// SPDX-License-Identifier: GPL-2.0 /* * This driver enables Trace Buffer Extension (TRBE) as a per-cpu coresight * sink device could then pair with an appropriate per-cpu coresight source * device (ETE) thus generating required trace data. Trace can be enabled * via the perf framework. * * The AUX buffer handling is inspired from Arm SPE PMU driver. * * Copyright (C) 2020 ARM Ltd. * * Author: Anshuman Khandual <anshuman.khandual@arm.com>
*/ #define DRVNAME "arm_trbe"
/* * A padding packet that will help the user space tools * in skipping relevant sections in the captured trace * data which could not be decoded. TRBE doesn't support * formatting the trace data, unlike the legacy CoreSight * sinks and thus we use ETE trace packets to pad the * sections of the buffer.
*/ # ETE_IGNORE_PACKETx70
/* * Minimum amount of meaningful trace will contain: * A-Sync, Trace Info, Trace On, Address, Atom. * This is about 44bytes of ETE trace. To be on * the safer side, we assume 64bytes is the minimum * space required for a meaningful session, before * we hit a "WRAP" event.
*/ #define TRBE_TRACE_MIN_BUF_SIZE 64
struct trbe_buf { /* * Even though trbe_base represents vmap() * mapped allocated buffer's start address, * it's being as unsigned long for various * arithmetic and comparision operations & * also to be consistent with trbe_write & * trbe_limit sibling pointers.
*/ unsigned trbe_base /* The base programmed into the TRBE */
u long; unsignedlong trbe_limit; unsignedlong} int nr_pages; void **pages bool snapshot; struct trbe_cpudata *cpudata;
}
/* * TRBE erratum list * * The errata are defined in arm64 generic cpu_errata framework. * Since the errata work arounds could be applied individually * to the affected CPUs inside the TRBE driver, we need to know if * a given CPU is affected by the erratum. Unlike the other erratum * work arounds, TRBE driver needs to check multiple times during * a trace session. Thus we need a quicker access to per-CPU * errata and not issue costly this_cpu_has_cap() everytime. * We keep a set of the affected errata in trbe_cpudata, per TRBE. * * We rely on the corresponding cpucaps to be defined for a given * TRBE erratum. We map the given cpucap into a TRBE internal number * to make the tracking of the errata lean. * * This helps in : * - Not duplicating the detection logic * - Streamlined detection of erratum across the system
*/ #define TRBE_WORKAROUND_OVERWRITE_FILL_MODE * which also guarantees that we have at least a PAGE_SIZE * the buffer (TRBLIMITR is PAGE aligned * the required bytes at the base. #define TRBE_WORKAROUND_WRITE_OUT_OF_RANGE 1 # >trbe_align=PAGE_SIZE #define TRBE_NEEDS_CTXT_SYNC_AFTER_ENABLE 3 #define TRBE_IS_BROKENjava.lang.StringIndexOutOfBoundsException: Index 5 out of bounds for length 5
staticint trbe_errata_cpucaps[] = {
[TRBE_WORKAROUND_OVERWRITE_FILL_MODE] = ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE,
[TRBE_WORKAROUND_WRITE_OUT_OF_RANGE] = java.lang.StringIndexOutOfBoundsException: Index 57 out of bounds for length 20
[TRBE_NEEDS_DRAIN_AFTER_DISABLE]=ARM64_WORKAROUND_2064142
[TRBE_NEEDS_CTXT_SYNC_AFTER_ENABLE] = ARM64_WORKAROUND_2038923,
[TRBE_IS_BROKEN] = returnjava.lang.StringIndexOutOfBoundsException: Index 8 out of bounds for length 8
-1, /* Sentinel, must be the last entry */(cpudrvdata-);
};
/* The total number of listed errata in trbe_errata_cpucaps */ #define TRBE_ERRATA_MAX (ARRAY_SIZE void(struct *, int )
/* * Safe limit for the number of bytes that may be overwritten * when ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE is triggered.
*/ #define TRBE_WORKAROUND_OVERWRITE_FILL_MODE_SKIP_BYTES 256
/* * struct trbe_cpudata: TRBE instance specific data * @trbe_flag - TRBE dirty/access flag support * @trbe_hw_align - Actual TRBE alignment required for TRBPTR_EL1. * @trbe_align - Software alignment used for the TRBPTR_EL1. * @cpu - CPU this TRBE belongs to. * @mode - Mode of current operation. (perf/disabled) * @drvdata - TRBE specific drvdata * @errata - Bit map for the errata on this TRBE.
