]> git.baikalelectronics.ru Git - kernel.git/commit
MIPS: VDSO: Add implementation of clock_gettime() fallback
authorGoran Ferenc <goran.ferenc@imgtec.com>
Wed, 28 Jun 2017 15:55:29 +0000 (17:55 +0200)
committerRalf Baechle <ralf@linux-mips.org>
Thu, 29 Jun 2017 00:42:29 +0000 (02:42 +0200)
commitce8634e1c24e5488fdc113a88ff44fd30315cf6d
tree2230db590022baf0071409ed226b2934ec78fb5f
parent6fcbe911cbe611f0e2f5222dd2bc8991682e92f8
MIPS: VDSO: Add implementation of clock_gettime() fallback

This patch adds clock_gettime_fallback() function that wraps assembly
invocation of clock_gettime() syscall using __NR_clock_gettime.

This function is used if pure VDSO implementation of clock_gettime()
does not succeed for any reason. For example, it is called if the
clkid parameter of clock_gettime() is not one of the clkids listed
in the switch-case block of the function __vdso_clock_gettime()
(one such case for clkid is CLOCK_BOOTIME).

If syscall invocation via __NR_clock_gettime fails, register a3 will
be set. So, after the syscall, register a3 is tested and the return
value is negated if it's set.

Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16639/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/vdso/gettimeofday.c