dtrace: Avoid excessive pcpu allocations

We were previously allocating MAXCPU structures for several purposes,
but this is generally unnecessary and is quite excessive, especially
after MAXCPU was b

dtrace: Avoid excessive pcpu allocations

We were previously allocating MAXCPU structures for several purposes,
but this is generally unnecessary and is quite excessive, especially
after MAXCPU was bumped to 1024 on amd64 and arm64. We already are
careful to allocate only as many per-CPU tracing buffers as are needed;
extend this to other allocations.

For example, in a 2-vCPU VM, the size of a consumer state structure
drops from 64KB to 128B. The size of the per-consumer `dts_buffer` and
`dts_aggbuffer` arrays shrink similarly. Ditto for pre-allocations of
local and global D variable storage space.

MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D47667

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sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

dtrace: Avoid excessive pcpu allocations

We were previously allocating MAXCPU structures for several purposes,
but this is generally unnecessary and is quite excessive, especially
after MAXCPU was b

dtrace: Avoid excessive pcpu allocations

We were previously allocating MAXCPU structures for several purposes,
but this is generally unnecessary and is quite excessive, especially
after MAXCPU was bumped to 1024 on amd64 and arm64. We already are
careful to allocate only as many per-CPU tracing buffers as are needed;
extend this to other allocations.

For example, in a 2-vCPU VM, the size of a consumer state structure
drops from 64KB to 128B. The size of the per-consumer `dts_buffer` and
`dts_aggbuffer` arrays shrink similarly. Ditto for pre-allocations of
local and global D variable storage space.

MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D47667

show more ...

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Don't use pcpu_find() to determine if a CPU ID is valid.

This addresses assertion failures after r326218.

MFC after: 1 week

Merge ^/head r313055 through r313300.

MFhead@r313266

Use PC-relative relocations for USDT probe sites on i386 and amd64.

When recording probe site addresses in the output DOF file, dtrace -G
needs to emit relocations for the .SUNW_dof section in order

Use PC-relative relocations for USDT probe sites on i386 and amd64.

When recording probe site addresses in the output DOF file, dtrace -G
needs to emit relocations for the .SUNW_dof section in order to obtain
the addresses of functions containing probe sites. DTrace expects the
addresses to be relative to the base address of the final ELF file,
and the amd64 USDT implementation was relying on some unspecified and
incorrect behaviour in the base system GNU ld to achieve this.

This change reimplements the probe site relocation handling to allow
USDT to be used with lld and newer GNU binutils. Specifically, it
makes use of R_X86_64_PC64/R_386_PC32 relocations to obtain the
probe site address relative to the DOF file address, and adds and uses a
new DOF relocation type which computes the final probe site address using
these relative offsets.

Reported by and discussed with: Rafael Espíndola
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D9374

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MFhead@r313243

Merge ^/head r312720 through r312893.

Fix initialization of "p" after r312658.

CID: 1369410

Merge ^/head r312624 through r312719.

Remove the DTRACEHIOC_ADD ioctl.

This ioctl has been considered legacy by upstream since the DTrace code
was first imported, and is unused. The removal also allows some
simplification of dtrace_help

Remove the DTRACEHIOC_ADD ioctl.

This ioctl has been considered legacy by upstream since the DTrace code
was first imported, and is unused. The removal also allows some
simplification of dtrace_helper_slurp().

Also remove a bogus copyout in the DTRACEHIOC_ADDDOF handler. Due to a
bug, it would overwrite an in-memory copy of the DOF header rather than
the passed-in DOF helper. Moreover, DTRACEHIOC_ADDDOF already copies the
helper back out automatically since its argument has the IOC_OUT attribute.

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MFH

Sponsored by: The FreeBSD Foundation

Fix a couple of silly mistakes in r291962.

- Handle the case where no DOF helper is provided. This occurs with the
currently-unused DTRACEHIOC_ADD ioctl.
- Fix some checks that prevented the loadi

Fix a couple of silly mistakes in r291962.

- Handle the case where no DOF helper is provided. This occurs with the
currently-unused DTRACEHIOC_ADD ioctl.
- Fix some checks that prevented the loading DOF in the (non-default)
lazyload mode.

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MFH r289384-r293170

Sponsored by: The FreeBSD Foundation

MFH @r292599

This includes the pluggable TCP framework and other chnages to the
netstack to track for VNET stability.

Security: The FreeBSD Foundation

Modify DTRACEHIOC_ADDDOF to copy the DOF section from the target process.

r281257 added support for lazyload mode by allowing dtrace(1) to register
a DOF section on behalf of a traced process. This

Modify DTRACEHIOC_ADDDOF to copy the DOF section from the target process.

r281257 added support for lazyload mode by allowing dtrace(1) to register
a DOF section on behalf of a traced process. This was implemented by
having libdtrace copy the DOF section into a heap-allocated buffer and
passing its address to the ioctl handler. However, DTrace uses the DOF
section address as a lookup key in certain cases, so the ioctl handler
should be given the target process' DOF section address instead. This
change modifies the ADDDOF handler to copy the DOF section in from the
target process, rather than from dtrace(1).

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Catch up with HEAD (r280229-r284686).

Merge sync of head

Merge from head

MFH: r280643-r281852

Sponsored by: The FreeBSD Foundation

libdtrace: add support for lazyload mode.

Passing "-x lazyload" to dtrace -G during compilation causes dtrace(1) to
not link drti.o into the output object file, so the USDT probes are not created
du

libdtrace: add support for lazyload mode.

Passing "-x lazyload" to dtrace -G during compilation causes dtrace(1) to
not link drti.o into the output object file, so the USDT probes are not created
during process startup. Instead, dtrace(1) will automatically discover and
create probes on the process' behalf when attaching.

Differential Revision: https://reviews.freebsd.org/D2203
Reviewed by: rpaulo
MFC after: 1 month

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MFhead @ r277403

Reintegrate head: r274132-r277384

Sponsored by: The FreeBSD Foundation