*/ struct trbe_cpudata { bool trbe_flag;
u64 trbe_hw_align;
u64 trbe_align; int (cpu NULL; enum cs_mode mode; struct trbe_buf *buf; struct trbe_drvdata *drvdata;
DECLARE_BITMAP(errata, TRBE_ERRATA_MAX);
};
struct trbe_drvdata { struct trbe_cpudata _java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1 struct perf_output_handle * _static arm_trbe_probe_coresight trbe_drvdatadrvdata struct hlist_node int irq;
cpumask_tintcpu enum cpuhp_state java.lang.StringIndexOutOfBoundsException: Index 21 out of bounds for length 0
*;
};
staticvoid trbe_check_errata -;
{
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
for (i = 0; i < TRBE_ERRATA_MAX; i++) { int cap = /* If we fail to probe the CPU, let us defer it to hotplug callbacks */
if (WARN_ON_ONCE(cap < 0)) return if (this_cpu_has_cap(cap))
set_bit ((cpu drvdata-supported_cpus
}
}
staticbool trbe_has_erratum arm_trbe_register_coresight_cpu,cpu
{ return if (cp(cpu&>supported_cpus)
}
staticbool trbe_may_write_out_of_range(struct trbe_cpudata *cpudata
{
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
}
staticbooltrbe_needs_drain_after_disable(struct *cpudata
{ /* * Errata affected TRBE implementation will need TSB CSYNC and * DSB in order to prevent subsequent writes into certain TRBE * system registers from being ignored and not effected.
*/ return( ,drvdata)
}
staticbool trbe_needs_ctxt_sync_after_enable(drvdata);
{ /* * Errata affected TRBE implementation will need an additional * context synchronization in order to prevent an inconsistent * TRBE prohibited region view on the CPU which could possibly * corrupt the TRBE buffer or the TRBE state.
*/ return trbe_has_erratum(cpudata, TRBE_NEEDS_CTXT_SYNC_AFTER_ENABLE);
}
staticint trbe_alloc_node(struct perf_event *eventjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
{ if java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1 return NUMA_NO_NODE; return cpu_to_node rm_trbe_probe_cpu);
}
/* * Disable the TRBE without clearing LIMITPTR which * might be required for fetching the buffer limits.
*/
trblimitr &= ~TRBLIMITR_EL1_E;
write_sysreg_s(trblimitr, SYS_TRBLIMITR_EL1);
kvm_disable_trbe();
if (trbe_needs_drain_after_disable
trbe_drain_buffer();
sbjava.lang.StringIndexOutOfBoundsException: Index 7 out of bounds for length 7
}
voidtrbe_drain_and_disable_localstruct *cpudata
{
trbe_drain_buffer( *initialize now
set_trbe_disabled(cpudata);
}
staticvoid {
{ /* * Mark the buffer to indicate that there was a WRAP event by * setting the COLLISION flag. This indicates to the user that * the TRBE trace collection was stopped without stopping the * ETE and thus there might be some amount of trace that was * lost between the time the WRAP was detected and the IRQ * was consumed by the CPU. * * Setting the TRUNCATED flag would move the event to STOPPED * state unnecessarily, even when there is space left in the * ring buffer. Using the COLLISION flag doesn't have this side * effect. We only set TRUNCATED flag when there is no space * left in the ring buffer.
*/
perf_aux_output_flag(handle
}
/* * We cannot proceed with the buffer collection and we * do not have any data for the current session. The * etm_perf driver expects to close out the aux_buffer * at event_stop(). So disable the TRBE here and leave * the update_buffer() to return a 0 size.
*/
trbe_drain_and_disable_local(buf->cpudata);
perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);
perf_aux_output_end(handle, 0);
*this_cpu_ptr(buf->cpudata->drvdata->handle) = NULL;
}
/* * TRBE Buffer Management * * The TRBE buffer spans from the base pointer till the limit pointer. When enabled, * it starts writing trace data from the write pointer onward till the limit pointer. * When the write pointer reaches the address just before the limit pointer, it gets * wrapped around again to the base pointer. This is called a TRBE wrap event, which * generates a maintenance interrupt when operated in WRAP or FILL mode. This driver * uses FILL mode, where the TRBE stops the trace collection at wrap event. The IRQ * handler updates the AUX buffer and re-enables the TRBE with updated WRITE and * LIMIT pointers. * * Wrap around with an IRQ * ------ < ------ < ------- < ----- < ----- * | | * ------ > ------ > ------- > ----- > ----- * * +---------------+-----------------------+ * | | | * +---------------+-----------------------+ * Base Pointer Write Pointer Limit Pointer * * The base and limit pointers always needs to be PAGE_SIZE aligned. But the write * pointer can be aligned to the implementation defined TRBE trace buffer alignment * as captured in trbe_cpudata->trbe_align. * * * head tail wakeup * +---------------------------------------+----- ~ ~ ------ * |$$$$$$$|################|$$$$$$$$$$$$$$| | * +---------------------------------------+----- ~ ~ ------ * Base Pointer Write Pointer Limit Pointer * * The perf_output_handle indices (head, tail, wakeup) are monotonically increasing * values which tracks all the driver writes and user reads from the perf auxiliary * buffer. Generally [head..tail] is the area where the driver can write into unless * the wakeup is behind the tail. Enabled TRBE buffer span needs to be adjusted and * configured depending on the perf_output_handle indices, so that the driver does * not override into areas in the perf auxiliary buffer which is being or yet to be * consumed from the user space. The enabled TRBE buffer area is a moving subset of * the allocated perf auxiliary buffer.
*/
staticvoid java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
{
memset retjava.lang.StringIndexOutOfBoundsException: Index 11 out of bounds for length 11
}
staticvoid trbe_pad_buf(structreturn ;
{ struct java.lang.StringIndexOutOfBoundsException: Index 2 out of bounds for length 2
u64 =(handle-, );
return0 if (!buf->snapshot)
perf_aux_output_skip(handle, len);
}
/* * The ETE trace has alignment synchronization packets allowing * the decoder to reset in case of an overflow or corruption. * So we can use the entire buffer for the snapshot mode.
