From fe4d0d5dde457bb5832b866418b5036f4f0c8d13 Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Fri, 29 Apr 2022 16:54:58 +0200 Subject: [PATCH 1/6] rtla/Makefile: Properly handle dependencies Linus had a problem compiling RTLA, saying: "[...] I wish the tracing tools would do a bit more package checking and helpful error messages too, rather than just fail with: fatal error: tracefs.h: No such file or directory" Which is indeed not a helpful message. Update the Makefile, adding proper checks for the dependencies, with useful information about how to resolve possible problems. For example, the previous error is now reported as: $ make ******************************************** ** NOTICE: libtracefs version 1.3 or higher not found ** ** Consider installing the latest libtracefs from your ** distribution, e.g., 'dnf install libtracefs' on Fedora, ** or from source: ** ** https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/ ** ******************************************** These messages are inspired by the ones used on trace-cmd, as suggested by Stevel Rostedt. Link: https://lore.kernel.org/r/CAHk-=whxmA86E=csNv76DuxX_wYsg8mW15oUs3XTabu2Yc80yw@mail.gmail.com/ Changes from V1: - Moved the rst2man check to the install phase (when it is used). - Removed the procps-ng lib check [1] as it is being removed. [1] a0f9f8c1030c66305c9b921057c3d483064d5529.1651220820.git.bristot@kernel.org Link: https://lkml.kernel.org/r/3f1fac776c37e4b67c876a94e5a0e45ed022ff3d.1651238057.git.bristot@kernel.org Cc: Ingo Molnar Cc: Andrew Morton Reported-by: Linus Torvalds Suggested-by: Steven Rostedt Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- Documentation/tools/rtla/Makefile | 14 ++++++++++++- tools/tracing/rtla/Makefile | 35 +++++++++++++++++++++++++++++++ 2 files changed, 48 insertions(+), 1 deletion(-) diff --git a/Documentation/tools/rtla/Makefile b/Documentation/tools/rtla/Makefile index 9f2b84af1a6c..093af6d7a0e9 100644 --- a/Documentation/tools/rtla/Makefile +++ b/Documentation/tools/rtla/Makefile @@ -17,9 +17,21 @@ DOC_MAN1 = $(addprefix $(OUTPUT),$(_DOC_MAN1)) RST2MAN_DEP := $(shell command -v rst2man 2>/dev/null) RST2MAN_OPTS += --verbose +TEST_RST2MAN = $(shell sh -c "rst2man --version > /dev/null 2>&1 || echo n") + $(OUTPUT)%.1: %.rst ifndef RST2MAN_DEP - $(error "rst2man not found, but required to generate man pages") + $(info ********************************************) + $(info ** NOTICE: rst2man not found) + $(info **) + $(info ** Consider installing the latest rst2man from your) + $(info ** distribution, e.g., 'dnf install python3-docutils' on Fedora,) + $(info ** or from source:) + $(info **) + $(info ** https://docutils.sourceforge.io/docs/dev/repository.html ) + $(info **) + $(info ********************************************) + $(error NOTICE: rst2man required to generate man pages) endif rst2man $(RST2MAN_OPTS) $< > $@ diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile index 11fb417abb42..86d1df3763ef 100644 --- a/tools/tracing/rtla/Makefile +++ b/tools/tracing/rtla/Makefile @@ -57,6 +57,41 @@ else DOCSRC = $(SRCTREE)/../../../Documentation/tools/rtla/ endif +LIBTRACEEVENT_MIN_VERSION = 1.5 +LIBTRACEFS_MIN_VERSION = 1.3 + +TEST_LIBTRACEEVENT = $(shell sh -c "$(PKG_CONFIG) --atleast-version $(LIBTRACEEVENT_MIN_VERSION) libtraceevent > /dev/null 2>&1 || echo n") +ifeq ("$(TEST_LIBTRACEEVENT)", "n") +.PHONY: warning_traceevent +warning_traceevent: + @echo "********************************************" + @echo "** NOTICE: libtraceevent version $(LIBTRACEEVENT_MIN_VERSION) or higher not found" + @echo "**" + @echo "** Consider installing the latest libtraceevent from your" + @echo "** distribution, e.g., 'dnf install libtraceevent' on