libdispatch-913.30.4.tar.gz

[apple/libdispatch.git] / src / firehose / firehose_buffer.c

diff --git a/src/firehose/firehose_buffer.c b/src/firehose/firehose_buffer.c
index a9b5af27669fa7229601b6d7b0adb9c0f820a633..3bb790c7cdde85a36dc6be76eec001c3d5b60a3d 100644 (file)
--- a/src/firehose/firehose_buffer.c
+++ b/src/firehose/firehose_buffer.c
@@ -37,6 +37,10 @@
 #define likely(x)   __builtin_expect(!!(x), 1)
 #define unlikely(x) __builtin_expect(!!(x), 0)
 
 #define likely(x)   __builtin_expect(!!(x), 1)
 #define unlikely(x) __builtin_expect(!!(x), 0)
 

+#ifndef OS_FALLTHROUGH
+#define OS_FALLTHROUGH
+#endif
+

 #define DISPATCH_INTERNAL_CRASH(ac, msg) ({ panic(msg); __builtin_trap(); })
 
 #if defined(__x86_64__) || defined(__i386__)
 #define DISPATCH_INTERNAL_CRASH(ac, msg) ({ panic(msg); __builtin_trap(); })
 
 #if defined(__x86_64__) || defined(__i386__)


@@ -49,10 +53,13 @@
 #define dispatch_hardware_pause() __asm__("")
 #endif
 
 #define dispatch_hardware_pause() __asm__("")
 #endif
 

-#define _dispatch_wait_until(c) do { \
-               while (!fastpath(c)) { \
+#define _dispatch_wait_until(c) ({ \
+               typeof(c) _c; \
+               for (;;) { \
+                       if (likely(_c = (c))) break; \

                        dispatch_hardware_pause(); \
                        dispatch_hardware_pause(); \

-               } } while (0)
+               } \
+               _c; })

 #define dispatch_compiler_barrier()  __asm__ __volatile__("" ::: "memory")
 
 typedef uint32_t dispatch_lock;
 #define dispatch_compiler_barrier()  __asm__ __volatile__("" ::: "memory")
 
 typedef uint32_t dispatch_lock;


@@ -62,6 +69,8 @@ typedef struct dispatch_gate_s {
 #define DLOCK_LOCK_DATA_CONTENTION 0
 static void _dispatch_gate_wait(dispatch_gate_t l, uint32_t flags);
 
 #define DLOCK_LOCK_DATA_CONTENTION 0
 static void _dispatch_gate_wait(dispatch_gate_t l, uint32_t flags);
 

+#define fcp_quarntined fcp_quarantined
+

 #include <kern/debug.h>
 #include <machine/cpu_number.h>
 #include <kern/thread.h>
 #include <kern/debug.h>
 #include <machine/cpu_number.h>
 #include <kern/thread.h>


@@ -443,23 +452,58 @@ firehose_client_send_push_async(firehose_buffer_t fb, qos_class_t qos,
                }
        }
 }
                }
        }
 }

+
+OS_NOINLINE
+static void
+firehose_client_start_quarantine(firehose_buffer_t fb)
+{
+       if (_voucher_libtrace_hooks->vah_version < 5) return;
+       if (!_voucher_libtrace_hooks->vah_quarantine_starts) return;
+
+       _voucher_libtrace_hooks->vah_quarantine_starts();
+
+       fb->fb_header.fbh_quarantined = true;
+       firehose_buffer_stream_flush(fb, firehose_stream_special);
+       firehose_buffer_stream_flush(fb, firehose_stream_persist);
+       firehose_buffer_stream_flush(fb, firehose_stream_memory);
+}

 #endif // !KERNEL
 
 static void
 firehose_client_merge_updates(firehose_buffer_t fb, bool async_notif,
 #endif // !KERNEL
 
 static void
 firehose_client_merge_updates(firehose_buffer_t fb, bool async_notif,

-               firehose_push_reply_t reply, firehose_bank_state_u *state_out)
+               firehose_push_reply_t reply, bool quarantined,
+               firehose_bank_state_u *state_out)