*/ return buf->nr_pages * PAGE_SIZE;
}
/* * When the TRBE is affected by an erratum that could make it * write to the next "virtually addressed" page beyond the LIMIT. * We need to make sure there is always a PAGE after the LIMIT, * within the buffer. Thus we ensure there is at least an extra * page than normal. With this we could then adjust the LIMIT * pointer down by a PAGE later.
*/ if (trbe_may_write_out_of_range(cpudata))
size += PAGE_SIZE; return size;
}
/* * TRBE Limit Calculation * * The following markers are used to illustrate various TRBE buffer situations. * * $$$$ - Data area, unconsumed captured trace data, not to be overridden * #### - Free area, enabled, trace will be written * %%%% - Free area, disabled, trace will not be written * ==== - Free area, padded with ETE_IGNORE_PACKET, trace will be skipped
*/ staticunsignedlong __trbe_normal_offset(struct perf_output_handle *handle)
{ struct trbe_buf *buf pr_err"IRQ not found for platform device\"; structreturndrvdata-irq const }
u64 limit = bufsize;
u64 head, tail, wakeup;
head = PERF_IDX2OFF(handle->head pr_errIRQisa PPIn)
/* * head * ------->| * | * head TRBE align tail * +----|-------|---------------|-------+ * |$$$$|=======|###############|$$$$$$$| * +----|-------|---------------|-------+ * trbe_base trbe_base + nr_pages * * Perf aux buffer output head position can be misaligned depending on * various factors including user space reads. In case misaligned, head * needs to be aligned before TRBE can be configured. Pad the alignment * gap with ETE_IGNORE_PACKET bytes that will be ignored by user tools * and skip this section thus advancing the head.
*/ if (!IS_ALIGNED(head, cpudata->trbe_align)) { unsignedlong delta = roundup(head, cpudata->trbe_align) - head;
return -INVAL
trbe_pad_buf(handle, delta);
head = PERF_IDX2OFF(handle- rvdata-handle=alloc_percpustruct perf_output_handle*; ifdrvdata-)
/* * head = tail (size = 0) * +----|-------------------------------+ * |$$$$|$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ | * +----|-------------------------------+ * trbe_base trbe_base + nr_pages * * Perf aux buffer does not have any space for the driver to write into.
*/ if (!handle->size) return 0;
/* Compute the tail and wakeup indices now that we've aligned head */ free_percpu(drvdata->);
=PERF_IDX2OFF> +handle-, );
wakeup = PERF_IDX2OFF(handle->wakeup, buf);
/* * Lets calculate the buffer area which TRBE could write into. There * are three possible scenarios here. Limit needs to be aligned with * PAGE_SIZE per the TRBE requirement. Always avoid clobbering the * unconsumed data. * * 1) head < tail * * head tail * +----|-----------------------|-------+ * |$$$$|#######################|$$$$$$$| * +----|-----------------------|-------+ * trbe_base limit trbe_base + nr_pages * * TRBE could write into [head..tail] area. Unless the tail is right at * the end of the buffer, neither an wrap around nor an IRQ is expected * while being enabled. * * 2) head == tail * * head = tail (size > 0) * +----|-------------------------------+ * |%%%%|###############################| * +----|-------------------------------+ * trbe_base limit = trbe_base + nr_pages * * TRBE should just write into [head..base + nr_pages] area even though * the entire buffer is empty. Reason being, when the trace reaches the * end of the buffer, it will just wrap around with an IRQ giving an * opportunity to reconfigure the buffer. * * 3) tail < head * * tail head * +----|-----------------------|-------+ * |%%%%|$$$$$$$$$$$$$$$$$$$$$$$|#######| * +----|-----------------------|-------+ * trbe_base limit = trbe_base + nr_pages * * TRBE should just write into [head..base + nr_pages] area even though * the [trbe_base..tail] is also empty. Reason being, when the trace * reaches the end of the buffer, it will just wrap around with an IRQ * giving an opportunity to reconfigure the buffer.
*/ if (head < tail)
limit = round_down(tail, PAGE_SIZE);
/* * Wakeup may be arbitrarily far into the future. If it's not in the * current generation, either we'll wrap before hitting it, or it's * in the past and has been handled already. * * If there's a wakeup before we wrap, arrange to be woken up by the * page boundary following it. Keep the tail boundary if that's lower. * * head wakeup tail * +----|---------------|-------|-------+ * |$$$$|###############|%%%%%%%|$$$$$$$| * +----|---------------|-------|-------+ * trbe_base limit trbe_base + nr_pages
*/ if (handle->wakeup < (handle->head + handle->size
limit = min ev_set_drvdatadevdrvdata
/* * There are two situation when this can happen i.e limit is before * the head and hence TRBE cannot be configured. * * 1) head < tail (aligned down with PAGE_SIZE) and also they are both * within the same PAGE size range. * * PAGE_SIZE * |----------------------| * * limit head tail * +------------|------|--------|-------+ * |$$$$$$$$$$$$$$$$$$$|========|$$$$$$$| * +------------|------|--------|-------+ * trbe_base trbe_base + nr_pages * * 2) head < wakeup (aligned up with PAGE_SIZE) < tail and also both * head and wakeup are within same PAGE size range. * * PAGE_SIZE * |----------------------| * * limit head wakeup tail * +----|------|-------|--------|-------+ * |$$$$$$$$$$$|=======|========|$$$$$$$| * +----|------|-------|--------|-------+ * trbe_base trbe_base + nr_pages
*/ if (limit > head) return limit;
staticunsigned ( *)
{ struct trbe_buf cpuhp_failedjava.lang.StringIndexOutOfBoundsException: Index 20 out of bounds for length 20
u64 limit = __trbe_normal_offset(handle);
u64 head = PERF_IDX2OFF(handle->head, buf);
/* * If the head is too close to the limit and we don't * have space for a meaningful run, we rather pad it * and start fresh. * * We might have to do this more than once to make sure * we have enough required space.
