* [RFC PATCH 2/9] bpf: allow up to 13 arguments for tracepoints
[not found] <20200409193543.18115-1-mathieu.desnoyers@efficios.com>
@ 2020-04-09 19:35 ` Mathieu Desnoyers
2020-04-09 19:35 ` [RFC PATCH 3/9] writeback: tracing: pass global_wb_domain as tracepoint parameter Mathieu Desnoyers
1 sibling, 0 replies; 4+ messages in thread
From: Mathieu Desnoyers @ 2020-04-09 19:35 UTC (permalink / raw)
To: Thomas Gleixner, Will Deacon, akpm, Greg Kroah-Hartman,
K . Prasad, Masami Hiramatsu, rostedt, Alexei Starovoitov
Cc: linux-kernel, Mathieu Desnoyers, Daniel Borkmann, Ingo Molnar,
bpf, netdev
Adding an argument to the writeback balance_dirty_pages event requires
to bump the bpf argument count limit from 12 to 13.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
---
include/linux/kernel.h | 6 +++---
include/linux/trace_events.h | 3 +++
include/trace/bpf_probe.h | 3 ++-
kernel/trace/bpf_trace.c | 8 +++++---
4 files changed, 13 insertions(+), 7 deletions(-)
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 9b7a8d74a9d6..20203f762410 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -975,9 +975,9 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
#define swap(a, b) \
do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
-/* This counts to 12. Any more, it will return 13th argument. */
-#define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n
-#define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
+/* This counts to 13. Any more, it will return 14th argument. */
+#define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _n, X...) _n
+#define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
#define __CONCAT(a, b) a ## b
#define CONCATENATE(a, b) __CONCAT(a, b)
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 5c6943354049..1e3f4782d32f 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -776,6 +776,9 @@ void bpf_trace_run11(struct bpf_prog *prog, u64 arg1, u64 arg2,
void bpf_trace_run12(struct bpf_prog *prog, u64 arg1, u64 arg2,
u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12);
+void bpf_trace_run13(struct bpf_prog *prog, u64 arg1, u64 arg2,
+ u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7,
+ u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12, u64 arg13);
void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
struct trace_event_call *call, u64 count,
struct pt_regs *regs, struct hlist_head *head,
diff --git a/include/trace/bpf_probe.h b/include/trace/bpf_probe.h
index 1ce3be63add1..1ca87b7a8230 100644
--- a/include/trace/bpf_probe.h
+++ b/include/trace/bpf_probe.h
@@ -52,7 +52,8 @@
#define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
#define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
#define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
-/* tracepoints with more than 12 arguments will hit build error */
+#define __CAST13(a,...) __CAST_TO_U64(a), __CAST12(__VA_ARGS__)
+/* tracepoints with more than 13 arguments will hit build error */
#define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)
#undef DECLARE_EVENT_CLASS
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index ca1796747a77..67354218b97f 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1546,6 +1546,7 @@ void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
#define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
#define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
#define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
+#define REPEAT_13(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_12(FN, DL, __VA_ARGS__)
#define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
#define SARG(X) u64 arg##X
@@ -1554,14 +1555,14 @@ void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
#define __DL_COM (,)
#define __DL_SEM (;)
-#define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+#define __SEQ_0_12 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12
#define BPF_TRACE_DEFN_x(x) \
void bpf_trace_run##x(struct bpf_prog *prog, \
- REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
+ REPEAT(x, SARG, __DL_COM, __SEQ_0_12)) \
{ \
u64 args[x]; \
- REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
+ REPEAT(x, COPY, __DL_SEM, __SEQ_0_12); \
__bpf_trace_run(prog, args); \
} \
