| Message ID | 20210601030644.3318-5-chenbo.xia@intel.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | David Marchand |
| Headers | show |
| Series | Add mdev (Mediated device) support in DPDK | expand |
| Context | Check | Description |
|---|---|---|
| ci/checkpatch | success | coding style OK |
On Tue, 1 Jun 2021 11:06:42 +0800 Chenbo Xia <chenbo.xia@intel.com> wrote: > +int > +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) > +{ > + FILE *f; > + > + f = fopen(filename, "r"); > + if (f == NULL) { > + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", > + __func__, filename); > + return -1; > + } > + > + if (fgets(buf, sz, f) == NULL) { > + RTE_LOG(ERR, EAL, "%s(): cannot read sysfs file %s\n", > + __func__, filename); > + fclose(f); > + return -1; > + } > + > + fclose(f); > + return 0; > +} It would be helpful if function removed trailing newline. strchrnul(buf, '\n') = '\0';
On Tue, 1 Jun 2021 11:06:42 +0800 Chenbo Xia <chenbo.xia@intel.com> wrote: > > +int > +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) > +{ > + FILE *f; > + > + f = fopen(filename, "r"); > + if (f == NULL) { > + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", > + __func__, filename); Helpful to decode errno. RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s:%s\n", __func__, filename, strerror(errno));
Hi Stephen, > -----Original Message----- > From: Stephen Hemminger <stephen@networkplumber.org> > Sent: Tuesday, June 1, 2021 1:38 PM > To: Xia, Chenbo <chenbo.xia@intel.com> > Cc: dev@dpdk.org; thomas@monjalon.net; Liang, Cunming > <cunming.liang@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>; Burakov, > Anatoly <anatoly.burakov@intel.com>; Yigit, Ferruh <ferruh.yigit@intel.com>; > mdr@ashroe.eu; nhorman@tuxdriver.com; Richardson, Bruce > <bruce.richardson@intel.com>; david.marchand@redhat.com; Ananyev, Konstantin > <konstantin.ananyev@intel.com>; Tiwei Bie <tiwei.bie@intel.com> > Subject: Re: [RFC v3 4/6] eal: add a helper for reading string from sysfs > > On Tue, 1 Jun 2021 11:06:42 +0800 > Chenbo Xia <chenbo.xia@intel.com> wrote: > > > +int > > +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) > > +{ > > + FILE *f; > > + > > + f = fopen(filename, "r"); > > + if (f == NULL) { > > + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", > > + __func__, filename); > > + return -1; > > + } > > + > > + if (fgets(buf, sz, f) == NULL) { > > + RTE_LOG(ERR, EAL, "%s(): cannot read sysfs file %s\n", > > + __func__, filename); > > + fclose(f); > > + return -1; > > + } > > + > > + fclose(f); > > + return 0; > > +} > > It would be helpful if function removed trailing newline. > strchrnul(buf, '\n') = '\0'; Make sense. Will fix it. Thanks, Chenbo
Hi Stephen, > -----Original Message----- > From: Stephen Hemminger <stephen@networkplumber.org> > Sent: Tuesday, June 1, 2021 1:39 PM > To: Xia, Chenbo <chenbo.xia@intel.com> > Cc: dev@dpdk.org; thomas@monjalon.net; Liang, Cunming > <cunming.liang@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>; Burakov, > Anatoly <anatoly.burakov@intel.com>; Yigit, Ferruh <ferruh.yigit@intel.com>; > mdr@ashroe.eu; nhorman@tuxdriver.com; Richardson, Bruce > <bruce.richardson@intel.com>; david.marchand@redhat.com; Ananyev, Konstantin > <konstantin.ananyev@intel.com>; Tiwei Bie <tiwei.bie@intel.com> > Subject: Re: [RFC v3 4/6] eal: add a helper for reading string from sysfs > > On Tue, 1 Jun 2021 11:06:42 +0800 > Chenbo Xia <chenbo.xia@intel.com> wrote: > > > > > +int > > +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) > > +{ > > + FILE *f; > > + > > + f = fopen(filename, "r"); > > + if (f == NULL) { > > + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", > > + __func__, filename); > > Helpful to decode errno. > RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s:%s\n", > __func__, filename, strerror(errno)); Yes. Will fix. Thanks, Chenbo
01/06/2021 05:06, Chenbo Xia: > From: Tiwei Bie <tiwei.bie@intel.com> > > This patch adds a helper for reading string from sysfs. > > Signed-off-by: Cunming Liang <cunming.liang@intel.com> > Signed-off-by: Tiwei Bie <tiwei.bie@intel.com> > --- > lib/eal/common/eal_filesystem.h | 10 ++++++++++ > lib/eal/freebsd/eal.c | 22 ++++++++++++++++++++++ > lib/eal/linux/eal.c | 22 ++++++++++++++++++++++ > lib/eal/version.map | 3 +++ > 4 files changed, 57 insertions(+) 3 separate comments: 1/ How much code is portable between Linux and FreeBSD? I guess the path will be different? 2/ Please think about Windows stub. 3/ Instead of EAL, we should start lib/sysfs/ I have other ideas of sysfs functions for PMD use.