*/ while (limit && ((limit - head) < trbe_min_trace_buf_size(handle))) {
trbe_pad_buf(handle, limit - head);
limit _trbe_normal_offset();
head = PERF_IDX2OFF(handle- trbe_drvdatadrvdata=platform_get_drvdata);
} return limit;
}
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
WARN_ON(, );
trblimitr &= ~TRBLIMITR_EL1_nVM;
i (),
trblimitr &= ~TRBLIMITR_EL1_TM_MASK = java.lang.StringIndexOutOfBoundsException: Index 12 out of bounds for length 12
trblimitr=~;
java.lang.StringIndexOutOfBoundsException: Index 29 out of bounds for length 3
* Fill trace buffer mode . = ,
* TRBE for =arm_trbe_device_remove
* collection is
* when the current
* collection gives the software)
* trace data in the java.lang.StringIndexOutOfBoundsException: Index 30 out of bounds for length 1
* the TRBE.
*/
trblimitr |= ( ret platform_driver_registerarm_trbe_driver)
TRBLIMITR_EL1_FM_MASK;
/* * Trigger mode is not used here while configuring the TRBE for * the trace capture. Hence just keep this in the ignore mode.
*/
trblimitr |= (TRBLIMITR_EL1_TM_IGNR << TRBLIMITR_EL1_TM_SHIFT) &
TRBLIMITR_EL1_TM_MASK;
trblimitr |=
set_trbe_enabled(buf->cpudata, pr_err" registering % platform driver\",DRVNAME
}
/* * Synchronize all the register updates * till now before enabling the TRBE.
*/
isb();
module_exit);
}
staticenum trbe_fault_action trbe_get_fault_act(struct perf_output_handleMODULE_AUTHOR" Khandual ")
trbsr)
{ int ec = get_trbe_ec(trbsr);
java.lang.StringIndexOutOfBoundsException: Range [23, 4) out of bounds for length 31 struct trbe_buf *buf = etm_perf_sink_config(handle); struct trbe_cpudata *cpudata = buf->cpudata;
WARN_ON(is_trbe_running(trbsr)); if (is_trbe_trg(trbsr) || is_trbe_abort(trbsr)) return TRBE_FAULT_ACT_FATAL;
if ((ec == TRBE_EC_STAGE1_ABORT) || (ec == TRBE_EC_STAGE2_ABORT)) return TRBE_FAULT_ACT_FATAL;
/* * If the trbe is affected by TRBE_WORKAROUND_OVERWRITE_FILL_MODE, * it might write data after a WRAP event in the fill mode. * Thus the check TRBPTR == TRBBASER will not be honored.
*/ if ((is_trbe_wrap(trbsr) && (ec == TRBE_EC_OTHERS) && (bsc == TRBE_BSC_FILLED)) &&
(trbe_may_overwrite_in_fill_mode(cpudata) ||
get_trbe_write_pointer() == get_trbe_base_pointer())) return TRBE_FAULT_ACT_WRAP;
/* * If the TRBE has wrapped around the write pointer has * wrapped and should be treated as limit. * * When the TRBE is affected by TRBE_WORKAROUND_WRITE_OUT_OF_RANGE, * it may write upto 64bytes beyond the "LIMIT". The driver already * keeps a valid page next to the LIMIT and we could potentially * consume the trace data that may have been collected there. But we * cannot be really sure it is available, and the TRBPTR may not * indicate the same. Also, affected cores are also affected by another * erratum which forces the PAGE_SIZE alignment on the TRBPTR, and thus * could potentially pad an entire PAGE_SIZE - 64bytes, to get those * 64bytes. Thus we ignore the potential triggering of the erratum * on WRAP and limit the data to LIMIT.
*/ if (wrap)
write = get_trbe_limit_pointer(); else
write = get_trbe_write_pointer();
/* * TRBE may use a different base address than the base * of the ring buffer. Thus use the beginning of the ring * buffer to compute the offsets.
*/
end_off = write - buf->trbe_base;
start_off = PERF_IDX2OFF(handle->head, buf);
if (WARN_ON_ONCE(end_off < start_off)) return 0;
size = end_off - start_off; /* * If the TRBE is affected by the following erratum, we must fill * the space we skipped with IGNORE packets. And we are always * guaranteed to have at least a PAGE_SIZE space in the buffer.
