS_ENABLED(CONFIG_IP_SCTP)
> +atomic_long_t sctp_memory_allocated;
> +EXPORT_SYMBOL_GPL(sctp_memory_allocated);
> +#endif
> +
> +unsigned long total_netbuffer_pages(void)
> +{
> + unsigned long ret = 0;
> +
> +#if IS_ENABLED(CONFIG_IP_SCTP)
> + ret += atomic_long_read(&sctp_memory_allocated);
> +#endif
> +#ifdef CONFIG_INET
> + ret += atomic_long_read(&tcp_memory_allocated);
> + ret += atomic_long_read(&udp_memory_allocated);
> +#endif
> + return ret;
> +}
> diff --git a/net/sctp/socket.c b/net/sctp/socket.c
> index e4e892cc5644..9d11afdeeae4 100644
> --- a/net/sctp/socket.c
> +++ b/net/sctp/socket.c
> @@ -107,7 +107,7 @@ static int sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
> enum sctp_socket_type type);
>
> static unsigned long sctp_memory_pressure;
> -static atomic_long_t sctp_memory_allocated;
> +extern atomic_long_t sctp_memory_allocated;
> struct percpu_counter sctp_sockets_allocated;
>
> static void sctp_enter_memory_pressure(struct sock *sk)
>
