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compat: work around broken _SC_NPROCESSORS_CONF on MUSL libc
[lttng-ust.git]
/
libringbuffer
/
frontend_api.h
diff --git
a/libringbuffer/frontend_api.h
b/libringbuffer/frontend_api.h
index 56dbef2aa4326c8a4067ecc96ada66b887358afd..bc1fd1220ba97c21da824ac326d81d4edf789a8a 100644
(file)
--- a/
libringbuffer/frontend_api.h
+++ b/
libringbuffer/frontend_api.h
@@
-37,10
+37,10
@@
/**
* lib_ring_buffer_get_cpu - Precedes ring buffer reserve/commit.
*
/**
* lib_ring_buffer_get_cpu - Precedes ring buffer reserve/commit.
*
- *
Grabs RCU read-side lock and keeps a ring buffer nesting count as
- *
supplementary safety net to ensure tracer client code will never
- *
trigger an endless recursion. Returns the processor ID on success,
- *
-EPERM on failure (nesting count
too high).
+ *
Keeps a ring buffer nesting count as supplementary safety net to
+ *
ensure tracer client code will never trigger an endless recursion.
+ *
Returns the processor ID on success, -EPERM on failure (nesting count
+ * too high).
*
* asm volatile and "memory" clobber prevent the compiler from moving
* instructions out of the ring buffer nesting count. This is required to ensure
*
* asm volatile and "memory" clobber prevent the compiler from moving
* instructions out of the ring buffer nesting count. This is required to ensure
@@
-53,7
+53,6
@@
int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *confi
{
int cpu, nesting;
{
int cpu, nesting;
- rcu_read_lock();
cpu = lttng_ust_get_cpu();
nesting = ++URCU_TLS(lib_ring_buffer_nesting);
cmm_barrier();
cpu = lttng_ust_get_cpu();
nesting = ++URCU_TLS(lib_ring_buffer_nesting);
cmm_barrier();
@@
-61,7
+60,6
@@
int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *confi
if (caa_unlikely(nesting > 4)) {
WARN_ON_ONCE(1);
URCU_TLS(lib_ring_buffer_nesting)--;
if (caa_unlikely(nesting > 4)) {
WARN_ON_ONCE(1);
URCU_TLS(lib_ring_buffer_nesting)--;
- rcu_read_unlock();
return -EPERM;
} else
return cpu;
return -EPERM;
} else
return cpu;
@@
-75,7
+73,6
@@
void lib_ring_buffer_put_cpu(const struct lttng_ust_lib_ring_buffer_config *conf
{
cmm_barrier();
URCU_TLS(lib_ring_buffer_nesting)--; /* TLS */
{
cmm_barrier();
URCU_TLS(lib_ring_buffer_nesting)--; /* TLS */
- rcu_read_unlock();
}
/*
}
/*
@@
-87,6
+84,7
@@
void lib_ring_buffer_put_cpu(const struct lttng_ust_lib_ring_buffer_config *conf
static inline
int lib_ring_buffer_try_reserve(const struct lttng_ust_lib_ring_buffer_config *config,
struct lttng_ust_lib_ring_buffer_ctx *ctx,
static inline
int lib_ring_buffer_try_reserve(const struct lttng_ust_lib_ring_buffer_config *config,
struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ void *client_ctx,
unsigned long *o_begin, unsigned long *o_end,
unsigned long *o_old, size_t *before_hdr_pad)
{
unsigned long *o_begin, unsigned long *o_end,
unsigned long *o_old, size_t *before_hdr_pad)
{
@@
-113,7
+111,7
@@
int lib_ring_buffer_try_reserve(const struct lttng_ust_lib_ring_buffer_config *c
return 1;
ctx->slot_size = record_header_size(config, chan, *o_begin,
return 1;
ctx->slot_size = record_header_size(config, chan, *o_begin,
- before_hdr_pad, ctx);
+ before_hdr_pad, ctx
, client_ctx
);
ctx->slot_size +=
lib_ring_buffer_align(*o_begin + ctx->slot_size,
ctx->largest_align) + ctx->data_size;
ctx->slot_size +=
lib_ring_buffer_align(*o_begin + ctx->slot_size,
ctx->largest_align) + ctx->data_size;
@@
-155,7
+153,8
@@
int lib_ring_buffer_try_reserve(const struct lttng_ust_lib_ring_buffer_config *c
static inline
int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *config,
static inline
int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *config,
- struct lttng_ust_lib_ring_buffer_ctx *ctx)
+ struct lttng_ust_lib_ring_buffer_ctx *ctx,
+ void *client_ctx)
{
struct channel *chan = ctx->chan;
struct lttng_ust_shm_handle *handle = ctx->handle;
{
struct channel *chan = ctx->chan;
struct lttng_ust_shm_handle *handle = ctx->handle;
@@
-163,21
+162,23
@@
int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *confi
unsigned long o_begin, o_end, o_old;
size_t before_hdr_pad = 0;
unsigned long o_begin, o_end, o_old;
size_t before_hdr_pad = 0;
- if (
uatomic_read(&chan->record_disabled
))
+ if (
caa_unlikely(uatomic_read(&chan->record_disabled)
))
return -EAGAIN;
if (config->alloc == RING_BUFFER_ALLOC_PER_CPU)
buf = shmp(handle, chan->backend.buf[ctx->cpu].shmp);
else
buf = shmp(handle, chan->backend.buf[0].shmp);
return -EAGAIN;
if (config->alloc == RING_BUFFER_ALLOC_PER_CPU)
buf = shmp(handle, chan->backend.buf[ctx->cpu].shmp);
else
buf = shmp(handle, chan->backend.buf[0].shmp);
- if (uatomic_read(&buf->record_disabled))
+ if (caa_unlikely(!buf))
+ return -EIO;
+ if (caa_unlikely(uatomic_read(&buf->record_disabled)))
return -EAGAIN;
ctx->buf = buf;
/*
* Perform retryable operations.
*/
return -EAGAIN;
ctx->buf = buf;
/*
* Perform retryable operations.
*/
- if (caa_unlikely(lib_ring_buffer_try_reserve(config, ctx, &o_begin,
+ if (caa_unlikely(lib_ring_buffer_try_reserve(config, ctx,
client_ctx,
&o_begin,
&o_end, &o_old, &before_hdr_pad)))
goto slow_path;
&o_end, &o_old, &before_hdr_pad)))
goto slow_path;
@@
-208,7
+209,7
@@
int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *confi
ctx->buf_offset = o_begin + before_hdr_pad;
return 0;
slow_path:
ctx->buf_offset = o_begin + before_hdr_pad;
return 0;
slow_path:
- return lib_ring_buffer_reserve_slow(ctx);
+ return lib_ring_buffer_reserve_slow(ctx
, client_ctx
);
}
/**
}
/**
@@
-253,11
+254,16
@@
void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
unsigned long offset_end = ctx->buf_offset;
unsigned long endidx = subbuf_index(offset_end - 1, chan);
unsigned long commit_count;
unsigned long offset_end = ctx->buf_offset;
unsigned long endidx = subbuf_index(offset_end - 1, chan);
unsigned long commit_count;
+ struct commit_counters_hot *cc_hot = shmp_index(handle,
+ buf->commit_hot, endidx);
+
+ if (caa_unlikely(!cc_hot))
+ return;
/*
* Must count record before incrementing the commit count.
*/
/*
* Must count record before incrementing the commit count.
*/
- subbuffer_count_record(config, &buf->backend, endidx, handle);
+ subbuffer_count_record(config,
ctx,
&buf->backend, endidx, handle);
/*
* Order all writes to buffer before the commit count update that will
/*
* Order all writes to buffer before the commit count update that will
@@
-265,7
+271,7
@@
void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
*/
cmm_smp_wmb();
*/
cmm_smp_wmb();
- v_add(config, ctx->slot_size, &
shmp_index(handle, buf->commit_hot, endidx)
->cc);
+ v_add(config, ctx->slot_size, &
cc_hot
->cc);
/*
* commit count read can race with concurrent OOO commit count updates.
/*
* commit count read can race with concurrent OOO commit count updates.
@@
-285,7
+291,7
@@
void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
* count reaches back the reserve offset for a specific sub-buffer,
* which is completely independent of the order.
*/
* count reaches back the reserve offset for a specific sub-buffer,
* which is completely independent of the order.
*/
- commit_count = v_read(config, &
shmp_index(handle, buf->commit_hot, endidx)
->cc);
+ commit_count = v_read(config, &
cc_hot
->cc);
lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1,
commit_count, endidx, handle, ctx->tsc);
lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1,
commit_count, endidx, handle, ctx->tsc);
@@
-293,8
+299,8
@@
void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *confi
* Update used size at each commit. It's needed only for extracting
* ring_buffer buffers from vmcore, after crash.
*/
* Update used size at each commit. It's needed only for extracting
* ring_buffer buffers from vmcore, after crash.
*/
- lib_ring_buffer_write_commit_counter(config, buf, chan,
endidx,
- offset_end, commit_count, handle);
+ lib_ring_buffer_write_commit_counter(config, buf, chan,
+ offset_end, commit_count, handle
, cc_hot
);
}
/**
}
/**
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