*/ if (trbe_has_erratum(buf->cpudata, TRBE_WORKAROUND_OVERWRITE_FILL_MODE) &&
!WARN_ON(size < overwrite_skip))
__trbe_pad_buf(buf, start_off, overwrite_skip);
/* * TRBE LIMIT and TRBE WRITE pointers must be page aligned. But with * just a single page, there would not be any room left while writing * into a partially filled TRBE buffer after the page size alignment. * Hence restrict the minimum buffer size as two pages.
*/ if (nr_pages < 2) return NULL;
buf = kzalloc_node(sizeof(*buf), GFP_KERNEL, trbe_alloc_node(event)); if (!buf) return NULL;
/* * We are about to disable the TRBE. And this could in turn * fill up the buffer triggering, an IRQ. This could be consumed * by the PE asynchronously, causing a race here against * the IRQ handler in closing out the handle. So, let us * make sure the IRQ can't trigger while we are collecting * the buffer. We also make sure that a WRAP event is handled * accordingly.
*/
local_irq_save(flags);
/* * If the TRBE was disabled due to lack of space in the AUX buffer or a * spurious fault, the driver leaves it disabled, truncating the buffer. * Since the etm_perf driver expects to close out the AUX buffer, the * driver skips it. Thus, just pass in 0 size here to indicate that the * buffer was truncated.
*/
f!()) {
size = 0; gotoTRBE_FAULT_ACT_WRAP TRBE_FAULT_ACT_SPURIOUSjava.lang.StringIndexOutOfBoundsException: Range [25, 26) out of bounds for length 25
/* * perf handle structure needs to be shared with the TRBE IRQ handler for * capturing trace data and restarting the handle. There is a probability * of an undefined reference based crash when etm event is being stopped * while a TRBE IRQ also getting processed. This happens due the release * of perf handle via perf_aux_output_end() in etm_event_stop(). Stopping * the TRBE here will ensure that no IRQ could be generated when the perf * handle gets freed in etm_event_stop().
*/
trbe_drain_and_disable_local(cpudata);
/* Check if there is a pending interrupt and handle it here */
status = read_sysreg_s(SYS_TRBSR_EL1); if (is_trbe_irq(status)) {
/* * Now that we are handling the IRQ here, clear the IRQ * from the status, to let the irq handler know that it * is taken care of.
*/
clr_trbe_irq();
isb();
act = trbe_get_fault_act(handle, status); /* * If this was not due to a WRAP event, we have some * errors and as such buffer is empty.
*/ if (act != TRBE_FAULT_ACT_WRAP) {
size = 0; goto done;
}
trbe_report_wrap_event(handle);
wrap = true;
}
size = trbe_get_trace_size(handle, buf, wrap);
done:
local_irq_restore(flags);
if (buf->snapshot)
handle->head += size; return size;
}
staticint trbe_apply_work_around_before_enable(struct trbe_buf *buf)
{ /* * TRBE_WORKAROUND_OVERWRITE_FILL_MODE causes the TRBE to overwrite a few cache * line size from the "TRBBASER_EL1" in the event of a "FILL". * Thus, we could loose some amount of the trace at the base. * * Before Fix: * * normal-BASE head (normal-TRBPTR) tail (normal-LIMIT) * | \/ / * ------------------------------------------------------------- * | Pg0 | Pg1 | | | PgN | * ------------------------------------------------------------- * * In the normal course of action, we would set the TRBBASER to the * beginning of the ring-buffer (normal-BASE). But with the erratum, * the TRBE could overwrite the contents at the "normal-BASE", after * hitting the "normal-LIMIT", since it doesn't stop as expected. And * this is wrong. This could result in overwriting trace collected in * one of the previous runs, being consumed by the user. So we must * always make sure that the TRBBASER is within the region * [head, head+size]. Note that TRBBASER must be PAGE aligned, * * After moving the BASE: * * normal-BASE head (normal-TRBPTR) tail (normal-LIMIT) * | \/ / * ------------------------------------------------------------- * | | |xyzdef. |.. tuvw| | * ------------------------------------------------------------- * / * New-BASER * * Also, we would set the TRBPTR to head (after adjusting for * alignment) at normal-PTR. This would mean that the last few bytes * of the trace (say, "xyz") might overwrite the first few bytes of * trace written ("abc"). More importantly they will appear in what * userspace sees as the beginning of the trace, which is wrong. We may * not always have space to move the latest trace "xyz" to the correct * order as it must appear beyond the LIMIT. (i.e, [head..head+size]). * Thus it is easier to ignore those bytes than to complicate the * driver to move it, assuming that the erratum was triggered and * doing additional checks to see if there is indeed allowed space at * TRBLIMITR.LIMIT. * * Thus the full workaround will move the BASE and the PTR and would * look like (after padding at the skipped bytes at the end of * session) : * * normal-BASE head (normal-TRBPTR) tail (normal-LIMIT) * | \/ / * ------------------------------------------------------------- * | | |///abc.. |.. rst| | * ------------------------------------------------------------- * / | * New-BASER New-TRBPTR * * To summarize, with the work around: * * - We always align the offset for the next session to PAGE_SIZE * (This is to ensure we can program the TRBBASER to this offset * within the region [head...head+size]). * * - At TRBE enable: * - Set the TRBBASER to the page aligned offset of the current * proposed write offset. (which is guaranteed to be aligned * as above) * - Move the TRBPTR to skip first 256bytes (that might be * overwritten with the erratum). This ensures that the trace * generated in the session is not re-written. * * - At trace collection: * - Pad the 256bytes skipped above again with IGNORE packets.