 {
 {

+       firehose_buffer_header_t fbh = &fb->fb_header;

        firehose_bank_state_u state;
        firehose_ring_tail_u otail, ntail;
        uint64_t old_flushed_pos, bank_updates;
        uint16_t io_delta = 0;
        uint16_t mem_delta = 0;
 
        firehose_bank_state_u state;
        firehose_ring_tail_u otail, ntail;
        uint64_t old_flushed_pos, bank_updates;
        uint16_t io_delta = 0;
        uint16_t mem_delta = 0;
 

-       if (firehose_atomic_maxv2o(&fb->fb_header, fbh_bank.fbb_mem_flushed,
+       if (quarantined) {
+#ifndef KERNEL
+               // this isn't a dispatch_once so that the upcall to libtrace
+               // can actually log itself without blocking on the gate.
+               if (async_notif) {
+                       if (os_atomic_xchg(&fbh->fbh_quarantined_state,
+                                       FBH_QUARANTINE_STARTED, relaxed) !=
+                                       FBH_QUARANTINE_STARTED) {
+                               firehose_client_start_quarantine(fb);
+                       }
+               } else if (os_atomic_load(&fbh->fbh_quarantined_state, relaxed) ==
+                               FBH_QUARANTINE_NONE) {
+                       os_atomic_cmpxchg(&fbh->fbh_quarantined_state, FBH_QUARANTINE_NONE,
+                                       FBH_QUARANTINE_PENDING, relaxed);
+               }
+#endif
+       }
+
+       if (firehose_atomic_maxv2o(fbh, fbh_bank.fbb_mem_flushed,

                        reply.fpr_mem_flushed_pos, &old_flushed_pos, relaxed)) {
                mem_delta = (uint16_t)(reply.fpr_mem_flushed_pos - old_flushed_pos);
        }
                        reply.fpr_mem_flushed_pos, &old_flushed_pos, relaxed)) {
                mem_delta = (uint16_t)(reply.fpr_mem_flushed_pos - old_flushed_pos);
        }

-       if (firehose_atomic_maxv2o(&fb->fb_header, fbh_bank.fbb_io_flushed,
+       if (firehose_atomic_maxv2o(fbh, fbh_bank.fbb_io_flushed,

                        reply.fpr_io_flushed_pos, &old_flushed_pos, relaxed)) {
                io_delta = (uint16_t)(reply.fpr_io_flushed_pos - old_flushed_pos);
        }
                        reply.fpr_io_flushed_pos, &old_flushed_pos, relaxed)) {
                io_delta = (uint16_t)(reply.fpr_io_flushed_pos - old_flushed_pos);
        }


@@ -471,14 +515,14 @@ firehose_client_merge_updates(firehose_buffer_t fb, bool async_notif,
 
        if (!mem_delta && !io_delta) {
                if (state_out) {
 
        if (!mem_delta && !io_delta) {
                if (state_out) {

-                       state_out->fbs_atomic_state = os_atomic_load2o(&fb->fb_header,
+                       state_out->fbs_atomic_state = os_atomic_load2o(fbh,

                                        fbh_bank.fbb_state.fbs_atomic_state, relaxed);
                }
                return;
        }
 
        __firehose_critical_region_enter();
                                        fbh_bank.fbb_state.fbs_atomic_state, relaxed);
                }
                return;
        }
 
        __firehose_critical_region_enter();

-       os_atomic_rmw_loop2o(&fb->fb_header, fbh_ring_tail.frp_atomic_tail,
+       os_atomic_rmw_loop2o(fbh, fbh_ring_tail.frp_atomic_tail,

                        otail.frp_atomic_tail, ntail.frp_atomic_tail, relaxed, {
                ntail = otail;
                // overflow handles the generation wraps
                        otail.frp_atomic_tail, ntail.frp_atomic_tail, relaxed, {
                ntail = otail;
                // overflow handles the generation wraps


@@ -488,7 +532,7 @@ firehose_client_merge_updates(firehose_buffer_t fb, bool async_notif,
 
        bank_updates = ((uint64_t)mem_delta << FIREHOSE_BANK_SHIFT(0)) |
                        ((uint64_t)io_delta << FIREHOSE_BANK_SHIFT(1));
 
        bank_updates = ((uint64_t)mem_delta << FIREHOSE_BANK_SHIFT(0)) |
                        ((uint64_t)io_delta << FIREHOSE_BANK_SHIFT(1));

