----- Original Message -----
> Since Linux v3.4 (specifically, commit 438ced1720b584000 "ring-buffer:
> Add per_cpu ring buffer control files"), the trace buffer size is now
> per-cpu. The patch below updates the trace extension to handle this.
>
> Rabin
The patch looks good to me -- deferring to the trace.c maintainer
Lai Jiangshan (cc'd directory) for his ACK.
Thanks,
Dave
>
> diff --git a/extensions/trace.c b/extensions/trace.c
> index 831cc77..224c662 100644
> --- a/extensions/trace.c
> +++ b/extensions/trace.c
> @@ -24,6 +24,7 @@ static int nr_cpu_ids;
> * lockless ring_buffer and old non-lockless ring_buffer are both
> supported.
> */
> static int lockless_ring_buffer;
> +static int per_cpu_buffer_sizes;
>
> #define koffset(struct, member) struct##_##member##_offset
>
> @@ -37,6 +38,7 @@ static int koffset(ring_buffer, buffers);
>
> static int koffset(ring_buffer_per_cpu, cpu);
> static int koffset(ring_buffer_per_cpu, pages);
> +static int koffset(ring_buffer_per_cpu, nr_pages);
> static int koffset(ring_buffer_per_cpu, head_page);
> static int koffset(ring_buffer_per_cpu, tail_page);
> static int koffset(ring_buffer_per_cpu, commit_page);
> @@ -71,6 +73,7 @@ struct ring_buffer_per_cpu {
> ulong real_head_page;
>
> int head_page_index;
> + unsigned int nr_pages;
> ulong *pages;
>
> ulong *linear_pages;
> @@ -144,7 +147,14 @@ static int init_offsets(void)
> init_offset(trace_array, buffer);
> init_offset(tracer, name);
>
> - init_offset(ring_buffer, pages);
> + if (MEMBER_EXISTS("ring_buffer_per_cpu", "nr_pages")) {
> + per_cpu_buffer_sizes = 1;
> + if (verbose)
> + fprintf(fp, "per cpu buffer sizes\n");
> + }
> +
> + if (!per_cpu_buffer_sizes)
> + init_offset(ring_buffer, pages);
> init_offset(ring_buffer, flags);
> init_offset(ring_buffer, cpus);
> init_offset(ring_buffer, buffers);
> @@ -155,6 +165,8 @@ static int init_offsets(void)
> fprintf(fp, "lockless\n");
> }
>
> + if (per_cpu_buffer_sizes)
> + init_offset(ring_buffer_per_cpu, nr_pages);
> init_offset(ring_buffer_per_cpu, cpu);
> init_offset(ring_buffer_per_cpu, pages);
> init_offset(ring_buffer_per_cpu, head_page);
> @@ -362,6 +374,10 @@ static int ftrace_init_buffers(struct
> ring_buffer_per_cpu *buffers,
> buffer_read_value(reader_page);
> buffer_read_value(overrun);
> buffer_read_value(entries);
> + if (per_cpu_buffer_sizes) {
> + buffer_read_value(nr_pages);
> + pages = buffers[i].nr_pages;
> + }
> #undef buffer_read_value
>
> if (ftrace_init_pages(buffers + i, pages) < 0)
> --
> 1.7.9.5
>
> --
> Crash-utility mailing list
> [email protected]
> https://www.redhat.com/mailman/listinfo/crash-utility
>
--
Crash-utility mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/crash-utility