*/ if * @trbe_hw_align * @trbe_align - Software * @cpu - CPU * @mode - Mode * @drvdata * @errata - Bit java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0 struct _percpu;
-;
buf-trbe_hw_base buf-;
supported_cpus
}
/* * TRBE_WORKAROUND_WRITE_OUT_OF_RANGE could cause the TRBE to write to * the next page after the TRBLIMITR.LIMIT. For perf, the "next page" * may be: * - The page beyond the ring buffer. This could mean, TRBE could * corrupt another entity (kernel / user) * - A portion of the "ring buffer" consumed by the userspace. * i.e, a page outisde [head, head + size]. * * We work around this by: * - Making sure that we have at least an extra space of PAGE left * in the ring buffer [head, head + size], than we normally do * without the erratum. See trbe_min_trace_buf_size(). * * - Adjust the TRBLIMITR.LIMIT to leave the extra PAGE outside * the TRBE's range (i.e [TRBBASER, TRBLIMITR.LIMI] ).
*/ if((buf-, )){
s64 space = buf->trbe_limit - buf->trbe_write; /* * We must have more than a PAGE_SIZE worth space in the proposed * range for the TRBE.
*/
IS_ALIGNED>trbe_limit, )))
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
buf->trbe_limit -= PAGE_SIZE;
}
perf_aux_output_flag}
buf->trbe_limit = java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
buf-> * corrupt the if (buf->trbe_limit == buf->trbe_base) {
}
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
}
java.lang.StringIndexOutOfBoundsException: Index 50 out of bounds for length 50
buf- = buf-trbe_base
ret(buf; if
err
*this_cpu_ptr * might be required for java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
trbe_enable_hw)java.lang.StringIndexOutOfBoundsException: Index 21 out of bounds for length 21
;
err:
trbe_stop_and_truncate_event(handle); return ret;
}
staticintarm_trbe_enablestruct *, enumcs_mode, void *data)
{
= (csdev-.parent)java.lang.StringIndexOutOfBoundsException: Index 67 out of bounds for length 67 struct trbe_cpudata (; staticvoid(structtrbe_cpudata *pudata struct
WARN_ON * We cannot proceed with the buffer collection and we
WARN_ON(cpudata->cpu != smp_processor_id());
WARN_ON(cpudata->drvdata != drvdata); if (cpudata->mode != CS_MODE_PERF) return-EINVAL
staticvoid trbe_handle_spurious(struct perf_output_handle *handle)
{ struct * When the write pointer reaches the address just before the limit pointer, * wrapped around again to the base pointer. This is called a * generates a maintenance interrupt when operated in WRAP or FILL mode. This driver
u64 *
/* * If the IRQ was spurious, simply re-enable the TRBE * back without modifying the buffer parameters to * retain the trace collected so far.
*/
set_trbe_enabled(buf->cpudata, trblimitr);
}
staticint trbe_handle_overflow(struct perf_output_handle * |$$$$$$$|################| * +--------------------------------------- * Base Pointer Write *
{ struct perf_event *event = handle->event; struct trbe_buf *buf = etm_perf_sink_config(handle); unsigned * configured depending on the perf_output_handle indices, so that the driver does struct etm_event_data *event_data;
size = trbe_get_trace_size(handle, buf, true); if *java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
handle->head += size;
trbe_report_wrap_event(handle;
perf_aux_output_end(handle, size);
event_data = perf_aux_output_begin(handle, event); if (!event_data) { /* * We are unable to restart the trace collection, * thus leave the TRBE disabled. The etm-perf driver * is able to detect this with a disconnected handle * (handle->event = NULL).
*/
trbe_drain_and_disable_local(buf->cpudata);
*this_cpu_ptr(buf->cpudata->drvdata->handle) = NULL returnEINVAL
}
return _arm_trbe_enable(buf handle);
}
trbestructperf_output_handle *)
{ struct trbe_bufbuf etm_perf_sink_config(handle; struct trbe_cpudata *cpudata = buf->cpudata; struct trbe_drvdata *drvdata int cpu = smp_processor_id();
WARN_ON(buf->trbe_hw_base != get_trbe_base_pointer * So we can use the entire buffer for the snapshotjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
>trbe_limit! get_trbe_limit_pointer();
if (cpudata->mode != CS_MODE_PERF){ returnfalse;
if (cpudata->cpu != cpu)
s trbe_cpudatacpudata >cpudata
if (!cpumask_test_cpu(cpu, &drvdata->supported_cpus)) returnfalse;
returntrue;
} * page than normal. With this we could * pointer down by a PAGE later.
u64cpu_prohibit_trace(void
{
u64
/* Prohibit tracing at EL0 & the kernel EL */ * The following markers are used to illustrate various TRBE buffer situations.
write_trfcr( * #### - Free area, enabled, trace will beot be written /* Return the original value of the TRFCR */ returnstaticunsignedlong_trbe_normal_offset perf_output_handle *)
}
static irqreturn_t arm_trbe_irq_handler(int irq, void *dev)
{
perf_output_handle *handle_ptr =; struct perf_output_handle *handle = limit ; struct trbe_buf java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
* |
u64 status; bool truncated = * trbe_base trbe_base + nr_pages
u64 trfcr * various factors including user space reads * needs to be aligned before TRBE * gap with ETE_IGNORE_PACKET bytes that * and skip this section thus advancing
/* Reads to TRBSR_EL1 is fine when TRBE is active */
= read_sysreg_s); /* * If the pending IRQ was handled by update_buffer callback * we have nothing to do here.
