From mboxrd@z Thu Jan 1 00:00:00 1970 From: David.Laight@ACULAB.COM (David Laight) Date: Tue, 27 Nov 2018 15:48:52 +0000 Subject: [PATCH] arm: always update thread_info->syscall In-Reply-To: <20181127153553.GE30658@n2100.armlinux.org.uk> References: <20181126225335.10477-1-rafael.tinoco@linaro.org> <20181126233303.GZ30658@n2100.armlinux.org.uk> <20181126234111.GA30658@n2100.armlinux.org.uk> <20181126234456.GB30658@n2100.armlinux.org.uk> <20181127105620.GD30658@n2100.armlinux.org.uk> <20181127153553.GE30658@n2100.armlinux.org.uk> Message-ID: <23ea6d5cbaac4cc3ad60d6184bbd1997@AcuMS.aculab.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Russell King - ARM Linux > Sent: 27 November 2018 15:36 ... > There appears to be no documentation at all of this interface, so there > is no definition of how it is supposed to work or what it is supposed > to expose beyond what little information is in the original patch: > > http://lkml.iu.edu/hypermail/linux/kernel/0807.2/0577.html > > This adds /proc/PID/syscall and /proc/PID/task/TID/syscall magic files. > These use task_current_syscall() to show the task's current system call > number and argument registers, stack pointer and PC. For a task blocked > but not in a syscall, the file shows "-1" in place of the syscall number, > followed by only the SP and PC. For a task that's not blocked, it shows > "running". I 'like' the way the columns for sp and pc jump about ... David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)