-       state.fbs_atomic_state = os_atomic_sub2o(&fb->fb_header,
+       state.fbs_atomic_state = os_atomic_sub2o(fbh,

                        fbh_bank.fbb_state.fbs_atomic_state, bank_updates, release);
        __firehose_critical_region_leave();
 
                        fbh_bank.fbb_state.fbs_atomic_state, bank_updates, release);
        __firehose_critical_region_leave();
 


@@ -496,29 +540,32 @@ firehose_client_merge_updates(firehose_buffer_t fb, bool async_notif,
 
        if (async_notif) {
                if (io_delta) {
 
        if (async_notif) {
                if (io_delta) {

-                       os_atomic_inc2o(&fb->fb_header, fbh_bank.fbb_io_notifs, relaxed);
+                       os_atomic_inc2o(fbh, fbh_bank.fbb_io_notifs, relaxed);

                }
                if (mem_delta) {
                }
                if (mem_delta) {

-                       os_atomic_inc2o(&fb->fb_header, fbh_bank.fbb_mem_notifs, relaxed);
+                       os_atomic_inc2o(fbh, fbh_bank.fbb_mem_notifs, relaxed);

                }
        }
 }
 
 #ifndef KERNEL
                }
        }
 }
 
 #ifndef KERNEL

+OS_NOT_TAIL_CALLED OS_NOINLINE

 static void
 static void

-firehose_client_send_push(firehose_buffer_t fb, bool for_io,
+firehose_client_send_push_and_wait(firehose_buffer_t fb, bool for_io,

                firehose_bank_state_u *state_out)
 {
        mach_port_t sendp = fb->fb_header.fbh_sendp;
        firehose_push_reply_t push_reply = { };
        qos_class_t qos = qos_class_self();
                firehose_bank_state_u *state_out)
 {
        mach_port_t sendp = fb->fb_header.fbh_sendp;
        firehose_push_reply_t push_reply = { };
        qos_class_t qos = qos_class_self();

+       boolean_t quarantined = false;

        kern_return_t kr;
 
        if (slowpath(sendp == MACH_PORT_DEAD)) {
                return;
        }
        if (fastpath(sendp)) {
        kern_return_t kr;
 
        if (slowpath(sendp == MACH_PORT_DEAD)) {
                return;
        }
        if (fastpath(sendp)) {

-               kr = firehose_send_push(sendp, qos, for_io, &push_reply);
+               kr = firehose_send_push_and_wait(sendp, qos, for_io,
+                               &push_reply, &quarantined);

                if (likely(kr == KERN_SUCCESS)) {
                        goto success;
                }
                if (likely(kr == KERN_SUCCESS)) {
                        goto success;
                }


@@ -530,7 +577,8 @@ firehose_client_send_push(firehose_buffer_t fb, bool for_io,
 
        sendp = firehose_client_reconnect(fb, sendp);
        if (fastpath(MACH_PORT_VALID(sendp))) {
 
        sendp = firehose_client_reconnect(fb, sendp);
        if (fastpath(MACH_PORT_VALID(sendp))) {

-               kr = firehose_send_push(sendp, qos, for_io, &push_reply);
+               kr = firehose_send_push_and_wait(sendp, qos, for_io,
+                               &push_reply, &quarantined);

                if (likely(kr == KERN_SUCCESS)) {
                        goto success;
                }
                if (likely(kr == KERN_SUCCESS)) {
                        goto success;
                }


@@ -566,12 +614,22 @@ success:
        // There only is a point for multithreaded clients if:
        // - enough samples (total_flushes above some limits)
        // - the ratio is really bad (a push per cycle is definitely a problem)
        // There only is a point for multithreaded clients if:
        // - enough samples (total_flushes above some limits)
        // - the ratio is really bad (a push per cycle is definitely a problem)

-       return firehose_client_merge_updates(fb, false, push_reply, state_out);
+       return firehose_client_merge_updates(fb, false, push_reply, quarantined,
+                       state_out);
+}
+
+OS_NOT_TAIL_CALLED OS_NOINLINE
+static void
+__FIREHOSE_CLIENT_THROTTLED_DUE_TO_HEAVY_LOGGING__(firehose_buffer_t fb,
+               bool for_io, firehose_bank_state_u *state_out)
+{
+       firehose_client_send_push_and_wait(fb, for_io, state_out);

 }
 
 kern_return_t
 firehose_client_push_reply(mach_port_t req_port OS_UNUSED,
 }
 
 kern_return_t
 firehose_client_push_reply(mach_port_t req_port OS_UNUSED,

-       kern_return_t rtc, firehose_push_reply_t push_reply OS_UNUSED)
+       kern_return_t rtc, firehose_push_reply_t push_reply OS_UNUSED,
+       boolean_t quarantined OS_UNUSED)

 {
        DISPATCH_INTERNAL_CRASH(rtc, "firehose_push_reply should never be sent "
                        "to the buffer receive port");
 {
        DISPATCH_INTERNAL_CRASH(rtc, "firehose_push_reply should never be sent "
                        "to the buffer receive port");


@@ -579,12 +637,12 @@ firehose_client_push_reply(mach_port_t req_port OS_UNUSED,
 
 kern_return_t
 firehose_client_push_notify_async(mach_port_t server_port OS_UNUSED,
 
 kern_return_t
 firehose_client_push_notify_async(mach_port_t server_port OS_UNUSED,

-       firehose_push_reply_t push_reply)
+       firehose_push_reply_t push_reply, boolean_t quarantined)

 {
        // see _dispatch_source_merge_mach_msg_direct
        dispatch_queue_t dq = _dispatch_queue_get_current();
        firehose_buffer_t fb = dispatch_get_context(dq);
 {
        // see _dispatch_source_merge_mach_msg_direct
        dispatch_queue_t dq = _dispatch_queue_get_current();
        firehose_buffer_t fb = dispatch_get_context(dq);

-       firehose_client_merge_updates(fb, true, push_reply, NULL);
+       firehose_client_merge_updates(fb, true, push_reply, quarantined, NULL);

        return KERN_SUCCESS;
 }
 
        return KERN_SUCCESS;
 }
 


@@ -646,6 +704,7 @@ firehose_buffer_chunk_init(firehose_chunk_t fc,
                .fcp_qos = firehose_buffer_qos_bits_propagate(),
                .fcp_stream = ask->stream,
                .fcp_flag_io = ask->for_io,
                .fcp_qos = firehose_buffer_qos_bits_propagate(),
                .fcp_stream = ask->stream,
                .fcp_flag_io = ask->for_io,

+               .fcp_quarantined = ask->quarantined,

        };
 
        if (privptr) {
        };
 
        if (privptr) {


@@ -661,7 +720,8 @@ firehose_buffer_stream_chunk_install(firehose_buffer_t fb,
 {
        firehose_stream_state_u state, new_state;
        firehose_tracepoint_t ft;
 {
        firehose_stream_state_u state, new_state;
        firehose_tracepoint_t ft;

-       firehose_buffer_stream_t fbs = &fb->fb_header.fbh_stream[ask->stream];
+       firehose_buffer_header_t fbh = &fb->fb_header;
+       firehose_buffer_stream_t fbs = &fbh->fbh_stream[ask->stream];

        uint64_t stamp_and_len;
 
        if (fastpath(ref)) {
        uint64_t stamp_and_len;
 
        if (fastpath(ref)) {


@@ -678,7 +738,7 @@ firehose_buffer_stream_chunk_install(firehose_buffer_t fb,
                ft->ft_thread = _pthread_threadid_self_np_direct();
 #endif
                if (ask->stream == firehose_stream_metadata) {
                ft->ft_thread = _pthread_threadid_self_np_direct();
 #endif
                if (ask->stream == firehose_stream_metadata) {

-                       os_atomic_or2o(fb, fb_header.fbh_bank.fbb_metadata_bitmap,
+                       os_atomic_or2o(fbh, fbh_bank.fbb_metadata_bitmap,

                                        1ULL << ref, relaxed);
                }
                // release barrier to make the chunk init visible
                                        1ULL << ref, relaxed);
                }
                // release barrier to make the chunk init visible