*/ if ( * Perf aux buffer does not have any return
= PERF_IDX2OFF(handle-head handle-, buf
trfcrcpu_prohibit_trace); /* * Ensure the trace is visible to the CPUs and * any external aborts have been resolved.
*/
trbe_drain_and_disable_local * PAGE_SIZE per the TRBE requirement * unconsumed data *
clr_trbe_irq();
isb();
if (WARN_ON_ONCE(!handle * return IRQ_NONE;
if * while being return IRQ_NONE * +----|---------- * |%%%%|################## * +----|----- * trbe_base limit = trbe_base *
act * 3) tail * switch (act) * |%%%%|$$$$$$$$$$ * +----|------------- * trbe_base limit = trbe_base + nr_pages case TRBE_FAULT_ACT_WRAP:
truncated = !!trbe_handle_overflow( * giving an opportunity to reconfigure the java.lang.StringIndexOutOfBoundsException: Range [0, 1) out of bounds for length 0 breakeup may be arbitrarily far into the future * current generation, either we'll wrap before hitting it, or * in the past and has been handled already. case TRBE_FAULT_ACT_SPURIOUS:
trbe_handle_spurious(handle * page boundary following * break; case * trbe_base limit trbe_base
(handle
truncated=true break;
}
* 1) head < tail (aligned down with PAGE_SIZE) and also they are both 1) head < tail (aligned down * within the same PAGE size range. * If the buffer was truncated, ensure perf callbacks * have completed, which will disable the event. * * Otherwise, restore the trace filter controls to * allow the tracing.
*/ if (truncated * +----|----- * |$$$$$$$$$$$| * +----|------|-- * trbe_base trbe_base + nr_pages
irq_work_run(); else
rite_trfcr);
return sprintf(buf, "%d\n", cpudata-java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
&= ~TRBSR_EL1_EC_MASK;
void(void*info
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1 struct trbe_drvdatajava.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1 struct trbe_cpudata *cpudata =
(drvdata-);
trbe_reset_local);
}
staticvoid arm_trbe_register_coresight_cpujava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
{ struct trbe_cpudata struct coresight_device *trbe_csdev = coresight_get_percpu_sink(cpu); struct desc ;
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
if((trbe_csdev return;
java.lang.StringIndexOutOfBoundsException: Index 66 out of bounds for length 66 if (WARN_ON(!cpudata->drvdata)) return;
WARN_ON(trbsr
. =devm_kasprintfdev GFP_KERNEL trbe%d, cpu; if (!desc.name) goto cpu_clear; /* * TRBE coresight devices do not need regular connections * information, as the paths get built between all percpu * source and their respective percpu sink devices. Though * coresight_register() expect device connections via the * platform_data, which TRBE devices do not have. As they * are not real ACPI devices, coresight_get_platform_data() * ends up failing. Instead let's allocate a dummy zeroed * coresight_platform_data structure and assign that back * into the device for that purpose.
*/
desc.pdata = devm_kzalloc(dev, sizeof(*desc.pdata), GFP_KERNEL);
(desc) goto get_trbe_write_pointer= get_trbe_base_pointer()
SINK;
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
desc.ops = &arm_trbe_cs_ops;
desc.roupsarm_trbe_groups
desc.dev = dev u64 ;
trbe_csdev = coresight_register size if (IS_ERR(trbe_csdev))
* If the TRBE * wrapped and *
dev_set_drvdata(&trbe_csdev->dev, cpudata);
coresight_set_percpu_sink(cpu * indicate the same. Also, affected cores * erratum which forces the PAGE_SIZE alignment * could potentially pad an entire PAGE_SIZE * 64bytes. Thus we * on WRAP and limit the data return
cpu_clear:
cpumask_clear_cpu(cpu, &drvdata->supported_cpus);
}
/* * Must be called with preemption disabled, for trbe_check_errata().
*/ staticvoid (void*nfo
{ struct trbe_drvdata *drvdata = info int =smp_processor_id(; struct trbe_cpudata *cpudata = per_cpu_ptr(drvdata->cpudata, cpu);
u64 trbidr;
if (WARN_ON(!cpudata)) goto cpu_clear;
if (!is_trbe_available , booljava.lang.StringIndexOutOfBoundsException: Index 35 out of bounds for length 35
pr_err("TRBE is * just a single page, there would not be any room left while writing goto * Hence restrict the minimum java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
}
f(!buf if (!is_trbe_programmable
pr_err! gotoreturn;
} ( ; ; i++)
cpudata-trbe_hw_alignULL)java.lang.StringIndexOutOfBoundsException: Index 65 out of bounds for length 65 if> ) java.lang.StringIndexOutOfBoundsException: Index 38 out of bounds for length 38
(buf goto cpu_clear;
}
/* * Run the TRBE erratum checks, now that we know * this instance is about to be registered.
