| Message ID | 20240520123020.18938-14-ilpo.jarvinen@linux.intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | selftests/resctrl: resctrl_val() related cleanups & improvements | expand |
Hi Ilpo, On 5/20/24 5:30 AM, Ilpo Järvinen wrote: > The struct resctrl_val_param has control and monitor groups as char > arrays but they are not supposed to be mutated within resctrl_val(). > > Convert the ctrlgrp and mongrp char array within resctrl_val_param to > plain const char pointers and adjust the strlen() based checks to > check NULL instead. > > Convert !grp_name check in create_grp() into internal sanity check by > returning error if the caller asked to create a group but doesn't > provide a name for the group. The existing code already abides this by > only calling create_grp() if mongrp is non-NULL so the error should > never be returned with the current selftests (ctrlgrp is never NULL). > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> > --- > > v3: > - Removed wrong comment > - Changed grp_name check to return -1 on fail (internal sanity check) > --- > tools/testing/selftests/resctrl/resctrl.h | 4 ++-- > tools/testing/selftests/resctrl/resctrlfs.c | 15 +++++---------- > 2 files changed, 7 insertions(+), 12 deletions(-) > > diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h > index 5967389038d4..a999fbc13fd3 100644 > --- a/tools/testing/selftests/resctrl/resctrl.h > +++ b/tools/testing/selftests/resctrl/resctrl.h > @@ -91,8 +91,8 @@ struct resctrl_test { > */ > struct resctrl_val_param { > char *resctrl_val; > - char ctrlgrp[64]; > - char mongrp[64]; > + const char *ctrlgrp; > + const char *mongrp; > char filename[64]; > unsigned long mask; > int num_of_runs; > diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c > index a0e84157eb63..6b4448588666 100644 > --- a/tools/testing/selftests/resctrl/resctrlfs.c > +++ b/tools/testing/selftests/resctrl/resctrlfs.c > @@ -464,13 +464,8 @@ static int create_grp(const char *grp_name, char *grp, const char *parent_grp) > struct dirent *ep; > DIR *dp; > > - /* > - * At this point, we are guaranteed to have resctrl FS mounted and if > - * length of grp_name == 0, it means, user wants to use root con_mon > - * grp, so do nothing > - */ > - if (strlen(grp_name) == 0) > - return 0; > + if (!grp_name) > + return -1; As I said during review of v2, this should not be an error. I went back to read your comments and the argument that this is done for benefit of API is unclear since the default control group does not have a name, exactly what create_grp() supports when not returning an error in this case. Reinette
On Wed, 29 May 2024, Reinette Chatre wrote: > Hi Ilpo, > > On 5/20/24 5:30 AM, Ilpo Järvinen wrote: > > The struct resctrl_val_param has control and monitor groups as char > > arrays but they are not supposed to be mutated within resctrl_val(). > > > > Convert the ctrlgrp and mongrp char array within resctrl_val_param to > > plain const char pointers and adjust the strlen() based checks to > > check NULL instead. > > > > Convert !grp_name check in create_grp() into internal sanity check by > > returning error if the caller asked to create a group but doesn't > > provide a name for the group. The existing code already abides this by > > only calling create_grp() if mongrp is non-NULL so the error should > > never be returned with the current selftests (ctrlgrp is never NULL). > > > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> > > --- > > > > v3: > > - Removed wrong comment > > - Changed grp_name check to return -1 on fail (internal sanity check) > > --- > > tools/testing/selftests/resctrl/resctrl.h | 4 ++-- > > tools/testing/selftests/resctrl/resctrlfs.c | 15 +++++---------- > > 2 files changed, 7 insertions(+), 12 deletions(-) > > > > diff --git a/tools/testing/selftests/resctrl/resctrl.h > > b/tools/testing/selftests/resctrl/resctrl.h > > index 5967389038d4..a999fbc13fd3 100644 > > --- a/tools/testing/selftests/resctrl/resctrl.h > > +++ b/tools/testing/selftests/resctrl/resctrl.h > > @@ -91,8 +91,8 @@ struct resctrl_test { > > */ > > struct resctrl_val_param { > > char *resctrl_val; > > - char ctrlgrp[64]; > > - char mongrp[64]; > > + const char *ctrlgrp; > > + const char *mongrp; > > char filename[64]; > > unsigned long mask; > > int num_of_runs; > > diff --git a/tools/testing/selftests/resctrl/resctrlfs.c > > b/tools/testing/selftests/resctrl/resctrlfs.c > > index a0e84157eb63..6b4448588666 100644 > > --- a/tools/testing/selftests/resctrl/resctrlfs.c > > +++ b/tools/testing/selftests/resctrl/resctrlfs.c > > @@ -464,13 +464,8 @@ static int create_grp(const char *grp_name, char *grp, > > const char *parent_grp) > > struct dirent *ep; > > DIR *dp; > > - /* > > - * At this point, we are guaranteed to have resctrl FS mounted and if > > - * length of grp_name == 0, it means, user wants to use root con_mon > > - * grp, so do nothing > > - */ > > - if (strlen(grp_name) == 0) > > - return 0; > > + if (!grp_name) > > + return -1; > > As I said during review of v2, this should not be an error. I went back to > read > your comments and the argument that this is done for benefit of API is unclear > since > the default control group does not have a name, exactly what create_grp() > supports > when not returning an error in this case. Okay, I did not know about this expectation related to the default control group because it's not used anywhere in the selftest code that always provides a ctrlgrp name. I'll change it to return 0.
diff --git a/tools/testing/selftests/resctrl/resctrl.h b/tools/testing/selftests/resctrl/resctrl.h index 5967389038d4..a999fbc13fd3 100644 --- a/tools/testing/selftests/resctrl/resctrl.h +++ b/tools/testing/selftests/resctrl/resctrl.h @@ -91,8 +91,8 @@ struct resctrl_test { */ struct resctrl_val_param { char *resctrl_val; - char ctrlgrp[64]; - char mongrp[64]; + const char *ctrlgrp; + const char *mongrp; char filename[64]; unsigned long mask; int num_of_runs; diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index a0e84157eb63..6b4448588666 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -464,13 +464,8 @@ static int create_grp(const char *grp_name, char *grp, const char *parent_grp) struct dirent *ep; DIR *dp; - /* - * At this point, we are guaranteed to have resctrl FS mounted and if - * length of grp_name == 0, it means, user wants to use root con_mon - * grp, so do nothing - */ - if (strlen(grp_name) == 0) - return 0; + if (!grp_name) + return -1; /* Check if requested grp exists or not */ dp = opendir(parent_grp); @@ -541,7 +536,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, char tasks[1024]; int ret = 0; - if (strlen(ctrlgrp)) + if (ctrlgrp) sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp); else sprintf(controlgroup, "%s", RESCTRL_PATH); @@ -558,7 +553,7 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, /* Create mon grp and write pid into it for "mbm" and "cmt" test */ if (!strncmp(resctrl_val, CMT_STR, sizeof(CMT_STR)) || !strncmp(resctrl_val, MBM_STR, sizeof(MBM_STR))) { - if (strlen(mongrp)) { + if (mongrp) { sprintf(monitorgroup_p, "%s/mon_groups", controlgroup); sprintf(monitorgroup, "%s/%s", monitorgroup_p, mongrp); ret = create_grp(mongrp, monitorgroup, monitorgroup_p); @@ -612,7 +607,7 @@ int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no, goto out; } - if (strlen(ctrlgrp) != 0) + if (ctrlgrp) sprintf(controlgroup, "%s/%s/schemata", RESCTRL_PATH, ctrlgrp); else sprintf(controlgroup, "%s/schemata", RESCTRL_PATH);
The struct resctrl_val_param has control and monitor groups as char arrays but they are not supposed to be mutated within resctrl_val(). Convert the ctrlgrp and mongrp char array within resctrl_val_param to plain const char pointers and adjust the strlen() based checks to check NULL instead. Convert !grp_name check in create_grp() into internal sanity check by returning error if the caller asked to create a group but doesn't provide a name for the group. The existing code already abides this by only calling create_grp() if mongrp is non-NULL so the error should never be returned with the current selftests (ctrlgrp is never NULL). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> --- v3: - Removed wrong comment - Changed grp_name check to return -1 on fail (internal sanity check) --- tools/testing/selftests/resctrl/resctrl.h | 4 ++-- tools/testing/selftests/resctrl/resctrlfs.c | 15 +++++---------- 2 files changed, 7 insertions(+), 12 deletions(-)