@@ -709,8 +769,11 @@ firehose_buffer_stream_chunk_install(firehose_buffer_t fb,
                ft = NULL;
        }
 
                ft = NULL;
        }
 

+       // pairs with the one in firehose_buffer_tracepoint_reserve()
+       __firehose_critical_region_leave();
+

 #ifndef KERNEL
 #ifndef KERNEL

-       if (unlikely(state.fss_gate.dgl_lock != _dispatch_tid_self())) {
+       if (unlikely(_dispatch_lock_is_locked_by_self(state.fss_gate.dgl_lock))) {

                _dispatch_gate_broadcast_slow(&fbs->fbs_state.fss_gate,
                                state.fss_gate.dgl_lock);
        }
                _dispatch_gate_broadcast_slow(&fbs->fbs_state.fss_gate,
                                state.fss_gate.dgl_lock);
        }


@@ -718,10 +781,16 @@ firehose_buffer_stream_chunk_install(firehose_buffer_t fb,
        if (unlikely(state.fss_current == FIREHOSE_STREAM_STATE_PRISTINE)) {
                firehose_buffer_update_limits(fb);
        }
        if (unlikely(state.fss_current == FIREHOSE_STREAM_STATE_PRISTINE)) {
                firehose_buffer_update_limits(fb);
        }

+
+       if (unlikely(os_atomic_load2o(fbh, fbh_quarantined_state, relaxed) ==
+                       FBH_QUARANTINE_PENDING)) {
+               if (os_atomic_cmpxchg2o(fbh, fbh_quarantined_state,
+                               FBH_QUARANTINE_PENDING, FBH_QUARANTINE_STARTED, relaxed)) {
+                       firehose_client_start_quarantine(fb);
+               }
+       }

 #endif // KERNEL
 
 #endif // KERNEL
 

-       // pairs with the one in firehose_buffer_tracepoint_reserve()
-       __firehose_critical_region_leave();

        return ft;
 }
 
        return ft;
 }
 


@@ -807,7 +876,7 @@ firehose_buffer_ring_enqueue(firehose_buffer_t fb, uint16_t ref)
        gen = head & FIREHOSE_RING_POS_GEN_MASK;
        idx = head & FIREHOSE_RING_POS_IDX_MASK;
 
        gen = head & FIREHOSE_RING_POS_GEN_MASK;
        idx = head & FIREHOSE_RING_POS_IDX_MASK;
 

-       while (unlikely(!os_atomic_cmpxchgvw(&fbh_ring[idx], gen, gen | ref, &dummy,
+       while (unlikely(!os_atomic_cmpxchgv(&fbh_ring[idx], gen, gen | ref, &dummy,

                        relaxed))) {
                // can only ever happen if a recycler is slow, this requires having
                // enough cores (>5 for I/O e.g.)
                        relaxed))) {
                // can only ever happen if a recycler is slow, this requires having
                // enough cores (>5 for I/O e.g.)


@@ -847,7 +916,7 @@ firehose_buffer_ring_enqueue(firehose_buffer_t fb, uint16_t ref)
                // a thread being preempted here for GEN_MASK worth of ring rotations,
                // it could lead to the cmpxchg succeed, and have a bogus enqueue
                // (confused enqueuer)
                // a thread being preempted here for GEN_MASK worth of ring rotations,
                // it could lead to the cmpxchg succeed, and have a bogus enqueue
                // (confused enqueuer)

-               if (fastpath(os_atomic_cmpxchgvw(&fbh_ring[idx], gen, gen | ref, &dummy,
+               if (fastpath(os_atomic_cmpxchgv(&fbh_ring[idx], gen, gen | ref, &dummy,

                                relaxed))) {
                        if (fastpath(os_atomic_cmpxchgv(fbh_ring_head, head, head + 1,
                                        &head, release))) {
                                relaxed))) {
                        if (fastpath(os_atomic_cmpxchgv(fbh_ring_head, head, head + 1,
                                        &head, release))) {


@@ -946,7 +1015,7 @@ firehose_buffer_ring_try_recycle(firehose_buffer_t fb)
 #ifndef KERNEL
 OS_NOINLINE
 static firehose_tracepoint_t
 #ifndef KERNEL
 OS_NOINLINE
 static firehose_tracepoint_t