Fedora," + @echo "** or from source:" + @echo "**" + @echo "** https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/ " + @echo "**" + @echo "********************************************" +endif + +TEST_LIBTRACEFS = $(shell sh -c "$(PKG_CONFIG) --atleast-version $(LIBTRACEFS_MIN_VERSION) libtracefs > /dev/null 2>&1 || echo n") +ifeq ("$(TEST_LIBTRACEFS)", "n") +.PHONY: warning_tracefs +warning_tracefs: + @echo "********************************************" + @echo "** NOTICE: libtracefs version $(LIBTRACEFS_MIN_VERSION) or higher not found" + @echo "**" + @echo "** Consider installing the latest libtracefs from your" + @echo "** distribution, e.g., 'dnf install libtracefs' on Fedora," + @echo "** or from source:" + @echo "**" + @echo "** https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/ " + @echo "**" + @echo "********************************************" +endif + .PHONY: all all: rtla From 2a6b52ed72c822b5ee146a6a00ea66614fe02653 Mon Sep 17 00:00:00 2001 From: Wan Jiabing Date: Fri, 29 Apr 2022 18:28:10 +0200 Subject: [PATCH 2/6] rtla: Avoid record NULL pointer dereference Fix the following null/deref_null.cocci errors: ./tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/osnoise_top.c:650:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/timerlat_hist.c:905:31-36: ERROR: record is NULL but dereferenced. ./tools/tracing/rtla/src/timerlat_top.c:700:31-36: ERROR: record is NULL but dereferenced. "record" is NULL before calling osnoise_init_trace_tool. Add a tag "out_free" to avoid dereferring a NULL pointer. Link: https://lkml.kernel.org/r/ae0e4500d383db0884eb2820286afe34ca303778.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/20220408151406.34823-1-wanjiabing@vivo.com/ Cc: kael_w@yeah.net Cc: Daniel Bristot de Oliveira Fixes: 51d64c3a1819 ("rtla: Add -e/--event support") Acked-by: Daniel Bristot de Oliveira Signed-off-by: Wan Jiabing Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- tools/tracing/rtla/src/osnoise_hist.c | 5 +++-- tools/tracing/rtla/src/osnoise_top.c | 9 +++++---- tools/tracing/rtla/src/timerlat_hist.c | 11 ++++++----- tools/tracing/rtla/src/timerlat_top.c | 11 ++++++----- 4 files changed, 20 insertions(+), 16 deletions(-) diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c index b4380d45cacd..5d7ea479ac89 100644 --- a/tools/tracing/rtla/src/osnoise_hist.c +++ b/tools/tracing/rtla/src/osnoise_hist.c @@ -809,7 +809,7 @@ int osnoise_hist_main(int argc, char *argv[]) retval = set_comm_sched_attr("osnoise/", ¶ms->sched_param); if (retval) { err_msg("Failed to set sched parameters\n"); - goto out_hist; + goto out_free; } } @@ -819,7 +819,7 @@ int osnoise_hist_main(int argc, char *argv[]) record = osnoise_init_trace_tool("osnoise"); if (!record) { err_msg("Failed to enable the trace instance\n"); - goto out_hist; + goto out_free; } if (params->events) { @@ -869,6 +869,7 @@ int osnoise_hist_main(int argc, char *argv[]) out_hist: trace_events_destroy(&record->trace, params->events); params->events = NULL; +out_free: osnoise_free_histogram(tool->data); out_destroy: osnoise_destroy_tool(record); diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c index 72c2fd6ce005..76479bfb2922 100644 --- a/tools/tracing/rtla/src/osnoise_top.c +++ b/tools/tracing/rtla/src/osnoise_top.c @@ -572,7 +572,7 @@ int osnoise_top_main(int argc, char **argv) retval = osnoise_top_apply_config(tool, params); if (retval) { err_msg("Could not apply config\n"); - goto out_top; + goto out_free; } trace = &tool->trace; @@ -580,14 +580,14 @@ int osnoise_top_main(int argc, char **argv) retval = enable_osnoise(trace); if (retval) { err_msg("Failed to enable osnoise tracer\n"); - goto out_top; + goto out_free; } if (params->set_sched) { retval = set_comm_sched_attr("osnoise/", ¶ms->sched_param); if (retval) { err_msg("Failed to set sched parameters\n"); - goto out_top; + goto out_free; } } @@ -597,7 +597,7 @@ int osnoise_top_main(int argc, char **argv) record = osnoise_init_trace_tool("osnoise"); if (!record) { err_msg("Failed to enable the trace instance\n"); - goto out_top; + goto out_free; } if (params->events) { @@ -649,6 +649,7 @@ int osnoise_top_main(int argc, char **argv) out_top: trace_events_destroy(&record->trace, params->events); params->events = NULL; +out_free: osnoise_free_top(tool->data); osnoise_destroy_tool(record); osnoise_destroy_tool(tool); diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c index dc908126c610..f3ec628f5e51 100644 --- a/tools/tracing/rtla/src/timerlat_hist.c +++ b/tools/tracing/rtla/src/timerlat_hist.c @@ -821,7 +821,7 @@ int timerlat_hist_main(int argc, char *argv[]) retval = timerlat_hist_apply_config(tool, params); if (retval) { err_msg("Could not apply config\n"); - goto out_hist; + goto out_free; } trace = &tool->trace; @@ -829,14 +829,14 @@ int timerlat_hist_main(int argc, char *argv[]) retval = enable_timerlat(trace); if (retval) { err_msg("Failed to enable timerlat tracer\n"); - goto out_hist; + goto out_free; } if (params->set_sched) { retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param); if (retval) { err_msg("Failed to set sched parameters\n"); - goto out_hist; + goto out_free; } } @@ -844,7 +844,7 @@ int timerlat_hist_main(int argc, char *argv[]) dma_latency_fd = set_cpu_dma_latency(params->dma_latency); if (dma_latency_fd < 0) { err_msg("Could not set /dev/cpu_dma_latency.\n"); - goto out_hist; + goto out_free; } } @@ -854,7 +854,7 @@ int timerlat_hist_main(int argc, char *argv[]) record = osnoise_init_trace_tool("timerlat"); if (!record) { err_msg("Failed to enable the trace instance\n"); - goto out_hist; + goto out_free; } if (params->events) { @@ -904,6 +904,7 @@ out_hist: close(dma_latency_fd); trace_events_destroy(&record->trace, params->events); params->events = NULL; +out_free: timerlat_free_histogram(tool->data); osnoise_destroy_tool(record); osnoise_destroy_tool(tool); diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c index 1f754c3df53f..35452a1d45e9 100644 --- a/tools/tracing/rtla/src/timerlat_top.c +++ b/tools/tracing/rtla/src/timerlat_top.c @@ -612,7 +612,7 @@ int timerlat_top_main(int argc, char *argv[]) retval = timerlat_top_apply_config(top, params); if (retval) { err_msg("Could not apply config\n"); - goto out_top; + goto out_free; } trace = &top->trace; @@ -620,14 +620,14 @@ int timerlat_top_main(int argc, char *argv[]) retval = enable_timerlat(trace); if (retval) { err_msg("Failed to enable timerlat tracer\n"); - goto out_top; + goto out_free; } if (params->set_sched) { retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param); if (retval) { err_msg("Failed to set sched parameters\n"); - goto out_top; + goto out_free; } } @@ -635,7 +635,7 @@ int timerlat_top_main(int argc, char *argv[]) dma_latency_fd = set_cpu_dma_latency(params->dma_latency); if (dma_latency_fd < 0) { err_msg("Could not set /dev/cpu_dma_latency.\n"); - goto out_top; + goto out_free; } } @@ -645,7 +645,7 @@ int timerlat_top_main(int argc, char *argv[]) record = osnoise_init_trace_tool("timerlat"); if (!record) { err_msg("Failed to enable the trace instance\n"); - goto out_top; + goto out_free; } if (params->events) { @@ -699,6 +699,7 @@ out_top: close(dma_latency_fd); trace_events_destroy(&record->trace, params->events); params->events = NULL; +out_free: timerlat_free_top(top->data); osnoise_destroy_tool(record); osnoise_destroy_tool(top); From 39c3d84cb5b52792a7323a338334d8d65b2dbe3f Mon Sep 17 00:00:00 2001 From: John Kacur Date: Fri, 29 Apr 2022 18:28:11 +0200 Subject: [PATCH 3/6] rtla: Don't overwrite existing directory mode The mode on /usr/bin is often 555 these days, but make install on rtla overwrites this with 755 Fix this by preserving the current directory if it exists. Link: https://lkml.kernel.org/r/8c294a6961080a1970fd8b73f7bcf1e3984579e2.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/20220402043939.6962-1-jkacur@redhat.com Cc: Daniel Bristot de Oliveria Fixes: 79ce8f43ac5a ("rtla: Real-Time Linux Analysis tool") Acked-by: Daniel Bristot de Oliveira Signed-off-by: John Kacur Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- tools/tracing/rtla/Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile index 86d1df3763ef..e28ae3f78264 100644 --- a/tools/tracing/rtla/Makefile +++ b/tools/tracing/rtla/Makefile @@ -23,6 +23,7 @@ $(call allow-override,LD_SO_CONF_PATH,/etc/ld.so.conf.d/) $(call allow-override,LDCONFIG,ldconfig) INSTALL = install +MKDIR = mkdir FOPTS := -flto=auto -ffat-lto-objects -fexceptions -fstack-protector-strong \ -fasynchronous-unwind-tables -fstack-clash-protection WOPTS := -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -Wno-maybe-uninitialized @@ -103,7 +104,7 @@ static: $(OBJ) .PHONY: install install: doc_install - $(INSTALL) -d -m 755 $(DESTDIR)$(BINDIR) + $(MKDIR) -p $(DESTDIR)$(BINDIR) $(INSTALL) rtla -m 755 $(DESTDIR)$(BINDIR) $(STRIP) $(DESTDIR)$(BINDIR)/rtla @test ! -f $(DESTDIR)$(BINDIR)/osnoise || rm $(DESTDIR)$(BINDIR)/osnoise From 22d146f7c1e97f4870e4497c0202939a031f740c Mon Sep 17 00:00:00 2001 From: John Kacur Date: Fri, 29 Apr 2022 18:28:12 +0200 Subject: [PATCH 4/6] rtla: Minor grammar fix for rtla README - Change to "The rtla meta-tool includes" - Remove an unnecessary "But, " - Adjust the formatting of the paragraph resulting from the changes. - Simplify the wording for the libraries and tools. Link: https://lkml.kernel.org/r/437f0accdde53713ab3cce46f3564be00487e031.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/20220408161012.10544-1-jkacur@redhat.com/ Cc: Daniel Bristot de Oliveria Fixes: 79ce8f43ac5a ("rtla: Real-Time Linux Analysis tool") Acked-by: Daniel Bristot de Oliveira Signed-off-by: John Kacur Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- tools/tracing/rtla/README.txt | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/tools/tracing/rtla/README.txt b/tools/tracing/rtla/README.txt index 6c88446f7e74..0fbad2640b8c 100644 --- a/tools/tracing/rtla/README.txt +++ b/tools/tracing/rtla/README.txt @@ -1,15 +1,13 @@ RTLA: Real-Time Linux Analysis tools -The rtla is a meta-tool that includes a set of commands that -aims to analyze the real-time properties of Linux. But, instead of -testing Linux as a black box, rtla leverages kernel tracing -capabilities to provide precise information about the properties -and root causes of unexpected results. +The rtla meta-tool includes a set of commands that aims to analyze +the real-time properties of Linux. Instead of testing Linux as a black box, +rtla leverages kernel tracing capabilities to provide precise information +about the properties and root causes of unexpected results. Installing RTLA -RTLA depends on some libraries and tools. More precisely, it depends on the -following libraries: +RTLA depends on the following libraries and tools: - libtracefs - libtraceevent From 941a53c39a151e9aceef153cdfaed0f166ba01b7 Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Fri, 29 Apr 2022 18:28:13 +0200 Subject: [PATCH 5/6] rtla: Fix __set_sched_attr error message rtla's function __set_sched_attr() was borrowed from stalld, but I forgot to update the error message to something meaningful for rtla. Update the error message from: boost_with_deadline failed to boost pid PID: STRERROR to a proper one: Failed to set sched attributes to the pid PID: STRERROR Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/ Fixes: b1696371d865 ("rtla: Helper functions for rtla") Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- tools/tracing/rtla/src/utils.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index da2b590edaed..3bd6f64780cf 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -255,7 +255,7 @@ int __set_sched_attr(int pid, struct sched_attr *attr) retval = sched_setattr(pid, attr, flags); if (retval < 0) { - err_msg("boost_with_deadline failed to boost pid %d: %s\n", + err_msg("Failed to set sched attributes to the pid %d: %s\n", pid, strerror(errno)); return 1; } From dada03db9bb1984826e61cfcf1418ac73848324d Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Fri, 13 May 2022 08:45:53 +0200 Subject: [PATCH 6/6] rtla: Remove procps-ng dependency Daniel Wagner reported to me that readproc.h got deprecated. Also, while the procps-ng library was available on Fedora, it was not available on RHEL, which is a piece of evidence that it was not that used. rtla uses procps-ng only to find the PID of the tracers' workload. I used the procps-ng library to avoid reinventing the wheel. But in this case, reinventing the wheel took me less time than the time we already took trying to work around problems. Implement a function that reads /proc/ entries, checking if: - the entry is a directory - the directory name is composed only of digits (PID) - the directory contains the comm file - the comm file contains a comm that matches the tracers' workload prefix. - then return true; otherwise, return false. And use it instead of procps-ng. Link: https://lkml.kernel.org/r/e8276e122ee9eb2c5a0ba8e673fb6488b924b825.1652423574.git.bristot@kernel.org Cc: John Kacur Cc: Steven Rostedt Cc: Tao Zhou Fixes: b1696371d865 ("rtla: Helper functions for rtla") Reported-by: Daniel Wagner Reviewed-by: Daniel Wagner Signed-off-by: Daniel Bristot de Oliveira Signed-off-by: Steven Rostedt (Google) --- tools/tracing/rtla/Makefile | 2 +- tools/tracing/rtla/README.txt | 1 - tools/tracing/rtla/src/utils.c | 108 ++++++++++++++++++++++++++------- tools/tracing/rtla/src/utils.h | 3 +- 4 files changed, 89 insertions(+), 25 deletions(-) diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile index e28ae3f78264..3822f4ea5f49 100644 --- a/tools/tracing/rtla/Makefile +++ b/tools/tracing/rtla/Makefile @@ -32,7 +32,7 @@ TRACEFS_HEADERS := $$($(PKG_CONFIG) --cflags libtracefs) CFLAGS := -O -g -DVERSION=\"$(VERSION)\" $(FOPTS) $(MOPTS) $(WOPTS) $(TRACEFS_HEADERS) LDFLAGS := -ggdb -LIBS := $$($(PKG_CONFIG) --libs libtracefs) -lprocps +LIBS := $$($(PKG_CONFIG) --libs libtracefs) SRC := $(wildcard src/*.c) HDR := $(wildcard src/*.h) diff --git a/tools/tracing/rtla/README.txt b/tools/tracing/rtla/README.txt index 0fbad2640b8c..4af3fd40f171 100644 --- a/tools/tracing/rtla/README.txt +++ b/tools/tracing/rtla/README.txt @@ -11,7 +11,6 @@ RTLA depends on the following libraries and tools: - libtracefs - libtraceevent - - procps It also depends on python3-docutils to compile man pages. diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index 3bd6f64780cf..5352167a1e75 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -3,7 +3,7 @@ * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira */ -#include +#include #include #include #include @@ -262,43 +262,107 @@ int __set_sched_attr(int pid, struct sched_attr *attr) return 0; } + /* - * set_comm_sched_attr - set sched params to threads starting with char *comm + * procfs_is_workload_pid - check if a procfs entry contains a comm_prefix* comm * - * This function uses procps to list the currently running