Using the new PR_SET_VMA_ANON_NAME prctl attribute available since
the 5.17 release, when rolling out the process address map appears as
`
<start>-<end> r-xp 00000000 00:00 0 [anon:nodejs Large Page]
`
PR-URL: https://github.com/nodejs/node/pull/42644
Reviewed-By: James M Snell <jasnell@gmail.com>
* Introduce `OnScopeLeave` handler for cleaning up mmap()ed range(s).
* Factor out failure scenario at the bottom of the function with
`fail` label for use with `goto`.
* Do not allocate temporary range (`nmem`) on FreeBSD, because it is
not used.
The intention is that the steps involved in re-mapping to large pages
become more clearly visible.
Signed-off-by: Gabriel Schulhof <gabriel.schulhof@intel.com>
Co-authored-by: Ben Noordhuis <info@bnoordhuis.nl>
PR-URL: https://github.com/nodejs/node/pull/32396
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: David Carlier <devnexen@gmail.com>
We create an object file in assembly which introduces the symbol
`__node_text_start` into the .text section and place the resulting
object file as the first file the linker encounters. We do this to
ensure that we can recognize the boundaries of the .text section when
attempting to establish the address range to map to large pages.
Additionally, we rename the section containing the remapping code from
`.lpstub` to `lpstub` so as to take advantage of the linker's feature
whereby it inserts the symbol `__start_lpstub` when the section's name
can be rendered as a valid C variable. We need this symbol in order to
avoid self-mapping the remapping code to large pages, because doing so
would cause the process to crash.
PR-URL: https://github.com/nodejs/node/pull/31981
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Signed-off-by: Gabriel Schulhof <gabriel.schulhof@intel.com>
`__executable_start` is provided by GNU's and LLVM's default linker
scripts, obviating the need to plug in a custom linker script.
The problem with our bespoke linker script is that it works with ld.bfd
but not ld.gold and cannot easily be ported because the latter linker
doesn't understand the `INSERT BEFORE` directive.
The /proc/self/maps scanner is updated to account for the fact that
there are a number of sections between `&__executable_start` and
the start of the .text section.
Fortunately, those sections are all mapped into the same memory segment
so we only need to look at the next line to find the start of our text
segment.
Fixes: https://github.com/nodejs/node/issues/31520
PR-URL: https://github.com/nodejs/node/pull/31547
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Multiple sections may be marked as "r-xp" and with the executable's
path. We use the location of the `__nodetext` symbol added by the linker
script to ensure that the range we retrieve from the maps file does
indeed contain the Node.js text section.
Thanks to Suresh Srinivas <suresh.srinivas@intel.com>!
PR-URL: https://github.com/nodejs/node/pull/29973
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Proposal to bring the support for this platform.
We assume the pse36 cpu flag is present for 2MB
large page support present in recent years
in mac line (not to be backported to 10.x anyway).
Recommended better for mac production servers rather
than casual mac books.
PR-URL: https://github.com/nodejs/node/pull/28977
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
The custom linker script is compatible with GNU ld only.
As such, providin a new expliciting option to redirect to
a different one. lld seems unable to migrate this
large section w/o segfaulting so providing only the
base address anchor for now.
PR-URL: https://github.com/nodejs/node/pull/28938
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
This commit also adds error handling. A THP-enabled build terminated
with an out-of-memory error on a system without /proc because it cast
the -1 from readlink() to size_t (i.e. ULONG_MAX) and then tried to
allocate a string of that size.
PR-URL: https://github.com/nodejs/node/pull/28333
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
David CARLIER