-firehose_buffer_tracepoint_reserve_slow2(firehose_buffer_t fb,
+firehose_buffer_tracepoint_reserve_wait_for_chunks_from_logd(firehose_buffer_t fb,

                firehose_tracepoint_query_t ask, uint8_t **privptr, uint16_t ref)
 {
        const uint64_t bank_unavail_mask = FIREHOSE_BANK_UNAVAIL_MASK(ask->for_io);
                firehose_tracepoint_query_t ask, uint8_t **privptr, uint16_t ref)
 {
        const uint64_t bank_unavail_mask = FIREHOSE_BANK_UNAVAIL_MASK(ask->for_io);


@@ -960,7 +1029,12 @@ firehose_buffer_tracepoint_reserve_slow2(firehose_buffer_t fb,
                state.fbs_atomic_state =
                                os_atomic_load2o(fbb, fbb_state.fbs_atomic_state, relaxed);
                while ((state.fbs_atomic_state - bank_inc) & bank_unavail_mask) {
                state.fbs_atomic_state =
                                os_atomic_load2o(fbb, fbb_state.fbs_atomic_state, relaxed);
                while ((state.fbs_atomic_state - bank_inc) & bank_unavail_mask) {

-                       firehose_client_send_push(fb, ask->for_io, &state);
+                       if (ask->quarantined) {
+                               __FIREHOSE_CLIENT_THROTTLED_DUE_TO_HEAVY_LOGGING__(fb,
+                                               ask->for_io, &state);
+                       } else {
+                               firehose_client_send_push_and_wait(fb, ask->for_io, &state);
+                       }

                        if (slowpath(fb->fb_header.fbh_sendp == MACH_PORT_DEAD)) {
                                // logd was unloaded, give up
                                return NULL;
                        if (slowpath(fb->fb_header.fbh_sendp == MACH_PORT_DEAD)) {
                                // logd was unloaded, give up
                                return NULL;


@@ -992,7 +1066,12 @@ firehose_buffer_tracepoint_reserve_slow2(firehose_buffer_t fb,
                if (fastpath(ref = firehose_buffer_ring_try_grow(fbb, fbs_max_ref))) {
                        break;
                }
                if (fastpath(ref = firehose_buffer_ring_try_grow(fbb, fbs_max_ref))) {
                        break;
                }

-               firehose_client_send_push(fb, ask->for_io, NULL);
+               if (ask->quarantined) {
+                       __FIREHOSE_CLIENT_THROTTLED_DUE_TO_HEAVY_LOGGING__(fb,
+                                       ask->for_io, &state);
+               } else {
+                       firehose_client_send_push_and_wait(fb, ask->for_io, NULL);
+               }

                if (slowpath(fb->fb_header.fbh_sendp == MACH_PORT_DEAD)) {
                        // logd was unloaded, give up
                        break;
                if (slowpath(fb->fb_header.fbh_sendp == MACH_PORT_DEAD)) {
                        // logd was unloaded, give up
                        break;


@@ -1038,7 +1117,8 @@ firehose_buffer_tracepoint_reserve_slow(firehose_buffer_t fb,
                        }
                }
        }
                        }
                }
        }

-       return firehose_buffer_tracepoint_reserve_slow2(fb, ask, privptr, ref);
+       return firehose_buffer_tracepoint_reserve_wait_for_chunks_from_logd(fb, ask,
+                       privptr, ref);

 #else
        firehose_bank_state_u value;
        ask->is_bank_ok = os_atomic_rmw_loop2o(fbb, fbb_state.fbs_atomic_state,
 #else
        firehose_bank_state_u value;
        ask->is_bank_ok = os_atomic_rmw_loop2o(fbb, fbb_state.fbs_atomic_state,


@@ -1100,7 +1180,7 @@ __firehose_merge_updates(firehose_push_reply_t update)
 {
        firehose_buffer_t fb = kernel_firehose_buffer;
        if (fastpath(fb)) {
 {
        firehose_buffer_t fb = kernel_firehose_buffer;
        if (fastpath(fb)) {

-               firehose_client_merge_updates(fb, true, update, NULL);
+               firehose_client_merge_updates(fb, true, update, false, NULL);

        }
 }
 #endif // KERNEL
        }
 }
 #endif // KERNEL