EXPORT_SYMBOL_GPL(bpf_trace_run##x)
@@ -1577,6 +1578,7 @@ BPF_TRACE_DEFN_x(9);
BPF_TRACE_DEFN_x(10);
BPF_TRACE_DEFN_x(11);
BPF_TRACE_DEFN_x(12);
+BPF_TRACE_DEFN_x(13);
static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
{
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [RFC PATCH 3/9] writeback: tracing: pass global_wb_domain as tracepoint parameter
[not found] <20200409193543.18115-1-mathieu.desnoyers@efficios.com>
2020-04-09 19:35 ` [RFC PATCH 2/9] bpf: allow up to 13 arguments for tracepoints Mathieu Desnoyers
@ 2020-04-09 19:35 ` Mathieu Desnoyers
2020-04-09 22:33 ` Alexei Starovoitov
1 sibling, 1 reply; 4+ messages in thread
From: Mathieu Desnoyers @ 2020-04-09 19:35 UTC (permalink / raw)
To: Thomas Gleixner, Will Deacon, akpm, Greg Kroah-Hartman,
K . Prasad, Masami Hiramatsu, rostedt, Alexei Starovoitov
Cc: linux-kernel, Mathieu Desnoyers, Daniel Borkmann, Ingo Molnar,
bpf, netdev
The symbol global_wb_domain is not GPL-exported to modules. In order
to allow kernel tracers implemented as GPL modules to access the
global writeback domain dirty limit, as used within the
global_dirty_state and balance_dirty_pages trace events, pass
a pointer to the global writeback domain as a new parameter for
those tracepoints.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
---
include/trace/events/writeback.h | 17 ++++++++++-------
mm/page-writeback.c | 9 +++++----
2 files changed, 15 insertions(+), 11 deletions(-)
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index d94def25e4dc..8fd774108c9c 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -531,11 +531,13 @@ TRACE_EVENT(writeback_queue_io,
TRACE_EVENT(global_dirty_state,
- TP_PROTO(unsigned long background_thresh,
+ TP_PROTO(struct wb_domain *domain,
+ unsigned long background_thresh,
unsigned long dirty_thresh
),
- TP_ARGS(background_thresh,
+ TP_ARGS(domain,
+ background_thresh,
dirty_thresh
),
@@ -558,7 +560,7 @@ TRACE_EVENT(global_dirty_state,
__entry->nr_written = global_node_page_state(NR_WRITTEN);
__entry->background_thresh = background_thresh;
__entry->dirty_thresh = dirty_thresh;
- __entry->dirty_limit = global_wb_domain.dirty_limit;
+ __entry->dirty_limit = domain->dirty_limit;
),
TP_printk("dirty=%lu writeback=%lu unstable=%lu "
@@ -625,7 +627,8 @@ TRACE_EVENT(bdi_dirty_ratelimit,
TRACE_EVENT(balance_dirty_pages,
- TP_PROTO(struct bdi_writeback *wb,
+ TP_PROTO(struct wb_domain *domain,
+ struct bdi_writeback *wb,
unsigned long thresh,
unsigned long bg_thresh,
unsigned long dirty,
@@ -638,7 +641,7 @@ TRACE_EVENT(balance_dirty_pages,
long pause,
unsigned long start_time),
- TP_ARGS(wb, thresh, bg_thresh, dirty, bdi_thresh, bdi_dirty,
+ TP_ARGS(domain, wb, thresh, bg_thresh, dirty, bdi_thresh, bdi_dirty,
dirty_ratelimit, task_ratelimit,
dirtied, period, pause, start_time),
@@ -664,8 +667,8 @@ TRACE_EVENT(balance_dirty_pages,
unsigned long freerun = (thresh + bg_thresh) / 2;
strscpy_pad(__entry->bdi, bdi_dev_name(wb->bdi), 32);
- __entry->limit = global_wb_domain.dirty_limit;
- __entry->setpoint = (global_wb_domain.dirty_limit +
+ __entry->limit = domain->dirty_limit;
+ __entry->setpoint = (domain->dirty_limit +
freerun) / 2;
__entry->dirty = dirty;
__entry->bdi_setpoint = __entry->setpoint *
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 7326b54ab728..c76aae305360 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -443,9 +443,8 @@ static void domain_dirty_limits(struct dirty_throttle_control *dtc)
dtc->thresh = thresh;
dtc->bg_thresh = bg_thresh;
- /* we should eventually report the domain in the TP */
if (!gdtc)
- trace_global_dirty_state(bg_thresh, thresh);
+ trace_global_dirty_state(&global_wb_domain, bg_thresh, thresh);
}
/**
@@ -1736,7 +1735,8 @@ static void balance_dirty_pages(struct bdi_writeback *wb,
* do a reset, as it may be a light dirtier.
*/
if (pause < min_pause) {
- trace_balance_dirty_pages(wb,
+ trace_balance_dirty_pages(&global_wb_domain,
+ wb,
sdtc->thresh,
sdtc->bg_thresh,
sdtc->dirty,
@@ -1765,7 +1765,8 @@ static void balance_dirty_pages(struct bdi_writeback *wb,
}
pause:
- trace_balance_dirty_pages(wb,
+ trace_balance_dirty_pages(&global_wb_domain,
+ wb,
sdtc->thresh,
sdtc->bg_thresh,
sdtc->dirty,
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread