Currently when RLC queues (user mode queues) are mapped, the read/write
pointers of the ring buffer are set to zero. However, these queues could
be unmapped and then remapped later. In that situation the read/write
pointers should be the previous value before unmapping occurred. Since
the read pointer gets reset to zero, the queue begins reading from the
start of the ring, which usually contains older packets. There is a 99%
chance those packets contain addresses which are no longer in the page
tables which will cause a page fault.
To fix this we update the MQD with the current read/write pointer values
and then writeback the MQD to memory when the queue is unmapped. This
requires adding a pointer to the MQD and the host address of the MQD
where it should be written back to. The interface for registering RLC
queue is also simplified. Since we need to pass the MQD anyway, we can
get values from it as well.
Fixes b+tree and streamcluster from rodinia (when using RLC queues).
Change-Id: Ie5dad4d7d90ea240c3e9f0cddf3e844a3cd34c4f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65791
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Currently the SDMA queue type is guessed in the trap method by looking
at which queue in the engine is processing packets. It is possible for
both queues to be processing (e.g., one queue sent a DMA and is waiting
then switch to another queue), triggering an assert.
Instead store the queue type in the queue itself and use that type in
trap to determine which ring ID to use for the interrupt packet.
Change-Id: If91c458e60a03f2013c0dc42bab0b1673e3dbd84
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65691
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The current SDMA wrap around handling only considers the ring buffer
location as seen by the GPU. Eventually when the end of the SDMA ring
buffer is reached, the driver waits until the rptr written back to the
host catches up to what the driver sees before wrapping around back to
the beginning of the buffer. This writeback currently does not happen at
all, causing hangs for applications with a lot of SDMA commands.
This changeset first fixes the sizes of the queues, especially RLC
queues, so that the wrap around occurs in the correct place. Second, we
now store the rptr writeback address and the absoluate (unwrapped) rptr
value in each SDMA queue. The absolulte rptr is what the driver sends to
the device and what it expects to be written back.
This was tested with an application which basically does a few hundred
thousand hipMemcpy() calls in a loop. It should also fix the issue with
pannotia BC in fullsystem mode.
Change-Id: I53ebdcc6b02fb4eb4da435c9a509544066a97069
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65351
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
This debug flag is used to print spammy SDMA DPRINTFs, such as an SDMA
copy printing the data of large transfers 8 bytes per line at a time. For
those prints, the SDMAEngine flag will now only print the first and last
qword of the transfer and the new SDMAData flag is needed for verbose
data printing. This makes the SDMAEngine flag still useful for verifying
copies in applications with predictable data such as square.
Additionally, the memory allocation/deallocation done solely for a print
statement is removed in favor of casting the data to the printed type.
Change-Id: I18c1918ef9085cca4570f79881ee63d510ccc32f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64452
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
SDMA atomic packets are used in conjunction with RLC queues in SDMA for
synchronization similar to how HSA signals are used with BLIT kernels
when SDMA is disabled. Implement a skeleton of the SDMA atomic packet
methods as well as the atomic add64 operation.
The atomic add operation appears to be the only operation used in ROCm,
so this implementation is fairly complete. See:
https://github.com/RadeonOpenCompute/ROCR-Runtime/blob/
rocm-4.2.x/src/core/runtime/amd_blit_sdma.cpp#L880
Change-Id: I62cc337f2ffe590bdb947b48053760ee8b3a6f32
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63174
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
There can only ever be two RLC queues maximum. Use this information for
a simpler data structure to store doorbell information. The patch
changes the std::unordered_map previously used to std::array. This will
also be useful in avoiding erase-while-iterating issues needed to
unregister all queues at once.
Change-Id: I95600e40de51cb1a992a20bcebaf7580ea4d0be8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/63172
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
SDMAEngine handles copies to device memory. This commit
updates sdma_packets.hh style as well. Added several methods needed by
SDMAEngine to GPU device including GART table, various getters, and
aperture range checkers. Move the MMIO interface from GPUController to
SDMAEngine. Create an SDMA MMIO and commands header with only the macros
we use so that we don't need to check in multi-thousand line header
files from the linux kernel. Keep SOC15 IH client ID macros as that file
is small.
Change-Id: I986fede90cc1bc16ee56d4e8598cf9283bde034e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53064
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
