[09/11] libfrog: clean up platform_nproc

Commit Message

Darrick J. Wong Aug. 26, 2019, 9:32 p.m. UTC

From: Darrick J. Wong <[e-mail]>

The platform_nproc function should check for error returns and obviously
garbage values and deal with them appropriately.  Fix the header
declaration since it's part of the libfrog platform support code, not
libxfs.  xfs_scrub will make use of it in the next patch.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 include/libxfs.h           |    1 -
 include/platform_defs.h.in |    2 ++
 libfrog/linux.c            |    9 ++++++++-
 3 files changed, 10 insertions(+), 2 deletions(-)

Patch

diff --git a/include/libxfs.h b/include/libxfs.h
index 3bf7feab..d4a8b209 100644
--- a/include/libxfs.h
+++ b/include/libxfs.h
@@ -135,7 +135,6 @@  extern void	libxfs_device_close (dev_t);
 extern int	libxfs_device_alignment (void);
 extern void	libxfs_report(FILE *);
 extern void	platform_findsizes(char *path, int fd, long long *sz, int *bsz);
-extern int	platform_nproc(void);
 
 /* check or write log footer: specify device, log size in blocks & uuid */
 typedef char	*(libxfs_get_block_t)(char *, int, void *);
diff --git a/include/platform_defs.h.in b/include/platform_defs.h.in
index d111ec6d..adb00181 100644
--- a/include/platform_defs.h.in
+++ b/include/platform_defs.h.in
@@ -77,4 +77,6 @@  typedef unsigned short umode_t;
 # define ASSERT(EX)	((void) 0)
 #endif
 
+extern int	platform_nproc(void);
+
 #endif	/* __XFS_PLATFORM_DEFS_H__ */
diff --git a/libfrog/linux.c b/libfrog/linux.c
index b6c24879..79bd79eb 100644
--- a/libfrog/linux.c
+++ b/libfrog/linux.c
@@ -242,10 +242,17 @@  platform_align_blockdev(void)
 	return max_block_alignment;
 }
 
+/* How many CPUs are online? */
 int
 platform_nproc(void)
 {
-	return sysconf(_SC_NPROCESSORS_ONLN);
+	long nproc = sysconf(_SC_NPROCESSORS_ONLN);
+
+	if (nproc < 1)
+		return 1;
+	if (nproc >= INT_MAX)
+		return INT_MAX;
+	return nproc;
 }
 
 unsigned long