diff --git a/lib/eal/common/eal_filesystem.h b/lib/eal/common/eal_filesystem.h index 5d21f07c20..be4c51ebb2 100644 --- a/lib/eal/common/eal_filesystem.h +++ b/lib/eal/common/eal_filesystem.h @@ -104,4 +104,14 @@ eal_get_hugefile_path(char *buffer, size_t buflen, const char *hugedir, int f_id * Used to read information from files on /sys */ int eal_parse_sysfs_value(const char *filename, unsigned long *val); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Function to read a line from a file on the filesystem. + * Used to read information from files on /sys + */ +__rte_experimental +int rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz); + #endif /* EAL_FILESYSTEM_H */ diff --git a/lib/eal/freebsd/eal.c b/lib/eal/freebsd/eal.c index f4d1676754..002f07f4da 100644 --- a/lib/eal/freebsd/eal.c +++ b/lib/eal/freebsd/eal.c @@ -169,6 +169,28 @@ eal_parse_sysfs_value(const char *filename, unsigned long *val) return 0; } +int +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) +{ + FILE *f; + + f = fopen(filename, "r"); + if (f == NULL) { + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", + __func__, filename); + return -1; + } + + if (fgets(buf, sz, f) == NULL) { + RTE_LOG(ERR, EAL, "%s(): cannot read sysfs file %s\n", + __func__, filename); + fclose(f); + return -1; + } + + fclose(f); + return 0; +} /* create memory configuration in shared/mmap memory. Take out * a write lock on the memsegs, so we can auto-detect primary/secondary. diff --git a/lib/eal/linux/eal.c b/lib/eal/linux/eal.c index ba19fc6347..d5917a48ca 100644 --- a/lib/eal/linux/eal.c +++ b/lib/eal/linux/eal.c @@ -260,6 +260,28 @@ eal_parse_sysfs_value(const char *filename, unsigned long *val) return 0; } +int +rte_eal_parse_sysfs_str(const char *filename, char *buf, unsigned long sz) +{ + FILE *f; + + f = fopen(filename, "r"); + if (f == NULL) { + RTE_LOG(ERR, EAL, "%s(): cannot open sysfs file %s\n", + __func__, filename); + return -1; + } + + if (fgets(buf, sz, f) == NULL) { + RTE_LOG(ERR, EAL, "%s(): cannot read sysfs file %s\n", + __func__, filename); + fclose(f); + return -1; + } + + fclose(f); + return 0; +} /* create memory configuration in shared/mmap memory. Take out * a write lock on the memsegs, so we can auto-detect primary/secondary. diff --git a/lib/eal/version.map b/lib/eal/version.map index fe5c3dac98..3d7fce26a4 100644 --- a/lib/eal/version.map +++ b/lib/eal/version.map @@ -423,6 +423,9 @@ EXPERIMENTAL { rte_version_release; # WINDOWS_NO_EXPORT rte_version_suffix; # WINDOWS_NO_EXPORT rte_version_year; # WINDOWS_NO_EXPORT + + # added in 21.08 + rte_eal_parse_sysfs_str; # WINDOWS_NO_EXPORT }; INTERNAL {