Thomas Richter 1873f1547d perf probe: Add ustring support for perf probe command ... Kernel commit 88903c4643 ("tracing/probe: Add ustring type for user-space string") adds support for user-space strings when type 'ustring' is specified. Here is an example using sysfs command line interface for kprobes: Function to probe: struct filename * getname_flags(const char __user *filename, int flags, int *empty) Setup: # cd /sys/kernel/debug/tracing/ # echo 'p:tmr1 getname_flags +0(%r2):ustring' > kprobe_events # cat events/kprobes/tmr1/format | fgrep print print fmt: "(%lx) arg1=\"%s\"", REC->__probe_ip, REC->arg1 # echo 1 > events/kprobes/tmr1/enable # touch /tmp/111 # echo 0 > events/kprobes/tmr1/enable # cat trace|fgrep /tmp/111 touch-5846 [005] d..2 255520.717960: tmr1:\ (getname_flags+0x0/0x400) arg1="/tmp/111" Doing the same with the perf tool fails. Using type 'string' succeeds: # perf probe "vfs_getname=getname_flags:72 pathname=filename:string" Added new event: probe:vfs_getname (on getname_flags:72 with pathname=filename:string) .... # perf probe -d probe:vfs_getname Removed event: probe:vfs_getname However using type 'ustring' fails (output before): # perf probe "vfs_getname=getname_flags:72 pathname=filename:ustring" Failed to write event: Invalid argument Error: Failed to add events. # Fix this by adding type 'ustring' in function convert_variable_type(). Using ustring succeeds (output after): # ./perf probe "vfs_getname=getname_flags:72 pathname=filename:ustring" Added new event: probe:vfs_getname (on getname_flags:72 with pathname=filename:ustring) You can now use it in all perf tools, such as: perf record -e probe:vfs_getname -aR sleep 1 # Note: This issue also exists on x86, it is not s390 specific. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: sumanthk@linux.ibm.com Link: http://lore.kernel.org/lkml/20200120132011.64698-2-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>		2020-01-31 09:33:58 +01:00
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accounting
arch	tools arch x86: Sync asm/cpufeatures.h with the kernel sources	2019-12-02 15:20:05 -03:00
bpf	bpftool: Fix printing incorrect pointer in btf_dump_ptr	2020-01-11 19:08:21 -08:00
build	perf/ui/gtk: Fix gtk2 build	2020-01-14 12:40:33 -03:00
cgroup
debugging
firewire
firmware
gpio	tools: gpio: Correctly add make dependencies for gpio_utils	2019-11-13 13:46:04 +01:00
hv	tools: hv: add vmbus testing tool	2019-11-21 20:10:44 -05:00
iio	tools: iio: Correctly add make dependency for iio_utils	2019-11-10 17:11:06 +00:00
include	tools lib: Fix builds when glibc contains strlcpy()	2020-01-06 11:46:10 -03:00
io_uring
kvm/kvm_stat
laptop
leds
lib	perf/core improvements and fixes:	2020-01-20 08:44:04 +01:00
memory-model
nfsd
objtool	Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2019-11-26 15:04:47 -08:00
pci	tools: PCI: Fix fd leakage	2019-10-29 12:04:18 +00:00
pcmcia
perf	perf probe: Add ustring support for perf probe command	2020-01-31 09:33:58 +01:00
power	platform-drivers-x86 for v5.5-1	2019-12-01 18:24:25 -08:00
scripts
spi
testing	selftests: mlxsw: qos_mc_aware: Fix mausezahn invocation	2020-01-15 04:16:30 -08:00
thermal/tmon
time
usb	usbip: tools: fix fd leakage in the function of read_attr_usbip_status	2019-11-07 11:25:01 +01:00
virtio
vm
wmi
Makefile