threads and then - * set the sched_attr *attr to the threads that start with char *comm. It is + * Check if the procfs entry is a directory of a process, and then check if the + * process has a comm with the prefix set in char *comm_prefix. As the + * current users of this function only check for kernel threads, there is no + * need to check for the threads for the process. + * + * Return: True if the proc_entry contains a comm file with comm_prefix*. + * Otherwise returns false. + */ +static int procfs_is_workload_pid(const char *comm_prefix, struct dirent *proc_entry) +{ + char buffer[MAX_PATH]; + int comm_fd, retval; + char *t_name; + + if (proc_entry->d_type != DT_DIR) + return 0; + + if (*proc_entry->d_name == '.') + return 0; + + /* check if the string is a pid */ + for (t_name = proc_entry->d_name; t_name; t_name++) { + if (!isdigit(*t_name)) + break; + } + + if (*t_name != '\0') + return 0; + + snprintf(buffer, MAX_PATH, "/proc/%s/comm", proc_entry->d_name); + comm_fd = open(buffer, O_RDONLY); + if (comm_fd < 0) + return 0; + + memset(buffer, 0, MAX_PATH); + retval = read(comm_fd, buffer, MAX_PATH); + + close(comm_fd); + + if (retval <= 0) + return 0; + + retval = strncmp(comm_prefix, buffer, strlen(comm_prefix)); + if (retval) + return 0; + + /* comm already have \n */ + debug_msg("Found workload pid:%s comm:%s", proc_entry->d_name, buffer); + + return 1; +} + +/* + * set_comm_sched_attr - set sched params to threads starting with char *comm_prefix + * + * This function uses procfs to list the currently running threads and then set the + * sched_attr *attr to the threads that start with char *comm_prefix. It is * mainly used to set the priority to the kernel threads created by the * tracers. */ -int set_comm_sched_attr(const char *comm, struct sched_attr *attr) +int set_comm_sched_attr(const char *comm_prefix, struct sched_attr *attr) { - int flags = PROC_FILLCOM | PROC_FILLSTAT; - PROCTAB *ptp; - proc_t task; + struct dirent *proc_entry; + DIR *procfs; int retval; - ptp = openproc(flags); - if (!ptp) { - err_msg("error openproc()\n"); - return -ENOENT; + if (strlen(comm_prefix) >= MAX_PATH) { + err_msg("Command prefix is too long: %d < strlen(%s)\n", + MAX_PATH, comm_prefix); + return 1; } - memset(&task, 0, sizeof(task)); + procfs = opendir("/proc"); + if (!procfs) { + err_msg("Could not open procfs\n"); + return 1; + } - while (readproc(ptp, &task)) { - retval = strncmp(comm, task.cmd, strlen(comm)); - if (retval) + while ((proc_entry = readdir(procfs))) { + + retval = procfs_is_workload_pid(comm_prefix, proc_entry); + if (!retval) continue; - retval = __set_sched_attr(task.tid, attr); - if (retval) - goto out_err; - } - closeproc(ptp); + /* procfs_is_workload_pid confirmed it is a pid */ + retval = __set_sched_attr(atoi(proc_entry->d_name), attr); + if (retval) { + err_msg("Error setting sched attributes for pid:%s\n", proc_entry->d_name); + goto out_err; + } + + debug_msg("Set sched attributes for pid:%s\n", proc_entry->d_name); + } return 0; out_err: - closeproc(ptp); + closedir(procfs); return 1; } diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h index fa08e374870a..5571afd3b549 100644 --- a/tools/tracing/rtla/src/utils.h +++ b/tools/tracing/rtla/src/utils.h @@ -6,6 +6,7 @@ * '18446744073709551615\0' */ #define BUFF_U64_STR_SIZE 24 +#define MAX_PATH 1024 #define container_of(ptr, type, member)({ \ const typeof(((type *)0)->member) *__mptr = (ptr); \ @@ -53,5 +54,5 @@ struct sched_attr { }; int parse_prio(char *arg, struct sched_attr *sched_param); -int set_comm_sched_attr(const char *comm, struct sched_attr *attr); +int set_comm_sched_attr(const char *comm_prefix, struct sched_attr *attr); int set_cpu_dma_latency(int32_t latency);