aarch64: Fix nested counter macros #33145
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There are several issues with the current implemenation of the
{inc,dec}_nest_counter macros.
The first problem is that it's internally using a call to a misplaced
function called z_arm64_curr_cpu() (for some unknown reason hosted in
irq_manage.c) that could potentially clobber the caller-saved registers
without any notice to the user of the macro.
The second problem is that being a macro the clobbered registers should
be specified at the calling site, this is not possible given the current
implementation.
To fix these issues and make the call quicker, this patch rewrites the
code in assembly leveraging the availability of the _curr_cpu array. It
now clobbers only two registers passed from the calling site.
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
z_arm64_* prefix should not be used for macros. Rename it. Signed-off-by: Carlo Caione <ccaione@baylibre.com>
carlocaione
requested review from
MrVan,
ioannisg,
npitre,
sandeepbrcm and
stephanosio
npitre
approved these changes
Mar 8, 2021
jharris-intel
approved these changes
Mar 8, 2021
MrVan
approved these changes
Mar 9, 2021
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As explained in the commit message the
{inc,dec}_nested_countermacros have several problems, mainly the macros can unexpectedly clobber several registers without any notice. It's just better to make the clobbered registers explicit again and avoid using a call to function to retrieve the current cpu pointer.