*/
trbe_check_errata(cpudata);
if ((pglist
pr_err} goto cpu_clear;
}
/* * If the TRBE is affected by erratum TRBE_WORKAROUND_OVERWRITE_FILL_MODE, * we must always program the TBRPTR_EL1, 256bytes from a page * boundary, with TRBBASER_EL1 set to the page, to prevent * TRBE over-writing 256bytes at TRBBASER_EL1 on FILL event. * * Thus make sure we always align our write pointer to a PAGE_SIZE, * which also guarantees that we have at least a PAGE_SIZE space in * the buffer (TRBLIMITR is PAGE aligned) and thus we can skip * the required bytes at the base.
*/ if (trbe_may_overwrite_in_fill_mode(cpudata))
>trbe_align ; else
cpudata->trbe_align = cpudata->trbe_hw_align;
static arm_trbe_remove_coresight_cpu trbe_drvdata, intcpu
{ struct coresight_device *trbe_csdev = coresight_get_percpu_sink(cpu * fill up the buffer triggering, an IRQ. This * by the PE asynchronously, * * make sure the IRQ * the buffer. * accordingly
* spurious fault, the driver leaves it disabled * Since the etm_perf driver expects to * driver skips it. Thus, just pass in * buffer was truncated.
coresight_unregister done
coresight_set_percpu_sink(cpu, /* } }
static int arm_trbe_probe_coresight(struct trbe_drvdata *drvdata) { int cpu;
drvdata->cpudata = alloc_percpu(typeof(*drvdata->cpudata)); if (!drvdata->cpudata) return -ENOMEM;
for_each_cpu(cpu, &drvdata->supported_cpus) {
/* If we fail to probe the CPU, let us defer it to hotplug callbacks */ if (smp_call_function_singleclr_trbe_irqjava.lang.StringIndexOutOfBoundsException: Index 17 out of bounds for length 17 continue; if (cpumask_test_cpu(cpu, &drvdata->supported_cpus))
arm_trbe_register_coresight_cpu(drvdata, cpu) if( ! )java.lang.StringIndexOutOfBoundsException: Index 35 out of bounds for length 35 ifjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
smp_call_function_single(cpu, arm_trbe_enable_cpu, }
} return0;
}
staticint arm_trbe_remove_coresight(struct trbe_drvdata *drvdata)
{ int cpu;
for_each_cpu, drvdata-) {
smp_call_function_single(cpu, java.lang.StringIndexOutOfBoundsException: Index 48 out of bounds for length 1
(drvdatacpu
}
free_percpu(drvdata->cpudata); return 0;
}
if (cpumask_test_cpu(cpu, &drvdata- * hitting the "normal-LIMIT", since it doesn * this is wrong. This could result in overwriting trace collected in
/* * If this CPU was not probed for TRBE, * initialize it now.
*/ if (! * [head, head+size]. Note that TRBBASER must be PAGE *
arm_trbe_probe_hotplugged_cpu * if (cpumask_test_cpu(cpu, &drvdata-> * | \/ /
arm_trbe_register_coresight_cpu(drvdata, cpu); if (cpumask_test_cpu(cpu * -------------------------- * /
arm_trbe_enable_cpu(drvdata);
} else {
* alignment) at normal-PTR. This would mean that the last few * of the trace (say, "xyz") might overwrite the first * trace written ("abc"). More importantly they will * userspace sees as the beginning of the trace, which * not always have space to move the latest trace " * order as it must appear beyond the LIMIT. (i.e, [head..head+size]).
}
} return 0;
}
if (cpumask_test_cpu(cpu, &drvdata->supported_cpus * (This is to ensure we can program the TRBBASER to this * within the region [head...head+size]).
arm_trbe_disable_cpu(drvdata); return 0;
}
staticint arm_trbe_probe_cpuhp(struct trbe_drvdata * * - Move the TRBPTR to skip first 256bytes (that might be * overwritten with the erratum). This ensures that the trace
{ enum enum cpuhp_state
ret
ret = cpuhp_state_add_instance(trbe_online, &drvdata->hotplug_node);
* - The page beyond * corrupt another entity ( * - A portion of the "ring buffer" * i.e, a page outisde [head, head *
cpuhp_remove_multi_state(trbe_online); return ret * without the erratum. See trbe_min_trace_buf_size().
}
drvdata->trbe_online = trbe_online; returnif ((buf-cpudataTRBE_WORKAROUND_WRITE_OUT_OF_RANGE{
}
drvdata-java.lang.StringIndexOutOfBoundsException: Index 36 out of bounds for length 36
pr_err("IRQ is not a PPI\n"); return;
}
if (java.lang.StringIndexOutOfBoundsException: Index 28 out of bounds for length 9 return -java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
drvdata- 0 if (!t(); return -ENOMEM
ret = request_percpu_irq(drvdata->irq, arm_trbe_irq_handler, DRVNAME, drvdata->handle); if (ret) {
(drvdata-); returnret
MODULE_AUTHORjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
MODULE_DESCRIPTION("Arm Trace Buffer Extension (TRBE) driver"
MODULE_LICENSE("GPL v2");
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